Effect of revascularizing viable myocardium on left ventricular diastolic function in patients with ischaemic cardiomyopathy

Abstract

In patients with ischaemic left ventricular (LV) dysfunction and viable myocardium, revascularization improves systolic function. Diastolic dysfunction is also present in such patients; however, whether revascularization improves diastolic function also is largely unknown. Twenty-six patients with chronic ischaemic cardiomyopathy [ejection fraction (EF) 32 +/- 6%, wall motion score index (WMSI) 2.45 +/- 0.33] and viable myocardium (low-dose dobutamine echocardiography) were examined at baseline and > or =4 months after revascularization. Diastolic function was assessed by transmitral pulsed-wave Doppler and tissue Doppler imaging (TDI) at the mitral annulus. At baseline, 62% of patients showed non-restrictive filling (non-RF) pattern, and 38% restrictive filling (RF) pattern. After revascularization, along with improvement in systolic function (EF 43 +/- 10%, WMSI 1.78 +/- 0.47, P = 0.0002 for both), diastolic filling improved in most patients, with only three patients still exhibiting RF pattern (P = 0.016); furthermore, E' velocity increased (32 +/- 42%, P = 0.0028) and E/E' decreased (-19 +/- 31%, P = 0.0378) compared with baseline. Left ventricular filling pressure also decreased, from 17.5 +/- 6.8 to 13.1 +/- 6.5 mmHg (P = 0.005). Improvement of diastolic function by TDI was related to the extent of viability at baseline (P = 0.0098) and to LV reverse remodelling after revascularization (P = 0.0092). In patients with ischaemic cardiomyopathy, LV diastolic filling may largely improve after revascularization. Improvement of diastolic dysfunction is related to the amount of viable tissue and it may represent an additional advantage of revascularizing dyssinergic but viable myocardium.