Exercise performance is a prognostic indicator in elderly patients with chronic heart failure: application of metabolic exercise cardiac kidney indexes score

Background:In patients with chronic heart failure (HF) the Metabolic Exercise Cardiac Kidney Indexes (MECKI) score, is a predictor of cardiovascular death and urgent heart transplantation. We investigated the relationship between age, exercise tolerance and the prognostic value of the MECKI score. Methods and Results: We analyzed data from 3,794 patients with chronic systolic HF. The primary endpoint was a composite of cardiovascular death and urgent heart transplantation. Older patients had higher prevalence of comorbidities and lower exercise performance compared with younger subjects (peak VO2, 925 vs. 1,351 L/min; P<0.0001; VE/VCO2 slope, 33.2 vs. 28.3; P>0.0001). The rate of the primary endpoint was 19% in the highest age quartile and 14% in the lowest quartile. At multivariable analysis, the independent predictors of the primary endpoint were left ventricular ejection fraction (LVEF), eGFR, peak VO2, serum Na+ and the use of β-blockers in patients aged ≥70 years, and LVEF, eGFR and peak VO2 in younger subjects. The MECKI risk score increased across age sub-groups, but on receiver operating characteristic curve analysis its prognostic power was similar in both patients aged ≥ 70 and <70 years. Conclusions:Older patients with HF are a high-risk population with lower exercise performance. The MECKI score increased according to age and maintained its prognostic value also in older patients.