Patterns of diastolic dysfunction in left ventricular hypertrophy

Associations of Traditionally Determined Left Ventricular Mass Indices and Hemodynamic and Non-Hemodynamic Components of Cardiac Remodeling with Diastolic and Systolic Function in Patients with Chronic Kidney Disease

We aimed to evaluate the extent to which different left ventricular mass parameters are associated with left ventricular function in chronic kidney disease (CKD) patients. We compared the associations between traditionally determined left ventricular mass indices (LVMIs) and hemodynamic (predicted LVMIs) and non-hemodynamic remodeling parameters with left ventricular function in patients with CKD; non-hemodynamic remodeling was represented by inappropriate left ventricular mass and inappropriate excess LVMIs (traditionally determined LVMIs-predicted LVMIs). Non-hemodynamic left ventricular remodeling parameters were strongly associated with impaired left ventricular systolic function (p < 0.001), whereas hemodynamic left ventricular remodeling was also related strongly (p < 0.001) but directly to left ventricular systolic function. Independent of one another, hemodynamic and non-hemodynamic left ventricular remodeling had associations in opposite directions to left ventricular systolic function and was associated directly with traditionally determined left ventricular mas indices (p < 0.001 for all relationships). Non-hemodynamic cardiac remodeling parameters discriminated more effectively than traditionally determined LVMIs between patients with and without reduced ejection fraction (p < 0.04 for comparison). Left ventricular mass parameters were unrelated to impaired diastolic function in patients with CKD. Traditionally determined LVMIs are less strongly associated with impaired systolic function than non-hemodynamic remodeling parameters (p < 0.04-0.01 for comparisons) because they represent both adaptive or compensatory and non-hemodynamic cardiac remodeling.

Let there be light! The meteoric rise of cardiac imaging

Imaging plays a central role in modern cardiovascular practice. It is a field characterised by exciting technological advances that have shaped our understanding of pathology and led to major improvements in patient diagnosis and care. The UK has played a key international role in the development of this subspecialty and is the current home to many of the leading global centres in multimodality cardiovascular imaging. In this short review, we will outline some of the key contributions of the British Cardiovascular Society and its members to this rapidly evolving field and look at how this relationship may continue to shape future cardiovascular practice.

Dietary normalization from a fat, fructose and cholesterol-rich diet to chow limits the amount of myocardial collagen in a Göttingen Minipig model of obesity

Background

Dietary interventions have been shown to attenuate some of the myocardial pathological alterations associated with obesity. This study evaluated the effect of dietary normalization from a fat/fructose/cholesterol-rich diet to chow on left ventricular (LV) myocardial fibrosis, fat infiltration and hypertrophy but also the specific influence of obesity, plasma lipids and glucose metabolism markers on heart morphology in a Göttingen Minipig model of obesity.

Methods

Forty castrated male Göttingen Minipigs were assigned to three groups fed either standard minipig chow (SD, n = 8) for 13 months, fat/fructose/cholesterol-rich diet (FFC, n = 16) for 13 months or fat/fructose/cholesterol-rich diet for 7 months and then changed to standard minipig chow for the remaining 6 months (FFC/SD, n = 16). Body weight, body fat percentage, plasma lipids and glucose metabolism markers were evaluated in all three groups after 6–7 months (prior to diet adjustment for FFC/SD) and again before termination. Further, biochemical quantification of myocardial collagen and triglyceride content, semi-quantitative histological evaluation of fibrosis and fat infiltration and quantitative histological analysis of collagen and cardiomyocyte diameter were performed and heart weight was obtained after termination. Group differences were evaluated using Kruskal-Wallis test and Fisher’s exact test for categorical variables. Pearson correlation analysis was performed to test for correlations between myocardial changes and selected explanatory variables. For non-parametric response variables, a Spearman correlation analysis was applied.

Results

Myocardial collagen content quantified biochemically was significantly lower in FFC/SD compared to FFC (P = 0.02). Furthermore, dietary normalization from a fat/fructose/cholesterol-rich diet to chow caused stagnation of body weight and body fat percentage, normalized intravenous glucose tolerance index (K_G) and plasma lipid levels.

Conclusion

Dietary normalization led to lower LV collagen content in obese Göttingen Minipigs. Despite gross obesity and significant deteriorations in glucose and lipid metabolism, only mild myocardial changes were found in this model of obesity and therefore further model optimization is warranted in order to induce more severe myocardial changes before dietary or pharmacological interventions.

Exercise training reverses age-induced diastolic dysfunction and restores coronary microvascular function

KEY POINTS

In a rat model of ageing that is free of atherosclerosis or hypertension, E/A, a diagnostic measure of diastolic filling, decreases, and isovolumic relaxation time increases, indicating that both active and passive ventricular relaxation are impaired with advancing age. Resting coronary blood flow and coronary functional hyperaemia are reduced with age, and endothelium-dependent vasodilatation declines with age in coronary resistance arterioles. Exercise training reverses age-induced declines in diastolic and coronary microvascular function. Thus, microvascular dysfunction and inadequate coronary perfusion are likely mechanisms of diastolic dysfunction in aged rats. Exercise training, initiated at an advanced age, reverses age-related diastolic and microvascular dysfunction; these data suggest that late-life exercise training can be implemented to improve coronary perfusion and diastolic function in the elderly.

ABSTRACT

The risk for diastolic dysfunction increases with advancing age. Regular exercise training ameliorates age-related diastolic dysfunction; however, the underlying mechanisms have not been identified. We investigated whether (1) microvascular dysfunction contributes to the development of age-related diastolic dysfunction, and (2) initiation of late-life exercise training reverses age-related diastolic and microvascular dysfunction. Young and old rats underwent 10 weeks of exercise training or remained as sedentary, cage-controls. Isovolumic relaxation time (IVRT), early diastolic filling (E/A), myocardial performance index (MPI) and aortic stiffness (pulse wave velocity; PWV) were evaluated before and after exercise training or cage confinement. Coronary blood flow and vasodilatory responses of coronary arterioles were evaluated in all groups at the end of training. In aged sedentary rats, compared to young sedentary rats, a 42% increase in IVRT, a 64% decrease in E/A, and increased aortic stiffness (PWV: 6.36 ± 0.47 vs.4.89 ± 0.41, OSED vs. YSED, P < 0.05) was accompanied by impaired coronary blood flow at rest and during exercise. Endothelium-dependent vasodilatation was impaired in coronary arterioles from aged rats (maximal relaxation to bradykinin: 56.4 ± 5.1% vs. 75.3 ± 5.2%, OSED vs. YSED, P < 0.05). After exercise training, IVRT, a measure of active ventricular relaxation, did not differ between old and young rats. In old rats, exercise training reversed the reduction in E/A, reduced aortic stiffness, and eliminated impairment of coronary blood flow responses and endothelium-dependent vasodilatation. Thus, age-related diastolic and microvascular dysfunction are reversed by late-life exercise training. The restorative effect of exercise training on coronary microvascular function may result from improved endothelial function.

Fibulin-5 null mice with decreased arterial compliance maintain normal systolic left ventricular function, but not diastolic function during maturation

Abstract The large arteries serve as compliant vessels that store energy during systole and return it during diastole. This function is made possible by the elastic fibers in the arterial wall that are assembled during late embryonic and early postnatal development from various proteins, including fibulin-5. Mice and humans with insufficient amounts of fibulin-5 have reduced arterial compliance as adults. Reduced compliance of the large arteries is correlated with hypertension, reduced cardiac function, and an increased risk of death from cardiac and cardiovascular disease. The goal of this study was to quantify arterial compliance, blood pressure, and left ventricular (LV) function from early postnatal development to young adulthood in fibulin-5 null (Fbln5-/-) mice to determine the effects of reduced arterial compliance during this critical period of elastic fiber assembly. We find that ascending aorta compliance is reduced as early as postnatal day (P) 7 and carotid artery compliance is reduced by P21 in Fbln5-/- mice. We did not find significant increases in systolic blood pressure by P60, but pulse pressures are increased by P21 in Fbln5-/- mice. LV systolic function, as measured by ejection fraction and fractional shortening, is unaffected in Fbln5-/- mice. However, LV diastolic function, as measured by tissue Doppler imaging, is compromised at all ages in Fbln5-/- mice. We propose that Fbln5-/- mice represent a suitable model for further studies to determine mechanistic relationships between arterial compliance and LV diastolic function.

