Abstract 14352: Periodic Breathing During Cardiopulmonary Exercise Test is a Cornestone in Risk Stratification of Older Heart Failure Patients
Purpose: the prognostic value of exercise oscillatory breathing (EOB) and enhanced ventilatory response to exercise (EVR) during the cardiopulmonary test (CPX) has been described in young chronic heart failure (CHF) patients but not among elderly CHF patients. The aim of this study was to clarify whether CPX is a useful prognostic tool even in elderly population.
Methods: we prospectively followed-up 370 HF outpatients ≥65 years after a symptom-limited CPX. We tested the predictive value of ventilatory parameters for cardiovascular (CV) mortality and a composite of mortality and HF hospitalizations.
Results: median age was 74 years, 29% were female, 51% had ischemic heart disease, 25% NYHA class III; ejection fraction was 41% [34–50]. Peak oxygen consumption (PVO2) was 11.9 [9.9–14] ml/kg/min, the slope of the regression line relating ventilation to CO2 output, (VE/VCO2 slope) was 33.9 [29.8–39.2]. A VE/VCO2 slope ≥34 (EVR) was found in 50%, EOB in 58% and both in 30.5% of patients. During a median tracking period of 29 [12–47] months, 73 patients died for CV causes and 90 were admitted for worsening HF. Using a time-to-first event approach, overall 157 patients met the combined end-point. By multivariable analysis, EOB was the strongest predictor of both CV mortality and of the combined end point together with an increased VE/VCO2 slope, independently of preserved or reduced systolic function.Survival and HF admission-free survival rates were significantly different according to the presence of neither EOB or EVR (94% and 75%), either one (85% and 57%) or both predictors combined (63% and 46%, respectively). In subjects with both EOB and EVR, the hazard ratio was 8.24 (95% confidence interval (CI ) 3.25–20.8) for CV mortality and 3.085 (95% CI 1.874- 5.079; p < 0.0001) for the combined end point, respectively.
Conclusions: among elderly CHF patients, EOB prevalence is higher than previously reported in middle-aged cohorts. EOB emerged as the strongest ventilatory predictor of outcome prognostically synergic with EVR for the identification of patients at highest risk. These findings prospect the utility of comprehensively assessing CPX-derived information to optimize the clinical and prognostic work up of elderly CHF patients.
- © 2010 by American Heart Association, Inc.