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Regional diastolic dysfunction in postischaemic myocardium in calf: effect of nisoldipine.

OBJECTIVE: The aim was to assess the effect of nisoldipine on left ventricular systolic and diastolic function during prolonged myocardial ischaemia. METHODS: The left circumflex coronary artery was ligated for 2 h and reperfused for 4 h in 12 calves. The animals were randomised to a control group (n = 6) or to treatment with 1.25 mg.h-1 intravenous nisoldipine (n = 6) during 2 h of ischaemia. Circulatory support by a ventricular assist device was performed throughout the experiment except for the time of haemodynamic measurements. Regional wall thickening of a normal and an ischaemic left ventricular region was determined using pairs of ultrasonic crystals. Left ventricular pressure was measured by micromanometry. Left ventricular wall thickness and regional wall stiffness at a common preload of 10 mm Hg were calculated using an elastic model with shifting asymptote. RESULTS: Ten animals survived after 6 h. No difference was observed in systolic function between controls and nisoldipine treated animals. Systolic thickening of the ischaemic wall remained depressed 4 h after reperfusion and showed some recovery after dopamine infusion. Ischaemic wall stiffness at a common preload was lower after nisoldipine during ischaemia and reperfusion than in controls. Control wall stiffness remained unchanged during the whole experiment with and without nisoldipine. Diastolic thinning of the ischaemic wall was prevented by nisoldipine during ischaemia and after reperfusion. CONCLUSIONS: Prolonged myocardial ischaemia is associated with increased myocardial stiffness of the ischaemic wall. Mechanical unloading can help to bridge the acute phase but cannot prevent postischaemic diastolic dysfunction of the ischaemic wall. Nisoldipine has a beneficial effect on regional diastolic function during ischaemia and reperfusion by decreasing regional wall stiffness and preventing diastolic thinning of the ischaemic wall.

Animals↗

Left ventricular diastolic dysfunction in obese women.

AIM: To determine the direct effect of obesity on echocardiographic indices of diastolic left ventricular function METHODS: 44 obese (BMI > or =25 kg/m2) and 45 normal weight women were studied. They had no other pathological conditions. Echocardiographic indices of diastolic function were obtained, and dysfunction was assumed when at least two values differed by > or =2 SD from the normal weight group. RESULTS: In obese subjects, the values of maximum velocity of active mitral filling (A) were increased and pulmonary diastolic velocity was decreased significantly (p< 0,01); all other diastolic variables were unchanged. Subclinical diastolic dysfunction tend to be more prevalent among obese subjects but it was not significantly different from non obese (p= 0.11), being present in nine obese (20.5%) and 4 normal (8.9%) subjects. CONCLUSION: Subclinical left ventricular diastolic dysfunction is present in obese women.

Adult↗

Detection of diastolic dysfunction: acoustic quantification (AQ) in comparison to Doppler echocardiography.

OBJECTIVES: To evaluate the potential of acoustic quantification (AQ) in detection of diastolic dysfunction in comparison to Doppler analysis, we investigated, as a model of restrictive filling pattern, nonrejecting heart transplant recipients early postoperatively. BACKGROUND: AQ, an ultrasonic backscatter imaging system, enables instantaneous calculation of cavity areas and thus provides a new approach to diastolic function. METHODS: Of 27 pts who have undergone heart transplantation, echocardiography has been performed at the day of biopsy. During a time course of 8 weeks echocardiographic data have been analysed at 3 different time points (early, mid and late) in 16 nonrejecting pts. Indexes of the area-change waveform and its 1. derivative (dA/dt) obtained by AQ were opposed to usual Doppler indexes. RESULTS: In comparing data of the early and late time point of investigation, significant changes of early diastolic filling were detectable by AQ as well as by Doppler: End-diastolic areas have increased (p < 0.001), while peak filling rate (p < 0.0001), slope of area change during rapid filling (p < 0.001) and amount of relative area change during rapid filling (p < 0.001) have decreased. Complementary, Doppler derived pressure half-time (p < 0.0001) and isovolumic relaxation time (p < 0.0001) have increased while the peak early filling velocity (p < 0.0001) and its time velocity integral (p < 0.001) have decreased. CONCLUSION: An initial restrictive filling pattern has improved 8 weeks postoperatively. Since multiple indexes, obtained from the area change waveforms, in particular the for end-diastolic area normalized peak filling rate, seem to be highly sensitive in detecting changes of diastolic function, AQ may play an important complementary role in non-invasive evaluation of restrictive filling pattern.