Early diastolic function during exertion influences exercise intolerance in patients with hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) patients with preserved left ventricular ejection fraction (LVEF) often develop dyspnea and exercise intolerance. Diastolic dysfunction may contribute to exercise intolerance in these patients. This study aimed to clarify our hypothesis as to whether diastolic function rather than systolic function would be associated with exercise intolerance in HCM using two-dimensional (2D) speckle tracking echocardiography during exercise.

METHODS

Thirty-three HCM patients (mean age 59.3 ± 15.7 years) underwent 2D speckle tracking echocardiography at rest and during submaximal semi-supine bicycle exercise. Global longitudinal strain (LS), LS rate during systole (LSRs), early diastole (LSRe), and late diastole (LSRa) were measured. The symptom-limited cardiopulmonary exercise testing was performed using a cycle ergometer for measuring the peak oxygen consumption (peak [Formula: see text]).

RESULTS

In the multivariate linear regression analysis, peak [Formula: see text] did not associate with strain or strain rate at rest. However, peak [Formula: see text] correlated with LS (β = -0.403, p = 0.007), LSRe (β = 6.041, p = 0.001), and LSRa (β = 5.117, p = 0.021) during exercise after adjustment for age, gender, and heart rate. The first quartile peak [Formula: see text] (14.2 mL/min/kg) was assessed to predict exercise intolerance. The C-statistic of delta LSRe was 0.74, which was relatively greater than that of delta LS (0.70) and delta LSRa (0.58), indicating that early diastolic function rather than systolic and late diastolic function affects exercise intolerance.

CONCLUSIONS

LSRe during exercise is closely associated with the peak [Formula: see text]. Early diastolic function during exercise is an important determinant of exercise capacity in patients with HCM.

Echocardiographic Characterization of Postnatal Development in Mice with Reduced Arterial Elasticity

PURPOSE

Decreased expression of elastin results in smaller, less compliant arteries and high blood pressure. In mice, these differences become more significant with postnatal development. It is known that arterial size and compliance directly affect cardiac function, but the temporal changes in cardiac function have not been investigated in elastin insufficient mice. The aim of this study is to correlate changes in arterial size and compliance with cardiac function in wildtype (WT) and elastin haploinsufficient (Eln^+/- ) mice from birth to adulthood.

METHODS

Ultrasound scans were performed at the ages of 3, 7, 14, 21, 30, 60, and 90 days on male and female WT and Eln^+/- mice. 2-D ultrasound and pulse wave Doppler images were used to measure the dimensions and function of the left ventricle (LV), ascending aorta and carotid arteries.

RESULTS

Eln^+/- arteries are smaller and less compliant at most ages, with significant differences from WT as early as 3 days old. Surprisingly, there are no correlations (R² < 0.2) between arterial size and compliance with measures of LV hypertrophy or systolic function. There are weak correlations (0.2 < R² < 0.5) between arterial size and compliance with measures of LV diastolic function.

CONCLUSIONS

Eln^+/- mice have similar cardiac function to WT throughout postnatal development, demonstrating the remarkable ability of the developing cardiovascular system to adapt to mechanical and hemodynamic changes. Correlations between arterial size and compliance with diastolic function show that these measures may be useful indicators of early diastolic dysfunction.

The onset of left ventricular diastolic dysfunction in SHR rats is not related to hypertrophy or hypertension

Left ventricular (LV) diastolic dysfunction, particularly relaxation abnormalities, are known to be associated with the development of LV hypertrophy (LVH). Preliminary human and animal studies suggested that early LV diastolic dysfunction may be revealed independently of LVH. However, whether LV diastolic dysfunction is compromised before the onset of hypertension and LVH remains unknown. We therefore evaluated LV diastolic function in spontaneously hypertensive rats (SHR) at different ages and tested whether LV diastolic dysfunction is associated with abnormal intracellular calcium homeostasis. LV systolic and diastolic functions were evaluated by invasive and echocardiographic methods in 3-week-old (without hypertension) and 5-week-old (with hypertension) SHR and Wistar-Kyoto control rats. Basal intracytoplasmic calcium and sarcoplasmic reticulum (SR) Ca2+ contents were measured in cardiomyocytes using fura-2 AM. Sarco(endo)plasmic Ca2+-ATPase isoform 2a (SERCA 2a) and phospholamban (PLB) expressions were quantified by Western blot and quantitative RT-PCR techniques. LV relaxation dysfunction was observed in 3-week-old SHR rats before onset of hypertension and LVH. An increase in basal intracytoplasmic Ca2+ and a decrease in SR Ca2+ release were demonstrated in SHR. Decreased expression of SERCA 2a and Ser16 PLB (p16-PLB) protein levels was also observed in SHR rats, whereas mRNA expression was not decreased. For the first time, we have shown that LV myocardial dysfunction precedes hypertension in 3-week-old SHR rats. This LV myocardial dysfunction was associated with high diastolic [Ca2+]i possibly due to decreased SERCA 2a and p16-PLB protein levels. Diastolic dysfunction may be a potential predictive marker of arterial hypertension in genetic hypertension syndromes.

Left ventricular strain and untwist in hypertrophic cardiomyopathy: relation to exercise capacity

Background

Nonobstructive hypertrophic cardiomyopathy (nHCM) is often associated with reduced exercise capacity despite hyperdynamic systolic function as measured by left ventricular ejection fraction. We sought to examine the importance of left ventricular strain, twist, and untwist as predictors of exercise capacity in nHCM patients.

Methods

Fifty-six nHCM patients (31 male and mean age of 52 years) and 43 age- and gender-matched controls were enrolled. We measured peak oxygen consumption (peak Vo₂) and acquired standard echocardiographic images in all participants. Two-dimensional speckle tracking was applied to measure rotation, twist, untwist rate, strain, and strain rate.

Results

The nHCM patients exhibited marked exercise limitation compared with controls (peak Vo₂ 23.28 ± 6.31 vs 37.70 ± 7.99 mL/[kg min], P < .0001). Left ventricular ejection fraction in nHCM patients and controls was similar (62.76% ± 9.05% vs 62.48% ± 5.82%, P = .86). Longitudinal, radial, and circumferential strain and strain rate were all significantly reduced in nHCM patients compared with controls. There was a significant delay in 25% of untwist in nHCM compared with controls. Both systolic and diastolic apical rotation rates were lower in nHCM patients. Longitudinal systolic and diastolic strain rate correlated significantly with peak Vo₂ (r = −0.34, P = .01 and r = 0.36, P = .006, respectively). Twenty-five percent untwist correlated significantly with peak Vo₂ (r = 0.36, P = .006).

Conclusions

In nHCM patients, there are widespread abnormalities of both systolic and diastolic function. Reduced strain and delayed untwist contribute significantly to exercise limitation in nHCM patients.

Effects of resistance training on ventricular function and hypertrophy in a rat model

OBJECTIVE

The purpose of this study was to follow the ventricular function and cardiac hypertrophy in rats undergoing a resistance-training program for a period of 3 months.

DESIGN

Forty animals were divided into two major groups: control (n=16) and resistance trained (n=24). From the resistance-trained group, 12 animals were resistance trained for 1 month and another 12 for 3 months. The resistance-training protocol was performed with 4 sets of 12 repetitions using 65% to 75% of one repetition maximum (maximum lifted weight with the exercise apparatus).

