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Zdravkovic, Marija, Marina Deljanin-Ilic, Danijela Trifunovic-Zamaklar, Nikola Milinic, Darko Zdravkovic y Natasa Milic. "Pulsed doppler tissue imaging in the early diagnosis of coronary artery disease". Medical review 60, n.º 9-10 (2007): 444–48. http://dx.doi.org/10.2298/mpns0710444z.
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Introduction Cardiovascular diseases are the leading cause of death in the majority of well-developed countries. Importance of early diagnosis Early diagnosis of coronary artery disease is difficult due to blood vessels remodeling, late manifestations of reduced maximal and normal coronary blood flow, and negative correlation between stenosis and plaque burden. Pulsed Doppler tissue imaging Pulsed Doppler tissue imaging is used for assessment of myocardial velocity, whereas classical Doppler imaging is used for measurement of blood flow velocity. Systolic myocardial velocity profile During the systolic phase only a single myocardial motion is registered - S wave. Diastolic myocardial velocity profile There are early and late myocardial relaxation velocities. Impact of coronary artery disease on myocardial velocities Early to late myocardial relaxation velocity ratio is influenced by coronary artery disease. This paper provides practical guidelines for using pulsed doppler tissue imaging. Conclusion Pulsed Doppler tissue imaging is an excellent procedure for early diagnosis of coronary artery disease. .
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VINEREANU, Dragos, Nicolae FLORESCU, Nicholas SCULTHORPE, Ann C. TWEDDEL, Michael R. STEPHENS y Alan G. FRASER. "Left ventricular long-axis diastolic function is augmented in the hearts of endurance-trained compared with strength-trained athletes". Clinical Science 103, n.º 3 (8 de agosto de 2002): 249–57. http://dx.doi.org/10.1042/cs1030249.
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In order to determine left ventricular global and regional myocardial functional reserve in endurance-trained and strength-trained athletes, and to identify predictors of exercise capacity, we studied 18 endurance-trained and 11 strength-trained athletes with left ventricular hypertrophy (172±27 and 188±39g/m2 respectively), and compared them with 14 sedentary controls. Global systolic (ejection fraction) and diastolic (transmitral flow) function, and regional longitudinal and transverse myocardial velocities [tissue Doppler echocardiography (TDE)], were measured at rest and immediately after exercise. In endurance-trained compared with strength-trained athletes, resting heart rate was lower (59±11 and 76±9beats/min respectively; P<0.001), and the increase at peak exercise was greater (+211% and +139% respectively; P<0.001). In addition, exercise duration, workload, maximal oxygen consumption and global systolic functional reserve (but not peak ejection fraction) were higher in the endurance-trained athletes, and resting global diastolic function (E/A ratio 1.62±0.40 compared with 1.18±0.23; P<0.01) (where E-wave is peak velocity of early-diastolic mitral inflow and A-wave is peak velocity of mitral inflow during atrial contraction) and long-axis diastolic velocities (ETDE/ATDE ratio 2.2±1.2 compared with 1.1±0.3; P<0.01) (where ETDE and ATDE represent peak early- and late-diastolic myocardial or tissue velocity respectively) were augmented. Systolic velocities were similar. Exercise capacity was best predicted from end-diastolic diameter index and E/A ratio at rest, and end-diastolic volume index and diastolic longitudinal velocity during exercise (r = 0.74, n = 43, P<0.001). In conclusion, endurance-trained athletes had higher left ventricular long-axis diastolic velocities, augmented global early diastolic filling, and greater chronotropic and global systolic functional reserve. Maximal oxygen consumption was determined by diastolic loading and early relaxation rather than by systolic function, suggesting that dynamic exercise training improves cardiac performance by an effect on diastolic filling.
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Samuel, T. Jake, Rhys Beaudry, Mark J. Haykowsky, Satyam Sarma y Michael D. Nelson. "Diastolic stress testing: similarities and differences between isometric handgrip and cycle echocardiography". Journal of Applied Physiology 125, n.º 2 (1 de agosto de 2018): 529–35. http://dx.doi.org/10.1152/japplphysiol.00304.2018.
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Cycle echocardiography (CE) is recommended for noninvasive diagnosis of diastolic dysfunction but can be limited by respiratory and movement artifact. Isometric handgrip echocardiography (IHE) is also a robust diastolic discriminator, while avoiding the limitations associated with dynamic exercise. This study sought to compare these two diastolic stress testing approaches. Twelve elderly individuals were recruited from the community (age 71 ± 6 yr). Heart rate, arterial blood pressure, and left ventricular (LV) diastolic function (via echocardiography) were assessed at rest and in response to 3 min of IHE at 40% of their maximal voluntary contraction, followed by 3 min of CE at 20 W. Both IHE and CE caused a significant increase in heart rate and blood pressure, leading to similar increases in myocardial oxygen demand. Both stressors also evoked a similar rise in the ratio between early LV mitral inflow velocity to early lateral annular velocity, a surrogate measure of LV filling pressure. The underlying mechanisms leading to these changes, however, were inherently different. IHE increased mean arterial pressure, and impaired myocardial relaxation, to a greater extent than CE. In contrast, CE augmented cardiac index, and increased early mitral filling velocity, to a great extent than IHE. In conclusion, for the first time, these data highlight several important similarities and differences between IHE and CE. That IHE avoids respiratory and movement artifact, while still serving as a robust diastolic discriminator, supports IHE as a strong alternative to CE for diastolic stress testing. NEW & NOTEWORTHY This is the first study to compare the diastolic stress response between isometric handgrip exercise and conventional cycle exercise. The data suggest that isometric handgrip echocardiography is comparable to conventional cycle echocardiography, both in terms of its hemodynamic challenge and global diastolic stress response. That isometric handgrip echocardiography eliminates both respiratory and movement artifact and is low cost and incredibly portable supports its integration into routine echocardiography exams.
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Lalande, Sophie, Robert J. Petrella y J. Kevin Shoemaker. "Effect of exercise training on diastolic function in metabolic syndrome". Applied Physiology, Nutrition, and Metabolism 38, n.º 5 (mayo de 2013): 545–50. http://dx.doi.org/10.1139/apnm-2012-0383.
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It has been reported that metabolic syndrome (MetS) impairs left ventricular (LV) diastolic function. The objective of this study was to determine whether exercise training can improve LV diastolic function in individuals with MetS. Twenty-eight individuals with MetS (9 males, aged 60 ± 5 years) underwent a 1-year combined endurance and resistance exercise training program; maximal aerobic capacity (V̇O2max), blood pressure, blood markers, and LV diastolic function were measured at weeks 0, 12, 24, and 52 throughout the training. Pulsed wave Doppler echocardiography across the mitral valve was used to assess peak early flow velocity (E) and peak atrial flow velocity (A) to determine the E/A ratio. Individuals with MetS had a reversed E/A ratio, suggesting impaired LV relaxation, the first stage of LV diastolic dysfunction. Exercise training reduced systolic blood pressure (SBP) (129 ± 14 to 120 ± 12 mm Hg; p < 0.01) and increased V̇O2max (29.2 ± 6.3 to 33.4 ± 6.5 mL·kg−1·min−1; p < 0.01) and high-density lipoprotein cholesterol (1.04 ± 0.21 to 1.12 ± 0.25 mmol·L−1; p = 0.02), but did not improve LV diastolic function. Individuals with an E/A ratio <1 at the start of training had a tendency toward an increased E/A ratio (p = 0.12) accompanied by significant decreases in SBP and increases in V̇O2max with exercise training. Combined resistance and aerobic exercise training improved cardiometabolic health but did not improve the impaired LV diastolic function of individuals with MetS.
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Petrella, Robert J., Donald A. Cunningham y David H. Paterson. "Effects of 5-Day Exercise Training in Elderly Subjects on Resting Left Ventricular Diastolic Function and VO2max". Canadian Journal of Applied Physiology 22, n.º 1 (1 de febrero de 1997): 37–47. http://dx.doi.org/10.1139/h97-004.
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We evaluated the effects of short-term, high-intensity exercise training and detraining on resting left ventricular diastolic function (LVDF) and maximal aerobic power (VO2max) in 7 sedentary older (age = 68 ± 4 years) men (n = 5) and women (n = 2). Training consisted of cycling for 60 min with power output set at 70% (Day 1), 80% (Day 2), and 90% (Days 3-5) of the pretraining peak work rate. Detraining consisted of a return to regular exercise habits. LVDF increased 10% in the early (E) flow velocity, decreased 18% in the late (A) flow velocity wave, and decreased 31% in the isovolumic relaxation time. VO2max was increased 12% while plasma volume (PV) increased 10% following, training and returned to baseline after detraining. The exercise-induced change in VO2max was directly related to the change in E/A (r =.52) and indirectly related to the change in IVRT (r = −.62). It was concluded that short-term, high-intensity exercise training improves LVDF and is tolerated well in older subjects, and that the calculated changes in PV and aerobic power are similar to those observed previously in a younger population. Key words: aging, training, cardiac filling
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Varagic, Jasmina, Edward D. Frohlich, Dinko Susic, Jwari Ahn, Luis Matavelli, Begoña López y Javier Díez. "AT1receptor antagonism attenuates target organ effects of salt excess in SHRs without affecting pressure". American Journal of Physiology-Heart and Circulatory Physiology 294, n.º 2 (febrero de 2008): H853—H858. http://dx.doi.org/10.1152/ajpheart.00737.2007.
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Our recent studies have demonstrated that salt excess in the spontaneously hypertensive rat (SHR) produces a modestly increased arterial pressure while promoting marked myocardial fibrosis and structural damage associated with altered coronary hemodynamics and ventricular function. The present study was designed to determine the efficacy of an angiotensin II type 1 (AT1) receptor blocker (ARB) in the prevention of pressure increase and development of target organ damage from high dietary salt intake. Eight-week-old SHRs were given an 8% salt diet for 8 wk; their age- and gender-matched controls received standard chow. Some of the salt-loaded rats were treated concomitantly with ARB (candesartan; 10 mg·kg−1·day−1). The ARB failed to reduce the salt-induced rise in pressure, whereas it significantly attenuated left ventricular (LV) remodeling (mass and wall thicknesses), myocardial fibrosis (hydroxyproline concentration and collagen volume fraction), and the development of LV diastolic dysfunction, as shown by longer isovolumic relaxation time, decreased ratio of peak velocity of early to late diastolic waves, and slower LV relaxation (minimum first derivative of pressure over time/maximal LV pressure). Without affecting the increased pulse pressure by high salt intake, the ARB prevented the salt-induced deterioration of coronary and renal hemodynamics but not the arterial stiffening or hypertrophy (pulse wave velocity and aortic mass index). Additionally, candesartan prevented the salt-induced increase in kidney mass index and proteinuria. In conclusion, the ARB given concomitantly with dietary salt excess ameliorated salt-related structural and functional cardiac and renal abnormalities in SHRs without reducing arterial pressure. These data clearly demonstrated that angiotensin II (via AT1receptors), at least in part, participated importantly in the pressure-independent effects of salt excess on target organ damage of hypertension.
