Transhepatic echocardiography: a novel approach for imaging in left ventricle assist device patients with difficult acoustic windows

AIMS: A significant proportion of left ventricle assist device (LVAD) patients have very difficult transthoracic echocardiographic images. The aim of this study was to find an echocardiographic window which would provide better visualization of the heart in LVAD patients with limited acoustic windows. METHODS AND RESULTS: Based on the anatomic relationships in LVAD patients, a right intercostal transhepatic approach was proposed. By using a computer simulator, we searched for the appropriate probe orientation. Further, 15 ambulatory LVAD patients (age 56 ± 15 years, 73% males) underwent two echocardiographic studies: one normal transthoracic echocardiography following the institutional protocol (Echo 1) and a second study which included the transhepatic approach (Echo 2). The two exams were performed by two different sonographers and the results validated by a third observer for agreement. The transhepatic intercostal window was feasible in all patients, with an image quality allowing good visualization of structures in 93%. Precise quantification of the left ventricular (LV) and right ventricular (RV) function was achieved more often in the Echo 2 (10 vs. 3 patients for LV, P = 0.03 and 14 vs. 8 patients for RV, P = 0.04). A significant difference existed also in the quantification of the LVAD inflow cannula flow by pulsed Doppler (11 patients in Echo 2 vs. 3 patients in Echo 1, P = 0.009). CONCLUSION: This is the first study describing a new echocardiographic window in LVAD patients. The transhepatic window may provide better quantification of left and RV dimensions and function and improvement in Doppler interrogation of the inflow cannula.