METHODS

Echocardiographic analysis was performed at the beginning of the resistance-training period and at the end of each month. The repetition maximum was measured every 2 weeks. Cardiac hypertrophy was determined by echocardiography, by the absolute weight of the cardiac chambers and by histology of the left ventricle.

RESULTS

Before resistance training, both groups had similar repetition maximums, ranging from 1.8-fold to 2-fold the body weight; however, at the end of the resistance-training period, the repetition maximum of the resistance-trained group was 6-fold greater than the body weight. The left ventricular mass as assessed by echocardiography was 8%, 12% and 16% larger in the resistance-trained group than in the control group in the first, second and third months, respectively. This hypertrophy showed a similar increase in the interventricular septum and in the free posterior wall mass. There was no reduction in the end-diastolic left ventricular internal diameter during the 3-month resistance-training period. Systolic function did not differ between the groups throughout the resistance-training period.

CONCLUSION

Resistance training induces the development of concentric cardiac hypertrophy without ventricular dysfunction or cavity reduction. Although diastolic function was not completely investigated, we cannot exclude the possibility that resistance training results in diastolic dysfunction.

Diastolic filling abnormalities in children with essential hypertension

OBJECTIVE

To evaluate whether essential hypertension impacts diastolic function in children.

STUDY DESIGN

In this cross-sectional study, patients with essential hypertension (n = 50) were compared with a normotensive group (n = 53). Echocardiographic assessment of diastolic function included measures derived from transmitral, color M-mode, and tissue Doppler interrogation. Cardiac dimensions, wall thickness, geometry, and systolic function were also assessed. Multiple linear regression analysis was performed to identify predictors of altered diastolic function.

RESULTS

Diastolic filling abnormalities were found in 36% of the children with blood pressure elevation. Those subjects with concentric hypertrophy were more significantly affected. Abnormalities in indices reflective of left ventricular (LV) relaxation occurred more commonly (39%) than those of LV compliance (33%). Elevated indexed LV mass was found to be the most significant independent predictor of diastolic filling abnormalities.

CONCLUSIONS

LV diastolic filling abnormalities were found in one-third of the pediatric subjects with essential hypertension. Whether these changes represent an adaptive or maladaptive response requires further study.

Left ventricular hypertrophy in Caucasian master athletes: Differences with hypertension and hypertrophic cardiomyopathy

AIM

To study, by conventional echocardiography, left ventricular remodelling and function in master athletes, hypertension and hypertrophic cardiomyopathy.

METHODS

We studied 30 master athletes (MA; soccer players; mean age 43.9+/-5.9), 24 subjects with essential hypertension (HYP; 46.6+/-6), 20 patients with hypertrophic cardiomyopathy (HCM; 42.2+/-9) and 30 normal individuals (CG; 43.4+/-5). An integrated M-mode/two-dimensional echocardiographic analysis was performed to determine chambers dimensions, relative wall thickness (RWT) and left ventricular mass (LVM), indexed to height in meters raised to the power of 2.7 (LVM/h(2.7)). Cut-off levels for LVM/h(2.7) and RWT were defined to assess 4 different patterns of LV geometric remodelling. In addition, we measured indexes of global systolic performance and indexes of global diastolic function.

RESULTS

LV wall thickness and LV end-diastolic dimensions were higher in MA than controls, but significantly lower than other groups. LVH/h(2.7) was increased in 79% of HYP and in 95% of HCM, but was within the normal limits in MA. LV geometry was normal in 22 out of 30 MA (73%), while the remaining (8 athletes, 27%) showed a concentric remodelling. Systolic function (FS and EF) was normal in MA, but was slightly reduced in HYP and increased in HCM. Analysis of diastolic function showed an abnormal relaxation pattern in all HYP and 95% of HCM, but was normal in all MA. The ratio between peak filling rate and stroke volume (PFR/SV), a relatively independent index of diastolic function, was significantly greater in hypertensive patients with normal LV remodelling compared to those without it (4+/-0.39 vs. 4.91+/-0.19; P = 0.0002).

CONCLUSION

MA showed lower values of wall thickness, LV dimensions and LV mass compared with HYP and HCM. Despite an abnormal remodelling, all the athletes showed a normal systolic and diastolic function. The differential diagnosis between MA, HYP and HCM is feasible by accurate, comprehensive standard Doppler echocardiography.

Diastolic ventricular dysfunction as a marker for hypertrophic cardiomyopathy in a family with a novel alpha-tropomyosin mutation

BACKGROUND

Early identification of familial cases of hypertrophic cardiomyopathy (HCM) depends on screening echocardiography, but hypertrophy may not be the most sensitive marker for the disease. We report the echocardiographic findings of a family with HCM and a newly reported mutation in the gene (TPM1) encoding alpha-tropomyosin.Methods and results An 8-year-old girl had sudden cardiac death, and was found to have HCM and a novel L185R-TPM1 mutation on postmortem examination. Screening echocardiograms and DNA analyses were performed on her family. Of the 5 remaining family members, 3 were genetically affected. Those without the TPM1 mutation had normal echocardiographic results. The only echocardiographic finding that identified all 3 of the gene-positive family members was an abnormal left ventricular diastolic filling pattern.

CONCLUSION

Abnormal left ventricular diastolic filling patterns, indicating diastolic dysfunction, may provide an early marker for the diagnosis of familial HCM in children, even in the absence of left ventricular hypertrophy.

MRI analysis of right ventricular function in normal and spontaneously hypertensive rats

Right ventricular structure and function were characterized in spontaneously hypertensive rats (SHR) using non-invasive magnetic resonance imaging (MRI) techniques. These studies therefore complement previous reports preoccupied with left ventricular changes associated with this condition. Eight SHR and eight control normotensive Wistar-Kyoto (WKY) rats were each subdivided into equal age-matched groups of 8 and 12 weeks. The right ventricle was imaged through a series of twelve contiguous 1.37-1.75 mm transverse sections at twelve equally spaced time-points that covered both systole and most of diastole thereby completely reconstructing right ventricular anatomy. This gave measurements of right ventricular myocardial mass that were consistent through all twelve time-points in all four experimental groups throughout their cardiac cycles. However, spontaneous hypertension increased this right ventricular myocardial mass, as well as the end-diastolic (EDV) and end-systolic volumes (ESV). Although stroke volume (SV) was conserved, decreases in ejection fraction (EF), a positive shift in the relationship between SV and EDV, and reduced indices of systolic ejection rates in SHR rats compared with the age-matched normal WKY controls indicated significant systolic dysfunction. Additionally, reductions in the rates of diastolic relaxation suggested the onset of diastolic dysfunction. Thus, the non-invasive nature of MRI has made it possible for the first time to demonstrate alterations in structure of the right ventricle and in quantitative indicators of its systolic and diastolic function in the SHR model of hypertension.

Four year follow up of aortic valve replacement for isolated aortic stenosis: a link between reduction in pressure overload, regression of left ventricular hypertrophy, and diastolic function

OBJECTIVE

To evaluate changes in left ventricular function and the impact of ventricular hypertrophy and pressure gradient early and late after aortic valve replacement in patients with isolated aortic stenosis.

DESIGN

41 patients with isolated aortic stenosis and normal systolic function underwent cross sectional and Doppler echocardiography two months before and two weeks and four years after aortic valve replacement.

RESULTS

Early after the operation, left ventricular mass index (mean (SD)) decreased from 187 (44) g/m(2) to 179 (46) g/m(2), because of a reduction in end diastolic diameter (p < 0.05). Aortic pressure gradients were reduced, as expected. Isovolumic relaxation time was reduced from 93 (20) ms to 78 (12) ms, and deceleration time from 241 (102) ms to 205 (77) ms (p < 0.05). At four years, left ventricular mass index was further reduced to 135 (30) g/m(2) (p < 0.01) as a result of wall thickness reduction in the interventricular septum (from 14 (1.6) mm to 12 (1.4) mm, p < 0.01) and the posterior wall (from 14 (1.6) mm to 12 (1.3) mm, p < 0.01). Diastolic function, expressed by a reduction in isovolumic relaxation time from 93 (20) ms to 81 (15) ms (p < 0.01) and deceleration time from 241 (102) ms to 226 (96) ms (p < 0.05), remained improved. Prolonged isovolumic relaxation time was associated with significant septal and posterior wall hypertrophy (wall thickness > 13 mm) (p < 0.05), whereas prolonged deceleration time was related to high residual gradient (peak gradient > 30 mm Hg ) (p < 0.01).