Adult↗

Prevalence of moderate or severe left ventricular diastolic dysfunction in obese persons with obstructive sleep apnea.

We investigated prior to gastric bypass surgery the prevalence of left ventricular diastolic dysfunction (LVDD) by Doppler and tissue Doppler echocardiography in 14 obese women and in 6 obese men, mean age 45 years, with a mean body mass index of 49+/-5 kg/m2 who had nocturnal polysomnography for obstructive sleep apnea (OSA). The Doppler and tissue Doppler echocardiographic data were analyzed blindly without knowledge of the clinical characteristics or whether OSA was present or absent. Of 20 patients, 8 (40%) had no OSA, 4 (20%) had mild OSA, and 8 (40%) had moderate or severe OSA. Moderate or severe LVDD was present in 4 of 8 patients (50%) with moderate or severe OSA and in none of 12 patients (0%) with no or mild OSA (p<0.01). Obese patients with moderate or severe OSA have a higher prevalence of moderate or severe LVDD than obese patients with no or mild OSA.

Adult↗

Diastolic dysfunction and autonomic abnormalities in patients with systolic heart failure.

BACKGROUND: Patients with systolic heart failure (SHF) often have concomitant diastolic dysfunction (DD). SHF is associated with decreased heart rate variability (HRV), but the impact of degree of DD on HRV in SHF is unclear. METHODS AND RESULTS: HRV was measured in 139 patients, aged 64+/-12 years, 74% male, LVEF 30+/-8%. Patients had stable NYHA class II-III CHF on ACE inhibitors or ATII receptor blockers, with LVEF or=200 pg/ml. Subjects underwent 2-D echocardiography with Doppler assessment and 24-h Holters. Patients were categorized as having impaired relaxation (E-deceleration time>2 SD above age-adjusted normal values (AANV), E/A or=1; N=30), pseudonormal (E-deceleration time within 2 SD of AANV, E/A=1-2, systolic/diastolic pulmonary vein flow<1; N=25) or restrictive filling patterns (E-deceleration time>2 SD below AANV or/and E/A ratio>or=2; N=84) Differences were adjusted for clinical covariates using UNIANOVA, p<0.05. HRV was reduced and BNP higher in pseudonormal patients compared to impaired relaxation, but this difference was only significant for restrictive vs. impaired filling. Differences remained significant after adjustment for covariates. CONCLUSION: Significantly more abnormal HRV, reflecting greater cardiac autonomic dysfunction, is associated with restrictive DD compared to impaired relaxation.

Adult↗

Does intracoronary infusion of Fluosol-DA 20% prevent left ventricular diastolic dysfunction during coronary balloon angioplasty?

Distal intracoronary infusion of the perfluorochemical Fluosol-DA 20% has been shown to prevent systolic dysfunction during coronary artery balloon occlusion in coronary angioplasty. To assess its effect on global diastolic dysfunction, a randomized, single-blind, crossover protocol comparing intracoronary infusion of Fluosol or no infusion (control) was performed during 60 s balloon inflations in 10 patients (mean age 67 years) undergoing coronary angioplasty. Assessment of global systolic and diastolic function was obtained with high fidelity micromanometer measurements of left ventricular pressure. Eighteen pairs of balloon inflations (Fluosol versus control) were analyzed. Patients reported significantly less severe chest pain during inflations accompanied by Fluosol compared with control. However, during coronary balloon occlusion, no significant differences in the changes from baseline values were observed between Fluosol and control with regard to ventricular relaxation, including the time constant of early ventricular relaxation (tau) and maximal rate of fall in left ventricular pressure (maximal negative dP/dt). No differences between Fluosol and control were observed in terms of the increase in end-diastolic pressure or minimal diastolic pressure during balloon inflation. Mean systolic pressure decrease from baseline values was greater during control than during Fluosol inflations (-9.0 +/- 3.3 mm Hg, p = 0.013), but no significant difference was observed in the change in maximal rate of rise in left ventricular pressure (maximal positive dP/dt). These results suggest that Fluosol does not preserve global left ventricular diastolic function during coronary balloon occlusion, possibly because of its limited oxygen delivery capability relative to arterial blood.

