Cardiac computed tomography for prediction of myocardial viability after reperfused acute myocardial infarction

Background: Perfusion defects (PDs) detected with cardiac magnetic resonance (CMR) imaging predict the functional recovery of myocardial function after acute myocardial infarction. Objective: We evaluated the ability of cardiac computed tomography (CCT) to predict the recovery of regional left ventricular (LV) systolic function after ST elevation myocardial infarction (STEMI). Methods: Seventeen patients (mean age, 60 ± 10 years) presenting with STEMI were prospectively studied. Each patient underwent CCT and CMR at baseline and after an average of 6 months. Areas of PD were quantified. Segmental LV systolic function was semiquantitatively assessed by CMR. An improvement at 6 months by ≥1 category in the regional wall motion score was considered LV recovery. Results: Coronary artery revascularization was successfully performed with postprocedural TIMI 3 flow in 16 cases. On CCT assessment, 107 of 289 segments (37%) had some degree of PD. On follow-up, segments with <25% PD at baseline had no worsening of wall motion. In segments with >75% PD, 89% (9 of 11) showed akinesis or worsening of wall motion. The odds ratio for improvement in segmental wall motion with increasing PD category was 0.63 (95% CI, 0.42-0.97; P = 0.035). The degree of PD on CT predicted LV recovery at follow-up (P < 0.0001). Conclusions: The transmural extent of myocardial infarction as detected and quantified with CCT predicts the recovery of regional systolic LV function after revascularization for acute STEMI.