Influence of exertional oscillatory ventilation on exercise performance in heart failure.
BACKGROUND
Exertional oscillatory ventilation (EOV) in heart failure may potentiate the negative effects of low cardiac output and high ventilation on exercise performance. We hypothesized that the presence of EOV might, per se, influence exercise capacity as evaluated by maximal cardiopulmonary exercise test.


RESULTS
We identified 78 severe chronic heart failure patient pairs with and without EOV. Patients were matched for sex, age and peak oxygen consumption (VO2). Patients with EOV showed, for the same peak VO2, a lower workload (WL) at peak (DeltaWatts=5.8+/-23.0, P=0.027), a less efficient ventilation (higher VE/VCO2 slope: 38.0+/-8.3 vs. 32.8+/-6.3, P<0.001), lower peak exercise tidal volume (1.49+/-0.36 L vs. 1.61+/-0.46 L, P=0.015) and higher peak respiratory rate (34+/-7/min vs. 31+/-6/min, P=0.002). In 33 patients, EOV disappeared during exercise, whereas in 45 patients EOV persisted. Fifty percent of EOV disappearing patients had an increase in the VO2/WL relationship after EOV regression, consistent with a more efficient oxygen delivery to muscles. No cardiopulmonary exercise test parameter was associated with the different behaviour of VO2/WL.


CONCLUSIONS
The presence of EOV negatively influences exercise performance of chronic heart failure patients likely because of an increased cost of breathing. EOV disappearance during exercise is associated with a more efficient oxygen delivery in several cases.
Schmid
Jean-Paul
JP
Centro Cardiologico Monzino, IRCCS, Institute of Cardiology, University of Milan, Milan, Italy.
Apostolo
Anna
A
Antonioli
Laura
L
Cattadori
Gaia
G
Zurek
Marzena
M
Contini
Mauro
M
Agostoni
Piergiuseppe
P
D000368:Aged; D002908:Chronic Disease; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012123:Pulmonary Ventilation; D015656:Respiratory Mechanics; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013557:Switzerland; D013990:Tidal Volume; D014481:United States; D014939:Work of Breathing