Prognostic role of β-blocker selectivity and dosage regimens in heart failure patients. Insights from the MECKI score database

Aims: The use of β-blockers represents a milestone in the treatment of heart failure with reduced ejection fraction (HFrEF). Few studies have compared β-blockers in HFrEF, and there is little data on the effects of different doses. The present study aimed to investigate in a large database of HFrEF patients (MECKI score database) the association of β-blocker treatment with a composite outcome of cardiovascular death, urgent heart transplantation or left ventricular assist device implantation, addressing the role of β-selectivity and dosage regimens. Methods and results: In 5242 HFrEF patients, we investigated the role of: (i) β-blocker treatment vs. non-β-blocker treatment, (ii) β1-/β2-receptor-blockers vs. β1-selective blockers, and (iii) daily β-blocker dose. Patients were followed for 3.58 years, and 1101 events (18.3%) were observed; 4435 patients (86.8%) were on β-blockers, while 807 (13.2%) were not. At 5 years, β-blocker-patients showed a better outcome than non-β-blocker-subjects [hazard ratio (HR) 0.48, P < 0.0001], while also considering potential confounders. A comparable prognosis was observed at 5 years in the β1-/β2-receptor-blocker (n = 2219) vs. β1-selective group (n = 2216) (HR 0.95, P = ns). A better prognosis was observed in high-dose (>2 5 mg carvedilol equivalent daily dose, n = 1005) patients than in both medium dose (12.5–25 mg, n = 1431) and low dose (<12.5 mg, n = 1960) (HR 1.97, P < 0.001; HR 1.95, P = 0.001, respectively), with no differences between the last two groups (HR 0.84, P = ns). Conclusion: In a large population of chronic HFrEF patients, β-blockers were associated with a more favourable prognosis without any difference between β1- and β2-receptor-blockers vs. β1-selective blockers. A better outcome was observed in subjects receiving a high daily dose.