Cardiopulmonary exercise measures of men and women with HFrEF differ in their relationship to prognosis: The Henry Ford Hospital Cardiopulmonary Exercise Testing (FIT-CPX) project

Abstract Background This study evaluated if different prognostic characteristics exist for peak oxygen consumption (VO 2 ), percent predicted peak VO 2 (ppVO 2 ), and the slope of the change in minute ventilation to volume of carbon dioxide produced (V E -VCO 2 ) slope between men and women with heart failure and reduced ejection fraction (HFrEF). Methods Analysis of the Henry Ford Hospital Cardiopulmonary Exercise Testing database (n = 1085; 33% women, 55% black) of individuals with HFrEF who completed a physician-referred cardiopulmonary exercise testing (CPX) between 1997 and 2010. Primary outcome was a composite of all-cause death, left ventricular assist device placement, and orthotopic heart transplant . Logistic and Cox regressions were performed and Kaplan-Meier survival curves were developed to describe relationships of the CPX variables and the composite outcome within and between men and women. Results All patients were followed-up for a minimum of 5 years, during which there were 643 combined events (62%; 499 deaths, 64 left ventricular assist device implants, 80 orthotopic heart transplant). Each CPX variable was significantly related to event-free survival among both men and women. Log-rank assessment of Kaplan-Meier curves noted survival differences for peak VO 2 and V E -VCO 2 slope (p ≤ .002), but not ppVO 2 ( P = .32), between men and women. Conclusions Prognostic values for peak VO 2 and the V E -VCO 2 slope might be considered separately for men and women, whereas the ppVO 2 value corresponding to 1- and 3-year survival rates may not be different between the sexes.