CPET as a prognosis assessing tool in patients with heart failure with preserved ejection fraction

Abstract

Abstract Introduction Patients with heart failure with preserved ejection fraction represent half of the heart failure patients nowadays, an at least steady trend due to the aging of the population. We investigated whether the parameters obtained from cardiopulmonary exercise testing (CPET) correlated with the prognosis of these patients. This prospective observational cohort study looks into the relationship between the CPET parameters peak VO2 and VE/VCO2 slope and the heart failure hospitalizations or cardiovascular death of these patients. Methods From August 2016 until May 2019, 99 patients of our outpatient clinic with newly diagnosed with heart failure with preserved ejection fraction underwent cardiopulmonary exercise testing. Median follow-up was 30 months (interquartile range, 24-38.5). We selected peak VO2 <14 ml/min/kg and a VE/VCO2 slope > 34 as threshold values for our primary endpoint, a composite of hospitalization for heart failure or cardiovascular death. Results The mean age was 75.07 ± 7.31 years, 48.5% were women, 24.2% were at NYHA class III and mean NTproBNP was 511 pg/mL. Mean peakVO2 was 15.09 ± 4.75 and mean VE/VCO2 was 36.05 ± 6.60. During follow-up, they were 67 hospitalizations, 53 cardiovascular hospitalizations, 24 heart failure hospitalizations and 4 deaths. Over a median follow-up of 30 months, the primary outcome event occurred in 5 of 40 patients (12.5%) with a VE/VCO2 Slope ≤ 34 and in 19 of 59 patients (32.2%) with a VE/VCO2 Slope > 34 (hazard ratio, 2.688; 95% confidence interval (CI); P 0.04). On multivariate analysis, accounting for heart failure hospitalization or cardiovascular death as a terminal event, VE/VCO2 slope was independently associated with the risk of admission due to heart failure worsening. Conclusion In patients with heart failure with preserved ejection fraction, a VE/VCO2 Slope > 34 predicts heart failure hospitalizations and cardiovascular death.Primary Endpoint