Article

Oxygen uptake at the anaerobic threshold (VO2AT), a submaximal
exercise-derived variable, independent of patients' motivation, is a marker of
outcome in heart failure (HF). However, previous evidence of VO2AT values
paradoxically higher in HF patients with permanent atrial fibrillation (AF) than
in those with sinus rhythm (SR) raised uncertainties. DESIGN: We tested the
prognostic role of VO2AT in a large cohort of systolic HF patients, focusing on
possible differences between SR and AF. METHODS: Altogether 2976 HF patients
(2578 with SR and 398 with AF) were prospectively followed. Besides a clinical
examination, each patient underwent a maximal cardiopulmonary exercise test
(CPET). RESULTS: The follow-up was analysed for up to 1500 days. Cardiovascular
death or urgent cardiac transplantation occurred in 303 patients (250 (9.6%)
patients with SR and 53 (13.3%) patients with AF, p = 0.023). In the entire
population, multivariate analysis including peak oxygen uptake (VO2) showed a
prognostic capacity (C-index) similar to that obtained including VO2AT (0.76 vs
0.72). Also, left ventricular ejection fraction, ventilation vs carbon dioxide
production slope, beta-blocker and digoxin therapy proved to be significant
prognostic indexes. The receiver-operating characteristic (ROC) curves analysis
showed that the best predictive VO2AT cut-off for the SR group was 11.7
ml/kg/min, while it was 12.8 ml/kg/min for the AF group. CONCLUSIONS: VO2AT, a
submaximal CPET-derived parameter, is reliable for long-term cardiovascular
mortality prognostication in stable systolic HF. However, different VO2AT cut-off
values between SR and AF HF patients should be adopted.
CI - (c) The European Society of Cardiology 2014.

Langue : ANGLAIS