NONLINEAR DYNAMICS IN VENTRICULAR-FIBRILLATION

Electrogram recordings of ventricular fibrillation appear complex and possibly chaotic. However, sequences of beat-to-beat intervals obtaine d from these recordings are generally short, making it difficult to ex plicitly demonstrate nonlinear dynamics. Motivated by the work of Sugi hara on atmospheric dynamics and the Durbin-Watson test for nonlineari ty, we introduce a new statistical test that recovers significant dyna mical patterns from smoothed lag plots. This test is used to show high ly significant nonlinear dynamics in a stable canine model of ventricu lar fibrillation.