Severe Heart Failure and Treatment with Dapagliflozin Across the Ejection Fraction Spectrum

BACKGROUND:Patients with severe heart failure (HF) experience debilitating clinical symptoms and worse cardiovascular (CV) outcomes with an excess mortality risk. OBJECTIVES:The authors aimed to assess the prevalence, CV outcome risk, and treatment response to the sodium-glucose cotransporter 2 inhibitor (SGLT2i) dapagliflozin among patients with severe HF across the spectrum of left ventricular ejection fraction (LVEF) in DAPA-HF and DELIVER. METHODS:Severe HF was adapted from the ESC (European Society of Cardiology) HFA (Heart Failure Association) definition: NYHA functional class III/IV, evidence of HF with reduced, mildly reduced, or preserved LVEF, HF hospitalization within the previous 12 months, and adverse patient-reported symptom burden (Kansas City Cardiomyopathy Questionnaire-Total Symptoms Score <75). Outcomes and the treatment effect of dapagliflozin were assessed for the primary endpoint of CV death or first worsening HF event by severe HF status. RESULTS:Among 10,948 patients with available data to define severe HF, 730 (6.7%) fulfilled the severe HF definition (296/4,722 [6.2%] with LVEF ≤40%, 192/2,101 [9.1%] with LVEF 41%-49%, and 232/4,125 [5.6%] with LVEF ≥50%). Over a median follow-up of 22 months, the primary endpoint occurred in 231 patients, at a rate of 20 per 100 patient-years (Q1-Q3: 17-23 per 100 patient-years). Patients with severe HF experienced a higher rate of events than patients without severe HF (adjusted HR: 1.85; 95% CI: 1.60-2.12), regardless of LVEF (Pinteraction = 0.98). Treatment with dapagliflozin was consistently beneficial in reducing the risk of the primary endpoint regardless of severe HF status (Pinteraction = 0.48) across the LVEF spectrum (3-way Pinteraction = 0.52). The safety profile of dapagliflozin was also consistent regardless of the severe HF status. CONCLUSIONS:Severe HF was associated with an excess risk of CV events across the spectrum of LVEF. Treatment with the SGLT2i dapagliflozin appeared to be safe and effective in reducing the risk of CV death or worsening HF in this population. (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure [DAPA-HF]; NCT03036124; Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure [DELIVER]; NCT03619213).