Aged↗

Acute and chronic effects of oestradiol on left ventricular diastolic function in hypertensive postmenopausal women with left ventricular diastolic dysfunction.

BACKGROUND: Left ventricular function changes in the postmenopausal state. However, there are conflicting reports about the effects of oestrogen on left ventricular diastolic function in postmenopausal women. OBJECTIVE: To evaluate the acute and chronic effects of oestradiol in physiological doses on diastolic heart function in hypertensive postmenopausal women with left ventricular diastolic dysfunction. METHODS: A prospective, randomised, double blind, placebo controlled study was used to evaluate the effects of oestradiol in 34 hypertensive women with left ventricular dysfunction. The acute effects of a single 1 mg oral dose of oestradiol or placebo were determined after 90 minutes. The chronic effects of 1 mg oestradiol orally/day or placebo were determined after 12 weeks. Diastolic functional indices (mitral flow and pulmonary venous flow) were assessed by Doppler echocardiography. RESULTS: Though an appropriate serum concentration was achieved, no acute effect of oestradiol administration on left ventricular diastolic function was identified. After 12 weeks of treatment the following changes (mean (SD)) were identified in the oestradiol group: a decrease in isovolumic relaxation time from 127 (23) to 106 (16) ms (p < 0.001), and in the deceleration time of the mitral E wave from 260 (42) to 238 (20) ms (p < 0.05); and an increase in the E/A ratio from 0.8 (0.2) (basal) to 1.0 (0.2) after 12 weeks (p < 0.001). CONCLUSIONS: Hypertensive postmenopausal women who had hormone replacement therapy over a period of 12 weeks had significant improvement in left ventricular diastolic function. No changes were identified following acute administration.

Adult↗

[Left ventricular diastolic dysfunction in young people with type 1 diabetes mellitus. Associated factors].

AIM: The aim of our study was to evaluate left ventricular function of diastolic in young (< 40 years) asymptomatic patients with type 1 diabetes mellitus free of cardiovascular disease symptoms and to analyze the associated factors to the left ventricular diastolic dysfunction (LVDD) in these patients. PATIENTS AND METHODS: Thirty-five type-1 diabetic patients (mean age 27.8+/-7.5 years) old and 54 healthy controls (mean age 26.1+/-4.1 years) were studied. Anamnesis, physical exploration, general analytical studies, microalbuminuric and Doppler-echocardiographic studies were performed. RESULTS: The LVDD was present in 13 (37.1%) of the diabetic patients and none of the control patients. The ratio of peak early to peak late (atrial) filling velocity was significantly decreased in diabetic compared with control subjects (1.1+/-0.3 versus 1.5+/-0.2; p<0.01). The isovolumetric relaxation time was increased in diabetic patients compared with control subjects (104+/-11 versus 79+/-11; p<0.01). Diabetics with LVDD were older aged, predominantly males, had worse glucemic control, more alteration of lipidic metabolism and higher levels of microalbuminuria, than diabetics without LVDD. CONCLUSIONS: The LVDD is frequent in young diabetics free of cardiovascular disease symptoms. These studies suggest that because this patients were of older age, of the masculine sex with, poor glucemic control, altered lipidic metabolism, and microalbuminuria they might be a group that is associated with LVDD which, in the absence of cardiovascular disease, might be an early preclinical alteration, potentially related to subsequent development of diabetic cardiomyopathy.

Adolescent↗

Myocardial velocity gradient as a noninvasively determined index of left ventricular diastolic dysfunction in patients with hypertrophic cardiomyopathy.

