Peak oxygen uptake recovery delay after maximal exercise in patients with heart failure

Purpose: Peak oxygen uptake recovery delay (V. o2peakRD), measured as the time until post-exercise oxygen uptake (V.o2) decreases below V.o2peak following maximal cardiopulmonary exercise testing (CPX), has been recognized as an abnormal response, associated with reduced cardiac output reserve during exercise in patients with heart failure (HF). In the current study we examined the association of V.o2peakRD during routine CPX testing of patients with symptomatic HF across a wide range of left ventricular ejection fraction (LVEF) values with clinical biomarkers. Methods: In this retrospective study, 80 clinically stable symptomatic HF patients across a wide range of LVEF at our institution were evaluated that put forth a minimally acceptable effort during CPX testing (respiratory exchange ratio ≥ 1.00). The V.o2peakRD was measured in 10-sec intervals following maximal CPX testing. Markers of elevated cardiac filling pressures (N-terminal pro-brain natriuretic peptide [NTproBNP] and echocardio-Doppler E/e') and other key CPX parameters were explored for their association with V.o2peakRD. Results: The mean V.o2peakRD and V.o2peak were 10 (interquartile range 10, 40) sec and 13.9 (11.6, 16.4) mL.kg−1. min−1, respectively. V.o2peakRD demonstrated a positive linear trend with serum NTproBNP levels and E/e' (TJT= 1239.500, z = 2.634, P <.01; TJT= 1081.000, z =2.046, P =.04, respectively). Conclusion: Prolonged V.o2peakRD following exercise is associated with markers of greater disease severity in patients with HF