CONCLUSIONS

Left ventricular diastolic function improves early after surgery for aortic stenosis in parallel with the reduction in the aortic gradient. However, prolongation of Doppler indices of myocardial relaxation and ventricular filling is observed in patients with significant left ventricular hypertrophy and a residual pressure gradient early after surgery. At four years postoperatively, diastolic function remains improved.

Noninvasive indexes of left atrial diastolic function in hypertrophic cardiomyopathy

OBJECTIVES

Our goal was to noninvasively assess left atrial diastolic function and its relation to the impaired left ventricular filling in patients with hypertrophic cardiomyopathy.

METHODS AND RESULTS

We studied 34 patients with hypertrophic cardiomyopathy, 26 patients with secondary forms of left ventricular hypertrophy (aortic stenosis, fixed subaortic stenosis, hypertension), and 21 control subjects. Left atrial diastolic function was assessed by measuring acceleration time (SAT), deceleration time (SDT), and the EF (mean deceleration rate) slope of the pulmonary venous flow systolic wave (SW). Left ventricular diastolic function assessed by transmitral Doppler included peak early left ventricular and peak atrial filling velocities, the ratio of early-to-late peak velocities, isovolumic relaxation time, deceleration time, and EF slope. In patients with hypertrophic cardiomyopathy, acceleration time was significantly reduced (P<.05), deceleration time was significantly prolonged (P<.0001), and EF slope was significantly reduced (P<.01). These indexes were similar among the other two groups. No statistically significant difference existed between the subgroups of hypertrophic cardiomyopathy in the above indexes. Patients with hypertrophic cardiomyopathy and secondary forms of left ventricular hypertrophy had evidence of left ventricular diastolic dysfunction. In patients with hypertrophic cardiomyopathy, no correlation existed between left atrial and left ventricular diastolic function indexes (r = -0.26 to 0.33).

CONCLUSIONS

Echocardiographic indexes of left atrial relaxation and filling are abnormal in patients with hypertrophic cardiomyopathy but not in secondary forms of left ventricular hypertrophy. These indexes are abnormal in all forms of hypertrophic cardiomyopathy irrespective of left ventricular outflow tract obstruction and distribution of hypertrophy; they are not solely attributable to left ventricular diastolic dysfunction. The above may imply that hypertrophic cardiomyopathy is a cardiac myopathic disease that involves the heart muscle as a whole, irrespective of distribution of hypertrophy and obstruction.

Usefulness of early diastolic flow propagation velocity measured by color M-mode Doppler technique for the assessment of left ventricular diastolic function in patients with hypertrophic cardiomyopathy

Flow propagation velocity (FPV) of left ventricular (LV) filling flow has been shown to be a useful index for the evaluation of LV diastolic function, which is relatively independent of preload in myocardial infarction and dilated cardiomyopathy, but the usefulness of FPV for hypertrophic cardiomyopathy (HCM) has not yet been determined. In 23 HCM patients and 26 control subjects, peak transmitral flow velocities in early diastole (E) and during atrial contraction (A), E/A ratio, deceleration time of E velocity, and isovolumic relaxation time were measured with the conventional Doppler technique, and FPV was measured from color M-mode Doppler images of LV filling flow. The time constant of LV isovolumic pressure decay (tau) was measured by a micro-manometer-tipped catheter in all HCM patients and 13 control subjects. Flow propagation velocity was significantly lower and deceleration time was significantly greater in HCM patients than in the control subjects, though no significant differences were observed in the other noninvasive indexes. Tau was significantly prolonged in HCM patients compared with that of control subjects (54+/-12 cm/s and 32 +/-7 cm/s, respectively; P<.0001). While the conventional indexes did not correlate with tau among the 36 patients in whom invasive studies were performed, FPV correlated well with tau (r = -0.76, P<.0001). Flow propagation velocity is a useful noninvasive index for the assessment of LV diastolic function in patients with HCM.

Effect of endurance exercise training on left ventricular size and remodeling in older adults with hypertension

BACKGROUND

It is not known whether exercise training can induce a reduction of blood pressure (BP) and a regression of left ventricular hypertrophy (LVH) in older hypertensive subjects. This study was designed to determine whether endurance exercise training, by lowering BP, can induce regression of LVH and left ventricular (LV) concentric remodeling in older hypertensive adults.

METHODS

We studied 11 older adults with mild to moderate hypertension (BP 152.0 +/- 2.5/91.3 +/- 1.5 mm Hg, mean +/- SE), 65.5 +/- 1.2 years old, who exercised for 6.8 +/- 3.8 months. Seven sedentary hypertensive (BP 153 +/- 3/89 +/- 2 mm Hg) subjects, 68.5 +/- 1 years old, served as controls. LV size and geometry and function were assessed with the use of two-dimensional echocardiography.

RESULTS

Exercise training increased aerobic power by 16% (p < .001), and it decreased systolic (p < .05) and diastolic (p < .05) BP, LV wall thickness (from 12.8 +/- 0.4 mm to 11.3 +/- 0.3 mm; p < .05), and the wall thickness-to-radius (h/r) ratio (from 0.48 +/- 0.02 to 0.41 +/- 0.01; p < .05). There were no significant changes in the controls. The changes in LV mass index (deltaLVMI) were different between the two groups. LV mass index decreased in the exercise group (deltaLVMI - 14.3 +/- 3.3 g) but not in the controls (deltaLVMI 1.4 +/- 4.1 g; p = .009). A multiple stepwise regression analysis showed that among clinical and physiological variables including changes in resting systolic BP, aerobic power, body mass index, and systolic BP during submaximal and maximal exercise, only the reduction in resting systolic BP correlated significantly with a regression of concentric remodeling (delta h/r ratio r = .80; p = .003). The other variables did not add to the ability of the model to predict changes in the h/r ratio.

CONCLUSIONS

The data suggest that exercise training can reduce BP and induce partial regression of LVH and LV concentric remodeling in older adults with mild or moderate hypertension.

Echocardiographic Doppler evaluation of left ventricular diastolic filling in older, highly trained male endurance athletes

Previously published data have suggested that endurance training does not retard the normative aging impairment of early left ventricular diastolic filling (LVDF). Those studies, suggesting no effect of exercise training, have not examined highly trained endurance athletes or their LVDF responses after exercise. We therefore compared LVDF characteristics in a group of older highly trained endurance athletes (n = 12, mean age 69 years, range 65-75) and a group of sedentary control subjects (n = 12, mean age 69 years, range 65-73) with no cardiovascular disease. For all subjects, M-mode and Doppler echocardiographic data were obtained at rest. After baseline studies, subjects underwent graded, maximal cardiopulmonary treadmill exercise testing using a modified Balke protocol. Breath-by-breath respiratory gas analysis and peak exercise oxygen consumption (VO(2)max) measurements were obtained. Immediately after exercise and at 3-6 minutes into recovery, repeat Doppler echocardiographic data were obtained for determination of LVDF parameters. VO(2)max (44 +/-6.3 vs 27+/-4.2 ml/kg/min, P<0.001), oxygen consumption at anaerobic threshold (35+/-5.4 vs 24+/-3.8 ml/kg/min, P<0.001), exercise duration (24+/-3 vs 12+/-6 minutes, P<0.001), and left ventricular mass index (61+/-13 vs 51+/-7.8 kg/m(2), P<0.05) were greater in endurance athletes than in sedentary control subjects, whereas body mass index was lower (22+/-1.7 vs 26+/-3.4 kg/m(2), P<0.001). No differences in any of the LVDF characteristics were observed between the groups with the exception of a trend toward a lower atrial filling fraction at rest in the endurance athlete group versus the control subjects (P = 0.07). High-intensity endurance exercise training promotes exceptional peak exercise oxygen consumption and cardiovascular stamina but does not appear to alter normative aging effects on left ventricular diastolic function.

