Canadian Journal of Cardiology

Baseline Functional Class and Therapeutic Efficacy of Common Heart Failure Interventions: A Systematic Review and Meta-analysis

Published:January 07, 2015DOI:



      New York Heart Association (NYHA) functional class provides important prognostic information and is often used to select patients for cardiovascular therapies, yet, the effect of NYHA class on therapeutic efficacy has not been systematically studied.


      In this systematic review and meta-analysis we compared the relative and absolute mortality benefit of 5 common heart failure interventions (angiotensin-converting enzyme [ACE] inhibitors, β-blockers, mineralocorticoid receptor antagonists [MRAs], implantable cardioverter defibrillator [ICD], and cardiac resynchronization therapy [CRT]) across NYHA class. We included 26 randomized clinical trials of these interventions that reported all-cause mortality stratified according to baseline NYHA class in 36,406 patients.


      Pooled relative risk for NYHA I/II vs III/IV strata were similar for ACE inhibitors (0.90 vs 0.88), β-blockers (0.72 vs 0.79), MRA (0.79 vs 0.75), and CRT (0.80 vs 0.80), with all heterogeneity P > 0.8. Conversely, ICD efficacy was greater for class I/II (relative risk, 0.65 vs 0.86, heterogeneity P = 0.02). The pooled absolute risk difference was smaller for NYHA I/II vs III/IV with ACE inhibitors (−0.02 vs −0.06, P = 0.12), β-blockers (−0.02 vs −0.05, P = 0.047), MRA (−0.03 vs −0.11, P = 0.001), and CRT (−0.01 vs −0.04, P = 0.036), but was similar across NYHA class for the ICD (−0.07 vs −0.05; P = 0.27).


      Relative mortality reductions with most interventions were independent of baseline NYHA class. However, ICD efficacy was greater with NYHA I/II vs III/IV limitation, and absolute benefit was greater with higher NYHA class. For interventions other than the ICD, there is little evidence supporting use of NYHA class as a rigid criterion for selecting heart failure therapies.



      La classification fonctionnelle de la New York Heart Association (NYHA) fournit des informations importantes pour évaluer le pronostic et est souvent utilisée pour sélectionner les patients en vue de traitements cardiovasculaires. Cependant, les répercussions de la classification de la NYHA sur l’efficacité thérapeutique n’ont pas fait l’objet d’études systématiques.


      Au cours de la revue systématique et de la méta-analyse, nous avons comparé les avantages sur la mortalité relative et absolue de 5 interventions habituelles pour le traitement de l’insuffisance cardiaque (inhibiteurs de l’enzyme de conversion de l’angiotensine [ECA], β-bloqueurs, antagonistes du récepteur minéralocorticoïde [ARM], défibrillateur cardioverteur implantable [DCI] et thérapie de resynchronisation cardiaque [TRC]) de toutes les classes de la NYHA. Nous avons inclus 26 essais cliniques aléatoires concernant ces interventions qui rapportaient la mortalité toutes causes confondues stratifiée selon la classification initiale de la NYHA de 36 406 patients.


      Le risque relatif global de la strate I/II de la NYHA vs la strate III/IV était similaire pour les inhibiteurs de l’ECA (0,90 vs 0,88), β-bloqueurs (0,72 vs 0,79), ARM (0,79 vs 0,75) et TRC (0,80 vs 0,80), toute hétérogénéité P > 0,8. En contrepartie, l’efficacité du DCI était plus grande pour la classe I/II (risque relatif, 0,65 vs 0,86, hétérogénéité P = 0,02). La différence du risque absolu global était plus petite pour la classe I/II de la NYHA vs la classe III/IV avec les inhibiteurs de l'ECA (−0,02 vs −0,06, P = 0,12), les β-bloqueurs (−0,02 vs −0,05, P = 0,047), les ARM (−0,03 vs −0,11, P = 0,001) et la TRC (−0,01 vs −0,04, P = 0,036), mais était similaire dans toutes les classes de la NYHA avec le DCI (−0,07 vs −0,05; P = 0,27).


      Les réductions relatives de la mortalité liée à la plupart des interventions étaient indépendantes de la classification initiale de la NYHA. Cependant, le DCI a montré une plus grande efficacité à la classe I/II de la NYHA vs la classe III/IV, et un avantage absolu plus grand avec les classes supérieures de la NYHA. En ce qui concerne les interventions autres que le DCI, peu de données probantes soutenant l’utilisation de la classification NYHA comme critère de sélection rigoureux des traitements de l’insuffisance cardiaque existent.
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