Evaluation of Left Ventricular Dyssynchrony after Coronary Artery Bypass Grafting in Patients with Ischemic Left Ventricular Dysfunction

Background: Ischemic left ventricular (LV) dysfunction is one of the major causes of LV dyssynchrony. This is indicative of poor prognosis in patients with LV dysfunction and correction of ischemia by Coronary Artery Bypass Grafting (CABG) may resynchronize LV contraction. The aim of this study was to evaluate the effect of CABG on LV dyssynchrony, systolic and diastolic function. Patients: The present study comprised 31 patients with ischemic LV dysfunction with Ejection Fraction (EF: 25-50%). Echocardiography with Tissue Doppler Imaging (TDI) was performed to assess LV dyssynchrony (calculated by basal LV segment), to evaluate diastolic function by measurement of peak early diastolic mitral annular velocity (E-m), systolic function by measurement of peak early systolic mitral annular velocity (S-m) and Ejection Fraction (EF) by Simpson method. Results: Mean LV dyssychrony before CABG was 30 +/- 16 ms that decreased to 22 +/- 14 ms after operation (P=0.04). There was also improved diastolic and systolic function after CABG (E-m 0.04m/s versus 0.05 m/s, P=0.01 and S-m 0.06 m/s versus 0.08 m/s P=0.01). The mean ejection fraction rose from 40 +/- 8.6% to 42 +/- 8.2% (P=0.01). Conclusion: CABG is associated with improvement of LV dyssynchrony, systolic and diastolic function in patients with ischemic LV dysfunction.