Diastolic heart failure: standard Doppler approach and beyond

Evidence of normal systolic left ventricular function has been reported in up to 30-40% of patients with clinical signs of congestive heart failure, suggesting that diastolic dysfunction is an important predictor of prognosis and mortality. Doppler echocardiography as a noninvasive diagnostic procedure is able to provide immediate and relevant information on functional and structural changes underlying the clinical syndrome of heart failure. Four distinct early filling/late diastole (E/A) ratio patterns (normal, delayed relaxation, pseudonormal, restrictive) can be discerned if viewed within the context of other available clinical information. These patterns evolve from one to another in a single individual, with changes in disease evolution, treatment, and loading condition. They represent a continuum from normal to severe diastolic dysfunction, showing progressively increasing left ventricular (LV) chamber stiffness and subsequently decreasing deceleration time. The combination of Doppler restrictive filling pattern and decreased deceleration time provides important information that helps to differentiate gradations of diastolic dysfunction and has been found to be a potent predictor of prognosis and mortality in various cardiac conditions. When clinical and transthoracic data alone are not sufficient in guiding therapy of congestive heart failure, transesophageal echocardiography can be used to assess most Doppler flows, especially pulmonary venous and left atrial (LA) appendage flows. The use of the multiplane transducer in multiple intermediate scan planes further improves the possibility of optimizing the Doppler incident angle and obtaining the best Doppler recordings of the left upper or right upper pulmonary venous flow. Whereas LV diastolic dysfunction is common in patients with congestive heart failure and appears to be an important predictor of prognosis, little information is available about right ventricular (RV) diastolic dysfunction. The role of RV function in congestive heart failure has probably been underestimated and it is possible that RV diastolic dysfunction assessment is equally important in the follow-up of heart failure patients. Recently, 2 novel echocardiographic technologies for the assessment of ventricular wall dynamics have been developed--color kinesis and tissue Doppler imaging. Both techniques have recently been shown to provide global as well as regional information on LV contraction and filling. Complementary use of both techniques may allow a more complete noninvasive assessment of global and regional systo-diastolic LV function.

Can trasmitral Doppler E-waves differentiate hypertensive hearts from normal?

Physiological models of transmitral flow predict E-wave contour alteration in response to variation of model parameters (stiffness, relaxation, mass) reflecting the physiology of hypertension. Accordingly, analysis of only the E-wave (rather than the E-to-A ratio) should be able to differentiate between hypertensive subjects and control subjects. Conventional versus model-based image processing methods have never been compared in their ability to differentiate E-waves of hypertensive subjects with respect to age-matched control subjects. Digitally acquired transmitral Doppler flow images were analyzed by an automated model-based image processing method. Model-derived indexes were compared with conventional E-wave indexes in 22 subjects: 11 with hypertension and echocardiographically verified ventricular hypertrophy and 11 age-matched nonhypertensive control subjects. Conventional E-wave indexes included peak E, E, and acceleration and deceleration times. Model-based image processing-derived indexes included acceleration and deceleration times, potential energy index, and damping and kinematic constants. Intergroup comparison yielded lower probability values for model-based compared with conventional indexes. In the subjects studied, Doppler E-wave images analyzed by this automated method (which eliminates the need for hand-digitizing contours or the manual placement of cursors) demonstrate diastolic function alteration secondary to hypertension made discernible by model-based indexes. The method uses the entire E-wave contour, quantitatively differentiates between hypertensive subjects and control subjects, and has potential for automated noninvasive diastolic function evaluation in large patient populations, such as hypertension and other transmitral flow velocity-altering pathophysiological states.

Influence of the angiotensin converting enzyme I/D gene polymorphisms on left ventricular diastolic filling in patients with essential hypertension

BACKGROUND

An insertion/deletion (I/D) polymorphism in the angiotensin converting enzyme (ACE) gene accounts for 50% of the variance in serum ACE activity. ACE is responsible for the generation of angiotensin II, which not only has pressor and mitogenic activities but also exerts effects on left ventricular diastolic performance.

OBJECTIVE

To investigate the contribution of genetic polymorphisms at the ACE gene to the development of diastolic functional abnormalities in 100 patients with essential hypertension.

METHODS AND RESULTS

The left ventricular mass (LVMI) of each patient was assessed echocardiographically. We calculated peak and integral early:late left ventricular diastolic filling ratios (E:AP, and E:AI, respectively) and determined the ACE genotype from leukocyte DNA. There was no significant difference in age, sex, blood pressure and LVMI among genotype groups. Analysis of covariance modelled for indices of diastolic function, adjusted for age, sex, heart rate and LVMI, demonstrated that the E:AP interacted with age (P < 0.0001), heart rate (P < 0.001) and ACE genotype (P = 0.018). Similarly, the E:AI interacted with age (P < 0.001), heart rate (P = 0.025) and ACE genotype (P = 0.047). There was a strong correlation between the E:AP and the LVMI for the DD group (r = -0.81, P < 0.0001) but not for the ID (r = -0.03, P = 0.83) and II (r = -0.23, P = 0.23) groups.

CONCLUSIONS

These findings suggest that that the I/D polymorphism of the ACE gene influences the relationship between left ventricular mass and echocardiographic left ventricular diastolic filling abnormalities in patients with essential hypertension.

Doppler diastolic filling indexes in relation to disease states

This study compares mean Doppler-derived diastolic filling indexes in a variety of disease states in a large, population-based sample. Pulse-wave Doppler was used to examine 880 eligible participants of the Framingham Heart Study. Peak velocity of early flow and late flow, ratio of early to late peak velocities, atrial filling fraction, and early filling wave acceleration and deceleration times were obtained. Multiple linear regression analyses were performed comparing mean values for individuals with hypertension, diabetes, coronary disease, cardiovascular disease, and pulmonary disease. Hypertension was associated with a greater peak velocity late flow (0.027 m/sec; 95% confidence interval, 0.006, 0.047; p = 0.011), and diabetes was associated with a larger mean deceleration time (0.12 sec, confidence interval, 0.002, 0.021; p = 0.016). In multivariate analyses, hypertension continued to show a strong association with altered Doppler diastolic filling patterns, p value 0.009, whereas in diabetes, the multivariate p value was 0.28.

Influence of basal nitric oxide secretion on cardiac function in man

1. Nitric oxide is recognised as an important biological mediator, which is thought to be involved in cardiovascular homeostasis. The purpose of this study was to investigate the effects of basal nitric oxide synthesis on cardiac function in man, by blocking nitric oxide synthesis with NG-monomethyl-L-arginine (L-NMMA). 2. Eight normal volunteers were studied on two separate occasions. Measurements of heart rate, blood pressure and echocardiographic indices of left ventricular systolic and diastolic function were made at baseline on each day and every 20 min during incremental infusion of L-NMMA (0.1, 0.2, 0.5, 1.0 and 2.0 mg kg-1 h-1) or placebo. 3. A trend towards reduction in heart rate was observed with L-NMMA infusion although this did not reach statistical significance, whereas significant increases in both systolic blood pressure (at 2.0 mg kg-1 h-1) and systemic vascular resistance index (at 0.5 mg kg-1 h-1) were seen. 4. L-NMMA infusion caused significant reductions in stroke distance and cardiac index, although there was no change in the ratio of end systolic wall stress/end systolic volume index (an afterload independent index of left ventricular systolic performance). 5. The isovolumic relaxation time significantly increased with L-NMMA infusion, together with a significant reduction in the 'E' wave flow velocity integral. Reductions in both peak E/A ratio and E/A flow velocity integral ratio were also seen, although these failed to reach statistical significance. 6. In conclusion, the basal generation of nitric oxide in man appears to maintain a vasodilated state, and modifies left ventricular diastolic filling parameters.

