Changes in Early and Late Diastolic Filling Patterns Induced by Long-term Adrenergic β-Blockade in Patients With Idiopathic Dilated Cardiomyopathy

Abstract

Background β-Blockers have been used in patients with idiopathic dilated cardiomyopathy to improve cardiac performance and theoretically would be beneficial to diastolic function. However, there are few reports on changes in diastolic function during chronic pharmacological treatment of congestive heart failure. Methods and Results The present study was a substudy in the international Metoprolol in Dilated Cardiomyopathy Trial. Transmitral Doppler echocardiography was used to evaluate diastolic function in 77 patients randomly assigned to placebo (n=37) or metoprolol (n=40). The patients were treated for 12 months. Changes in Doppler flow variables in the metoprolol group implied a less restrictive filling pattern, expressed as an increase in E-wave deceleration time (placebo, 185±126 to 181±64 ms; metoprolol, 152±63 to 216±78 ms; P =.01, placebo versus metoprolol). Maximal increase in deceleration time had occurred by 3 months, whereas systolic recovery was achieved gradually and maximal effect was seen by 12 months of treatment. Although deceleration time was correlated to heart rate at baseline, changes in deceleration time were not significantly correlated to changes in heart rate during treatment. Conclusions During the first 3 months of treatment, maximal effects on diastolic variables were reached, whereas the most prominent effect on systolic function was seen late in the study. It is suggested that effects on diastolic filling account for subsequent later myocardial systolic recovery. The E-wave deceleration time, which in recent studies has been shown to be a powerful predictor of survival, was significantly improved in the metoprolol-treated patients.

Effects of β-Adrenergic Blocking Therapy on Left Ventricular Diastolic Relaxation Properties in Patients With Dilated Cardiomyopathy

“…This is supported by recent data demonstrating the important interplay of sarcoplasmic reticulum calcium ATPase and the Na ϩ -Ca 2ϩ exchanger in determining diastolic force in isolated muscle strips from patients with end-stage heart failure. 32 The nearly universal increase in LV systolic pressure and decrease in end-diastolic pressure, coupled with an improvement in LV ejection fraction 2,20 ; our observations and those of others 2,6 of an improvement in early, active isovolumic relaxation; and the additional finding in this investigation of improvement in late, passive diastolic relaxation properties, particularly myocardial stiffness, all suggest that ␤-adrenergic blocking therapy in these patients may beneficially affect calcium homeostasis.…”

“…Subsequently, the MDC Study Group evaluated LV diastolic filling using transmitral Doppler echocardiography. 6 They reported that metoprolol resulted in a significant improvement in early LV diastolic deceleration times in cardiomyopathy patients. The maximum improvement in deceleration times occurred within 3 months of initiation of therapy, whereas LV systolic performance continued to improve for up to 12 months.…”

“…2,5,6,20 Waagstein and colleagues 1 initially reported improvement in LV end-diastolic pressure with metoprolol. Subsequently, the MDC Study Group evaluated LV diastolic filling using transmitral Doppler echocardiography.…”

“…Some data suggest that active, early isovolumic relaxation is improved with ␤-adrenergic blocking therapy, but the effect on late, passive relaxation properties remains unresolved. 2,5,6 Accordingly, the purpose of this investigation was to test the hypothesis that the salutary effect of ␤-adrenergic blocking therapy on LV end-diastolic pressure in cardiomyopathy patients is indicative of an improvement in late, passive relaxation properties.…”

Congestive heart failure. Correlation between functional class and systolic and diastolic functions assessed by Doppler echocardiography

“…According to several studies [20][21][22][23][24][25][26][27] , other factors, such as the use of correct medication, especially angiotensin converting enzyme inhibitors, may also influence functional class. In the present study, 56% of the patients regularly used some type of angiotensin converting enzyme inhibitor, without differences between groups.…”