Spontaneous morphologic changes in left ventricular thrombi: a prospective two-dimensional echocardiographic study.

Previous retrospective echocardiographic studies have reported a higher embolic potential of left ventricular thrombi with protruding configuration and patterns of mobility. The present study was performed to prospectively assess the shape and mobility patterns of left ventricular thrombi and their spontaneous changes with time. Two-dimensional echocardiograms were obtained in 109 consecutive patients with acute anterior myocardial infarction within 24 hr of the onset of symptoms, every 24 hr until day 5, every 48 hr until day 15, and then every month for a follow-up of 1 to 29 (mean 14 +/- 8) months in the survivors. None of the patients were treated with anticoagulants or platelet inhibitors during the study period. Left ventricular thrombi, detected in 59 patients (54%), appeared from 1 to 362 (mean 12 +/- 47) days after myocardial infarction. At first detection, the shape was mural in 21 patients and protruding in 38; patterns of mobility were present in eight patients. During follow-up, changes in the shape of the thrombi were noted in 24 patients (41%; from mural to protruding in nine, from protruding to mural in 15). These variations were encountered between 2 and 490 (mean 64 +/- 117) days after the first observation of the thrombus. Patterns of mobility, previously detected in eight patients, disappeared in five of eight within 2 to 28 (mean 14 +/- 11) days.(ABSTRACT TRUNCATED AT 250 WORDS)