Cardiac magnetic resonance detection of left ventricular thrombus in acute myocardial infarction.

Introduction: Left ventricular thrombosis (LVT) is a possible complication of acute myocardial infarction. Aim of our study was to evaluate incidence and clinical characteristics of patients with LVT after ST elevation myocardial infarction (STEMI) using contrast- enhanced magnetic resonance (CMR).

Methods and results: In a prospective cohort of 36 consecutive patients with STEMI acutely reperfused with primary percutaneous coronary intervention, CMR was performed within one week. LVT was found in 7 patients (19%), and was located in left ventricle apex or adherent to antero-septum. Compared to the rest of population patients with LVT have lower ejection fraction (38 ± 7% versus 51 ± 6%, P = 0.009), larger left ventricle end systolic volume (95.8 ± 19 ml versus 68.9 ± 19 ml, P = 0.02), higher time to reperfusion (9.3 ± 7.2 versus 5 ± 3.6, P = 0.03) and left anterior descending artery was constantly involved (100% versus 41 %, P = 0.06). In 5 cases the LVT was also detected by echocardiography, however, in 2 cases it was missed.

Conclusions: The incidence of LVT after STEMI is not negligible and was accurately detected by CMR. Localization of myocardial infarction, time to reperfusion, ejection fraction and left ventricle end systolic volume are the most important predictors of left ventricle thrombus formation.