Types and outcomes of cardioversion in patients admitted to hospital for atrial fibrillation: results of the German RHYTHM-AF Study.

Background: Atrial fibrillation (AF) accounts for approximately one-third of hospitalizations for cardiac rhythm disturbances. Little is known about the characteristics of current use of cardioversion (CV) and its success rates in clinical practice in Germany.
Methods: As part of the international RHYTHM-AF Study, 655 consecutive patients with documented AF (mean age 68.3 ± 10.5 years, 64.9 % males) who were considered candidates for CV were prospectively enrolled in 22 German hospitals (21 academic/teaching and 1 non-teaching). CV was considered successful if sinus rhythm or atrial rhythm was obtained within 1 day after start of pharmacological CV (PCV) or if sinus rhythm was achieved and maintained for at least 10 min after electrical CV (ECV).
Results: Patients with AF considered for CV had ECG in 94.4 %, Holter ECG in 25.8 %, and transesophageal echocardiography (TEE) in 73.1 % of cases. They underwent ECV (after mean 16 h, range 4-48), in 65.3 % and PCV in 6.7 % of patients (amiodarone in 47.7 %, flecainide in 27.3 %, propafenone in 2.3 %) as first CV procedure. No CV was performed in 27.9 %, mainly due to spontaneous CV or pathologic TEE. Primary success rates were 86.7 % for electrical CV and 54.5 % for pharmacological CV. More patients in the ECV group compared to the PCV group received oral anticoagulation at discharge (79.2 vs. 59.1 %, p < 0.001), and at 60 days (77.5 vs. 56.8 %, p < 0.001). Further, at 60 days the proportion of patients in sinus rhythm was not different between groups (ECV 76.8 % vs. PCV 77.3 %).
Conclusions: In large academic centres in Germany, the preferred CV method is electrical, mainly due to its easy access and to its higher success rate for the initial restoration of sinus rhythm. Considering the limitations of the open-label, non-randomised study design, overall short-term success rates appeared higher after ECV compared to PCV during hospitalisation, but not after 60 days.