Background: After reperfusion therapy for acute myocardial infarction (AMI), evaluation of transmural myocardial microcirculation can indicate prognosis. The aim of the present study was to determine whether the evaluation of transmural myocardial microcirculation by newly developed 4-slice computed tomography (CT) can estimate the recovery of left ventricular function.
Methods and results: Seventeen consecutive patients who had anterior AMI with a total occlusion in the proximal left anterior descending artery (LAD) and who had undergone successful balloon reperfusion therapy within 24 h of the onset of AMI were examined. Four-slice CT was performed 10-14 days after AMI onset. The median of the epicardial perfusion ratio (infarcted anterior epicardial CT number/intact lateral epicardial CT number ratio = 92%) was used to categorize the cases into 2 groups: the transmural infarction group (n=8) and the subendocardial infarction group (n=9). Although no significant difference was observed between myocardial enhancement by CT in the acute phase and anterior wall motion or ejection fraction in the acute phase, the transmural infarction group showed poor recovery of anterior wall motion at 6 months after AMI onset, whereas the subendocardial infarction group exhibited good recovery of regional and global left ventricular function.
Conclusions: Transmural myocardial microcirculation imaged by 4-slice CT can predict wall motion recovery after AMI.