OBJECTIVES: We investigated the utility of the peak negative myocardial velocity gradient (MVG) derived from tissue Doppler imaging (TDI) for evaluation of diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM). BACKGROUND: Hypertrophic cardiomyopathy is characterized by impaired diastolic function with abnormal stiffness and prolonged relaxation. However, it remains difficult to evaluate these defects noninvasively. METHODS: Both TDI and conventional echocardiography were performed in 36 patients with HCM and in 47 control subjects. Left ventricular (LV) pressure was measured simultaneously in all HCM patients and in 26 controls. RESULTS: The peak negative MVG occurred soon after the isovolumic relaxation period during the initial phase of rapid filling (auxotonic relaxation). It was significantly smaller in HCM patients than in control subjects (2.32 +/- 0.52/s vs. 4.82 +/- 1.15/s, p < 0.0001); the cutoff value for differentiation between all HCM patients and 47 normal individuals was determined as 3.2/s. Both the left ventricular end-diastolic pressure (LVEDP) (19.6 +/- 6.1 mm Hg vs. 6.5 +/- 1.7 mm Hg, p < 0.0001) and the time constant of LV pressure decay during isovolumic diastole (tau) (44.0 +/- 6.7 ms vs. 32.1 +/- 5.5 ms, p < 0.0001) were increased in HCM patients compared with controls. The peak negative MVG was negatively correlated with both LVEDP (r = -0.75, p < 0.0001) and tau (r = -0.58, p < 0.0001). CONCLUSIONS: A reduced peak negative MVG reflects both prolonged relaxation and elevated LVEDP. The peak negative MVG might thus provide a noninvasive index of diastolic function, yielding unique information about auxotonic relaxation in patients with HCM.

Adult↗

[Analysis of mitral annulus excursion with tissue Doppler echocardiography (tissue Doppler echocardiography = TDE). Noninvasive assessment of left ventricular, diastolic dysfunction].

BACKGROUND: Mitral inflow velocity, deceleration time, and isovolumic relaxation time recorded by Doppler echocardiography have been widely used to evaluate left ventricular diastolic function but are affected by age, heart rate, loading conditions, and other factors. The diastolic mitral anulus velocity assessed by tissue Doppler echocardiography (TDE) was suggested to provide additional information about LV relaxation less affected by filling pressures. AIM OF THE STUDY: This study was designed to assess the clinical utility of mitral anulus velocity in the evaluation of left ventricular diastolic function. PATIENTS AND METHODS: Three groups of patients with a systolic ejection fraction > 45% were separated: 10 normal volunteers (60 +/- 10 y, CON group), 15 asymptomatic patients with known coronary artery disease (60 +/- 11 y, CAD group) and 15 patients with long-term arterial hypertension and heart failure symptoms (58 +/- 9 y, HYP group). The mitral inflow profile (E, A, E/A) was measured by pulsed Doppler, and the deceleration time (DT) and the isovolumic relaxation period (IVRT) were calculated. Systolic, early, and late diastolic velocities of the septal mitral anulus (ST, ET, AT, ET/AT) were assessed by pulsed TDE. All study subjects had invasive measurements of left ventricular end diastolic filling pressures during left heart catheterization. RESULTS: In the AH group, ET (6.9 +/- 4.8 cm/s) and ET/AT (0.71 +/- 0.28) were reduced compared to the CON group (11.7 +/- 4.7 cm/s and 1.11 +/- 0.36, p < 0.05, respectively) and the CAD group (8.9 +/- 5.4 cm/s and 0.85 +/- 0.26, respectively, p = ns). The groups did not differ with respect to the mitral E/A ratio, the deceleration time and the isovolumic relaxation time. LVED in the HYP group (16 +/- 8 mm Hg) was elevated compared to the CON group (8 +/- 3, p < 0.05) and the CAD group (12 +/- 6 mm Hg, p = ns). No correlation was found between ET and LVED (r = 0.26). When the combination of mitral E/A ratio > 1 with LVED > or = 15 mm Hg was classified as pseudonormalization, the pseudonormalization could be identified by a peak early diastolic mitral anulus velocity (ET) < 7 cm/s and an ET/AT ratio < 1 with a sensitivity of 77% and a specificity of 88%. CONCLUSIONS: The early diastolic mitral anulus velocity assessed by TDE (ET) is a preload-independent index of LV relaxation. TDE permits the detection of diastolic dysfunction in patients with a pseudonormal mitral inflow and elevated filling pressures.

Adult↗

Natriuretic peptides in patients with diastolic dysfunction due to idiopathic dilated cardiomyopathy.

