Incidence of Left Ventricular Thrombus in Patients with Acute ST Segment Elevation Myocardial Infarction Treated with Percutaneous Coronary Intervention

Previous studies using two-dimensional non-contrast echocardiography have reported a post-ST segment elevation myocardial infarction (STEMI) left ventricular (LV) thrombus incidence of 3% to 24%. However, these studies were not performed with ultrasound contrast agents (UCAs), which improve accuracy in the diagnosis of LV thrombus. We aimed to determine the early incidence and clinical correlates of LV thrombus in a large consecutive cohort of patients with STEMI. This study included consecutive patients admitted to Saint Luke's Mid America Heart Institute (MAHI) with STEMI who also underwent early percutaneous coronary intervention (PCI) and an echocardiogram. A total of 1698 patients (1205 men, mean age 61±13 years) comprised the study group. Echocardiography was performed on hospital day 2, and a UCA was used in 1292 (76%) patients. LV thrombus was identified in 28 (1.6%) patients. A multivariable logistic regression model showed LAD intervention was independently associated with LV thrombus (odds ratio=7.58, 95% CI {2.20, 26.19} p=0.001), TIMI III flow was marginally associated with less LV thrombus (odds ratio=0.41, 95% CI {0.16, 1.04} p=0.060) and higher LVEF was associated with less LV thrombus (odds ratio=0.96, 95% CI {0.91, 0.97}, p<0.001). In conclusion, LV thrombus was identified in only 1.6% of patients in a large STEMI cohort, significantly lower than previous studies. A UCA was used in most echocardiograms, and it improves accuracy in the detection and exclusion of LV thrombus.