1412Effect of beta-blocker dose on the prognosis in chronic heart failure patients depending on the presence of atrial fibrillation. Data from FAR NHL (FARmacology and NeuroHumoraL activation) registry
Authors: Labr K , Spinar J , Parenica J , Spinarova L , Malek F , Spinarova M , Ludka O , Jarkovsky J , Benesova K , Labrova R 
Published: October 2019

Abstract

Background
Beta-blockers (BB) decrease morbidity and mortality in heart failure patients and are part of the first line treatment together with inhibitors of angiotensin converting enzyme. New metaanalysis from year 2014 of main BB studies in chronic heart failure showed no benefit of BB in patients with atrial fibrillation (AF).

Methods
1088 at least one month stable chronic heart failure patients with ejection fraction <50% were included in FAR NHL (FARmacology and NeuroHumoraL activation) registry. Three centers with speciality in heart failure in the Czech Republic were participating from November 2014 to December 2015.

Results
80% patients were male with median age 66 years. Aetiology of heart failure was in 49.4% ischemic heart disease, in 42.3% dilated cardiomyopathy, in 0.5% hypertrophy cardiomyopathy. From those receiving beta-blockers 20% received low dose similar to the starting dose, 57% medium dose and 17% high dose which was set as the target BB dose. Nearly 93.8% of patients received BB. But only 17.0% received the high dose of BB. 6.2% of patients were not treated by BB at all. One third of patients (34.5%) had atrial fibrillation in medical history or newly recorded on electrocardiogram. Patients with AF were much older (median 63 vs. 70 years, respectively; p<0.001), had higher heart rate (72 vs. 74 /min; p<0.006) and were also in higher class of NYHA (New York Heart Association; p=0.005).
The primary endpoint was set as all cause death, mechanical circulatory support implantation, orthotopic heart transplantation or hospitalization for acute heart failure. Patients with AF survived without primary endpoint in 70.6%, patients without AF in 78.8% (p=0.005) even after age standardization.
There was significantly different survival according to dose of beta-blocker, the higher was dose of BB, the higher was survival. Patients with no beta-blocker survived without primary endpoint in 63.9%, with low dose survived in 72.6%, medium dose in 77.0% and with high dose in 80.9%. We devided FAR NHL patients into two groups according to atrial fibrillation. Patients without AF had the better survival without primary endpoint. The higher dose of beta-blockers they got, the better survival they had (69.5%, 76.7%, 78.9%, 85.1%; p=0.007). Also patients with AF had better survival without primary endpoint, the higher dose of beta-blocker they got, the higher was their survival without endpoitnt (56.0%, 63.6%, 73.0%, 75.8%; p=0.007).

Conclusion
In FAR NHL registry of stable chronic heart failure patietnts was one third of patients with atrial fibrillation. Nearly 94% of patients received beta-blocker. But only 17% received the target dose. Pacients even with or without atrial fibrillation had the significantly better survival without primary endpoint the higher was the dose of beta-blocker.