Abstract 16042: Echocardiography Ramp Test in Continuous-Flow Left Ventricular Assist Devices and Aortic Regurgitation: Do Loading Conditions Matter?
INTRODUCTION: An echocardiographic ramp speed test (RST) is a novel approach to evaluate suspected device obstruction after continuous-flow left ventricular assist device (CF-LVAD) implant. Failure to reduce the left ventricular end diastolic dimension (LVEDD) with increasing CF-LVAD speeds has been shown to be highly predictive of pump obstruction. However, the presence of aortic regurgitation (AI) in patients with CF-LVAD imposes an increase on loading conditions that could alter the predictive power of RST.
Hypotheses: In the presence of at least mild to moderate AI and no evidence of device obstruction, the LVEDD-speed slope is abnormal.
Methods and Results: Ten RSTs were prospectively performed in patients with at least mild to moderate continuous AI (Group I) without clinical suspicion of obstruction and were compared to eighteen patients on CF- LVAD support with no or mild AI and no suspicion of obstruction (Group II). Echocardiography was performed to assess severity of AI and LVEDD. The results of the speed versus LVEDD, pulsatility index (PI) and power (PW) were plotted and linear function slopes were calculated. Eighty percent of the patients with at least mild to moderate AI had a flat LVEDD/speed slope > -0.16. In comparison, all the patients in Group II had a normal LVEDD/speed slope.
CONCLUSION: RST is a useful diagnostic tool for diagnosing CF-LVAD device obstruction, but in the presence of at least mild to moderate AI, increasing pump speed does not lead to effective decompression of the left ventricle and results in an abnormal slope LVEDD/speed slope. Longitudinal studies are needed to clarify the diagnostic role of RST in the setting of increased loading conditions
- © 2013 by American Heart Association, Inc.