Left ventricular diastolic function in hypertension: a 4 year follow-up study

In order to assess the long term effects of antihypertensive treatment on left ventricular diastolic function, 26 hypertensive patients were followed up for a mean of 4.25 years with two-dimensional and Doppler echocardiography. A significant reduction in left ventricular mass index was first apparent after 9 months of therapy (mean (S.D.) 124 (22) vs. 114 (18) g/m2, P < 0.01), and this was maintained over the 4.25 year period (124 (22) vs. 117 (17) g/m2, p < 0.05). At 9 months there was no change in either isovolumic relaxation time (108 (26) vs. 108 (17) ms, P = N.S.) or left ventricular filling as assessed by peak flow velocity E/A ratio (0.94 (0.22) vs. 0.95 (0.27), P = N.S.). However, after 4.25 years there was a significant improvement in IVRT (108 (26) vs. 83 (11) ms, P < 0.01) with a trend towards an improved peak flow velocity E/A ratio, although this did not reach statistical significance (0.95 (0.27) vs. 1.02 (0.26), P = N.S.). Of the 14 patients who had an abnormal isovolumic relaxation time at baseline, 12 normalised and 2 improved. These findings suggest that left ventricular diastolic dysfunction in hypertension may be reversed by prolonged antihypertensive treatment.

Effects of type 1 diabetes mellitus on cardiac function: a study of monozygotic twins

OBJECTIVE

To investigate left ventricular size and function in type 1 diabetes and their relation with diabetes duration, glycaemic control, autonomic dysfunction, and complications of diabetes.

DESIGN

Cross sectional study using a pulsed wave Doppler echocardiogram to assess left ventricular dimensions, wall thickness, and transmitral blood flow velocity signals.

PATIENTS

40 monozygotic twin pairs (23 male, mean age 26 years) discordant for type 1 diabetes and 40 non-diabetic singleton controls with no clinical evidence of cardiac ischaemia.

RESULTS

For all Doppler echocardiographic measurements there were strong correlations between monozygotic twins but not between twins and control subjects. Left ventricular dimensions, wall thickness and systolic function, peak E velocity, and the velocity integrals of early left ventricular filling were similar in all three groups. Peak A velocity and the velocity integrals of late ventricular filling (mean (SD)) were greater in diabetic twins (45 (12) v 38 (8) cm/s, P = 0.002; and 32 (11) v 26 (6), P = 0.0002). Diabetic twins had lower E/A ratio (1.59 (0.39) v 1.83 (0.39), P < 0.001), greater atrial filling fraction to total diastolic filling (28 (6) v 25 (5)%, P = 0.002), and prolonged isovolumic relaxation time (72 (12) v 63 (9) ms, P < 0.001). The differences in Doppler findings between diabetic and non-diabetic twins were related to disease duration whereas the prolongation of the isovolumic relaxation time was related to cardiac autonomic dysfunction.

CONCLUSIONS

These results show that twins with type 1 diabetes have left ventricular diastolic dysfunction related to diabetes duration and cardiac autonomic dysfunction but not to glycaemic control or microvascular complications. In addition, genetic factors contribute to left ventricular dimension and function.

Filling patterns in left ventricular hypertrophy: a combined acoustic quantification and Doppler study

OBJECTIVES

The purpose of this study was to evaluate the potential of acoustic quantification compared with Doppler echocardiography for assessment of left ventricular diastolic dysfunction.

BACKGROUND

Diastolic dysfunction usually accompanies left ventricular hypertrophy. Although Doppler echocardiography is widely used, it has known limitations in the diagnosis of diastolic abnormalities. The ventricular area-change waveform obtained with acoustic quantification technology may provide an alternative to assess diastolic dysfunction.

METHODS

Potential acoustic quantification variables (peak rate of area change and mean slope of area change rate during rapid filling, amount of relative area change during rapid filling and atrial contraction) were obtained and compared with widely used Doppler indexes of ventricular filling (isovolumetric relaxation time, pressure half-time, peak early diastolic velocity/peak late diastolic velocity ratio, rapid filling, atrial contribution to filling) in 16 healthy volunteers and 30 patients with left ventricular hypertrophy.

RESULTS

Criteria for abnormal relaxation were present in 68% of patients by acoustic quantification and in 64% of patients by Doppler echocardiography. However, abnormal relaxation was identified in 80% of patients by one or both methods. Acoustic quantification indicated abnormal relaxation in the presence of completely normalized Doppler patterns and in patients with mitral regurgitation or abnormal rhythm with unreliable Doppler patterns.

CONCLUSIONS

Acoustic quantification potentially presents a new way to assess diastolic dysfunction. This technique may be regarded as complementary to Doppler echocardiography. The combined use of the methods may improve the diagnosis of left ventricular relaxation abnormalities.

Evaluation of left atrial contribution to left ventricular filling in aortic stenosis by velocity-encoded cine MRI

Velocity-encoded cine MRI (VEC-MRI) can measure volume flow at specified site in the heart. This study used VEC-MRI to measure flow across the mitral valve to compare the contribution of atrial systole to left atrial filling in normal subjects and patients with left ventricular hypertrophy. The study population consisted of 12 normal subjects (mean age 34.5 years) and nine patients with various degrees of left ventricular hypertrophy resulting from aortic stenosis (mean age 70 years). VEC-MRI was performed in double-oblique planes through the heart to measure both the mitral inflow velocity pattern (E/A ratio) and the volumetric flow across the mitral valve. The left atrial contribution to left ventricular filling (AC%) was calculated. The results were compared with Doppler echocardiographic parameters. The VEC-MRI-derived mitral E/A ratios showed a significant linear correlation with E/A ratios calculated from Doppler echocardiography (r = 0.94), and the VEC-MRI-derived E/A ratios (2.1 +/- 0.5 vs 1.0 +/- 0.4) and AC% values (24.9 +/- 7.2 vs 45.7 +/- 16.4) were significantly different between normal subjects and patients with aortic stenosis (p < 0.01 in both groups). The same differences were seen in the Doppler echocardiographic parameters. The VEC-MRI-derived E/A ratio and AC% showed significant hyperbolic and linear correlations with left ventricular mass indexes (r = 0.95 and 0.86). In addition, the VEC-MRI-determined E/A ratio and the volumetric AC% displayed a highly significant hyperbolic correlation (r = 0.95). Thus VEC-MRI can be used to evaluate left ventricular diastolic filling characteristics in normal subjects and patients with abnormalities of diastolic filling.

Isovolumetric relaxation flow in patients with ischemic heart disease

OBJECTIVES

The purpose of this study was to clarify the characteristics of flow during the isovolumetric relaxation period and to analyze the relation between these flow patterns and standard hemodynamic indexes.

BACKGROUND

Outward motion of the left ventricle during the isovolumetric relaxation period has been observed by cineangiography. However, there is little information about blood flow during this period.

METHODS

Seventy-nine patients with ischemic heart disease were examined by pulsed Doppler echocardiography and cardiac catheterization. All patients were classified into three groups according to the observed patterns of isovolumetric relaxation flow: group I (n = 41), flow directed toward the apex; group II (n = 21), flow directed toward the base, and group III (n = 17), low velocity flow (< 12 cm/s) without a dominant direction. Patients in group I were further classified into group Ia (n = 19) with normal ventriculograms and group Ib (n = 22) with asynergy.

