Prognostic Value of Peak Oxygen Uptake in Patients Supported With Left Ventricular Assist Devices (PRO-VAD)

OBJECTIVES The purpose of this study was to examine whether peak oxygen uptake (pVO2) and other cardiopulmonary exercise test (CPET)-derived variables could predict intermediate-term mortality in stable continuous flow LVAD recipients. BACKGROUND pVO(2) isa cornerstone in the selection of patients for heart transplantation, but the prognostic power of pVO(2) obtained in patients treated with a left ventricular assist device (LVAD) is unknown. METHODS We collected data for pVO(2) and outcomes in adult LVAD recipients in a retrospective, multicenter study and evaluated cutoff values for pVO(2) including: 1) values above or below medians; 2) grouping patients in tertiles; and 3) pVO(2) <= 14 ml/kg/min if the patient was not treated with beta-blockers (BB) or pVO(2) <= 12 ml/kg/min if the patient was taking BB therapy. RESULTS Nine centers contributed data from 450 patients. Patients were 53 +/- 13 years of age; 78% were male; body mass index was 25 +/- 5 kg/m(2) with few comorbidities (stroke: 11%; diabetes: 18%; and peripheral artery disease: 4%). The cause of heart failure (HF) was most often nonischemic (66%). Devices included were the HeartMate II and 3 (Abbott); and Heartware ventricular assist devices Jarvik and Duraheart (Medtronic). The index CPET was performed at a median of 189 days (154-225 days) after LVAD implantation, and mean pVO(2) was 14.1 +/- 5 ml/kg/min (47% +/- 14% of predicted value). Lower pVO(2) values were strongly associated with poorer survival regardless of whether patients were analyzed for absolute pVO(2) in ml/kg/min, pVO(2) <= 12 BB/14 ml/kg/min, or as a percentage of predicted pVO(2) values (P <= 0.001 for all). For patients with pVO(2) >12 BB/14 and ventilation/carbon dioxide relationship (VE/VCO2) slope <35, the 1-year survival was 100%. CONCLUSIONS Even after LVAD implantation, pVO(2) has prognostic value, similar to HF patients not supported by mechanical circulatory support devices. (C) 2021 by the American College of Cardiology Foundation.

Automated summary

This study found that even after LVAD implantation, pVO2 still holds prognostic value and is similar to HF patients not supported by mechanical circulatory support devices. Lower pVO2 values were strongly associated with poorer survival, regardless of the analysis method used.