Exercise capacity in an individual with LVAD explantation without heart transplantation

摘要

PURPOSE: Left ventricular assist devices (LVADs) have become a viable treatment alternative to heart transplantation, in some instances providing for a level of improvement of native heart function to allow for device explantation. The aim of this case study was to describe changes in physical work capacity following 9 months of LVAD support. CLINICAL CASE: The patient described here was diagnosed with idiopathic dilated cardiomyopathy and demonstrated worsening heart failure over a 5-year period with a maximum left ventricular end-diastolic diameter of 8.99 cm and an ejection fraction of 15% to 25%. Upon implantation of an LVAD, central hemodynamic function improved and the device was removed after 9 months of support. Left ventricular diastolic and systolic diameter decreased by 39.8% and more than 30%, respectively. The left atrium decreased by 21.7% and ejection fraction was maintained by the LVAD and stabilized at 20%. Four months postexplantation, a cycle ergometry graded cardiopulmonary exercise test was performed. Exercise began at 0 W and increased 25 W per 3-minute stage. RESULTS: The patient showed improvement in peak aerobic capacity when compared to pre-LVAD cardiopulmonary stress tests. Peak oxygen uptake increased from pre-LVAD measures of 11.8 mL ? kg-1 ? min-1 to 17.0 mL ? kg-1 ? min -1. Time to maximal exertion increased from 5 minutes 27 seconds to 15 minutes. CONCLUSION: Results of this case study indicate that significant improvements in native heart function leading to an increased ability to perform work is possible following a period of mechanical unloading through LVAD support.