Dominant and Non-Dominant Frequency Structure of Evoked Ventricular Fibrillation in Dogs with Myocardial Ischemia

Resumo

The first 10 min of electrically provoked ventricular fibrillation in dogs with ischemic heart disease were characterized by organized myocardial activity evidenced by the dominant ECG frequency structure. During the first 2 min of ventricular fibrillation, low-frequency oscillations (4-7 Hz) dominated, while on min 3 to 10 after the onset of fibrillation, the dominant frequencies were low and medium (4-12 Hz). After 10-min fibrillation, the oscillations became non-dominant. Thus, ischemic myocardium maintains the organized structure of ventricular fibrillation for the first 10 min, which is important for the development of automatic diagnostics of abnormal cardiac activity in humans.