Left ventricular filling and ventricular diastolic performance after percutaneous balloon mitral valvotomy.

The time course of left ventricular (LV) filling and LV diastolic performance were examined in 27 consecutive patients in sinus rhythm before and acutely after balloon mitral valvotomy (BMV). The mitral valve area acutely increased from 1.1 +/- 0.3 to 2.1 +/- 0.8 cm2. Simultaneous pressure-volume data were obtained using digital subtraction left ventriculography and LV micromanometer pressure before and 10 minutes after BMV. The time constant of LV isovolumic relaxation was unchanged after BMV (50 +/- 10 ms before BMV vs 47 +/- 13 ms after BMV). In addition, values before and after BMV for LV end-diastolic volume (123 +/- 29 vs 125 +/- 36 ml), end-diastolic pressure (11 +/- 4 vs 12 +/- 4 mm Hg) and diastolic filling time (337 +/- 126 vs 338 +/- 152 ms) were not altered by the procedure. After BMV the peak diastolic filling rate (403 +/- 143 vs 469 +/- 302 ml/s) was maintained despite a 36% reduction in left atrial filling pressure. There was a trend toward earlier occurrence of the peak filling rate (196 +/- 127 vs 146 +/- 148 ms, p = 0.08). The percentage of diastolic filling in the first third of diastole, however, was similar (42 +/- 9 vs 48 +/- 16%) before and after the procedure. Thus, the time course of LV filling is not significantly altered acutely after BMV, but is maintained at reduced left atrial filling pressure. Neither LV relaxation or LV chamber compliance are altered acutely after BMV.(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular diastolic performance in breast cancer survivors treated with anthracyclines

OBJECTIVE: The aim of our study was to evaluate left ventricular diastolic and systolic performance in women diagnosed with breast cancer and treated with low doses of anthracyclines (epirubicin). METHODS AND RESULTS: Thirty-four female patients with breast cancer treated with epirubicin up to 450 mg/m2 (study group), and a matched control group of 34 women diagnosed with breast tumours, who had not started chemotherapy, were assessed by echocardiography. Left ventricular diastolic function was evaluated by measuring Doppler transmitral flow: the maximal velocity of the E and A waves (rapid filling and atrial filling), the Emax/Amax ratio, the pressure half time (PHT) of the E wave and the isovolumic relaxation time (IVRT). The left ventricular ejection fraction was calculated to assess systolic performance. We documented a significant decrease of Emax, whereas the A wave was significantly increased in the study group compared to the control group. The mitral E/A ratio was below 1 in the study group. Prolonged PHT and IVRT were also detected in the epirubicin-treated group when compared with the control group. Left ventricular systolic performance was not significantly altered in the study group in comparison with the control group. Although the ejection fraction was lower in the study group the difference did not reach statistical significance. CONCLUSION: Our study certified impaired left ventricular diastolic performance in patients with breast cancer treated with low total doses of epirubicin (< or = 450 mg/m2). We concluded that diastolic impairment is due to poor left ventricular compliance being an early marker of epirubicin cardiotoxicity that precedes systolic function alterations.     

Left ventricular diastolic capacity in man

Plasma volume expansion with 500 ml of low-molecular-weight dextran was used in 27 patients (nine normal subjects, 13 patients with ischemic heart disease, four with aortic stenosis and one with cardiomyopathy) to increase left ventricular end-diastolic pressure (LVEDP) from a control value of 12.4 +/- 7.0 mm Hg (mean +/- SD) to 23.3 +/- 7.0 mm Hg and end-diastolic volume (EDV) from 84.0 +/- 23.8 ml/m2 to 97.6 +/- 22.9 ml/m2. EDV-LVEDP curves constructed for 12 patients from multiple angiograms at progressively increasing LVEDPs during plasma volume expansion showed an initial part where EDV increased in parallel with LVEDP and a final steep or perpendicular part where EDV increased minimally or not at all as LVEDP exceeded 20 mm Hg. Exponential equations were used to fit diastolic volume-pressure data obtained with catheter-tip manometers in seven patients: the exponential constant, k, was 0.012-0.044 ml-1 and was inversely related to EDV (Spearman's rank correlation coefficient = -1). For comparable EDV, there were no differences in k values between normal subjects and patients with a variety of heart diseases.     