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O’Driscoll, Jamie M., Steven M. Wright, Katrina A. Taylor, Damian A. Coleman, Rajan Sharma y Jonathan D. Wiles. "Cardiac autonomic and left ventricular mechanics following high intensity interval training: a randomized crossover controlled study". Journal of Applied Physiology 125, n.º 4 (1 de octubre de 2018): 1030–40. http://dx.doi.org/10.1152/japplphysiol.00056.2018.
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Physical inactivity and sedentary behavior is associated with increased cardiovascular disease risk. Short duration high-intensity interval training (HIIT) has been shown to improve important health parameters. The aim of the present study was to assess the combined adaptations of the cardiac autonomic nervous system and myocardial functional and mechanical parameters to HIIT. Forty physically inactive and highly sedentary men completed two weeks of HIIT and control period. The HIIT protocol consisted of 3 × 30-s maximal cycle ergometer sprints against a resistance of 7.5% body weight, interspersed with 2 min of active recovery. Total power spectral density (PSD) and associated low-frequency (LF) and high-frequency (HF) power spectral components of heart rate variability were recorded. Conventional and speckle tracking echocardiography recorded left ventricular (LV) structural, functional, and mechanical parameters. HIIT produced a significant increase in total log-transformed (ln) PSD and ln HF and a significant decrease in LF/HF ratio (all P < 0.05) compared with the control period. HIIT produced significant improvements in LV diastolic function, including lateral E′, estimated filling pressure (E/E′ ratio), E deceleration time, and isovolumetric relaxation time ( P < 0.05 for all). Fractional shortening was the only conventional marker of LV systolic function to significantly improve ( P < 0.05). In this setting, there were significant improvements in global peak systolic strain rate, early and late diastolic strain rate, and early to late diastolic strain rate ratio, as well as apical rotation, apical systolic and diastolic rotation velocity, apical radial and circumferential strain and strain rate, LV torsion, and LV systolic and diastolic torsion velocity (all P < 0.05). A short-term program of HIIT was associated with a significant increase in cardiac autonomic modulation, demonstrated by a residual increase in cardiac vagal activity as well as significantly improved cardiac function and mechanics. This study demonstrates that HIIT may be an important stimulus to reduce the health implications associated with physical inactivity and sedentary behavior. NEW & NOTEWORTHY This is the first study to measure the combined adaptations of the cardiac autonomic nervous system and myocardial function and mechanics following high-intensity interval training (HIIT). This study demonstrates that a 2-wk HIIT intervention provides significant improvements in cardiac autonomic modulation and myocardial function and mechanics in a large cohort of young physically inactive and highly sedentary individuals. HIIT may be a powerful stimulus to reduce the health implications associated with physical inactivity and sedentary behavior.
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PASHCHENKO, E. V., A. I. CHESNIKOVA, V. P. TERENTYEV, V. I. KUDINOV y E. A. DEVETYAROVA. "STRUCTURAL AND FUNCTIONAL FEATURES OF LEFT VENTRICLE IN PATIENTS WITH HEART FAILURE, CORONARY HEART DISEASE AND THYROTOXICOSIS". Kuban Scientific Medical Bulletin 25, n.º 4 (3 de octubre de 2018): 68–74. http://dx.doi.org/10.25207/1608-6228-2018-25-4-68-74.
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Aim. This study was designed to determine the structural and functional features of left ventricle in patients with heart failure, coronary heart disease and thyrotoxicosis.Materials and methods. 85 patients aged 58.3±5.6 years were divided into 3 groups: the main one – 25 patients with coronary heart disease (CHD), chronic heart failure (CHF) II-III functional classes (FC) and thyrotoxicosis, average age –59.23±3.81; the 1st comparison group – 30 patients with CHD and CHF FC II-III without thyroid dysfunction, the average age – 57.6±2.73; the 2nd comparison group – 30 patients with thyrotoxicosis without concomitant cardiovascular diseases (CVD), the average age – 45.4±3.51. The structure and function of the thyroid gland were examined in all patients. The echocardiographic (EchoCG) examination was performed to evaluate the structural and functional indicators of the left ventricle (LV).Results. The LV pathologic remodeling in patients of the main group is represented by two types: concentric left ventricle hypertrophy (CLVH) and eccentric left ventricle hypertrophy (ELVH), CLVH was more common than in patients without thyroid dysfunction but with CHF and CHD (84.0%, р=0.01). The LV myocardium contractility was reduced in patients of both groups with CHF, the values of the ejection fraction corresponded with the intermediate type of HF, there was no significant difference between the indices (p = 0.1). The main group had significantly more pronounced decrease in the ratio of the blood flow velocity of early diastolic filling of the LV and the maximal atrial systolic velocity (E / A) − 0.63 and the increase in the isovolumic relaxation time (IVRT) – 84.69 ms in comparison with the indicators of the CHD and CHF patients without thyroid dysfunction (p = 0.021, p = 0.034).Conclusion. For patients with CHF, CHD and thyrotoxicosis, predominance of LV remodeling according to the type of CLVH (84.0% of cases) is typical as well as a moderate decrease in the contractility of the LV and a more pronounced diastolic dysfunction. It determines the structural and functional features of the left ventricle in patients with CHF with this comorbidity.
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Kawano, Yoko, K. Ohmori, Yoshihiro Wada, Isao Kondo, Katsufumi Mizushige, Shoichi Senda, Shiro Nozaki y Masakazu Kohno. "A novel color M-mode Doppler echocardiographic index for left ventricular relaxation: depth of the maximal velocity point of left ventricular inflow in early diastole". Heart and Vessels 15, n.º 5 (septiembre de 2000): 205–13. http://dx.doi.org/10.1007/s003800070009.
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Carrick-Ranson, Graeme, Jeffrey L. Hastings, Paul S. Bhella, Shigeki Shibata, Naoki Fujimoto, M. Dean Palmer, Kara Boyd y Benjamin D. Levine. "Effect of healthy aging on left ventricular relaxation and diastolic suction". American Journal of Physiology-Heart and Circulatory Physiology 303, n.º 3 (1 de agosto de 2012): H315—H322. http://dx.doi.org/10.1152/ajpheart.00142.2012.
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Doppler ultrasound measures of left ventricular (LV) active relaxation and diastolic suction are slowed with healthy aging. It is unclear to what extent these changes are related to alterations in intrinsic LV properties and/or cardiovascular loading conditions. Seventy carefully screened individuals (38 female, 32 male) aged 21–77 were recruited into four age groups (young: <35; early middle age: 35–49; late middle age: 50–64 and seniors: ≥65 yr). Pulmonary capillary wedge pressure (PCWP), stroke volume, LV end-diastolic volume, and Doppler measures of LV diastolic filling were collected at multiple loading conditions, including supine baseline, lower body negative pressure to reduce LV filling, and saline infusion to increase LV filling. LV mass, supine PCWP, and heart rate were not affected significantly by aging. Measures of LV relaxation, including isovolumic relaxation time and the time constant of isovolumic pressure decay increased progressively, whereas peak early mitral annular longitudinal velocity decreased with advancing age ( P < 0.001). The propagation velocity of early mitral inflow, a noninvasive measure of LV suction, decreased with aging with the greatest reduction in seniors ( P < 0.001). Age-related differences in LV relaxation and diastolic suction were not attenuated significantly when PCWP was increased in older subjects or reduced in the younger subjects. There is an early slowing of LV relaxation and diastolic suction beginning in early middle age, with the greatest reduction observed in seniors. Because age-related differences in LV dynamic diastolic filling parameters were not diminished significantly with significant changes in LV loading conditions, a decline in ventricular relaxation is likely responsible for the alterations in LV diastolic filling with senescence.
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Ruan, Qinyun, Liyun Rao, Katherine J. Middleton, Dirar S. Khoury y Sherif F. Nagueh. "Assessment of left ventricular diastolic function by early diastolic mitral annulus peak acceleration rate: experimental studies and clinical application". Journal of Applied Physiology 100, n.º 2 (febrero de 2006): 679–84. http://dx.doi.org/10.1152/japplphysiol.00671.2005.
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We sought to examine the hemodynamic determinants and clinical application of the peak acceleration rate of early (Ea) diastolic velocity of the mitral annulus by tissue Doppler. Simultaneous left atrial and left ventricular (LV) catheterization and Doppler echocardiography were performed in 10 dogs. Preload was altered using volume infusion and caval occlusion, whereas myocardial lusitropic state was altered with dobutamine and esmolol. The clinical application was examined in 190 consecutive patients (55 control, 41 impaired relaxation, 46 pseudonormal, and 48 restrictive LV filling). In addition, in 60 consecutive patients, we examined the relation between it and mean wedge pressure with simultaneous Doppler echocardiography and right heart catheterization. In canine studies, a significant positive relation was present between peak acceleration rate of Ea and transmitral pressure gradient only in the stages with normal or enhanced LV relaxation, but with no relation in the stages where the time constant of LV relaxation (τ) was ≥50 ms. Its hemodynamic determinants were τ, LV minimal pressure, and transmitral pressure gradient. In clinical studies, peak acceleration rate of Ea was significantly lower in patients with impaired LV relaxation irrespective of filling pressures ( P < 0.001) and with similar accuracy to peak Ea velocity (area under the curve for septal and lateral peak acceleration rates: both 0.78) in identifying these patients. No significant relation was observed between peak acceleration rate and mean wedge pressure. Peak acceleration rate of Ea appears to be a useful index of LV relaxation but not of filling pressures and can be applied to identify patients with impaired LV relaxation irrespective of their filling pressures.
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Akyol, A., S. Akdag, M. Asker, HA Gumrukcuoglu, R. Duz, KC Demirel, F. Ozturk et al. "Effects of lowered dialysate sodium on left ventricle function and brain natriuretic peptide in maintenance of hemodialysis patients". Human & Experimental Toxicology 36, n.º 2 (11 de julio de 2016): 128–34. http://dx.doi.org/10.1177/0960327116639362.