RESULTS

Left ventricular ejection fraction and negative first derivative of left ventricular pressure were significantly lower in group II (49 +/- 9% and 1,274 +/- 212 mm Hg/s, respectively) and group III (38 +/- 8% and 1,147 +/- 280 mm Hg/s, respectively) than in group Ia (68 +/- 7% and 1,727 +/- 358 mm Hg/s), each p < 0.01. Time constant was significantly prolonged in group II (49 +/- 6 ms) and group III (48 +/- 6 ms) compared with that in group Ia (41 +/- 6 ms), p < 0.05. On left ventriculography, patterns of outward wall motion during the isovolumetric relaxation period were associated with the patterns of isovolumetric relaxation flow.

CONCLUSIONS

Changes in left ventricular relaxation are accompanied by alterations in isovolumetric relaxation flow. It is therefore useful to evaluate isovolumetric relaxation flow when investigating early diastolic ventricular function.

Reduction of left ventricular hypertrophy: how beneficial?

Left ventricular hypertrophy (LVH) can no longer be considered a compensatory adaptation of the heart serving to normalize the increased wall stress in hypertension. Recent studies have indicated that LVH is a powerful pressure-independent risk factor for cardiovascular morbidity and mortality. The pathophysiologic sequelae of LVH are reduced ventricular filling and contractility, ventricular dysrhythmias, and diminished coronary reserve or myocardial ischemia. Left ventricular hypertrophy can be reduced by antihypertensive therapy, although not all drugs are equipotent in this regard. Recent studies have shown that such a reduction also improves the pathophysiologic sequelae of LVH, that is, ventricular filling, coronary reserve, and ventricular dysrhythmias, and maintains left ventricular pump function. Although the reversal of these pathophysiologic findings is encouraging, it remains unknown whether a reduction of LVH will ultimately reduce the excessive risk of sudden death, acute myocardial infarction, and congestive heart failure that has been associated with this disorder independent of arterial pressure.

Left ventricular hypertrophy: should it be reduced?

Left ventricular hypertrophy (LVH) is a structural adaptation of the heart to sustained hypertension, serving to normalize increased wall stress. Recent clinical studies have indicated that LVH is a powerful pressure-independent risk factor for cardiovascular morbidity and mortality, particularly sudden death, acute myocardial infarction, and congestive failure. The pathophysiologic sequelae of LVH consist of reduced ventricular filling and contractility, ventricular dysrhythmias, and diminished coronary reserve or myocardial ischemia. LVH can be reduced by antihypertensive therapy, although not all drugs are equipotent in this regard. Angiotensin-converting enzyme (ACE) inhibition seems to be the most powerful monotherapeutic modality for reducing LVH. Recent studies have shown that such a reduction also improves the pathophysiologic sequelae of LVH and maintains left ventricular pump function. Although the reversal of these pathophysiologic events is encouraging, it remains unknown whether reducing LVH will ultimately decrease the excessive risk of sudden death, acute myocardial infarction, and congestive heart failure that has been associated with this disorder independently of arterial pressure.

Effects of venous return reduction in hypertensive patients: is there a Doppler diastolic dysfunction index independent of preload reduction?

The aim of this study was to evaluate the effects of preload reduction on the Doppler transmitral flow pattern in the presence of diastolic dysfunction (hypertensive patients) and normal diastolic function (normal subjects) to identify, if present, one or more indexes of abnormal diastolic ventricular filling independent of variations in preload. For this purpose Doppler echocardiography was performed in 17 patients with hypertension and in 18 normal subjects under basal conditions and after 5 minutes of blood pressure cuff inflation at the root of the four limbs. The two groups showed a similar response to preload reduction: a significant reduction in peak velocity and the time-velocity integral of the E wave and in the ratio of peak velocities of E and A waves. Therefore the differences in left ventricular filling patterns between hypertensive and normal subjects observed under basal conditions were still present after preload reduction. The comparison between normal subjects after preload reduction and hypertensive patients in the basal state showed a higher peak velocity and time-velocity integral of the A wave in the latter (61.2 +/- 16.2 vs 46.2 +/- 9 cm/sec [p less than 0.002] and 5.4 +/- 1.8 vs 3.7 +/- 1 cm [p less than 0.002], respectively) with no differences in the ratios of peak velocities and time-velocity integrals of the E and A waves.(ABSTRACT TRUNCATED AT 250 WORDS)

Does a reduction in left ventricular hypertrophy reduce cardiovascular morbidity and mortality?

Left ventricular hypertrophy is an important risk factor for sudden death and other cardiovascular morbidity and mortality irrespective of the level of arterial blood pressure. Left ventricular hypertrophy, i.e. an increase in wall thickness at the expense of left ventricular volume, is an adaptive mechanism observed in patients with long standing arterial hypertension. Severe left ventricular hypertrophy is associated with a reduction in left ventricular compliance, impaired coronary reserve, ventricular ectopy, and impaired contractile function. Left ventricular hypertrophy can be reduced by antihypertensive therapy; however, not all antihypertensive agents have the same effect on left ventricular hypertrophy despite their similar effects on arterial blood pressure. Angiotensin converting enzyme (ACE) inhibitors appear to be the most powerful agents for reducing left ventricular hypertrophy, followed by the nondihydropyridine calcium antagonists. In addition to reducing left ventricular mass and arterial blood pressure, certain calcium antagonists also improve left ventricular filling, suppress ventricular ectopy, and maintain or enhance contractile function. However, despite these beneficial effects, it is not known whether the risk of cardiovascular morbidity and mortality can be prevented or reduced by specific antihypertensive agents.

Factors influencing Doppler indexes of left ventricular filling in healthy persons

Ninety-three healthy persons aged 11 to 91 years were studied to assess the factors influencing Doppler indexes of left ventricular (LV) diastolic filling. The effects of physical activity, alcohol consumption and smoking were tested in addition to those of age, sex, heart rate, body mass index, blood pressure, left atrial diameter, and LV end-diastolic diameter, wall thickness, mass and fractional shortening. The data were fitted stepwise into multiple linear regression models both in the total population and in 3 groups aged less than 40, 40 to 60 and greater than 60 years. In the total population, age explained 45 to 68% of the variation in the peak early and late diastolic velocities, their ratio, deceleration of the early velocity, atrial filling fraction and peak filling rate normalized to mitral stroke volume. With advancing age--and with increases in either body mass index, heart rate, diastolic blood pressure or LV mass--the indexes of early filling decreased, whereas with regular modest use of alcohol or regular aerobic exercise they increased (p less than 0.05 for all). In the middle-aged subjects, gender explained 32 to 57% of the variation in the peak atrial velocity, early to atrial peak velocity ratio and atrial filling fraction; the peak velocity ratio measured 1.4 +/- 0.3 (mean +/- standard deviation) in men vs 1.0 +/- 0.2 in women (p less than 0.001). In conclusion, many constitutional and physiologic factors and even life-style can influence the Doppler indexes of LV filling. This demonstrates the exquisite sensitivity of the method but indicates also that individual measurements must be interpreted with caution.

Left ventricular hypertrophy, compliance and ventricular filling

A total of 20 untreated hypertensive patients were divided into two equal groups matched for sex, age and blood pressure but with [mean diastolic wall thickness (MDWT) greater than 1.2 cm] or without (MDWT greater than 1.2 cm) left ventricular hypertrophy (LVH). All patients underwent pulsed doppler echocardiography and 99Tc radionuclide ventriculography at rest to assess diastolic and systolic abnormalities. In hypertensives with LVH the interventricular wall thickness, posterior wall thickness and relative diastolic wall thickness were significantly (P less than 0.01) higher and peak filling rate was significantly (P less than 0.01) lower than in hypertensives without LVH. The indices of systolic function, however, were not significantly different in the two patient groups. In hypertensives without LVH peak filling rate directly correlated with heart rate, whereas in those with LVH peak filling rate directly correlated with heart rate and the ratio of peak velocity of early left ventricular filling : peak velocity of late left ventricular filling due to atrial contraction. It is concluded that diastolic parameters may be useful tools for assessing myocardial compliance and may be effective markers of diastolic dysfunction.