Left ventricular diastolic function in hypertrophic cardiomyopathy

Impaired diastolic function of the hypertrophied and stiffened left ventricle is a characteristic feature of hypertrophic cardiomyopathy (Figure 1). Altered left ventricular filling dynamics and reduced left ventricular distensibility or increased left ventricular diastolic chamber stiffness are associated with reduced left ventricular stroke volume, increased left ventricular filling pressures and compressive effects on the coronary microcirculation. These factors contribute importantly to the clinical presentation of many patients, including symptoms of fatigue, dyspnea and angina pectoris. Reduced distensibility results both from factors determining the passive elastic properties of the ventricular chamber (including severity of hypertrophy, fibrosis and cellular disarray) and from factors influencing the rate and extent of active left ventricular relaxation (Figure 2). The factors contributing to impaired relaxation in hypertrophic cardiomyopathy are mediated via either inactivation dependent or load-dependent mechanisms. In laboratory animals, compromise of myocardial inactivation results in a persistent increase in intracellular calcium concentration and in prolonged interaction of the contractile proteins. Additionally, there is evidence for an increased number of active receptors for calcium antagonists and, lastly, for myocardial ischemia (Figure 3). Load-dependent mechanisms include diminished wall tension at the opening of the mitral valve, changes in afterload, contractility and coronary flow. Other factors are nonuniform and asynchronous regional ventricular function due to differing increases in thickness of the ventricular walls and ischemia (Figure 4). Calcium channel blockers exert a favorable influence on left ventricular relaxation and filling (Figure 5); verapamil and diltiazem are preferable to nifedipine. Verapamil increases left ventricular stroke volume without an increase in the end-diastolic pressure (Figure 6), reduces regional asynchrony if present, and leads to a more homogeneous regional diastolic filling (Figure 4).(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular diastolic function in mitral stenosis

The assessment of left ventricular (LV) function in the setting of mitral stenosis (MS) has been critically examined for decades. Accurate assessment of aberrations in diastolic function is important as these subjects often present with signs and symptoms of heart failure and pulmonary congestion that cannot be solely explained by the severity of mechanical obstruction. Echocardiographic evaluation of diastolic dysfunction includes an evaluation of reduced LV compliance, diminished restoring forces, and enhanced stiffness, which are challenging in the setting of MS owing to altered hemodynamic loading. Conventional echocardiographic and Doppler measures offer limited information. Novel assessments employing speckle tracking echocardiography are relatively less studied. A more comprehensive assessment including clinical evaluation, identification of concomitant disorders, and comorbidities is particularly warranted in older subjects with degenerative MS to suspect diastolic dysfunction and arrive at optimal medical therapy or intervention. This review provides an overview of etiological, pathophysiological, echocardiographic, and invasive assessment of diastolic dysfunction in the setting of MS, with specific focus on strengths and limitations of available echocardiographic and Doppler techniques.     

Left ventricular diastolic function in weight lifters

Concentric left ventricular (LV) hypertrophy and asymmetric septal hypertrophy have both been described in weight lifters, but diastolic filling, which is abnormal in pathologically hypertrophied ventricles, has not been investigated in such subjects. Accordingly, pulsed Doppler examination of LV inflow, M-mode and 2-dimensional echocardiography were performed in 16 competitive weight lifters and 10 age-matched male control subjects. Peak and mean filling rates were determined in milliliters per second as the product of the cross-sectional area of the mitral anulus and the Doppler-derived peak early and mean transmitral inflow velocities, respectively. Rapid filling index was defined as peak filling rate divided by mean filling rate. Flow velocity integrals of the early and atrial diastolic filling phases were also measured. LV end-diastolic volume and ejection fraction were measured using 2-dimensional echocardiography. Weight lifters had significantly higher LV end-diastolic volume (181 ± 50 vs 136 ± 40 ml, p < 0.05) and dimension (5.6 ± 0.6 vs 5.1 ± 0.5 cm, p < 0.05), and posterior wall thickness (0.9 ± 0.2 vs 0.8 ± 0.1, p < 0.05); however, after correction for body surface area there was no significant difference in these values. Weight lifters had significantly higher LV mass (241 ± 70 vs 165 ± 29, p < 0.02) and LV mass index (114 ± 29 vs 87 ± 15 g/m², p < 0.05). There was no significant difference between the weight lifters and control subjects in rapid filling index, early to late integral ratio or ejection fraction. Five of the weight lifters competed nationally and took steroids heavily; in this group diastolic function was abnormal. Thus, weight lifters have concentric LV hypertrophy but normal diastolic function, consistent with physiologic hypertrophy.     

