Background: Alcohol is a known trigger for atrial fibrillation (AF). Meshoyrer and colleagues described a case report which demonstrated 44 episodes of AF were prevented with beta blocker (BB) pretreatment; one missed pretreatment resulted in AF. [EP Lab Digest, 19(7), July 2019]
Objective: To evaluate the efficacy of prophylactic BB therapy prior to alcohol consumption in preventing AF inducibility in a rat model.
Methods: An alcohol-induced AF model was developed in adult Sprague-Dawley rats of both sexes by administering alcohol (2g/kg, IP) 4 times, every other day. There were three groups tested: alcohol injected (EtOH), N = 10; saline injected (Control), N = 9; and BB (metoprolol 50 mg/kg, IP) treated before alcohol (EtOH+BB), N = 10. The day following the last injection, cardiac function was assessed with echocardiography and LV hemodynamics followed by in vivo AF inducibility tests.
Results: One rat in the alcohol group died suddenly. All other animals completed the study. Alcohol exposure did not significantly impact cardiac function or LV hemodynamics. Figures show AF inducibility (left) and average AF duration (right) for each group. Alcohol exposure significantly increased AF inducibility (1/9 in Control versus 8/9 in EtOH group, P = 0.002) and AF duration (0.16 + 0.48s in Control versus 4.76 + 9.64 s in EtOH group, P = 0.005). When compared to EtOH group, BB pretreatment significantly reduced AF inducibility (4/10, P = 0.04) and duration (0.27+ 0.63 s, P = 0.01).
Conclusion: Alcohol exposure significantly increases AF inducibility in rats. Prophylactic metoprolol treatment prior to alcohol exposure significantly reduced AF in this animal model.