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Introduction: Impaired diastolic flow is characterized by decreased left ventricular (LV) filling diastole, abnormal LV distensibility, or delayed relaxation. B-Type natriuretic peptide (BNP) is an indicator of various cardiovascular diseases and body volume status. The aim of this study was to determine whether the lowering of dialysate sodium (Na) levels is effective on LV systolic and diastolic parameters and BNP in the maintenance of hemodialysis patients. Materials and Methods: The study included 49 chronic hemodialysis patients. Left atrium (LA) diameter and LV ejection fraction, LV systolic and diastolic diameter, deceleration time (DT), pulmonary artery pressure (PAP), inferior vena cava diameter (IVCD), early diastolic transmitral flow ( E) and late diastolic transmitral flow ( A) velocities, E/ A ratio, isovolumic relaxation time, peak early diastolic velocity ( E′), late diastolic velocity ( A′) of tissue Doppler mitral annulus, and flow propagation velocity of mitral inflow ( Vp) were measured before and 6 months after hemodialysis with low Na dialysate. Results: Six months after low Na hemodialysis, a decrease was observed in echocardiographic parameters such as PAP and IVCD ( p < 0.05, p < 0.001, and p < 0.001, respectively). However, a significant difference was not observed in LA diameter. In LV diastolic measurement of E and A waves, E/ A ratio, DT, Vp, septal E′ and A′, and lateral E′ and A′ exhibited significant improvement by low Na HD. BNP level was significantly reduced ( p < 0.001). Conclusions: Lowered dialysate Na concentration improves PAP, IVCD, and LV diastolic properties assessed by mitral inflow filling, tissue Doppler velocity, and mitral inflow velocity propagation.
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Slama, Michel, Jwari Ahn, Marcel Peltier, Julien Maizel, Denis Chemla, Jasmina Varagic, Dinko Susic, Christophe Tribouilloy y Edward D. Frohlich. "Validation of echocardiographic and Doppler indexes of left ventricular relaxation in adult hypertensive and normotensive rats". American Journal of Physiology-Heart and Circulatory Physiology 289, n.º 3 (septiembre de 2005): H1131—H1136. http://dx.doi.org/10.1152/ajpheart.00345.2004.
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This study was performed to validate echocardiographic and Doppler techniques for the assessment of left ventricular (LV) diastolic function in spontaneously hypertensive rats (SHR) and normotensive Wistar rats. In 11 Wistar rats and 20 SHR, we compared 51 sets of invasive and Doppler LV diastolic indexes. Noninvasive indexes of LV relaxation were related to the minimal rate of pressure decline (−dP/d tmin), particularly isovolumic relaxation time (IVRT), the Tei index, the early velocity of the mitral annulus ( Em) using Doppler tissue imaging, and early mitral flow propagation velocity using M-mode color ( r = 0.28–0.56 and P < 0.05–0.0001). When the role of systolic load was considered, the correlation between Doppler indexes of LV diastolic function and relaxation rate [(−dP/d tmin)/LV systolic pressure] improved ( r = 0.48–0.86 and P = 0.004–0.0001, respectively). Similarly, Doppler indexes of LV diastolic function and the time constant of isovolumic LV relaxation (τ) correlated well ( r = 0.50–0.84 and P = 0.0002–0.0001, respectively). In addition, eight SHR and eight Wistar rats were compared; their LV end-diastolic diameters were similar, whereas the SHR LV mass was greater. Furthermore, IVRT and Tei index were significantly higher and Em was lower in SHR. Moreover, τ was higher in SHR, demonstrating impaired LV relaxation. In conclusion, LV relaxation can be assessed reliably using echocardiographic and Doppler techniques, and, using these indexes, impaired relaxation was demonstrated in SHR.
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POERNER, Tudor C., Björn GOEBEL, Petra UNGLAUB, Tim SÜSELBECK, Jens J. KADEN, Martin BORGGREFE y Karl K. HAASE. "Non-invasive evaluation of left ventricular filling pressures in patients with abnormal relaxation". Clinical Science 106, n.º 5 (1 de mayo de 2004): 485–94. http://dx.doi.org/10.1042/cs20030169.
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The aim of the present study was to assess the ability of several echocardiographic and TDI (tissue Doppler imaging) parameters to predict an elevated LVEDP (left ventricular end-diastolic pressure) in patients with abnormal relaxation. Eighty-two consecutive patients presenting with an E/A ratio (ratio of early-to-late diastolic peak transmitral velocity) <0.9 scheduled for left heart catheterization underwent echocardiography, including TDI, and measurement of LVEDP using fluid-filled catheters. The difference in duration between PVR (retrograde peak in the pulmonary veins) and A (ΔPVR-A) was calculated from pulsed Doppler recordings. VP (propagation velocity of the early mitral inflow) was determined by colour M-mode. TDI measurements included E´ (early diastolic peak myocardial velocities near the lateral mitral annulus), MVG (the early diastolic transmyocardial velocity gradient of the posterior basal wall) and the PRT (peak relaxation time), determined as the time interval between aortic valve closure and peak E´. Fifty-six patients presented with LVEDP values <15 mmHg, whereas an LVEDP >15 mmHg was found in 26 patients. The index ΔPVR-A showed a significant linear correlation with LVEDP (r=0.7, P<0.001) and provided the highest predictive accuracy for the identification of LVEDP >15 mmHg [AUC (area under receiver operating characteristic curve)=0.83], followed by PRT (AUC=0.67), whereas other TDI-derived parameters failed to reach significance. In conclusion, ΔPVR-A enabled the most accurate non-invasive estimation of LVEDP. A prolonged peak relaxation time was the only TDI-derived index that differed significantly between patient groups.
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Bartosh, F. L., L. F. Bartosh y T. S. Adonina. "Left ventricular diastolic function in hypertensive patients with atrial fibrillation". "Arterial’naya Gipertenziya" ("Arterial Hypertension") 18, n.º 2 (28 de abril de 2012): 142–47. http://dx.doi.org/10.18705/1607-419x-2012-18-2-142-147.
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Objective. To study the features of the impact of atrial fibrillation on left ventricular diastolic function in hypertensive patients. Design and methods. We examined three groups of patients: hypertensive patients with atrial fibrillation, hypertensive patients with sinus rhythm and patients with idiopathic form of atrial fibrillation. All patients underwent cardiac ultrasound examination (Vivid 7 Dimension, General Electric). Results. The integral of blood flow linear velocity (VTI), period of pressure gradient half decrease (PHT) between left chambers of heart and time of transmitral blood flow (TE) were greater in patients of second and third groups compared to first group. They did not differ in second and third groups. The time of isovolumic relaxation (IVRT) was 0,102 ± 0,015; 0,091 ± 0,012 and 0,073 ± 0,013 seconds in first, second and third groups, respectively. The differences between all groups are significant (p = 0,001). The mean values of maximal (Vmax) and middle velocity (VMN), maximal (Gmax) and middle (GMN) pressure gradient between left heart chambers did not differ between groups. Conclusion. Atrial fibrillation contributes the development of left ventricular diastolic dysfunction: it reduces VTI, decelerates IVRT and shortens PHT significantly.
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Riordan, Matt M. y Sándor J. Kovács. "Absence of diastolic mitral annular oscillations is a marker for relaxation-related diastolic dysfunction". American Journal of Physiology-Heart and Circulatory Physiology 292, n.º 6 (junio de 2007): H2952—H2958. http://dx.doi.org/10.1152/ajpheart.01356.2006.
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Although Doppler tissue imaging frequently indicates the presence of mitral annular oscillations (MAO) following the E′ wave (E″ wave, etc.), only recently was it shown that annular “ringing” follows the rules of damped harmonic oscillatory motion. Oscillatory model-based analysis of E′ and E″ waves provides longitudinal left ventricular (LV) stiffness ( k′), relaxation/viscoelasticity ( c′), and stored elastic strain ( xo′) parameters. We tested the hypothesis that presence (MAO+) vs. absence (MAO−) of diastolic MAO is an index of superior LV relaxation by analyzing simultaneous echocardiographic-hemodynamic data from 35 MAO+ and 20 MAO− normal ejection fraction (EF) subjects undergoing cardiac catheterization. Echocardiographic annular motion and transmitral flow data were analyzed with a previously validated kinematic model of filling. Invasive and noninvasive diastolic function (DF) indexes differentiated between MAO+ and MAO− groups. Specifically, the MAO+ group had a shorter time constant of isovolumic relaxation [τ; 51 (SD 13) vs. 67 (SD 27) ms; P < 0.01] and isovolumic relaxation time [63 (SD 16) vs. 82 (SD 17) ms; P < 0.001] and greater ratio of peak E-wave to peak A-wave velocity [1.19 (SD 0.31) vs. 0.97 (SD 0.31); P < 0.05]. The MAO+ group had greater peak lateral mitral annulus velocity [E′; 17.5 (SD 3.1) vs. 13.5 (SD 3.8) cm/s; P < 0.001] and LVEF [71.2 (SD 7.5)% vs. 65.4 (SD 9.1)%; P < 0.05] and lower heart rate [65 (SD 9) vs. 74 (SD 9) beats/min, P < 0.001]. Additional conventional and kinematic modeling-derived indexes were highly concordant with these findings. We conclude that absence of early diastolic MAO is an easily discernible marker for relaxation-related diastolic dysfunction. Quantitation of MAO via stiffness and relaxation/viscoelasticity parameters facilitates quantitative assessment of regional (i.e., longitudinal) DF and may improve diagnosis of diastolic dysfunction.
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Hanssen, Henner, Alexandra Keithahn, Gernot Hertel, Verena Drexel, Heiko Stern, Tibor Schuster, Dan Lorang et al. "Magnetic resonance imaging of myocardial injury and ventricular torsion after marathon running". Clinical Science 120, n.º 4 (2 de noviembre de 2010): 143–52. http://dx.doi.org/10.1042/cs20100206.
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Recent reports provide indirect evidence of myocardial injury and ventricular dysfunction after prolonged exercise. However, existing data is conflicting and lacks direct verification of functional myocardial alterations by CMR [cardiac MR (magnetic resonance)]. The present study sought to examine structural myocardial damage and modification of LV (left ventricular) wall motion by CMR imaging directly after a marathon. Analysis of cTnT (cardiac troponin T) and NT-proBNP (N-terminal pro-brain natriuretic peptide) serum levels, echocardiography [pulsed-wave and TD (tissue Doppler)] and CMR were performed before and after amateur marathon races in 28 healthy males aged 41±5 years. CMR included LGE (late gadolinium enhancement) and myocardial tagging to assess myocardial injury and ventricular motion patterns. Echocardiography indicated alterations of diastolic filling [decrease in E/A (early transmitral diastolic filling velocity/late transmitral diastolic filling velocity) ratio and E′ (tissue Doppler early transmitral diastolic filling velocity)] postmarathon. All participants had a significant increase in NT-proBNP and/or cTnT levels. However, we found no evidence of LV LGE. MR tagging demonstrated unaltered radial shortening, circumferential and longitudinal strain. Myocardial rotation analysis, however, revealed an increase of maximal torsion by 18.3% (13.1±3.8 to 15.5±3.6 °; P=0.002) and maximal torsion velocity by 35% (6.8±1.6 to 9.2±2.5 °·s−1; P<0.001). Apical rotation velocity during diastolic filling was increased by 1.23±0.33 °·s−1 after marathon (P<0.001) in a multivariate analysis adjusted for heart rate, whereas peak untwist rate showed no relevant changes. Although marathon running leads to a transient increase of cardiac biomarkers, no detectable myocardial necrosis was observed as evidenced by LGE MRI (MR imaging). Endurance exercise induces an augmented systolic wringing motion of the myocardium and increased diastolic filling velocities. The stress of marathon running seems to be better described as a burden of myocardial overstimulation rather than cardiac injury.
