Improvement in Peak Oxygen Uptake During First Year of Mechanical Circulatory Support in End-Stage Heart Failure Patients - Follow Up on PRO-VAD Study

Purpose

Published data from PRO-VAD study showed that peak oxygen uptake (pVO2) measured few months after left ventricle assist device (LVAD) implantation is of prognostic value in a similar way as it is in heart failure patients not supported by mechanical circulatory support (MCS). However the data on longitudinal changes of pVO2 in LVAD patients are scarce. We aimed to study these changes in PRO-VAD study population.
Methods

We collected data of serial cardiopulmonary exercise tests (CPET) in adult LVAD recipients in a retrospective, multicenter study. All patients who had their index CPET between 80-210 days from implantation and control CPET within 400 days but not earlier than 90 days from index CPET were included.
Results

Data from 153 patients were included in analysis. The mean age was 52±13 years, 68 % were male and the mean body mass index (BMI) at implantation was 25 ± 4 kg/m2. The majority (68%) had heart failure due to non-ischemic cardiomyopathy and 89% received LVAD as bridge to transplant or decision. The index CPET was performed at median of 183 days and the second CPET at median of 367 days after LVAD implantation, with the median of 182 days between tests. The mean pVO2 at the index CPET was 15,4 ± 4,7 ml/kg/min (51,7 ± 11,9 % of predicted value) and improved significantly to 15,8 ± 4.9 ml/kg/min (pConclusion

Exercise capacity measured by pVO2 increased significantly within first year of LVAD support in PRO-VAD population, with 43 % of patients showing clinically important improvement. The increase was correlated to changes in hemoglobin and independent of heart failure etiology or type of LVAD implanted. With LVAD therapy being increasingly used for long-term support, further research is needed to identify the factors influencing pVO2, in order to further optimize the exercise capacity and prognosis in this patients population.