Atrial Fibrillation Begets Atrial Fibrillation A Study in Awake Chronically Instrumented Goats

摘要: Background In this study we tested the hypothesis that atrial fibrillation (AF) causes electrophysiological changes of myocardium which might explain progressive nature arrhythmia. Methods and Results Twelve goats were chronically instrumented with multiple electrodes sutured to epicardium both atria. Two 3 Weeks after implantation, animals connected a pacemaker artificially maintained AF. Whereas during control episodes AF short lasting (6±3 seconds), artificial maintenance resulted in increase duration become sustained (>24 hours) 7.1±4.8 days (10 11 goats). During first 24 hours median interval shortened from 145±18 108±8 ms inducibility by single premature stimulus increased 24% 76%. The effective refractory period (AERP) 146±19 95±20 (−35%) (S1S1, 400 ms). At high pacing rates shortening was less (−12%...