Assessment of exercise capacity in an individual with LVAD explanation without heart transplantation
BACKGROUND: Left Ventricular Assist Device’s (LVAD) have become a viable treatment alternative to heart transplantation. While under LVAD support, some have shown significant recovery of native heart function allowing for the removal of the device. METHODOLOGY: The patient in this study was diagnosed with idiopathic dilated cardiomyopathy and demonstrated worsening heart failure over a five year period with a maximum left ventricular end diastolic diameter of 8.99 cm and an ejection fraction between 20-25%. Upon implantation of a LVAD, the patient’s central hemodynamic function returned to near normal and the device was removed. Four months post explanation a cycle ergometry graded exercise peak VO2 test was performed. Exercise began at 0 Watts and increased 25 Watts per 3 minute stage. 12 lead EKG was used to determine heart function. RESULTS: The patient showed improvement in peak aerobic capacity when compared to pre LVAD cardiopulmonary stress tests. VO2 increased from pre LVAD measures of 11.8ml•kg-1•min-1 to 17.0 ml•kg-1•min-1. Time to maximal exertion increased from 5 minutes 27seconds to 15 minutes. CONCLUSION: The results from this case study indicate that significant improvements in native heart function is possible with a period of mechanical unloading through LVAD support.
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