Low Prevalence of Left Ventricular Thrombus in Patients Undergoing Ventricular Assist Device Evaluation

Abstract

International mechanical circulatory support guidelines recommend pre-operative screening for intracardiac thrombus prior to placement of a left ventricular assist device (LVAD). No data exists on the prevalence of left ventricular (LV) thrombus in advanced heart failure patients referred for LVAD evaluation. LV thrombus has a high prevalence in patients with advanced heart failure undergoing evaluation for LVAD. A retrospective chart review of all patients with advanced heart failure referred for LVAD evaluation at a tertiary care center from 7/2007 to 11/2013 was performed. All patients underwent a contrast transthoracic echocardiogram to evaluate specifically for LV thrombus as part of a standardized LVAD evaluation. A standardized LVAD evaluation was performed on 172 patients with advanced heart failure. Mean age was 51.2 +/- 13.4 years and 66% of patients were male. Ischemic cardiomyopathy was the etiology of the heart failure in 28% of patients. Mean ejection fraction was 11.4 +/- 4.6% and 41% of patients had a history of atrial fibrillation. Contrast echocardiogram during pre-operative screening visualized LV thrombus in 8 patients (4.6%). Of these 8 patients, 4 died without implantation of an LVAD. Follow-up contrast echocardiogram revealed resolution on the LV thrombus in 2 patients who subsequently underwent LVAD implantation. In these patients, no LV thrombus was identified by the surgeon at the time of implant. LV thrombus is infrequently encountered in advanced heart failure patients undergoing LVAD evaluation. Because of the uncommon occurrence of LV thrombus, routine performance of a pre-operative contrast echocardiogram may not be necessary.