AIMS: The degree of systolic dysfunction does not always correlate with functional impairment in patients with congestive heart failure. In contrast, diastolic dysfunction correlates well with functional impairment. In heart failure, both elevation of N-terminal proatrial natriuretic peptide and B-type natriuretic peptide are markers of a poor prognosis. METHODS: We investigated 32 patients (26 male, 6 female; mean age 55+/-2 years) with dilated cardiomyopathy and sinus rhythm. M-mode echocardiography and 2D-echocardiography were carried out in each patient. Pulsed-wave Doppler inflow signals were obtained and the following parameters were measured: maximal E wave and maximal A wave velocity, E/A ratio, E wave deceleration time, A wave deceleration time. Immediately after echocardiography blood samples were collected from patients in the supine position. N-terminal proANP and brain natriuretic peptide were measured using a radioimmuno assay. RESULTS: The left ventricular ejection fraction was 34+/-1%, the left ventricular end-diastolic diameter on M-mode echocardiography was 68+/-1 mm, while left atrial diameter was 45+/-1 mm. Univariate analysis revealed a significant correlation between both left atrial diameter and ejection fraction and N-terminal proANP and brain natriuretic peptide. All transmitral Doppler parameters showed a significant correlation with N-terminal proANP and brain natriuretic peptide. On forward stepwise regression analysis, left atrial diameter and ejection fraction were able to predict both N-terminal proANP and brain natriuretic peptide. However, of the diastolic parameters only the E/A ratio remained significant. Mildly symptomatic patients differed significantly from severely symptomatic patients in all Doppler parameters. Mildly symptomatic patients had significantly lower levels of N-terminal proANP (0.571+/-0.079 vs 2.282+/-0.340 nmol. l(-1);P<0.001) and brain natriuretic peptide (51+/-14.8 vs 474.2+/- 86.8 pg. ml(-1);P<0. 001). CONCLUSION: There is a close relationship between natriuretic peptides and diastolic Doppler parameters of left ventricular filling in patients with dilated cardiomyopathy. There is also a significant difference between patients with mild and severe functional impairment regarding both natriuretic peptides and transmitral Doppler parameters.

Atrial Natriuretic Factor↗

Left ventricular diastolic dysfunction in patients with so-called lone atrial fibrillation.

Lone atrial fibrillation (AF) is defined by the absence of identifiable causes of AF, but its hemodynamics have not been investigated. Twenty-eight patients with lone AF were compared with 14 control patients referred for Wolff-Parkinson-White ablation. Transthoracic and transesophageal echocardiography were performed to rule out structural heart disease, followed by transseptally performed complete hemodynamic evaluation of the left heart systolic and diastolic function. There was no evidence of diastolic dysfunction according to echocardiographic criteria in AF and control patients. There was no difference in echocardiographic measurements, except for a significantly higher inferosuperior left atrial dimension seen in the four-chamber apical view in AF patients (51+/-10 vs 40+/-6 mm, P = 0.03). Hemodynamic evaluation showed that end-diastolic left ventricular pressure and the nadir of the left atrial Y descent were significantly higher in lone AF patients versus controls: 13+/-5 versus 8+/-3 mmHg (P = 0.001) and 6.7+/-3 versus 4.6+/-2.7 mmHg (P = 0.05). Our results demonstrated the presence of diastolic left heart dysfunction in patients with so-called lone AF.

Adult↗

Reversible diastolic dysfunction after successful coronary artery bypass surgery. Assessment by transesophageal Doppler echocardiography.

To assess the potential effects of coronary artery bypass surgery on left ventricular diastolic filling, 12 patients, aged 65 +/- 11 years, were studied by serial transesophageal Doppler echocardiograms. Doppler measures of mitral inflow velocity were made before, immediately after, 4 h after, and 20 h after cardiopulmonary bypass (CPB). Left atrial pressure was directly measured and controlled at 10 +/- 2 mm Hg for each study period. Mitral maximal early inflow velocity (E)/maximal atrial velocity (A) ratios and atrial filling fractions were calculated as indexes of diastolic function from maximal E and A velocities and their time velocity integrals, respectively. Data sets were available for serial comparison in 11 patients and were also compared with an age-matched control group of normal values. The results of E/A ratios were as follows: control group--1.4 +/- 0.2; before CPB--1.7 +/- 0.6; immediately after CPB--1.0 +/- 0.2 (p < 0.05 vs control group, before CPB, and 20 h after CPB values); 4 h after CPB--0.8 +/- 0.2 (p < 0.05 vs control group, before CPB, and 20 h after CPB values); and 20 h after CPB--1.3 +/- 0.4. Atrial filling fractions were as follows: control group--0.29 +/- 0.05; before CPB--0.25 +/- 0.06; immediately after CPB--0.43 +/- 0.07 (p < 0.05 vs control group, before CPB, and 20 h after CPB values); 4 h after CPB, 0.46 +/- 0.07 (p < 0.05 vs control group, before CPB, and 20 h after CPB values); and 20 h after CPB--0.35 +/- 0.06. Alterations in Doppler indexes of left ventricular filling occurred immediately after CPB and persisted 4 h after CPB. These indexes returned to baseline values by 20 h after CPB. This suggests reversible diastolic dysfunction in patients after coronary artery bypass surgery.

