Myers J, de Souza e Silva CG, Arena R, et al. - In heart failure cases, mortality and major cardiovascular events are strongly predicted by peak VO ₂ (peak oxygen uptake) expressed as percentage of an age‐predicted standard. Test characteristics slightly superior to the commonly employed Wasserman‐Hansen (WH) equation were exhibited by the FRIEND registry (Fitness Registry and the Importance of Exercise: A National Data Base) equation.

• Recently derived FRIEND equation was compared with the WH ppVO ₂ [peak predicted oxygen uptake] equation to predict outcomes in patients (n= 4055) with heart failure.

• For the FRIEND equation, ppVO ₂ was higher than the WH equation (66±30% vs 58±25%).

• Slightly but significantly higher areas under the receiver operating characteristic curves were generated by the FRIEND equation for mortality (0.74 vs 0.72) and cardiac events (0.70 vs 0.68).

• For each 1‐SD higher ppVO ₂ for the FRIEND and WH equations, mortality was decreased by 18% (hazard ratio, 0.82) and by 17% (hazard ratio, 0.83), respectively.

• For cardiovascular events, the corresponding decreases in risk per 1 SD for the FRIEND and WH equations were 23 and 21%, respectively.