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 (V) over dotO(2), 925 vs. 1,351 L/min; P<0.0001; (V) over dotE/(V) over dotCO(2) 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 (V)over dotO(2), serum Na+ and the use of beta-blockers in patients aged >= 70 years, and LVEF, eGFR and peak (V) over dotO(2) in younger subjects. The MECKI risk score increased across age subgroups, 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.