Adult↗

Factors contributing to left ventricular diastolic dysfunction in long-term type I diabetic subjects.

Although non-invasive studies in type I diabetic subjects indicate left ventricular (LV) diastolic dysfunction, the contribution of borderline or mild hypertension to such changes is obscure. Thus, digitized M-mode echocardiograms were obtained in 32 (18 men) young (less than 50 years) normotensive controls and 32 (21 men) long-term (greater than or equal to 12 years) type I diabetics with blood pressures ranging from normal to hypertensive. All diabetics were without clinical heart disease, none were previously treated for hypertension or using cardioactive drugs. Heart rate, systolic and diastolic blood pressures were higher in diabetic than control subjects. Their LV end-diastolic dimension was smaller, whereas wall thickness, LV mass index and fractional shortening were similar to controls. In diabetics, however, the normalized peak filling rate was decreased and the rapid filling period fraction of diastole increased. In multivariate analysis, diabetes and LV mass independently and inversely influenced the normalized peak filling rate, while fractional shortening did so positively. Furthermore, diabetes and systolic blood pressure independently influenced the rapid filling period fraction of diastole. This study is the first to demonstrate systolic blood pressure and LV mass as independent contributors to subclinical LV diastolic abnormalities in diabetics. These findings may therefore indicate the need to treat even mild hypertension in diabetics in an effort to delay the development of cardiopathy.

Adult↗

Diastolic dysfunction is not related to changes in glycaemic control over 6 months in type 2 (non-insulin-dependent) diabetes mellitus. A cross-sectional study.

Diastolic dysfunction may be the earliest marker of a diabetes-induced heart muscle disease which leads to the progressive development of cardiac failure. Left ventricular diastolic function was indirectly assessed using pulsed wave Doppler ultrasound mitral-flow velocities in 20 normotensive patients with a new diagnosis of type 2 diabetes mellitus, normal cardiac function and no evidence of coronary artery disease and in 16 age-matched normal subjects. Peak velocities of early (E) and late (A) left ventricular filling were measured. The median (interquartile ranges) peak E/A ratio was significantly reduced in the diabetic group 0.96 (0.8-1.2) vs 1.2 (1.1-1.3), P < 0.01. Despite improvements in glycaemic control over 3 months, HbA1c 9.9% (7.6%-10.5%) to 7.4% (6.5%-7.9%), P < 0.001, maintained at 6 months, HbA1c 7.0% (6.4%-7.3%), there were no changes in the E/A ratio, 0.96 (0.83-1.15) and 0.95 (0.83-1.17), respectively. Furthermore, there was no correlation between percentage change in HbA1c and E/A ratio over 6 months. The results of this study suggest that in patients with type 2 diabetes mellitus and normal systolic function, diastolic function was impaired at diagnosis and was not affected by an improvement in the glycaemic control.

Blood Glucose↗

Diastolic dysfunction in hypertrophic cardiomyopathy. Effect on active force generation during systole.

We tested the hypothesis that intracellular Ca++ [( Ca++]i) overload underlies the diastolic dysfunction of patients with hypertrophic cardiomyopathy. Myocardial tissue was obtained at the time of surgery or transplantation from patients with hypertrophic cardiomyopathy and was compared with control myocardium obtained from patients without heart disease. The isometric contractions and electrophysiologic properties of all myocardial specimens were recorded by standard techniques and [Ca++]i was measured with the bioluminescent calcium indicator aequorin. In contrast to the controls, action potentials, Ca++ transients, and isometric contraction and relaxation were markedly prolonged in the hypertrophic myocardium, and the Ca++ transients consisted of two distinct components. At 38 degrees C and 1 Hz pacing frequency, a state of relative Ca++ overload appeared develop, which produced a rise in end-diastolic [Ca++]i, incomplete relaxation, and fusion of twitches with a resultant decrease in active tension development. We also found that drugs with increase [Ca++]i, such as digitalis, exacerbated these abnormalities, whereas drugs that lower [Ca++]i, such as verapamil, or agents that increase cyclic AMP, such as forskolin, prevented them. These results may explain why patients with hypertrophic cardiomyopathy tolerate tachycardia poorly, and may have important implications with regard to the pharmacologic treatment of patients with hypertrophic cardiomyopathy.

