The prognostic value of myocardial viability recognized by low dose dipyridamole echocardiography in patients with chronic ischaemic left ventriculardysfunction

Aims The aim of this study was to assess the prognostic value of myocardial viability recognized as a contractile response to vasodilator stimulation in patients with left ventricular dysfunction in a large scale, prospective , multicentre, observational study. Methods and Results Three hundred and seven patients (mean age 60 +/- 10 ye ars) with angiographically proven coronary artery disease, previous (>3 mon ths) myocardial infarction and severe left ventricular dysfunction (ejectio n fraction <35%; mean ejection fraction: 28+/-7%) were enrolled in the stud y. Each patient underwent low dose dipyridamole echo (0.28 mg. kg(-1) in 4 min). Myocardial viability was identified as an improvement of <greater tha n or equal to> 0.20 in the wall motion score index. By selection, all patie nts were followed up for a median of 36 months. One-hundred and twenty-four were revascularized either by coronary artery bypass grafting (n=83) or co ronary angioplasty (n=41). The only end-point analysed was cardiac death. I n the revascularized group, cardiac death occurred in one of the 41 patient s with and in 16 of the 83 patients without a viable myocardium (2.4% vs 19 .3%, P<0.01). Outcome, as estimated by Kaplan-Meier survival, was better fo r patients with, compared to patients without, a viable myocardium, who und erwent coronary revascularization (97.6 vs 77.4%, P=0.01). Using a Cox prop ortional hazards model, the presence of myocardial viability was shown to e xert a protective effect on survival (chi-square 4.6, hazard ratio 0.1, 95% CI 0.01-0.8, P<0.03). The survival rate in medically treated patients was lower than in revascularized patients irrespective of the presence of a via ble myocardium (79.7% vs 86.2, P=ns). Conclusion In severe left ventricular ischaemic dysfunction, myocardial via bility, as assessed by low dose dipyridamole echo, is associated with impro ved survival in revascularized patients. (Eur Heart J 2001; 22: 837-844, do i: 10,1053/euhj.2000.2322) (C) 2001 The European Society of Cardiology.