Inducible Ischemia in Asymptomatic Patients With Coronary Chronic Total Occlusions: A Stress CMR Study

Background Given the divergence in recommendations regarding the relevance of inducible ischemia regarding the indication to revascularize chronic total occlusions (CTOs) among European and North American guidelines, we aim at investigating the prevalence and the prognostic impact of significant inducible ischemia in an unselected cohort of asymptomatic CTO patients, integrating collateralization status and viability assessment with stress cardiac magnetic resonance (CMR).Methods From a cohort of 749 patients referred to our center with a diagnosis of CTO, we retrospectively analyzed 111 asymptomatic individuals who underwent an adenosine stress CMR. The amount of inducible ischemia subtended by the CTO was calculated, as well as the presence of viable myocardium and the collateralization status. The decision to revascularize the CTO was based on a multiparametric assessment conducted by the Heart Team, taking into consideration the vessels' anatomy and the amount of inducible ischemia. A composite endpoint of cardiovascular mortality and non-fatal myocardial infarction was considered.Results Thirty-seven patients out of 111 (33%) showed a significant amount of inducible ischemia, indicated by an ischemic burden of at least 10% of the left ventricular (LV) mass. The risk of cardiovascular adverse events was similar among patients who received or not revascularization of the CTO.Conclusions Among asymptomatic patients with CTO undergoing stress CMR, one out of three patients exhibited a substantial amount of inducible ischemia. Considering the possible benefit of revascularization in patients with a significant amount of inducible ischemia, these observations may suggest a possible broader role of stress-CMR within asymptomatic CTO patients.