Prediction of functional recovery of viable myocardium after delayed revascularization in postinfarction patients : Accuracy of dobutamine stress echocardiography and influence of long-term vessel patency

OBJECTIVES We sought to evaluate Dobutamine stress echocardiography (DSE) for predicting recovery of viable myocardium after revascularization with cineangiography as gold standard for left ventricular (LV) function. We studied the influence of late vessel reocclusion on regional LV function. BACKGROUND Dobutamine stress echocardiography is well established evaluation method for myocardial viability assessment. In previous studies the reference method for assessing LV recovery was echocardiography; long-term vessel patency has not been systematically addressed. METHODS Sixty-eight patients with first acute myocardial infarction (AMI) and residual stenosis of the infarct related artery (IRA) underwent DSE (mean ± standard deviation) 21 ± 12 days after AMI to evaluate myocardial viability. Revascularization of the IR was performed in 54 patients by angioplasty (n = 43) or bypass grafting (n = 11). Coronary angiography and LV cineangiography were repeated at four months to assess LV function and IR patency. RESULTS Sensitivity and specificity of DSE for predicting myocardial recovery after revascularization were 83% and 82%. In the case of late IR patency, specificity increased to 95%, whereas sensitivity remained unchanged. In the 16 patients with myocardial viability and late IR patency, echocardiographic wall motion score index decreased after revascularization from 1.83 ± 0.15 to 1.36 ± 0.17 (p = 0.0001), and left ventricular ejection fraction (LVEF) increased from 0.52 ± 0.06 to 0.57 ± 0.06 (p = 0.0004), whereas in five patients, reocclusion of the IR prevented improvement of segmental or global LV function despite initially viable myocardium. CONCLUSIONS Dobutamine stress echocardiography is reliable to predict recovery of viable myocardium after revascularization in postinfarction patients. Late reocclusion of the IR may prevent LV recovery and influence the accuracy of DSE.