Yucatan Miniswine Model of Atrial Fibrillation: Clinical Relevance

Atrial fibrillation was successfully induced in 4 of 6 animals within 80.3 ± 22.3 days of initiating pacing with three animals going into persistent AFib and one animal going into paroxysmal AFib. The definition of persistent AFib was that animals remained in AFib for more than 14 days after pacing was discontinued. Paroxysmal AFib was defined as AFib lasting less than 14 days. Activity levels decreased following persistent AFib onset, indicating a decline in overall health and quality of life. Histopathological analyses showed significant increases in fibrosis and loss of atrial cardiomyocytes after persistent AFib was induced in swine. Several anatomical and technical challenges, particularly related to vascular access and cardiac dimensions, were overcome through customized surgical strategies, including jugular venous cut-downs, lateral cervical ICM implantation, long vascular sheaths, custom styluses, and perioperative antibiotic coverage. These innovations were critical to establishing a robust and reproducible persistent AFib model.