Rabbits with chronic heart failure had a significantly higher incidence of ventricular fibrillation during acute myocardial ischemia compared to controls (76% vs 27%, P<0.01).
Does chronic heart failure increase the susceptibility to ischemia and reperfusion-induced arrhythmias in a rabbit model?
Rabbits with chronic heart failure exhibit enhanced susceptibility to ischemia and reperfusion-induced arrhythmias, potentially driven by delayed repolarization.
Tasa de eventos absoluta: 76% vs 27%
valor p: p=<0.01
The incidence of ventricular arrhythmias occurring during acute myocardial ischemia and reperfusion was studied in anesthetized rabbits with chronic heart failure. Cardiac failure was induced by volume and pressure overload and was characterized by marked hypertrophy (84%) and lower systolic aortic blood pressure (112 +/- 3 mmHg) than in controls (124 +/- 2 mmHg, P less than 0.01). During the first 20 min postcoronary artery ligation, the incidence and duration of ventricular fibrillation were greater in the heart failure group (76% and 485 +/- 77 s, respectively) compared with the control group (27% and 86 +/- 37 s, respectively, P less than 0.01). Reperfusion-induced arrhythmias after various ischemic durations were also more frequent in the heart failure group than in the control group. Papillary muscles taken from rabbits with heart failure showed a reduced diastolic potential and a prolonged action potential duration (APD90) compared with the control group (by 7 and 46%, respectively), but there was no change in maximum upstroke velocity. The present study established that rabbits with pronounced morphological signs of chronic heart failure have an enhanced susceptibility to ischemia and reperfusion-induced arrhythmias. As already described in situations of uncomplicated cardiac hypertrophy, a delay in the repolarization process could represent an arrhythmogenic mechanism in this model.
Bril et al. (Thu,) conducted a other in Chronic heart failure. Chronic heart failure vs. Control group was evaluated on Incidence of ventricular fibrillation during the first 20 min postcoronary artery ligation (p=<0.01). Rabbits with chronic heart failure had a significantly higher incidence of ventricular fibrillation during acute myocardial ischemia compared to controls (76% vs 27%, P<0.01).