Post-Operative Atrial Fibrillation: Current Treatments and Etiologies for a Persistent Surgical Complication

Abstract

Post-operative atrial fibrillation (POAF) is a persistent and serious surgical complication that occur in 20-55% of cardiac surgery cases. POAF may lead to adverse health outcomes such as stroke, thromboembolism, cardiac arrest, and mortality, and may develop long-term. Patients have a 2-fold increase in mortality risk and spend about 3.7 more days in the hospital and $16,000 more in medical costs during their visit. The mechanisms and risk factors of POAF are still poorly understood, yet a strong foundation of how a disease process occurs is needed to provide the most effective treatment. Current mechanisms that are postulated to contribute to POAF include an increase in sympathetic tone, oxidative stress, local and systemic inflammation, a trigger that induces atrial substrate changes, a driver to sustain POAF, and electrolyte disturbances such as hypomagnesemia. While needing more research, current risk factors include age, male sex, history of myocardial infarction or heart failure, hypertension, diabetes, obesity, and COPD. Treatments mostly include prophylaxis of repurposed drugs such as beta-blockers, statins, oral anticoagulants, antiarrhythmics, and Vitamin D and electrolyte supplementation. Autonomic denervation has also been a promising preventative measure for patients undergoing cardiac surgery. This critical review article provides an up-to-date and comprehensive summary of the pathophysiology of POAF, current clinical risk factors and management for POAF and discusses new pathways for further investigation.

Keywords: Atrial fibrillation; Cardiac surgery; Inflammation; Oxidative damage; POAF; Post-operative atrial fibrillation.

Figure 1:

An overview of the proposed preventative therapies for POAF. Pharmacological intervention includes β-Blockers, amiodarone, statins, and oral anti-coagulants. Surgical intervention includes autonomic denervation and minimally invasive surgery. Vitamin D and magnesium supplementation were also proposed as a preventative therapy for reducing the incidence of POAF.