Aerobic Capacity (V̇O2peak) In Congenital Heart Disease Versus Heart Failure: Prognostic Implications

Abstract

Introduction VO2peak (peak oxygen consumption) during cardiopulmonary exercise testing is a key prognostic test in patients with non-congenital heart failure (HF). It helps physicians decide which HF patients would derive the greatest survival benefit from cardiac transplant. The predictive value of VO2peak in patients with congenital heart disease on outcomes is not as clear. Hypotheses 1) VO2peak will predict event-free survival in patients with congenital cardiac disease; 2) Patients with congenital heart disease will have longer event-free survival for the primary outcome of death, heart transplant, or LVAD placement compared to patients with heart failure with reduced ejection fraction (HFrEF) even after adjustment for VO2peak. Methods Patients were from a registry of cardiac patients who completed an exercise test in the VO2 Laboratory at Washington University School of Medicine between May 1993 and October 2012. Patients with HFrEF (left ventricular ejection fraction Results A total of 276 patients (138 congenital, 138 HFrEF) were included. Mean (±SD) age was 33.9 ± 11.7y in the congenital group and 40.3 ± 9.7 in the HFrEF group (p=0.00001). Women made up 44.9% of each sample. VO2peak was 21.56 ± 7.15 ml•kg−1•min−1 in the congenital group and 15.99 ± 5.95 ml•kg−1•min−1 in the HFrEF group (p Conclusions A congenital cardiac diagnosis portends longer event-free survival compared to patients with non-congenital HFrEF. Further studies are warranted to investigate if peak VO2 can be used to guide timing for cardiac transplant in the congenital cardiac population.