0129: Left ventricular thrombus among patients with anterior myocardial infarction and low ejection fraction: incidence, diagnostic methods and evolution. A prospective multicenter study

Introduction LV thrombi complicate 5-10% of unselected anterior myocardial infarction (Ant-MI).However, the incidence and the evolution of LV thrombi in a high risk population of patients with Ant-MI complicated with LV systolic dysfunction is not well known. Cardiac magnetic resonance imaging with contrast delayed enhancement (CMR-DE) is nowadays considered the gold standard in assessment of LV thrombus but published comparison between transthoracic echocardiography (TTE) and CMR-DE are scarce. Hypothesis We assessed the hypothesis that LV thrombi are still frequent after a large Ant MI, and that a focused TTE has a good accuracy to detect them when compared to CMR-DE. Methods In 7 centers, we prospectively included patients having a left ventricular ejection fraction (LVEF) inferior to 45% at a first TTE performed less than 7 days after an Ant-MI. A second evaluation including TTE and CMR-DE (analyzed by blinded examiners) was performed at 30 days follow up. A third TTE assessment was performed between the sixth and the twelfth months. Results One hundred patients (men: 71%, mean age: 59.1±12.1 years, LVEF: 33.5±6.0 %). were consecutively included 4.8±1.9 days after an Ant-MI. Eighty eight of them (88%) had had a primary coronary angioplasty. Among them, 26 LV thrombi were detected. When compared with CMR-DE, TTEE sensibility and specificity were 94.7% and 98.5% respectively. Twenty four (92.3%) of the LV thrombi disappeared under triple antithrombotic therapy including a vitamin K antagonist added to the classical dual anti-platelet therapy. One patient died from a recurrent subdural haematoma, another one had a peripheric embolism. Conclusions In this prospective multicenter study, despite a dual anti-platelet therapy, LV thrombus occured in 26% of patients after an anterior MI complicated with LV dysfunction. Focused TTE has a high accuracy for their detection.CMR-DE should be performed only in patients in whom the apex is not clearly seen