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Popovic, Zoran, Milind Y. Desai, Adisai Buakhamsri, Chirapa Puntawagkoon, Allen Borowski, Benjamin D. Levine, Wai Hong Wilson Tang y James D. Thomas. "IS MITRAL ANNULUS EARLY DIASTOLIC VELOCITY A CLINICALLY RELEVANT INDEX OF LEFT VENTRICULAR RELAXATION?" Journal of the American College of Cardiology 55, n.º 10 (marzo de 2010): A79.E738. http://dx.doi.org/10.1016/s0735-1097(10)60739-5.
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Baldi, James C., Kendra McFarlane, Helen C. Oxenham, Gillian A. Whalley, Helen J. Walsh y Robert N. Doughty. "Left ventricular diastolic filling and systolic function of young and older trained and untrained men". Journal of Applied Physiology 95, n.º 6 (diciembre de 2003): 2570–75. http://dx.doi.org/10.1152/japplphysiol.00441.2003.
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Aging is associated with impaired early diastolic filling; however, the effect of endurance training on resting diastolic function in older subjects is unclear. Heart rate and ventricular loading conditions affect mitral inflow velocities measured by Doppler echocardiography; therefore, tissue Doppler imaging of mitral annular velocity, which is relatively preload independent, was combined with mitral inflow velocity and maximal oxygen consumption (V̇o2 max) in young (20-35 yr) and older (60-80 yr) trained and untrained men to determine whether endurance training is associated with an attenuation of age-associated changes in diastolic filling. As expected, V̇o2 max was higher in trained men ( P < 0.01) and lower in older men ( P < 0.01). Peak early mitral inflow velocity (E) and early-to-late mitral inflow velocity ratios were lower in older vs. young men ( P < 0.01); however, there was no training effect ( P > 0.05). Peak early mitral annular velocity (E′) was higher and peak late mitral annular velocity (A′) was lower in young vs. older men ( P < 0.01). A significant interaction effect was found for A′, E′/A′, and peak systolic mitral annular velocity (S′). Training was associated with lower A′ in young and higher A′ in older men. S′ was greater in trained vs. untrained older men ( P < 0.05), but it was similar in trained and untrained young men. These findings suggest that early diastolic filling is not affected by training in older men, and the effect of training on A′ and S′ is different in young and older men.
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Bright, JM, ME Herrtage y JF Schneider. "Pulsed Doppler assessment of left ventricular diastolic function in normal and cardiomyopathic cats". Journal of the American Animal Hospital Association 35, n.º 4 (1 de julio de 1999): 285–91. http://dx.doi.org/10.5326/15473317-35-4-285.
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Left ventricular (LV) diastolic function was evaluated in 16 cats with primary hypertrophic cardiomyopathy (HCM) using pulsed Doppler (PD) assessment of transmitral flow and isovolumic relaxation time. Data obtained was compared to data from 12 healthy, adult, research cats. Compared to normal cats, the HCM group showed significantly (p value less than 0.05) reduced early LV inflow velocities (mean +/- standard error [SE], peak velocity of 0.70+/-0.04 m/s versus 0.54+/-0.04 m/s and integrated velocity of 0.48+/-0.08 m/s versus 0.37+/-0.03 m/s); a reduced rate of deceleration of early inflow (mean+/-SE, -12.0+/-1.0 m/s2 versus -5.1+/-1.1 m/s2); prolonged isovolumic relaxation time (mean +/- SE, 45.7+/-3.3 ms versus 76.0+/-3.1 ms); and increased atrial systolic flow velocities (mean +/- SE, peak velocity of 0.29+/-0.04 m/s versus 0.48+/-0.04 m/s and integrated velocity of 0.21+/-0.03 m/s versus 0.34+/-0.03 m/s). The results suggest that PD provides a noninvasive method of identifying and quantifying functional diastolic impairment in cats with HCM.
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Avdić, Sevleta, Zulfo Mujčinović, Mensura Ašćerić, Sabrija Nukić, Zumreta Kušljugić, Elnur Smajić y Sedija Arapčić. "Left Venticular Diastolic Dysfunction in Essential Hypertension". Bosnian Journal of Basic Medical Sciences 7, n.º 1 (20 de febrero de 2007): 15–20. http://dx.doi.org/10.17305/bjbms.2007.3082.
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Diastolic dysfunction is very frequent and is actually sign of manifest heart weakness. Over 40% of patients with heart weakness have isolated left ventricular diastolic dysfunction (LVDD). New diagnostics methods as Doppler Echocardiography with close monitoring enables precise and early LVDD diagnose. In all diastolic phases artery hypertension weakens relaxation and left ventricular hypertrophy (LVH) weakens compliance also. The purpose of this study is to demonstrate importance of all LVDD. Doppler echocardiography parameters usage and its important echocardiography characteristic in case of hypertensive patients. This study represents 64 patients with essential hypertension - random sample. Three patients had atrial fibrillation. Besides anamnestic data collection, echocardiography evaluation was undertaken on all patients. For LVDD diagnose following parameters were used: isovolumic relaxation time (IVRT), peak early filling velocity (E), peak atrial filling velocity (A), E/A ratio, DT (deceleration time), left ventricular (LV) mass. Left ventricular hypertrophy (LVH) was verified for 57 patients. Seven hypertensive patients didn't have verified LVH. Comparing patients with LVH with those without LVH differences were observed: patients with LVH had a longer IVRT, lower E/A ratio, A wave growth, IVRT directly correlates with LV mass increase and backward correlation LV mass with E/A was noticed. Among patients with LVH with E/A ratio =or> 1-1,5 and based on transmitral flow we used IVRT duration and pulse Doppler with volume sample over lateral mitral annulus measuring mitral annulus velocity. It appeared that it corresponds with IVRT duration in LVDD evaluation. Patients with atrial fibrillation had considerably extended IVRT that indicates LVDD existence. Patients with left ventricular hypertrophy were older and they have higher left ventricular mass comparing with patients without left ventricular hypertrophy. In case of patients with essential hypertension all above mentioned LVDD parameters have to be defined, specially IVRT duration for determination of LVDD existence in case of all patients with essential hypertension with and without LVH and in case of associated atrial fibrillation presence. It is necessary to tend to, as early as possible, detect LVDD and it's prevention with improved essential hypertension monitoring.
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Evin, Morgane, Alban Redheuil, Gilles Soulat, Ludivine Perdrix, Golmehr Ashrafpoor, Alain Giron, Jérôme Lamy et al. "Left atrial aging: a cardiac magnetic resonance feature-tracking study". American Journal of Physiology-Heart and Circulatory Physiology 310, n.º 5 (1 de marzo de 2016): H542—H549. http://dx.doi.org/10.1152/ajpheart.00504.2015.
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Importance of left atrial (LA) phasic function evaluation is increasingly recognized for its incremental value in terms of prognosis and risk stratification. LA phasic deformation in the pathway of normal aging has been characterized using echocardiographic speckle tracking. However, no data are available regarding age-related variations using feature-racking (FT) techniques from standard cine magnetic resonance imaging (MRI). We studied 94 healthy adults (41 ± 14 yr, 47 women), who underwent MRI and Doppler echocardiography on the same day for left ventricular (LV) diastolic function evaluation. From cine MRI, longitudinal strain and strain rate, radial motion fraction, and radial relative velocity, respectively, corresponding to the reservoir, conduit, and LA contraction phases, were measured using dedicated FT software. Longitudinal strain and radial motion fraction decreased gradually and significantly with aging for both reservoir ( r > 0.31, P < 0.003) and conduit ( r > 0.54, P < 0.001) phases, whereas they remained unchanged during the LA contraction phase. Subsequently, the LA contraction-to-reservoir ratio increased significantly with age ( r > 0.44, P < 0.001). Longitudinal strain rate and radial relative velocity significantly decreased with age (reservoir: r = 0.39, P < 0.001, conduit: r > 0.54, P < 0.001), and these associations tended to be stronger in women than in men. Finally, associations of LA functional indexes with age were stronger in individuals with lower transmitral early-to-atrial maximal velocity ratio and mitral annulus maximal longitudinal velocity, as well as higher transmitral early maximal-to-mitral annulus maximal longitudinal velocity ratio, highlighting the LV-LA interplay. Age-related changes in LA phasic function indexes were quantified by cine MRI images using a FT technique and were significantly related to age and LV diastolic function.
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Milutinovic, Suzana y Radovan Karadzic. "The influence of glycemia on the left ventricular diastolic function in patients with arterial hypertension". Medical review 61, n.º 1-2 (2008): 71–74. http://dx.doi.org/10.2298/mpns0802071m.
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Introduction. Arterial hypertension is a disease which has influence on the left ventricular diastolic function. It has been suggested that impairment of the left ventricular diastolic function in patients with diabetes mellitus is due to arterial hypertension and diffuse peripherial and coronary atherosclerosis which appear early in diabetic patients. Now, however, it is thought, that other mechanisms are responsable for the development of diabetic cardiomyopathy. The aim of the study was to investigate the effect of glycemia on the left ventricular diastolic function in patients with arterial hypertension. Methods. The study included 60 patients with arterial hypertension: 30 (50,00%) patients with diabetes mellitus and 30 (50,00%) with?out diabetes mellitus. The parameters of diastolic function were measured by the pulsed Doppler echocardiographic technique. Isovolumetric relaxation time, deceleration time, maximum velocity of the early stage of ventricular filling, maximum velocity of the late stage of ventricular filling and the early/late stage of ventricular filling ratio were used to assess the diastolic function. Results. The patients with arterial hypertension and diabetes mellitus compared to the patients with arterial hypertension without diabetes mellitus were significantly obese (p 0.001), had significantly higher glycemia (p<0.0001) and left atrial volume (p<0.05). The patients with arterial hypertension and diabetes mellilus compared to the patients with arterial hypertension without diabetes mellitus had significanllly: longer deceleration time (p< 0.05), lower velocity of early stage of ventricular filling (p<0.05) and lower early/late stage oj ventricular filling ratio (p<0.01). Conclusion. Diastolic function parameters of patients with diabetes mellitus are significantly changed: deceleration time is longer, early stage of ventricular filling and early/late ventricular filling ratio are lower.
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Bhagavan, Druv, William M. Padovano y Sándor J. Kovács. "Alternative diastolic function models of ventricular longitudinal filling velocity are mathematically identical". American Journal of Physiology-Heart and Circulatory Physiology 318, n.º 5 (1 de mayo de 2020): H1059—H1067. http://dx.doi.org/10.1152/ajpheart.00681.2019.