Adult↗

Enalapril does not improve left ventricular diastolic dysfunction in young and mild hypertensives without concomitant hypertrophy.

The aim of the study was to determine whether enalapril monotherapy can improve left ventricular diastolic dysfunction (LVDD) in young and mild hypertensive patients without concomitant left ventricular hypertrophy (LVH). Fifty patients with hypertension < or = 160/100 mm Hg, aged < or = 50 years, normal two-dimensional echocardiographic (2-D echo) measurements, and LVDD were enrolled in this study. The LVDD was defined as a transmitral early (E) to atrial (A) peak velocity ratio of < or = 1. The mean documented hypertension was 6.3 years. The mean daily dose of enalapril was 13 mg. Baseline and 24-month follow-up echocardiograms were evaluated. Thirty-eight age- and sex-matched healthy subjects served to establish the normal reference values of 2-D echo measurements. After treatment, peak early diastolic velocity (E) (49 +/- 6 cm/sec v 48 +/- 10 cm/sec; P = not significant), peak atrial velocity (A) (62 +/- 9 cm/sec v 62 +/- 10 cm/sec; P = not significant), and E/A ratio (0.80 +/- 0.10 v 0.78 +/- 0.13; P = not significant) remained unchanged. Moreover, early to atrial velocity-time integral ratio (1.24 +/- 0.08 v 1.23 +/- 0.11; P = not significant) did not change. The left ventricular mass index, relative wall thickness, left ventricular end-systolic diameter, left atrial diameter, fractional shortening, heart rate, and body mass index did not show significant changes in all hypertensive patients. In conclusion, long-term antihypertensive therapy with enalapril did not lead to an improvement of LVDD in young and mild hypertension patients without concomitant LVH.

Adult↗

Relationship between insulin resistance and left ventricular diastolic dysfunction in patients with impaired glucose tolerance and type 2 diabetes.

AIM: The aim of this study was to explore the relationship between insulin resistance (IR) and the left ventricular diastolic function in patients with type 2 diabetes and subjects with impaired glucose tolerance (IGT). METHODS: The study included 119 subjects who underwent oral glucose tolerance test (OGTT). IR was assessed using Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and Quantitative Insulin Sensitivity Check Index (QUICKI). Left ventricular diastolic function was assessed using trans-thoracic Doppler echocardiography. RESULTS: Based on the OGTT results, 29 subjects had normal glucose tolerance (NGT), 20 subjects had impaired glucose tolerance (IGT), and 70 patients had type 2 diabetes. There were significant differences among the patients in groups with NGT, IGT and diabetes regarding HOMA-IR (4.20 +/- 1.20 vs. 6.45 +/- 3.83 vs. 8.70 +/- 6.26; P < 0.001) and QUICKI (0.54 +/- 0.11 vs. 0.49 +/- 0.08 vs. 0.47 +/- 0.08; P < 0.001). In subjects with NGT, IGT and patients with diabetes, the pulsed Doppler transmitral variables were: E-wave (0.72 +/- 0.16 cm/s vs. 0.62 +/- 0.13 cm/s vs. 0.58 +/- 0.17 cm/s; P < 0.001), A-wave (0.61 +/- 0.13 cm/s vs. 0.62 +/- 0.11 cm/s vs. 0.71+/- 0.14 cm/s; P = 0.006) and E/A ratio (1.22 +/- 0.33 vs. 1.02 +/- 0.24 vs. 0.85 +/- 0.26; p < 0.001). The proportion of subjects with an E/A ratio <1 was 27.6% in the group with NGT, 55% in the group with IGT and 75.7% in the group with diabetes (P < 0.001). The E/A ratio correlated with HOMA-IR (r = -0.30, p = 0.001) and QUICKI (r = 0.37, p < 0.0001). Multiple linear regression model showed that IR (assessed by QUICKI) was an independent correlate of diastolic dysfunction (P = 0.034). CONCLUSIONS: In subjects with impaired glucose tolerance and patients with type 2 diabetes, insulin resistance is associated with impaired diastolic function of the left ventricle.

Anthropometry↗