Noninvasive Ventilation Before Maximum Exercise Test Increases Exercise Tolerance in Subjects With Heart Failure: A Crossover Study.

OBJECTIVE: To evaluate the effect of noninvasive ventilation (NIV) on exercise performance in individuals with heart failure (HF).

DESIGN: Crossover, blind, randomized controlled trial with allocation concealment.

SETTING: University-based research laboratory.

PARTICIPANTS: Participants (N=24) with New York Heart Association class II and III left heart failure and with a mean age of 51.8±10.2 years (women: n=8; men: n=16).

INTERVENTIONS: Ventilatory support attached to the face of the individual via a facemask prior to cardiopulmonary exercise test (CPET) was administered at 2 pressure levels for 30 minutes. Inspiratory pressure of 15cmH2 O and expiratory pressure of 5cmH2 O were applied.

MAIN OUTCOME MEASURES: Maximal oxygen uptake, maximum heart rate, variation between the initial and maximum heart rates, CPET duration, and recovery time oxygen consumption.

RESULTS: Differences were observed in maximal oxygen consumption (nonintervention phase: 18.3±4.4mL·kg-1 ·min-1 vs NIV phase: 20.6±4.9mL·kg-1 ·min-1 , P=.01), heart rate (nonintervention phase: 127.3±20.9 beats per minute vs NIV phase: 134.7±19.5 beats per minute, P=.04), and heart rate variation (nonintervention phase: 63.3%±19.3% vs NIV phase: 69.7%±16.6%, P=.02). Moreover, differences in cardiopulmonary exercise time (nonintervention phase: 7.4±1.5min vs NIV phase: 8.3±1.7min, P=.01) and oxygen consumption recovery time (nonintervention phase: 2.8±1.0min vs NIV phase: 2.4±0.8min, P=.01) were observed.

CONCLUSIONS: NIV elicited beneficial effects in the HF population that included increased exercise tolerance, recovery time optimization, and improved chronotropic and respiratory reserves.