Left ventricular thrombus (LVT) is a serious post myocardial infarction complication which increases length of hospital stay and cost of hospitalization but above all, leads to severe consequences when responsible for systemic embolization or cerebral stroke (up to 15% of patients with LVT).

Evaluate the prevalence of LVT after ST-segment elevated myocardial infarction (STEMI) by trans thoracic echocardiography (TTE) and cardiac magnetic resonnance (CMR), identify risk factors and better screening strategy.

In all, 330 patients were included in three prospective studies requiring TTE and CMR in the aftermath of a STEMI. 136 patients finally underwent both of these exams.

In all, 12 LVT were detected (8.8% of post STEMI patients) including 5 only by CMR and one only by TTE.

With an univariate analysis, we observed more LVT in patients with a left anterior descending (LAD) involved (100% vs. 46%; P<0.001), EKG anterior STEMI (100% vs. 47%; P<0.001), lower left ventricular ejection fraction (LVEF) at baseline (35% vs. 46%; P<0.001) and after revascularization (45% vs. 52%; P<0.001), LV aneurysm (42% vs. 2%; P<0.001), anterior akinesia (75% vs. 20%; P<0.001), apical akinesia (92% vs. 31%; P<0.001), higher indexed LV end-diastolic and end- systolic volumes (65 vs. 55ml/m²; P=0.04, 38 vs. 27mL/m² P<0.01), lower left ventricular outflow tract velocity time integral (LVOT VTI) (17 vs. 19cm/s; P<0.01) and global longitudinal strain (−10 vs. −14%; P=0.02), fever (33% vs. 12% P=0.04), lower creatinine level (65 vs. 76μmol/L; P=0.04), higher glomerular filtration rate (110 vs. 95ml/min/m²; P=0.01) and Creatin Kinase peak (5773 vs. 2776UI/L; P<0.001) (Fig. 1).

LVT remains common after STEMI, even more in certain subgroups of patients like anteriors ones, those with altered LVEF and/or dilated LV.

CMR allows better diagnosis than TTE, but, because of its availability, the nature of the examinations to carry out and their timing remains to be defined.