It was unknown if the pattern of atrial fibrillation (AF) or the time of AF treatment affects how well the early rhythm control (ERC) works. For a study, researchers sought to examine patients who presented with various AF patterns and received either conventional treatment or ERC and were compared in terms of clinical features and outcomes.

In the predetermined analysis of the EAST-AFNET 4 (Early treatment of atrial fibrillation for stroke prevention) experiment, the effects of ERC were compared in first-diagnosed atrial fibrillation (FDAF), paroxysmal AF (paroxAF), and persistent AF (persAF). Over the course of a mean follow-up of 5.1 years, associations between AF pattern & main outcomes (first major outcome: cardiovascular mortality, stroke, and hospitalization for heart failure and acute coronary syndrome; second primary outcome: nighttime hospital stays per year) were compared. The EQ-5D was used to evaluate changes in quality of life factors connected to health.

In comparison to patients with paroxAF (n=994, 70 years, 50.0% female), and persAF (n=743, 70 years of age, 38.0% female), FDAF patients (n=1,048, enrolled 7 days after diagnosing AF) were marginally older (71 years, 48.0% female). In each of the 3 AF patterns, ERC decreased the main result. Hospitalizations for acute coronary syndrome were more common in FDAF (incidence rate ratio [IRR]: 1.50; 95% CI: 0.83-2.69; P=0.032) than in paroxAF (IRR: 0.64; 95% CI: 0.32-1.25) or persAF IRR: 0.50; 95% CI: 0.25-1.00). Patients with FDAF stayed in the hospital longer (IRR: 1.38; 95% CI: 1.12-1.70; P=0.004) than patients with paroxAF (IRR: 0.84; 95% CI: 0.67-1.03) and persAF (IRR: 1.02; 95% CI: 0.80-1.30). ERC enhanced patients’ health-related quality of life (EQ-5D score)  in patients with paroxAF and persAF but not in patients with FDAF (P=0.019).

In all AF patterns, ERC lowers the first primary composite result. Particularly on ERC, patients with FDAF are at significant risk for acute coronary syndrome and hospitalization.