Left ventricular mechanical dyssynchrony impairs exercise capacity in patients with coronary artery disease with preserved left ventricular systolic function and a QRS duration ≤ 120 ms
التفاصيل البيبلوغرافية
العنوان:
Left ventricular mechanical dyssynchrony impairs exercise capacity in patients with coronary artery disease with preserved left ventricular systolic function and a QRS duration ≤ 120 ms
Background: Left ventricular (LV) mechanical dyssynchrony can lead to impairment of LV function and is associated with adverse clinical outcomes in coronary artery disease (CAD) patients. The impact of LV dyssynchrony on exercise capacity (EC) in patients with CAD was investigated. Methods and Results: An echocardiographic examination with tissue Doppler imaging and exercise treadmill testing in 151 CAD patients with normal LV ejection fraction was performed. LV intra- and inter-ventricular dyssynchrony were defined by the standard deviation of time interval between LV 6 basal segments (Ts-SD), and the time interval from the right ventricular (RV) free wall to LV lateral wall (Ts-RV) respectively, and EC was measured as metabolic equivalents (METs) on the treadmill. Patients with impaired EC (defined by a METs ≤8, which is the mean MET of the study population) were older (71±7 vs. 62±2 years, P