Exercise training increases oxygen uptake efficiency slope in chronic heart failure.
OBJECTIVE
The oxygen uptake efficiency slope (OUES) is a novel measure of cardiopulmonary reserve. OUES is measured during an exercise test, but it is independent of the maximally achieved exercise intensity. It has a higher prognostic value in chronic heart failure (CHF) than other exercise test-derived variables such as(Equation is included in full-text article.)or(Equation is included in full-text article.)slope. Exercise training improves(Equation is included in full-text article.)and(Equation is included in full-text article.)in CHF patients. We hypothesized that exercise training also improves OUES.


RESULTS
We studied 34 New York Heart Association (NYHA) class II-III CHF patients who constituted an exercise training group T (N=20; 19 men/1 woman; age 60+/-9 years; left ventricular ejection fraction 34+/-5%) and a control group C (N=14; 13 men/one woman; age 63+/-10 years; left ventricular ejection fraction 34+/-7%). A symptom-limited exercise test was performed at baseline and repeated after 4 weeks (C) or after completion of the training program (T). Exercise training increased NYHA class from 2.6 to 2.0 (P<0.05),(Equation is included in full-text article.)by 14% [P(TvsC)<0.01], and OUES by 19% [P(TvsC)<0.01]. Exercise training decreased(Equation is included in full-text article.)by 14% [P(TvsC)<0.05].


CONCLUSIONS
Exercise training improved NYHA class,(Equation is included in full-text article.)and also OUES. This finding is of great potential interest as OUES is insensitive for peak load. Follow-up studies are needed to demonstrate whether OUES improvements induced by exercise training are associated with improved prognosis.
Gademan
Maaike G J
MG
Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
Swenne
Cees A
CA
Verwey
Harriette F
HF
van de Vooren
Hedde
H
Haest
Joris C W
JC
van Exel
Henk J
HJ
Lucas
Caroline M H B
CM
Cleuren
Ger V J
GV
Schalij
Martin J
MJ
van der Wall
Ernst E
EE
D000368:Aged; D002908:Chronic Disease; D005080:Exercise Test; D005081:Exercise Therapy; D005260:Female; D006333:Heart Failure / Q000378:metabolism / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012123:Pulmonary Ventilation; D012720:Severity of Illness Index; D013318:Stroke Volume; D016896:Treatment Outcome; D016277:Ventricular Function, Left