Meta-Analysis on Drug and Device Therapy of New York Heart Association Functional Class IV Heart Failure With Reduced Ejection Fraction

Heart failure with reduced ejection fraction (HFrEF) is associated with significant morbidity and mortality, particularly in patients with New York Heart Association (NYHA) functional class IV symptoms. Decades of discovery have heralded significant advancements in the pharmacologic management of HFrEF. However, patients with NYHA IV symptoms remain an under-represented population in almost every clinical trial to date, leaving clinicians with limited evidence with which to guide drug treatment decisions in this patient group with severe heart failure. Randomized controlled trials of adult patients with NYHA IV symptoms of HFrEF randomized to current guideline-recommended medical therapy were included in this systematic review and meta-analysis. The outcomes of interest included the rate of all-cause mortality, cardiovascular mortality, and heart failure hospitalization. A total of 39 randomized controlled trials were included. A total of 6 studies examined angiotensin converting enzyme inhibitors, with meta-analyses of 2 demonstrating a reduced risk of all-cause mortality (relative risk (RR) 0.76, 95% confidence interval 0.59 to 0.97, p = 0.03). A total of 11 studies examined β blockers, with meta-analysis of 6 demonstrating a reduced risk of all-cause mortality (risk ratio 0.74, 95% confidence interval 0.60 to 0.92, p = 0.008). A study examined the mineralocorticoid antagonist spironolactone, reporting a reduced risk of all-cause mortality in the NYHA IV subgroup. A total of 6 studies examined device therapy, demonstrating the benefit of cardiac resynchronization therapy with or without an implantable cardiac defibrillator in reducing hospitalization in the NYHA IV subgroup. Although trial evidence exists for angiotensin converting enzyme inhibitors, β-blockers, and mineralocorticoid antagonist therapy in the NYHA IV population, the role of angiotensin receptor blockers is unclear. Ivabradine, angiotensin receptor neprilysin inhibitors, and sodium-glucose transport protein 2 inhibitors remain underinvestigated and have not been proved to provide any benefit above standard heart failure therapy in patients with HFrEF and NYHA IV symptoms.