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The spatiotemporal features of normal in vivo cardiac motion are well established. Longitudinal velocity has become a focus of diastolic function (DF) characterization, particularly the tissue Doppler e′-wave, manifesting in early diastole when the left ventricle (LV) is a mechanical suction pump (dP/dV < 0). To characterize DF and elucidate mechanistic features, several models have been proposed and have been previously compared algebraically, numerically, and in their ability to fit physiological velocity data. We analyze two previously noncompared models of early rapid-filling lengthening velocity (Doppler e′-wave): parametrized diastolic filling (PDF) and force balance model (FBM). Our initial numerical experiments sampled FBM-generated e′( t) contours as input to determine PDF model predicted fit. The resulting exact numerical agreement [standard error of regression (SER) = 9.06 × 10−16] was not anticipated. Therefore, we analyzed all published FBM-generated e′( t) contours and observed identical agreement. We re-expressed FBM’s algebraic expressions for e′( t) and observed for the first time that model-based predictions for lengthening velocity by the FBM and the PDF model are mathematically identical: e′( t) = γe−α tsinh(β t), thereby providing exact algebraic relations between the three PDF parameters and the six FBM parameters. Previous pioneering experiments have independently established the unique determinants of e′( t) to be LV relaxation, restoring forces (stiffness), and load. In light of the exact intermodel agreement, we conclude that the three PDF parameters, relaxation, stiffness (restoring forces), and load, are unique determinants of DF and e′( t). Thus, we show that only the PDF formalism can compute the three unique, independent, physiological determinants of long-axis LV myocardial velocity from e′( t). NEW & NOTEWORTHY We show that two separate, independently derived physiological (kinematic) models predict mathematically identical expressions for LV-lengthening velocity (Doppler e′-wave), indicating that damped harmonic oscillatory motion is a physiologically accurate model of diastolic function. Although both models predict the same “overdamped” velocity contour, only one model solves the “inverse problem” and generates unique, lumped parameters of relaxation, stiffness (restoring force), and load from the e′-wave.
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McInerney, J. J., R. D. Aronoff, S. H. Blasko, G. L. Copenhaver y M. D. Herr. "Inward diastolic motion: a normal component of isovolumic relaxation and rapid refill". American Journal of Physiology-Heart and Circulatory Physiology 266, n.º 6 (1 de junio de 1994): H2380—H2387. http://dx.doi.org/10.1152/ajpheart.1994.266.6.h2380.
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Many reports note expansive events occurring in the left ventricle during isovolumic relaxation. Expansions during isovolumic relaxation require compensatory inward displacements elsewhere in the ventricle. The location and character of such compensatory displacements have been a continuing source of speculation. Using a high-precision Compton backscatter imaging (CBI) technique, we have detected an early diastolic inward motion that initiates during isovolumic relaxation on the right and left epicardial free walls of the heart in 100% of the 14 normal canines we have studied. This inward motion is first detected 20–30 ms after left ventricular maximal rate of pressure decrease over time (-dP/dtmax), lasts into the early rapid filling phase with a mean duration of 92 +/- 5 (SE) ms, and ends approximately 30 ms after opening of the mitral valve. Maximum wall velocities during this time period (approximately 20 mm/s) exceed those occurring in the same regions during systole. Inward surface displacements in the areas undergoing inward motion average 1.1 +/- 0.2 and 0.9 +/- 0.2 mm on the left and right side of the heart, respectively.
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Seko, Yuta, Takao Kato, Masayuki Shiba, Yusuke Morita, Yuhei Yamaji, Yoshizumi Haruna, Eisaku Nakane, Hideyuki Hayashi, Tetsuya Haruna y Moriaki Inoko. "Association of the low e′ and high E/e′ with long-term outcomes in patients with normal ejection fraction: a hospital population-based observational cohort study". BMJ Open 9, n.º 11 (noviembre de 2019): e032663. http://dx.doi.org/10.1136/bmjopen-2019-032663.
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ObjectiveWe aimed to evaluate the association of the severity of left ventricular (LV) diastolic dysfunction with long-term outcomes in patients with normal ejection fraction.DesignRetrospective study.SettingA single centre in Japan.ParticipantsWe included 3576 patients who underwent both scheduled transthoracic echocardiography and ECG between 1 January and 31 December 2013, in a hospital-based population after excluding valvular diseases or low ejection fraction (<50%) or atrial fibrillation and categorised them into three groups: septal tissue Doppler early diastolic mitral annular velocity (e′)≥7 (without relaxation disorder, n=1593), e′<7 and early mitral inflow velocity (E)/e′≤14 (with relaxation disorder and normal LV end-diastolic pressure, n=1337) and e′<7 and E/e′>14 (with relaxation disorder and high LV end-diastolic pressure, n=646).Primary and secondary outcome measuresThe primary outcome measure was a composite of all-cause death and major adverse cardiac events (MACE). The secondary outcome measure were all-cause death and MACE, separately.ResultsThe cumulative 3-year incidences of the primary outcome measures were significantly higher in the e′<7 and E/e′≤14 (19.0%) and e′<7 and E/e′>14 group (23.4%) than those for the e′≥7 group (13.0%; p<0.001). After adjusting for confounders, the excess 3-year risk of primary outcome for the groups with e′<7 and E/e′≤14 related to e′≥7 (HR: 1.24; 95% CI 1.02 to 1.52) and e′<7 and E/e′>14 related to e′<7 (HR: 1.57; 95% CI 1.28 to 1.94) were significant. The severity of diastolic dysfunction was associated with incrementally higher risk for primary outcomes (p<0.001).ConclusionThe severity of LV diastolic dysfunction using e′<7 and E/e′>14 was associated with the long-term prognosis in patients with normal ejection fraction in an incremental fashion.
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Yelamarty, R. V., R. L. Moore, F. T. Yu, M. Elensky, A. M. Semanchick y J. Y. Cheung. "Relaxation abnormalities in single cardiac myocytes from renovascular hypertensive rats". American Journal of Physiology-Cell Physiology 262, n.º 4 (1 de abril de 1992): C980—C990. http://dx.doi.org/10.1152/ajpcell.1992.262.4.c980.
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In myocardial hypertrophy secondary to renovascular hypertension, the rate of intracellular Ca2+ concentration decline during relaxation in paced left ventricular (LV) myocytes isolated from hypertensive (Hyp) rats is much slower compared with that from normotensive (Sham) rats. By use of a novel liquid-crystal television-based optical-digital processor capable of performing on-line real-time Fourier transformation and the striated pattern (similar to 1-dimensional diffraction grating) of cardiac muscle cells, sarcomere shortening and relaxation velocities were measured in single Hyp and Sham myocytes 18 h after isolation. There were no differences in resting sarcomere length, percent of maximal shortening, time to peak shortening, and average sarcomere shortening velocity between Sham and Hyp cardiac cells. In contrast, average sarcomere relaxation velocity and half-relaxation time were significantly prolonged in Hyp myocytes. Contractile differences between Sham and Hyp myocytes detected by the optical-digital processor are confirmed by an independent method of video tracking of whole cell length changes during excitation-contraction. Despite the fact that freshly isolated myocytes contract more rigorously than 18-h-old myocytes, the relaxation abnormality was still observed in freshly isolated Hyp myocytes, suggesting impaired relaxation is an intrinsic property of Hyp myocytes rather than changes brought about by short-term culture. We postulate that reduced sarcomere relaxation velocity is a direct consequence of impaired Ca2+ sequestration-extrusion during relaxation in Hyp myocytes and may be responsible for diastolic dysfunction in hypertensive hypertrophic myocardium at the cellular level.
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Ece, İbrahim, Serdar Epçaçan, Gülsüm İclal Bayhan y Mehmet Türe. "Diastolic dysfunction in patients with brucellosis despite the absence of infective endocarditis". Cardiology in the Young 30, n.º 12 (16 de septiembre de 2020): 1840–43. http://dx.doi.org/10.1017/s1047951120002930.
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AbstractBackground:Brucellosis is an important systemic infectious disease, especially in developing countries. Every organ and system of the human body can be affected; however, cardiovascular complications of brucellosis are rare.Aim:To assess cardiac functions in patients with acute brucellosis without overt cardiac involvement and to answer the following question: Is there any cardiac dysfunction despite the absence of endocarditis in these patients?Methods:This cross-sectional study included 67 children with brucellosis and 40 healthy children. We performed a detailed echocardiographic examination in individuals at the beginning of the treatment. Patients with infective endocarditis were excluded from the study.Results:Echocardiography revealed no difference of ejection fraction, mitral and tricuspid annular plane systolic excursion, pulsed-wave Doppler-derived early diastolic peak velocity (E)/late diastolic peak velocity (A) ratios in mitral and tricuspid valves between the two groups. The deceleration time of early mitral inflow was longer in patients with brucellosis. Early diastolic peak velocity of the mitral and tricuspid annuluses obtained by tissue Doppler imaging (Ea) was significantly lower in children with brucellosis. The peak velocity obtained by tissue Doppler imaging during late diastole (Aa), Ea and Ea/Aa ratios in the interventricular septum, left ventricle posterior wall and right ventricle free wall was lower in patients with brucellosis than in the control group. The E/Ea ratio, isovolumic relaxation time, right ventricle and left ventricle myocardial performance indices were higher in patients with brucellosis.Conclusion:Patients with acute brucellosis may have diastolic dysfunction without overt cardiac involvement and infective endocarditis.
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Wang, Zhibin, Fereshteh Jalali, Yi-Hui Sun, Jiun-Jr Wang, Kim H. Parker y John V. Tyberg. "Assessment of left ventricular diastolic suction in dogs using wave-intensity analysis". American Journal of Physiology-Heart and Circulatory Physiology 288, n.º 4 (abril de 2005): H1641—H1651. http://dx.doi.org/10.1152/ajpheart.00181.2004.
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Two apparently different types of mechanisms have emerged to explain diastolic suction (DS), that property of the left ventricle (LV) that tends to cause it to refill itself during early diastole independent of any force from the left atrium (LA). By means of the first mechanism, DS depends on decreased elastance [e.g., the relaxation time constant (τ)] and, by the second, end-systolic volume (VLVES). We used wave-intensity analysis (WIA) to measure the total energy transported by the backward expansion wave ( IW−) during LV relaxation in an attempt to reconcile these mechanisms. In six anesthetized, open-chest dogs, we measured aortic, LV (PLV), LA (PLA), and pericardial pressures and LV volume by orthogonal ultrasonic crystals. Mitral velocity was measured by Doppler echocardiography, and aortic velocity was measured by an ultrasonic flow probe. Heart rate was controlled by pacing, VLVES by volume loading, and τ by isoproterenol or esmolol administration. IW− was found to be inversely related to τ and VLVES. Our measure of DS, the energy remaining after mitral valve opening, IW−DS, was also found to be inversely related to τ and VLVES and was ∼10% of the total “aspirating” energy generated by LV relaxation (i.e., IW−). The size of the Doppler (early filling) E wave depended on IW−DS in addition to IW+, the energy associated with LA decompression. We conclude that the energy of the backward-going wave generated by the LV during relaxation depends on both the rate at which elastance decreases (i.e., τ) and VLVES. WIA provides a new approach for assessing DS and reconciles those two previously proposed mechanisms. The E wave depends on DS in addition to LA decompression.
