Editorial How many patients need cardiac resynchronization therapy?

This editorial refers to ‘How many patients with heart failure are eligible for cardiac resynchronization? Insights from two prospective cohorts ’ by F. McAlister et al., doi:10.1093/eurheartj/ehi446 For patients with moderate or severe heart failure who have evidence of cardiac dyssynchrony there is overwhelming evi-dence that cardiac resynchronization therapy (CRT) improves symptoms substantially, reduces morbidity, and prolongs life.1 The CARE-HF programme demonstrated that CRT reduced all-cause mortality by 40 % and cardiovascular mor-tality by about 45%.2 The COMPANION trial, which was stopped prematurely, and a meta-analysis of CRT trials includ-ing 3393 patients, are consistent with these data.1 In CARE-HF, the absolute reduction in mortality was 13.4%,2 which trans-lates into a life saved for every 7.5 devices implanted ove