Echocardiographic Detection of Left Ventricular Thrombus in Patients Undergoing Heartmate II Left Ventricular Assist Device Implantation

PURPOSE: Transthoracic (TTE) and transesophageal echocardiograms (TEE) are considered accurate in detecting the presence of left ventricular (LV) thrombus. A persistent LV thrombus poses risks of pump thrombosis and stroke in LVAD recipients. The relationship between preoperative echocardiography and intraoperative findings at LVAD implantation has not previously been studied. METHODS: A retrospective review examined all patients undergoing LVAD placement or exchange from October 2011 to March 2014. Preoperative TTE and TEE data were validated with presence of LV thrombus during the direct inspection at the time of LVAD placement, and the findings were analyzed quantitatively. RESULTS: Between October 2011 and March 2014, 99 patients underwent a total of 107 LVAD implants. Preoperative TTE was available in 93 (86.9%) cases, while preoperative TEE was available in 37 cases (34.6%). On preoperative TTE, LV thrombus was correctly identified in only two cases, while on preoperative TEE no cases of LV thrombus were identified correctly, and there were 2 false positive reports. Intraoperative inspection revealed presence of LV thrombus in 14 cases. The sensitivity of preoperative TTE was 16.7% and the specificity 100% in detecting LVT, compared to 0% and 93.8%, respectively, for TEE. CONCLUSIONS: Preoperative echocardiogram offers low accuracy for presence of LV thrombus. Overall, the sensitivity is too low to reliably exclude thrombus. This could have significant implications in planning off-pump LVAD exchange as thrombus could be missed. More data are necessary to determine whether this could have significant effects on thromboembolic complications and survival.