Evaluation of left ventricular filling in dilated cardiomyopathy using digitized M-mode echocardiograms

Digital M-mode echocardiography describes a characteristic alteration in the pattern of left ventricular filling when a dilated cardiomyopathy is present. The peak rates of early diastolic dimension change (dD/dt and dD/dt/D) are uniformly reduced but remain unchanged in time of occurrence (time to dD/dt). The rapid filling period is slightly shortened compared to normals, but the %deltaD taking place during rapid filling is not different than normals. This pattern is distinct from characteristic alterations seen in other cardiac diseases that have preserved systolic performance. While M-mode indices of left ventricular filling may be altered by several factors, the most significant factors in dilated cardiomyopathy are the severity of systolic dysfunction and preload. Left-sided conduction delays and associated right ventricular enlargement have no demonstrable effect on very early portions of diastole, but the conduction delay does prolong the rapid filling period and reduce the extent of filling during this period. Combined use of digitized M-mode echocardiograms and Doppler analysis of transmitral flow may allow a more complete description of left ventricular filling in future studies.

Non-invasive assessment of left ventricular diastolic function in patients with systemic sclerosis

To evaluate the extent of left ventricular (LV) diastolic impairment in systemic sclerosis, we examined 30 consecutive patients (15 men and 15 women) with this condition, and compared the findings with the data for 48 age- and sex-matched randomly sampled controls. All patients were investigated by phonocardiography, pulse curve recording, and M-mode echocardiography. Twenty-three of 30 (77%) patients had LV hypertrophy and/or diastolic impairment. Interventricular septum (P = 0.0001), LV posterior wall (P less than 0.05), and the wall thickness to cavity dimension ratio (P less than 0.001) were increased in patients compared to controls, as was LV mass index (P less than 0.002). Five patients had asymmetric septal hypertrophy. LV end-diastolic dimension did not differ between groups. LV distensibility was impaired, as judged from apexcardiographic a/H ratio (P less than 0.05) and from an increased left atrial index (P less than 0.005). LV early filling was impaired, with a reduced left atrial emptying index (P = 0.0001), and a reduced rate of dimension increase in digitized M-mode (P less than 0.02). We found no evidence of impaired LV relaxation. Blood pressure did not differ between patients and controls. With longer duration of the disease, left atrial dimension appeared to increase (r = 0.42, P less than 0.05), while other variables were not related to disease duration. The impaired LV filling was not secondary to systolic dysfunction. We conclude that systemic sclerosis patients have an increased LV wall thickness, with impaired early filling properties and LV distensibility.

Effects of indapamide on left ventricular mass and function in systemic hypertension with left ventricular hypertrophy

Left ventricular hypertrophy (LVH) is frequently associated with hypertension and constitutes a major cardiovascular risk factor, the reduction of which should be considered when initiating antihypertensive therapy. To assess the effects of indapamide on LVH, 18 hypertensive patients were included in the study (11 men and 7 women, age 53.6 +/- 2.9 years, mean +/- standard deviation) whose supine diastolic blood pressure was greater than 95 mm Hg without (n = 11) or with (n = 7:6 beta blockers, 1 calcium antagonist) antihypertensive therapy. All presented with LVH, echocardiographically defined by a left ventricular mass index greater than 110 g/m2. After a 2-week preinclusion period, all patients received indapamide, 2.5 mg/day, for a period of 6 months. Physical examination including blood pressure measurement was performed on selection (M-1/2), before (M0), and after 1 (M1), 3 (M3) and 6 (M6) months of indapamide treatment, and echocardiography was performed at M0 and M6. Quality of life was evaluated by means of questionnaires completed by the patient and the physician, and a visual analog scale was completed by the patient at M-1/2, M0 and M6. All clinical parameters remained stable during the 2-week preinclusion period. Indapamide administration induced a highly significant reduction in both supine systolic and diastolic blood pressures from 173.9 +/- 2.9/100.5 +/- 1.2 mm Hg at M0 to 150.9 +/- 1.9/90.5 +/- 1.3 mm Hg at M1 (p less than 0.001), and 145.0 +/- 1.7/86.0 +/- 1.5 mm Hg at M6 (p less than 0.001). Similar favorable effects were observed in the upright position.(ABSTRACT TRUNCATED AT 250 WORDS)

Relation of filling pattern to diastolic function in severe left ventricular disease

M mode and Doppler echocardiograms, apex cardiograms, and phonocardiograms were recorded in 50 patients with severe ventricular disease of varying aetiology to examine how left ventricular filling is disturbed by cavity dilatation. The size of the left ventricular cavity was increased in all with a mean (SD) transverse diameter of 7.2 (0.8) cm at end diastole and 6.3 (0.8) cm at end systole. All were in sinus rhythm and 35 had functional mitral regurgitation. In nine patients, in whom filling period was less than 170 ms, transmitral flow showed only a single peak, representing summation. In the remainder there was a strikingly bimodal distribution of filling pattern. In 12 the ventricle filled dominantly with atrial systole (A fillers). Isovolumic relaxation was long (75 (35) ms) and wall motion incoordinate; mitral regurgitation was present in only one. In most (29) the left ventricle filled predominantly during early diastole (E fillers). Mitral regurgitation, which was present in 26, was much more common than in the A fillers, while the isovolumic relaxation time (10 (24) ms) was much shorter and the normal phase relations between flow velocity and wall motion were lost. In 24 E fillers no atrial flow was detected. In four there was no evidence of any mechanical activity, suggesting "atrial failure". In 20, either the apex cardiogram or the mitral echogram showed an A wave, implying that atrial contraction had occurred but had failed to cause transmitral flow, showing that ventricular filling was fundamentally disturbed in late diastole. A series of discrete abnormalities of filling, beyond those shown by Doppler alone, could thus be detected in this apparently homogeneous patient group by a combination of non-invasive methods. The presence and nature of these abnormalities may shed light on underlying physiological disturbances.

Current perspectives in hypertrophic cardiomyopathy: diagnosis, clinical management, and prevention of disability and sudden cardiac death

Hypertrophic cardiomyopathy is a rare primary myocardial disease known for its dramatic morphologic and clinical manifestations. Sudden cardiac death and functional cardiac symptoms are common. However, differing pathologic mechanisms may be responsible for similar clinical symptoms and make a unified approach to therapy impossible. This review will discuss the genetics, criteria for diagnosis, relationship among pathophysiologic abnormalities and clinical symptoms, and management of hypertrophic cardiomyopathy.

Intraventricular septal hypertrophy in type 1 diabetic patients with microalbuminuria or early proteinuria

To investigate whether the slightly increased blood pressure that occurs in early diabetic renal disease is associated with hypertensive left ventricular hypertrophy, M-mode echocardiograms were recorded in 11 non-diabetic control subjects and four groups of Type 1 diabetic patients. These were 15 patients without microvascular complications, 10 with microalbuminuria, 12 with early persistent proteinuria, and 8 with established renal impairment. Mean blood pressure was 133/80 mmHg (uncomplicated patients), 143/85 mmHg (microalbuminuria), 147/92 mmHg (early proteinuria) and 158/85 mmHg (renal impairment). Mean intraventricular septal width in the uncomplicated diabetic patients was 9.8 (SE 1.2) mm which did not differ from non-diabetic control subjects. Mean septal width was significantly greater in the other groups (microalbuminuria, 12.7 (1.1) mm, p less than 0.02; proteinuria, 12.0 (0.7) mm, p less than 0.05; renal impairment, 15.5 (1.8) mm, p less than 0.001). Left ventricular mass increased progressively between groups and was significantly increased in those with renal impairment (140 (21) vs 103 (5) g m-2 in uncomplicated patients, p less than 0.05). Septal width in the diabetic population not receiving antihypertensives (n = 37) was significantly correlated with systolic blood pressure (r = 0.45, p less than 0.005) which was the only variable independently related to septal width and ventricular mass. It appears that the slight increase in blood pressure that occurs in microalbuminuria and early proteinuria is frequently associated with hypertensive left ventricular hypertrophy.