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Hees, Paul S., Jerome L. Fleg, Sheng-Jing Dong y Edward P. Shapiro. "MRI and echocardiographic assessment of the diastolic dysfunction of normal aging: altered LV pressure decline or load?" American Journal of Physiology-Heart and Circulatory Physiology 286, n.º 2 (febrero de 2004): H782—H788. http://dx.doi.org/10.1152/ajpheart.01092.2002.
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Changes in diastolic indexes during normal aging, including reduced early filling velocity ( E), lengthened E deceleration time (DT), augmented late filling ( A), and prolonged isovolumic relaxation time (IVRT), have been attributed to slower left ventricular (LV) pressure (LVP) decay. Indeed, this constellation of findings is often referred to as the “abnormal relaxation” pattern. However, LV filling is determined by the atrioventricular pressure gradient, which depends on both LVP decline and left atrial (LA) pressure (LAP). To assess the relative influence of LVP decline and LAP, we studied 122 normal subjects aged 21–92 yr by Doppler echocardiography and MRI. LVP decline was assessed by color M-mode ( Vp) and the LV untwisting rate. Early diastolic LAP was evaluated using pulmonary vein flow systolic fraction, pulmonary vein flow diastolic DT, color M-mode ( E/ Vp), and tissue Doppler ( E/ Em). Linear regression showed the expected reduction of E, increase in A, and prolongation of IVRT and DT with advancing age. There was no relation of age to parameters reflecting the rate of LVP decline. However, older age was associated with reduced E/ Vp ( P = 0.008) and increased pulmonary vein systolic fraction ( P < 0.001), pulmonary vein DT ( P = 0.0026), and E/ Em ( P < 0.0001), all suggesting reduced early LAP. Therefore, reduced early filling in older adults may be more closely related to a reduced early diastolic LAP than to slower LVP decline. This effect also explains the prolonged IVRT. We postulate that changes in LA active or passive properties may contribute to development of the abnormal relaxation pattern during the aging process.
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Bondar', Irina Arkad'evna, Alexander Aristarkhovich Demin y Olesya Yur'evna Shabel'nikova. "Morphological and functional parameters of the heart and vessels in patients with type 2 diabetes mellitus and cardiovascular autonomic neuropathy". Diabetes mellitus 17, n.º 2 (21 de abril de 2014): 41–46. http://dx.doi.org/10.14341/dm2014241-46.
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Objective. To evaluate morphological and functional parameters of the heart and vessels in patients with type 2 diabetes mellitus (DM2) and diabetic cardiovascular autonomic neuropathy (CAN). Materials and methods. A total of 139 patients with DM2 and hypertension (mean age: 53.1?4.9 years; mean duration of hypertension: 9.7?7.8 years) were included in this study. Based on cardiovascular autonomic function test results (electrocardiography, heart rate variability) patients were divided into 2 groups as follows: Group 1 included 40 patients without CAN and Group 2 included 99 patients with CAN. The control group comprised 30 patients with hypertension and normal carbohydrate metabolism (mean age: 53.1?6.0 years; mean duration of hypertension: 10.9?8.5 years). All patients underwent ultrasonography of the heart and common carotid artery. Results. Group 2 patients showed a significant decrease in maximal transmitral flow velocity during early diastolic filling (0.61?0.12 m/s) and a decrease in maximal transmitral flow velocity during late diastolic filling (0.65?0.11 m/s) compared with Group 1 patients (0.66?0.09 m/s and 0.69?0.09 m/s, respectively, р
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Popović, Zoran B., Milind Y. Desai, Adisai Buakhamsri, Chirapa Puntawagkoon, Allen Borowski, Benjamin D. Levine, Wilson W. H. Tang y James D. Thomas. "Predictors of mitral annulus early diastolic velocity: impact of long-axis function, ventricular filling pattern, and relaxation". European Heart Journal - Cardiovascular Imaging 12, n.º 11 (23 de agosto de 2011): 818–25. http://dx.doi.org/10.1093/ejechocard/jer146.
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Okada, K., T. Mikami, S. Kaga, H. Onozuka, M. Inoue, S. Yokoyama, H. Nishino et al. "Early diastolic mitral annular velocity at the interventricular septal annulus correctly reflects left ventricular longitudinal myocardial relaxation". European Journal of Echocardiography 12, n.º 12 (9 de septiembre de 2011): 917–23. http://dx.doi.org/10.1093/ejechocard/jer154.
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Zeybek, Cenap, Vildan Tasyenen, Elif Kazanci y Aysun Boga. "Evaluation of cardiac function in healthy children native to 1890 metres". Cardiology in the Young 20, n.º 2 (15 de marzo de 2010): 201–5. http://dx.doi.org/10.1017/s1047951110000156.
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AbstractObjectiveThe aim of the study is, by comparing cardiac parameters between children native to 1890 metres with children living at sea level, to find out whether there is any impairment in cardiac function related to that altitude.MethodsElectrocardiographic, conventional, and tissue Doppler echocardiographic parameters were compared in 42 healthy children native to 1890 metres, and in 21 healthy age and gender matched children living at sea level. Plasma haemoglobin level and oxygen saturation measured by pulse oxymeter were also obtained from all patients.ResultsHaemoglobin levels were higher, and oxygen saturation levels were lower in children native to 1890 metres. Conventional echocardiographic parameters and mitral annular myocardial parameters were all similar between children native to 1890 metres and children living at sea level. Tricuspid lateral annular early diastolic velocity and the ratio of early-to-late diastolic velocity were significantly lower and tricuspid lateral annular izovolumetric relaxation time was significantly higher in children native to 1890 metres than children living at sea level.ConclusionChildren living at 1890 metres of altitude predispose to asymptomatic right ventricular diastolic dysfunction or otherwise they remain as healthy children.
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Weber, Howard S. "Serial echocardiographic Doppler evaluation of diastolic function in the normal human fetus". Cardiology in the Young 6, n.º 1 (enero de 1996): 32–36. http://dx.doi.org/10.1017/s1047951100003218.
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AbstractThe assessment of diastolic function in the developing fetus is difficult because of constantly changing conditions of loading. Previous reports suggesting improved ventricular compliance with fetal development are limited by the Doppler indices utilized. Using load-dependent and independent variables, we examined and compared serially right and left ventricular diastolic function in 11 normal fetuses (44 echocardiographic studies) at 22±1.0 weeks; 30±1.0 weeks; 36±1.0 weeks of gestation and 64±25 hours postnatally. Load-dependent indices included early to late time velocity integral ratios and percentage of early filling to total diastolic filling. The load-independent index was the peak filling rate normalized to the total time velocity integral. Both right and left ventricular time velocity integral ratios were similar initially, and shifted from late to early diastole with increasing gestational age (greater ratios). The shift in left ventricular ratios was greater, and increased earlier in fetal development. The right ventricular normalized peak filling rate decreased with increasing gestational age, while the left ventricular normalized peak filling rate remained constant, but was greater than the right ventricular rate postnatally. Both right and left ventricular filling shifts from late “active” to early “passive” diastole during fetal development. Left ventricular ratios are greater and increase earlier in fetal development, likely influenced by changes in preload. The right and left ventricular normalized peak filling rates were similar prenatally, indicating similar diastolic filling properties, but disparate postnatally, consistent with improved left ventricular relaxation immediately preceding or at the time of onset of transitional circulation.
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Wolska, B. M., M. O. Stojanovic, W. Luo, E. G. Kranias y R. J. Solaro. "Effect of ablation of phospholamban on dynamics of cardiac myocyte contraction and intracellular Ca2+". American Journal of Physiology-Cell Physiology 271, n.º 1 (1 de julio de 1996): C391—C397. http://dx.doi.org/10.1152/ajpcell.1996.271.1.c391.
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We compared mechanical activity and Ca2+ transients of ventricular myocytes isolated from wild-type and phospholamban (PLB)-deficient mouse hearts in control conditions and during beta-adrenergic stimulation. Compared with wild-type controls, cells isolated from PLB-deficient mouse hearts showed 1) a 2-fold increase in extent of cell shortening, 2) a 3-fold increase in maximal shortening velocity, and 3) a 3.4-fold increase in maximal relengthening velocity. PLB-deficient myocytes also demonstrated significant increases in the peak amplitude of the fura 2 fluorescence ratio and the rates of rising and falling phases of the Ca2+ transient. The fura 2 diastolic ratios were similar in both groups, suggesting no change in intracellular Ca2+ during diastole. In PLB-deficient myocytes, 0.05 microM isoproterenol induced an increase in the twitch amplitude by 152 +/- 11% (n = 6) compared with 290 +/- 31% (n = 6) in wild-type cells. Maximal shortening velocity was increased by 183 +/- 10% (n = 6) in PLB-deficient myocytes, compared with 398 +/- 62% (n = 6) in wild-type cells. The isoproterenol-induced increase in maximum relengthening velocity was increased by 168 +/- 8% (n = 6) in PLB-deficient cells compared with 445 +/- 71% (n = 6) in wild-type myocytes. In both groups, these changes in contractile parameters were accompanied by changes in the Ca2+ transient. Our results indicate that phosphorylation of sites other than PLB may play an important role in regulation of contraction-relaxation dynamics of heart cells responding to beta-adrenergic stimulation.
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You, Jieyun, Jian Wu, Junbo Ge y Yunzeng Zou. "Comparison between adenosine and isoflurane for assessing the coronary flow reserve in mouse models of left ventricular pressure and volume overload". American Journal of Physiology-Heart and Circulatory Physiology 303, n.º 10 (15 de noviembre de 2012): H1199—H1207. http://dx.doi.org/10.1152/ajpheart.00612.2012.
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Adenosine and high-concentration isoflurane are commonly used to induce hyperemia for assessment of coronary flow reserve (CFR) in mice, but high-concentration isoflurane may exacerbate cardiac dysfunction, leading to impaired CFR. However, there is no study be found comparing the effects of adenosine and isoflurane on CFR and corresponding cardiac function. High-resolution echocardiography and invasive hemodynamic assessment were performed in 20 mice 2 wk after transverse aortic constriction (TAC), aortic regurgitation (AR), and corresponding sham operation. CFR was calculated as the ratio of hyperemic to basal peak diastolic velocity (CFRpdv) or diastolic velocity-time integral (CFRdvti). In the sham-operated mice, no differences were observed between the effects of adenosine and isoflurane on CFR, left ventricular systolic function (left ventricular ejection fraction and fractional shortening), left ventricular end-systolic pressure, maximal contraction and relaxation velocity (+dp/d t and −dp/d t), alteration of left ventricular pressure (ΔLVP), or ± dp/d t (Δdp/d t). But adenosine-derived results were significantly higher than isoflurane-derived ones in both the TAC and the AR groups. Moreover, CFRpdv or CFRdvti was positively correlated with both LVEF and LVFS. Compared with adenosine-derived CFR, isoflurane-derived CFR may be underestimated in the TAC and the AR mice, which is probably associated with suppressed cardiac function.
