Association of plasma BNP levels at different times with cardioversion success, maintenance of sinus rhythm and severity of diastolic dysfunction in patients with atrial fibrillation.

Objective: Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia in adults worldwide, exerting a substantial impact on health, society and healthcare economics. Despite the current management strategies involving direct-current cardioversion (DCCV) and antiarrhythmic drug therapy, recurrence of AF remains a significant challenge. Brain natriuretic peptide (BNP), a crucial neurohormone, has been associated with AF recurrence; however, existing studies have yielded inconclusive results. Diastolic dysfunction, assessed using echocardiography, has also been implicated in AF recurrence. This study aimed to clarify the relationship between BNP levels, echocardiographic parameters and cardioversion success in patients with persistent AF.

Methods: This prospective, observational study enrolled 31 patients with persistent AF. Transthoracic (TTE) and transoesophageal echocardiography, alongside BNP measurements, were performed at various intervals: before cardioversion, 30 minutes post cardioversion and during a One-month follow up. Electrocardiography and TTE were conducted at the one-month mark, categorising patients based on diastolic dysfunction.

Results: Of the 31 patients, 28 successfully converted to sinus rhythm after DCCV. Baseline BNP levels correlated with heart rate and peak E/Em ratio. Patients with early AF recurrence had higher 30-minute BNP levels. Basal BNP levels were not found to be useful in predicting early AF recurrence, whereas BNPlevels at the 30th minute after cardioversion were significantly higher in the group with AF recurrence (318 ± 39.7 vs 153 ± 11.9 pg/ml; p = 0.05). Patients with or without mild diastolic dysfunction showed significantly lower BNP levels than those with moderate-to-severe dysfunction.

Conclusion: The study concluded that BNP levels, measured 30 minutes after DCCV, were more indicative of maintaining sinus rhythm than baseline levels. The correlation between baseline BNP and diastolic dysfunction parameters suggests a potential combined assessment for guiding rhythm-control strategies in patients with AF.