Abstract 2757: Adhesive Epicardial Corticosteroids Prevent Post-Operative Atrial Fibrillation
Background/Objective: Postoperative atrial fibrillation (POAF) remains a common cause of morbidity. Epicardial drug delivery can increase efficacy and reduce systemic side effects, but is impractical for POAF because postoperative pericardial effusion/drainage causes rapid drug elimination. Hemostatic agents sprayed on the epicardium are vigorously adherent to the epicardium, allowing an admixed drug to remain in contact with the heart despite the presence of an effusion. The purpose of the current study is to evaluate a novel corticosteroid-fibrinogen mixture applied to the atrial epicardium at the time of surgery for prevention of POAF.
Methods: Talc was instilled into the pericardium in fifteen crossbred hounds to simulate postoperative inflammation. Permanent pacemakers were implanted to monitor atrial arrhythmias. A mixture of triamcinolone acetonide, 80mg, and fibrinogen sealant (Tisseel, Baxter Corp.) was sprayed onto the atria of study group animals (n=9), while control animals (n=6) received only Tisseel. After one week, pacemakers were interrogated for mode switch events and excised hearts were subject to histologic exam and tensile strength testing.
Results: POAF occurred in 6/6 (100%) controls but only in 3/9 (33%) study group animals (>100 inflammatory cells/40x field) was present in 6/6 controls vs. 1/9 study group animals (p=0.0002). The tensile strength within the atriotomy was not significantly different between the two groups (control=1.18+0.09N/suture vs. study=0.95+0.10N/suture, p=0.14). Plasma triamcinolone levels in the study group (0.2μg/dL) were much less than those seen in previous studies of intraarticular/intravitreous injections.
Conclusions: A mixture of triamcinalone and fibrinogen sealant sprayed onto the atria dramatically reduced the burden of POAF and reduced inflammatory cell infiltration. There was no change in the tensile strength of the atrial myocardium and plasma steroid levels were low. Clinical trials of this approach are warranted.