Left ventricular diastolic function in systemic sclerosis

OBJECTIVE: To assess left ventricular diastolic function in patients with systemic sclerosis (SSc) and to verify if a "primary" diastolic dysfunction might exist. METHODS: In total 124 patients and 41 healthy subjects underwent complete echocardiographic examination. The following pulsed wave Doppler variables were evaluated: peak velocity during early filling (E), peak velocity during late atrial filling (A), E/A ratio, and early filling deceleration time. RESULTS: Seventy-seven patients (62.1%) had conditions potentially affecting left ventricular diastolic function (Group A) and 47 patients (37.9%) formed a homogeneous group without cardiac involvement or other causes of abnormal diastolic function (i.e., systemic and/or pulmonary hypertension, ventricular hypertrophy, pericardial disease, systolic dysfunction, valvular heart disease, coronary artery disease) (Group B). The entire SSc population and Group A showed significant differences in the Doppler variables of diastolic function compared to the control group. No significant differences were found between Group B and controls. CONCLUSION: In patients with SSc, left ventricular diastolic dysfunction was found only in patients with conditions potentially affecting left ventricular diastolic function. In patients without conditions potentially affecting left ventricular diastolic function no differences were seen in comparison with controls. SSc does not seem to cause "primary" diastolic abnormalities.     

Left ventricular diastolic dysfunction in Ebstein's anomaly

This study was performed to evaluate left ventricular (LV) diastolic function in patients with Ebstein's anomaly using Doppler echocardiography. We found that LV abnormal relaxation in this anomaly cannot be explained by right ventricular volume overload alone. Furthermore, LV diastolic dysfunction persists even after intracardiac repair.     

Left ventricular diastolic dysfunction in patients with subclinical hypothyroidism.

Although subclinical hypothyroidism is frequently diagnosed, the decision to institute a substitutive therapy with L-T4 remains controversial. Because the cardiovascular system is considered a main target for the action of thyroid hormone, we investigated whether subclinical hypothyroidism induces cardiovascular abnormalities. Twenty-six patients (mean age, 36 +/- 12 yr) were evaluated by Doppler-echocardiography, whereas a subgroup of 10 patients, randomly selected, were reevaluated after 6 months of L-T4 substitutive therapy (mean dose, 68 microg daily). Thirty subjects (matched for age, sex, and body surface area) served as controls. Mean plasma TSH was significantly higher in patients (P < 0.001), whereas mean serum free T4 and free T3 concentrations, although in the normal range, were significantly lower (P < 0.001 and P < 0.005, respectively). Blood pressure and heart rate did not differ from control values. Echocardiogram examination showed no abnormalities of the left ventricular morphology and a slight, but not significant, reduction in the systolic function in the patient group. In contrast, Doppler-derived indices of diastolic function showed significant prolongation of the isovolumic relaxation time (94 +/- 13 vs. 84 +/- 8 msec; P < 0.001), increased A wave (55 +/- 13 vs. 48 +/- 9 cm/sec; P < 0.05), and reduced early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.4 +/- 0.3 vs. 1.7 +/- 0.3; P < 0.001). In the subgroup of 10 patients, thyroid hormone profile was normalized by 6 months of L-T4 substitutive therapy, whereas no changes were observed in the left ventricular morphology. Systolic function was significantly enhanced, as compared with pretreatment values (P < 0.01) but did not differ from control values. Also, systemic vascular resistance was significantly decreased by L-T4 replacement therapy. Assessment of diastolic function showed significant shortening of isovolumic relaxation time (77 +/- 15 vs. 91 +/- 8; P < 0.05), reduction of A wave (51 +/- 13 vs. 60 +/- 12; P < 0.01), and increase of early diastolic mitral flow velocity/late diastolic mitral flow velocity ratio (1.7 +/- 0.4 vs. 1.3 +/- 0.3; P < 0.001). These indices, however, were comparable with those of control subjects. These findings indicate that subclinical hypothyroidism affects diastolic function and that this abnormality may be reversed by L-T4 substitutive therapy.     

Left ventricular passive diastolic properties in chronic mitral regurgitation.

BACKGROUND. In chronic mitral regurgitation, the myocardium responds to the increased filling volume by geometric alteration and eccentric hypertrophy. This study was designed to evaluate the effects of a pure volume overload on left ventricular diastolic chamber and myocardial properties and to assess the relation of passive diastolic function to systolic ejection performance. METHODS AND RESULTS. By use of simultaneous cineangiography and left ventricular micromanometry, left ventricular passive diastolic stiffness was evaluated in nine normal controls (group 1), 14 patients with chronic mitral regurgitation and a normal ejection fraction (greater than or equal to 57%, group 2), and 13 patients with mitral regurgitation and a reduced ejection fraction (less than 57%, group 3). Passive diastolic function was evaluated by using a three-constant elastic model. Left ventricular chamber properties were represented by the relation of pressure to volume; myocardial properties were evaluated by relating myocardial midwall stress to midwall strain. The constant of left ventricular chamber stiffness was decreased in group 2 compared with controls (p less than 0.05) but it was normal in group 3. The constant of myocardial stiffness was increased in group 3 compared with groups 1 and 2 (p less than 0.01). Among patients with mitral regurgitation, there was a significant inverse relation between ejection fraction and the constant of myocardial stiffness (r = -0.83). CONCLUSIONS. The chronic adaptation to volume overload in chronic mitral regurgitation tends to decrease left ventricular chamber stiffness. Patients with mitral regurgitation and a depressed ejection fraction demonstrated diastolic myocardial dysfunction. Compromised diastolic function in patients with chronic mitral regurgitation and reduced systolic performance may contribute to the clinical manifestations of congestive heart failure.     

