INCIDENCE AND NATURAL-HISTORY OF LEFT-VENTRICULAR THROMBUS FOLLOWING ANTERIOR WALL ACUTE MYOCARDIAL-INFARCTION

Previous studies have reported left ventricular (LV) thrombus in 20% t o 56% of patients after anterior wall acute myocardial infarction (AMI ). The Healing and Early Afterload Reducing Therapy (HEART) study was a prospective study comparing effects of early (24 hours) or delayed ( 14 days) initiation of ramipril, an angiotensin-converting enzyme inhi bitor, on LV function after anterior wall AMI. This ancillary study as sessed prevalence of LV thrombus. Two-dimensional echocardiography was performed on days 1, 14, and 90 after myocardial infarction. The coho rt consisted of 309 patients. Q-wave anterior wall AMI occurred in 78% ; 87% received reperfusion therapy. The prevalence of LV thrombus was 2 of 309 (0.6%) at day 1, 11 of 295 (3.7%) at day 14, and 7 of 283 (2. 5%) at day 90. One patient had thrombus at 2 examinations. The day 1 e chocardiogram was not correlated with thrombus development. LV size in creased more in patients with thrombus than in those without thrombus. Patients with thrombus had more wall motion abnormality after day 1 t han patients without thrombus (p = 0.03). Thus, the current prevalence of LV thrombus in anterior wall AMI is lower than previously reported , possibly due to changes in AMI management. Preservation LV function is likely to be an important mechanism. Most thrombi are seen by 2 wee ks after AMI. Resolution documented by echocardiography is frequent. ( C) 1997 by Excerpta Medica, Inc.