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Yamaguchi, K., Y. Miyahara, K. Yakabe, T. Kiya, M. Nakatomi, M. Shikuwa y S. Kohno. "Right Ventricular Impairment in Patients with Chronic Respiratory Failure on Home Oxygen Therapy — Non-Invasive Assessment Using a New Doppler Index". Journal of International Medical Research 26, n.º 5 (octubre de 1998): 239–47. http://dx.doi.org/10.1177/030006059802600503.
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We evaluated the usefulness of the newly defined Doppler index combining systolic and diastolic myocardial performance, in assessing right-heart dysfunction in 29 patients with chronic respiratory failure caused by old tuberculosis who were on 24-h home oxygen therapy. We measured tricuspid inflow velocity, right-ventricular outflow velocity, late/early diastolic peak velocities (A/E), the ratio between pre-ejection period and ejection time (PEP/ET), and the new index of systolic and diastolic myocardial performance (SDMP) calculated as (isovolumetric contraction time + isovolumetric relaxation time)/ejection time. The calculated A/E, PEP/ET and SDMP in our patients were significantly higher than those in age-matched healthy subjects ( n = 37, mean age 67 ± 8 years). There was no overlap in the SDMP index between healthy subjects and patients and the index was not influenced by heart rate. Our results suggest that SDMP index is a better marker than A/E and PEP/ET for the assessment of right-ventricular impairment.
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Lemmon, Jack D. y Ajit P. Yoganathan. "Computational Modeling of Left Heart Diastolic Function: Examination of Ventricular Dysfunction". Journal of Biomechanical Engineering 122, n.º 4 (22 de marzo de 2000): 297–303. http://dx.doi.org/10.1115/1.1286559.
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A computational model that accounts for blood–tissue interaction under physiological flow conditions was developed and applied to a thin-walled model of the left heart. This model consisted of the left ventricle, left atrium, and pulmonary vein flow. The input functions for the model included the pulmonary vein driving pressure and time-dependent relationship for changes in chamber tissue properties during the simulation. The Immersed Boundary Method was used for the interaction of the tissue and blood in response to fluid forces and changes in tissue pathophysiology, and the fluid mass and momentum conservation equations were solved using Patankar’s Semi-Implicit Method for Pressure Linked Equations (SIMPLE). This model was used to examine the flow fields in the left heart under abnormal diastolic conditions of delayed ventricular relaxation, delayed ventricular relaxation with increased ventricular stiffness, and delayed ventricular relaxation with an increased atrial contraction. The results obtained from the left heart model were compared to clinically observed diastolic flow conditions, and to the results from simulations of normal diastolic function in this model 1. Cases involving impairment of diastolic function were modeled with changes to the input functions for fiber relaxation/contraction of the chambers. The three cases of diastolic dysfunction investigated agreed with the changes in diastolic flow fields seen clinically. The effect of delayed relaxation was to decrease the early filling magnitude, and this decrease was larger when the stiffness of the ventricle was increased. Also, increasing the contraction of the atrium during atrial systole resulted in a higher late filling velocity and atrial pressure. The results show that dysfunction can be modeled by changing the relationships for fiber resting-length and/or stiffness. This provides confidence in future modeling of disease, especially changes to chamber properties to examine the effect of local dysfunction on global flow fields. [S0148-0731(00)00104-7]
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Areias, Jose C., William A. Scott, Robin Meyer y Stanley J. Goldberg. "A serial Doppler echocardigraphic study of early diastolic right ventricular events in full term neonates". Cardiology in the Young 2, n.º 1 (enero de 1992): 20–24. http://dx.doi.org/10.1017/s1047951100000536.
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SummaryOur purpose was to study serially, measurements which relate to right ventricular events, using echocardiography and Doppler in full term neonates for the first three weeks after birth. Echocardiographic and pulsed Doppler studies were performed for 21 newborns during the first 36 hours of life, and subsequent serial studies were performed in the second (n=21) and third (n=14) weeks of life. Evaluation included measurement of right isovolumic relaxation time and peak E and A velocities across the tricuspid valve. Pulmonary velocities were studied for evidence of patency of the arterial duct, and to determine acceleration in the pulmonary trunk. Mean right isovolumic relaxation time decreased significantly from 68±9 ms to 39 ± 14 ms (p<0.001) between the first and second week. Mean tricuspid peak E increased significantly between the second (48 ± 7 cm/s) and the third week of life (62 ± 8 cm/s; p<0.001). Mean peak A wave velocity did not change significantly during the time of study. The pulmonary arterial acceleration time increased from the initial measurement (68 ± 10 ms) to the second week (85 ± 9 ms; p<0.001). Changes in right isovolumic relaxation time were significantly related to the changes in the pulmonary arterial acceleration time (r=0.63, p=0.0001), suggesting a significant influence of afterload on diastolic events. These data demonstrate the normal progression of some measures of early right ventricular diastolic function.
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Vierendeels, J. A., K. Riemslagh, E. Dick y P. R. Verdonck. "Computer Simulation of Intraventricular Flow and Pressure Gradients During Diastole". Journal of Biomechanical Engineering 122, n.º 6 (9 de julio de 2000): 667–74. http://dx.doi.org/10.1115/1.1318941.
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A two-dimensional axisymmetric computer model is developed for the simulation of the filling flow in the left ventricle (LV). The computed results show that vortices are formed during the acceleration phases of the filling waves. During the deceleration phases these are amplified and convected into the ventricle. The ratio of the maximal blood velocity at the mitral valve (peak E velocity) to the flow wave propagation velocity (WPV) of the filling wave is larger than 1. This hemodynamic behavior is also observed in experiments in vitro (Steen and Steen, 1994, Cardiovasc. Res., 28, pp. 1821–1827) and in measurements in vivo with color M-mode Doppler echocardiography (Stugaard et al., 1994, J. Am. Coll. Cardiol., 24, 663–670). Computed intraventricular pressure profiles are similar to observed profiles in a dog heart (Courtois et al., 1988, Circulation, 78, pp. 661–671). The long-term goal of the computer model is to study the predictive value of noninvasive parameters (e.g., velocities measured with Doppler echocardiography) on invasive parameters (e.g., pressures, stiffness of cardiac wall, time constant of relaxation). Here, we show that higher LV stiffness results in a smaller WPV for a given peak E velocity. This result may indicate an inverse relationship between WPV and LV stiffness, suggesting that WPV may be an important noninvasive index to assess LV diastolic stiffness, LV diastolic pressure and thus atrial pressure (preload). [S0148-0731(00)01606-X]
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Zhou, Yu-Qing, F. Stuart Foster, Robert Parkes y S. Lee Adamson. "Developmental changes in left and right ventricular diastolic filling patterns in mice". American Journal of Physiology-Heart and Circulatory Physiology 285, n.º 4 (octubre de 2003): H1563—H1575. http://dx.doi.org/10.1152/ajpheart.00384.2003.
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Developmental changes in left and right ventricular diastolic filling patterns were determined noninvasively in isoflurane-anesthetized outbred ICR mice. Blood velocities in the mitral and tricuspid orifices were recorded in 16 embryos at days 14.5 (E14.5) and 17.5 of gestation (E17.5) using an ultrasound biomicroscope and also serially in three groups of postnatal mice aged 1–7 days ( n = 23), 1–4 wk ( n = 18), and 4–12 wk ( n = 27) using 20-MHz pulsed Doppler. Postnatal body weight increased rapidly to 8 wk. Heart rate increased rapidly from ∼180 beats/min at E14.5 to ∼380 beats/min at 1 wk after birth and then more gradually to plateau at ∼450 beats/min after 4 wk. Ventricular filling was quantified using the ratio of peak velocity of early ventricular filling due to active relaxation (E wave) to that of the late ventricular filling caused by atrial contraction (A wave) (peak E/A ratio) and the ratio of the peak E velocity to total time-velocity integral of E and A waves (peak E/total TVI ratio). Both ventricles had similar diastolic filling patterns in embryos (peak E/A ratio of 0.28 ± 0.02 for mitral flow and 0.27 ± 0.02 for tricuspid flow at E14.5). After birth, mitral peak E/A increased to >1 between the third and fifth day, continued to increase to 2.25 ± 0.25 at ∼3 wk, and then remained stable. The tricuspid peak E/A ratio increased much less but stabilized at the same age (increased to 0.79 ± 0.03 at 3 wk). The peak E/total TVI ratio showed similar left-right differences and changes with development. Age-related changes were largely due to increases in peak E velocity. The results suggest that diastolic function matures ∼3 wk postnatally, presumably in association with maturation of ventricular recoil and relaxation mechanisms.
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Remme, Espen W., Anders Opdahl y Otto A. Smiseth. "Mechanics of left ventricular relaxation, early diastolic lengthening, and suction investigated in a mathematical model". American Journal of Physiology-Heart and Circulatory Physiology 300, n.º 5 (mayo de 2011): H1678—H1687. http://dx.doi.org/10.1152/ajpheart.00165.2010.
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We investigated the determinants of ventricular early diastolic lengthening and mechanics of suction using a mathematical model of the left ventricle (LV). The model was based on a force balance between the force represented by LV pressure (LVP) and active and passive myocardial forces. The predicted lengthening velocity ( e′) from the model agreed well with measurements from 10 dogs during 5 different interventions ( R = 0.69, P < 0.001). The model showed that e′ was increased when relaxation rate and systolic shortening increased, when passive stiffness was decreased, and when the rate of fall of LVP during early filling was decreased relative to the rate of fall of active stress. We first defined suction as the work the myocardium performed to pull blood into the ventricle. This occurred when contractile active forces decayed below and became weaker than restoring forces, producing a negative LVP. An alternative definition of suction is filling during falling pressure, commonly believed to be caused by release of restoring forces. However, the model showed that this phenomenon also occurred when there had been no systolic compression below unstressed length and therefore in the absence of restoring forces. In conclusion, relaxation rate, LVP, systolic shortening, and passive stiffness were all independent determinants of e′. The model generated a suction effect seen as lengthening occurring during falling pressure. However, this was not equivalent with the myocardium performing pulling work on the blood, which was performed only when restoring forces were higher than remaining active fiber force, corresponding to a negative transmural pressure.
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Brothers, R. Matthew, Paul S. Bhella, Shigeki Shibata, Jonathan E. Wingo, Benjamin D. Levine y Craig G. Crandall. "Cardiac systolic and diastolic function during whole body heat stress". American Journal of Physiology-Heart and Circulatory Physiology 296, n.º 4 (abril de 2009): H1150—H1156. http://dx.doi.org/10.1152/ajpheart.01069.2008.