Left ventricular diastolic function and cardiac performance during exercise in patients with acromegaly

Exercise-induced impairment of left ventricular (LV) ejection fraction is common in patients with acromegaly and normal resting systolic function. This study aimed to clarify whether diastolic dysfunction plays a role in the abnormal adaptation to exercise in these patients. Forty-eight patients with active acromegaly underwent LV radionuclide angiography at rest and during exercise. Doppler echocardiography was also performed to assess LV mass index and diastolic function by combined analysis of mitral and pulmonary flow velocity curves. LV ejection fraction at peak exercise was related to rest ejection fraction (r = 0.78; P < 0.001), peak filling rate (r = 0.55; P < 0.01), LV mass index (r = -0.56; P < 0.001), and the difference between duration of diastolic reverse pulmonary vein flow and mitral flow at atrial contraction (Delta duration) (r = -0.54; P < 0.01). At stepwise regression analysis, rest ejection fraction and Delta duration were the only variables that independently influenced (P < 0.001) ejection fraction at peak exercise. Diastolic dysfunction is important in determining cardiac performance during exercise in patients with acromegaly and normal resting systolic function. Combined analysis of pulmonary vein and mitral flow velocity curves allows the identification of impaired LV diastolic function in such patients.     

Left ventricular diastolic filling in patients with left ventricular dysfunction

The pattern of abnormal left ventricular diastolic filling and its specificity in coronary disease patients with severe left ventricular dysfunction has received little attention. We evaluated the left ventricular diastolic filling curve derived from gated blood pool scans in 21 normals, 61 coronary disease patients with ejection fractions less than or equal to 30%, and 51 congestive cardiomyopathy patients with ejection fraction less than or equal to 30%. The peak filling rate (PFR), peak ejection rate (PER), PFR/PER and the % stroke volume filled at 1/3 of diastole (%SV-1/3 DT) and at the end of the rapid filling period (%SV-RFP) were determined for each group. The PFR and PER were reduced in both coronary disease and congestive cardiomyopathy groups. The PFR/PER was increased in the coronary disease group (1.19 +/- 0.28) and congestive cardiomyopathy group (1.21 +/- 0.32) as compared to normals (0.93 +/- 0.20, P less than 0.001). A greater %SV-1/3 DT and %SV-RFP were noted in both coronary disease and congestive cardiomyopathy groups. Coronary disease and congestive cardiomyopathy patients with a mean pulmonary capillary pressure (PCP) greater than or equal to 18 mm Hg had a greater PFR/PER, %SV-1/3 DT, and %SV-RFP than patients with a PCP less than 18 mm Hg. An abnormal and nonspecific pattern of left ventricular diastolic filling is present in both coronary disease and congestive cardiomyopathy patients and is characterized by an increased PFR/PER, a greater %SV-1/3 DT, and a greater %SV-RFP. This pattern may be related to elevated PCPs.     

Left ventricular systolic and diastolic function in hyperthyroidism

In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive lodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle.     

Left ventricular diastolic pulsus alternans in hypertrophic cardiomyopathy

Summary We examined left ventricular (LV) diastolic pulsus alternans associated with systolic pulsus alternans in a patient with hypertrophic cardiomyopathy. Alternation in abnormal LV diastolic pressure waveforms persistently declining into mid-diastole (incomplete relaxation) and normal diastolic pressure were noted. Diastolic pulsus alternans was not corrected by isoproterenolol and may possibly be independent of systolic pulsus alternans.     

Left ventricular diastolic collapse in low-pressure cardiac tamponade

A case of systemic hypotension with volume depletion not responding to intravenous fluids was found to have features of cardiac tamponade on two-dimensional (2-D) echocardiography. Intracardiac pressures were normal on cardiac catheterization. An interesting observation was the presence of left ventricular (LV) collapse on 2-D echocardiography. To the authors' best knowledge, such a case of low-pressure cardiac tamponade with LV collapse has not been reported earlier.