Can History of Myocardial Infarction Reliably Indicate Myocardial Viability in Patients With a Coronary Chronic Total Occlusion and Good Collateral Circulation?

We read with interest the study by Shaikh et al reporting that none of the patients with coronary chronic total occlusions (CTOs) and a prior Q-wave myocardial infarction (MI) in the CTO-supplied territory had viable myocardium even in the presence of good collateral circulation. Based on our large, multicenter registry on CTO in percutaneous coronary intervention, PROGRESS-CTO, we believe viability testing may still be of value in patients with a CTO and a prior MI, especially if their ejection fraction is low and dyspnea is the predominant symptom.