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During a whole body heat stress, stroke volume is either maintained or slightly elevated despite reduced ventricular filling pressures and central blood volume, suggestive of improved cardiac diastolic and/or systolic function. Heat stress improves cardiac systolic and diastolic function in patients with congestive heart failure, although it remains unknown whether similar responses occur in healthy individuals, which is the hypothesis to be tested. Nine male volunteers underwent a whole body heat stress. Echocardiographic indexes of diastolic and systolic function were performed following a supine resting period, and again following an increase in internal temperature of ∼1.0°C via passive heat stress. Despite previous reports of heat stress-induced decreases in ventricular filling pressures and central blood volume, no changes in indexes of diastolic function were identified during heating [i.e., unchanged early diastolic mitral annular tissue velocity (E′), mitral inflow during the early diastolic phase (E), the E/E′ ratio, and isovolumetric relaxation time]. Heat stress increased late diastolic septal ( P = 0.03) and lateral ( P = 0.01) mitral annular tissue velocities (A′), mitral inflow velocity during atrial contraction ( P < 0.001), and the relative contribution of atrial contraction to left ventricular filling during diastole ( P = 0.01), all indicative of improved atrial systolic function. Furthermore, indexes of ventricular systolic function were increased by heat stress [i.e., increased septal ( P = 0.001) and lateral ( P = 0.01) mitral annular systolic velocities and isovolumic acceleration at the septal ( P = 0.03) and lateral ( P < 0.001) mitral annulus]. These data are suggestive of improved atrial and ventricular systolic function by the heat stress. Together these data support previous findings, which used the less precise measure of ejection fraction, that heat stress improves indexes of systolic function, while diastolic function is maintained.
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Arigondam, Ashok, Vara Prasad y Liza Rajasekhar. "Role of Tissue Doppler Echocardiography in the Diagnosis of Early Left Ventricular Dysfunction in Rheumatoid Arthritis". Indian Journal of Cardiovascular Disease in Women WINCARS 01, n.º 02 (junio de 2016): 017–21. http://dx.doi.org/10.1055/s-0038-1656399.
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AbstractObjective: Rheumatoid arthritis (RA) is a systemic disease involving many organ systems and is frequently accompanied by cardiac alterations. The purpose of our study is the usefulness of Tissue Doppler echocardiography to detect the nature and extent of cardiac involvement in RA patients with no symptoms of cardiac disease, in comparison with a control sample.Methods: We selected 21 patients affected by rheumatoid arthritis. No patient had any symptoms of cardiac disease. As a control group we studied 21 volunteers, randomly selected among a larger group of subjects who had come for routine check-up. All were in sinus rhythm and without any cardiac symptom. Standard two-dimensional, M-mode and Doppler echocardiographic examination was carried out on each subject.Results: out of 21 RA patients, 16 females 5 males with an average age of 38±9 years. Both the study group and control were matched with respect to age and sex. In RA patients we found a higher prevalence of several tissue Doppler parameters abnormalities. Patients with RA showed significantly higher tricuspid annular plane systolic ejection (TAPSE) 2.49±0.19 vs. 2.36±0.22 (p= 0.04), isovolumetric contraction time (IVCT) 48.8±11.7 vs. 41.2±7.7 msec, (p=0.02), isovolumetric velocity (IVV) 12.26±2.23 vs. 15.71±1.89 m/sec ( p = 0.00) acceleration time (AT) 0.43±0.05 vs. 0.35+0.05 msec (p = 0.00) lower isovolumetric acceleration (IVA) 28.68±6.57 vs. 45.8±10.1 m/sec2 (p = 0.00) early diastolic velocity (E)′ 10.48±1.99 vs. 13.02±1.54 cm/sec (p = 0.00). No significant difference was noted with IVRT (isovolumetric relaxation time) and A′ (late diastolic velocity). Duration of RA did not affect the significance of these parameters.Conclusion: There was subclinical LV systolic and diastolic dysfunction with normal EF, detected by tissue Doppler imaging in Rheumatoid arthritis patients.
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Acharya, Ganesh, James C. Huhta, Mervi Haapsamo, Ole-Jakob How, Tiina Erkinaro y Juha Räsänen. "Effect of Angiotensin II on the Left Ventricular Function in a Near-Term Fetal Sheep with Metabolic Acidemia". Journal of Pregnancy 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/634240.
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We tested the hypothesis that, in acute metabolic acidemia, the fetal left ventricle (LV) has the capacity to increase its contractility in response to angiotensin II infusion. Eleven ewes and their fetuses were instrumented at 127–138/145 days of gestation. The effect of angiotensin II on fetal LV function was assessed using intraventricular pressure catheter and tissue Doppler imaging (TDI). Angiotensin II increased fetal arterial blood pressure, whereas pH and pO2decreased. The heart rate and systemic venous pressure were not affected significantly. The LV end-diastolic and end-systolic pressures, as well asdP/dtmax, increased. The TDI-derived LV longitudinal myocardial isovolumic contraction velocity and its acceleration and velocity during early filling were higher than those at baseline. The incidence of absent isovolumic relaxation velocity was greater during angiotensin II infusion. In summary, during acute metabolic acidemia, the fetal left ventricle could increase its contractility in response to inotropic stimulus even in the presence of increased afterload. The diastolic LV function parameters were altered by angiotensin II.
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Ingle, Vijaykumar V. "Study of diastolic dysfunction in essential hypertension patients in relation to age and duration of treatment". International Journal of Advances in Medicine 4, n.º 5 (22 de septiembre de 2017): 1447. http://dx.doi.org/10.18203/2349-3933.ijam20174301.
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Background: Hypertension is a major health problem worldwide and its complications have significant socioeconomic impact. The objective of this study was to evaluate diastolic dysfunction (DD) in essential hypertension patients and the influence of age and duration of hypertension on this parameter.Methods: One hundred essential hypertensive patients (HT) underwent Doppler echocardiography to obtain E/A wave ratio (E/A), atrial deceleration time (ADT), isovolumetric relaxation time (IRT) and Tissue Doppler early diastolic mitral annular velocity (E). All patients were grouped according to age at diagnosis of hypertension and duration of the disease.Results: A higher prevalence of DD occurred parallel to age and duration of the disease.Conclusions: DD was prevalent in this hypertensive population, being highly affected by age and DD is observed in incipient stages of hypertensive heart disease, and thus its early detection may help in the risk stratification of hypertensive patients.
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Riordan, Matt M., Edward P. Weiss, Timothy E. Meyer, Ali A. Ehsani, Susan B. Racette, Dennis T. Villareal, Luigi Fontana, John O. Holloszy y Sándor J. Kovács. "The effects of caloric restriction- and exercise-induced weight loss on left ventricular diastolic function". American Journal of Physiology-Heart and Circulatory Physiology 294, n.º 3 (marzo de 2008): H1174—H1182. http://dx.doi.org/10.1152/ajpheart.01236.2007.
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Little is known about the effects of weight loss on diastolic function. Furthermore, it is not known whether both caloric restriction (CR)- and exercise (Ex)-induced weight loss have salutary effects on diastolic function. Therefore, we assessed the effects of yearlong CR ( n = 12) and Ex ( n = 13) interventions, which induced ∼12% weight loss, on diastolic function in healthy, nonobese (body mass index = 23.5–29.9 kg/m2) men and women aged 50 to 60 yr. Recordings of Doppler transmitral flow and Doppler tissue imaging were acquired and analyzed by conventional approaches and a validated parameterized diastolic filling (PDF) formalism. Isovolumic relaxation time decreased after weight loss in both groups ( P < 0.05). Septal peak early mitral annular velocity (E′) increased ( P < 0.01) and peak E-wave velocity/E′ decreased ( P < 0.05) after weight loss in the CR group. Based on the PDF-derived indexes, CR resulted in a decrease in global ventricular stiffness ( k) and increases in longitudinal (septal annulus motion) stored elastic strain ( x′o), peak force ( k′ x′o), and peak stored strain energy (1/2 k′ xoprime;2). In the Ex group, k was unchanged, although septal x′o and 1/2 k′ xo′2 increased significantly and k′ x′o ( P = 0.13) tended to increase. We conclude that weight loss, whether induced by CR or Ex, has salutary effects on diastolic function.
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JENSEN, Jens, Lars-Åke BRODIN, Britta LIND, Sven V. ERIKSSON, Mats JENSEN-URSTAD y Christer SYLVÉN. "Deterioration in peak systolic velocity is closely related to ischaemia during angioplasty: a vectorcardiographic and tissue Doppler imaging study". Clinical Science 100, n.º 2 (20 de diciembre de 2000): 137–43. http://dx.doi.org/10.1042/cs1000137.
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We tested the hypothesis that the extent of signs of ischaemia detected by vectorcardiography (VCG) during elective coronary angioplasty (percutaneous transluminal coronary angioplasty; PTCA) is related to systolic and diastolic myocardial velocities, as determined by tissue Doppler echocardiography. A total of 15 patients undergoing PTCA (12 men/three women; age 61±9 years), without prior myocardial infarction and with an ejection fraction of > 50%, were included. The balloon inflation was repeated three times, with minimum intervals of 2 min between inflations. Tissue Doppler echocardiography was performed, in an apical two- or four-chamber view, before and at the end of each inflation. Peak systolic velocity, time-to-peak systolic velocity (TTP), peak early (Em) and late (Am) diastolic velocities, the Em/Am ratio and isovolumic relaxation time were measured in the basal segments of the left ventricle. VCG recordings were carried out during the whole procedure. ST vector magnitude (ST-VM) and ST change vector magnitude (STC-VM) were monitored. The total duration and area of each VCG change during inflation were calculated for each patient. Isovolumic relaxation time, peak Em and Am values and the Em/Am ratio did not change significantly during inflation. Peak systolic velocity decreased (6.7±2.0 to 5.3±1.9 cm/s; P < 0.001) and TTP increased (157±60 to 192±60 ms; P < 0.01) during inflation. Both STC-VM time (r = -0.68, P < 0.01) and STC-VM area (r = -0.68, P < 0.01) were related to peak systolic velocity during inflation. STC-VM time was also related (r = 0.55, P < 0.05) to the difference in peak systolic velocity during compared with before inflation. ST-VM was less closely related to peak systolic velocity. Thus the duration and degree of ischaemia, as measured by VCG, are related to peak systolic velocity in the basal segments of the left ventricle.
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Zhang, Haibin, Yunqiu Qian, Hongling Li, Yan Song, Xiaodong Zhou, Ting Zhu, Yongsheng Zhu, Xinqiao Tian y Jun Zhang. "Early diastolic peak velocity of left ventricular wall segment lying in isovolumic relaxation period as determined by tissue Doppler imaging". International Journal of Cardiovascular Imaging 24, n.º 4 (23 de octubre de 2007): 389–97. http://dx.doi.org/10.1007/s10554-007-9276-y.
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