UMM Logo

Universitas Muhammadiyah Malang

Free Download Journals Directory

International Journal of Medical Sciences

Different effect of exercise on left ventricular diastolic time and interventricular dyssynchrony in heart failure patients with and without left bundle branch block

Gunnar Plehn
, Julia Vormbrock, Thomas Butz, Martin Christ, Hans-Joachim Trappe and Axel Meissner
Abstract :

Background: In patients with idiopathic dilated cardiomyopathy (IDCM) a prolongation of left ventricular (LV) systole at the expense of diastolic time was demonstrated. Our study was aimed to evaluate the effect of exercise on heart rate corrected diastolic time in controls, IDCM with and without LBBB, and patients with LBBB and normal LV function. Methods: 47 patients with IDCM, 30 without LBBB, and 17 with LBBB as well as 11 with isolated LBBB were studied during exercise using a combined hemodynamic-radionuclide angiographic approach. The phases of the cardiac cycle were derived with high temporal resolution from the ventricular time-activity curve. The loss of diastolic time per beat (LDT) was quantified using a regression equation obtained from a control group (n=24). Results: A significant LDT was demonstrated at rest and during peak exercise in IDCM patients with LBBB (39.1±32 and 37.3±30 ms; p < 0.001). In IDCM patients with normal activation LDT was unaffected at baseline, but elevated during peak exercise. This response was paralleled by an increase in interventricular mechanical dyssynchrony. Conclusion: During exercise an abnormal shortening of LV diastolic time is a common characteristic of heart failure patients which can be explained by the high prevalence of mechanical dyssynchrony.

Keywords :
diastolic time, heart failure, left bundle branch block, exercise test, interventricular dyssynchrony

Date Deposited : 28 Jul 2011 12:38

Last Modified : 28 Jul 2011 12:38

Official URL:

Volume 5, Number 6, - 2008 , ISSN 1449-1907

Full Text Original
Abstract : pdf doc