Higher NYHA functional class (P<0.0001) and failure to identify effective therapy during electrophysiologic study (P=0.0003) were the strongest independent predictors of cardiac death.
Cohort (n=239)
Does the identification of effective therapy during electrophysiologic study improve survival in patients with sustained ventricular tachycardia or ventricular fibrillation?
In patients with sustained ventricular tachyarrhythmias, the severity of heart failure and the failure to identify effective therapy during electrophysiologic study are the strongest independent predictors of mortality.
p-value: p=<0.0001
We analyzed data from 239 patients with sustained ventricular tachycardia or ventricular fibrillation to determine prognosis, predictors of survival, and the prognostic value of inducing arrhythmia and assessing therapy at the time of electrophysiologic study. Therapy predicted to be effective on the basis of electrophysiologic study was administered over a sustained period. There were 71 cardiac deaths, including 44 sudden deaths, during a mean (+/- S.D.) follow-up period of 14.8 +/- 13.9 months (range, one day to 67 months). At one, two, and three years, the actuarial incidence of sudden death was 17 +/- 3, 25 +/- 4, and 34 +/- 6 per cent, and that of cardiac death was 28 +/- 3, 37 +/- 4, and 50 +/- 6 per cent. Multivariate regression analyses demonstrated that the two strongest predictors of both sudden death and cardiac death were a higher New York Heart Association functional class (P less than 0.0001 for sudden death and P less than 0.0001 for cardiac death) and the failure of any therapy to be identified as potentially effective on the basis of electrophysiologic study (P = 0.0019 and P = 0.0003). The majority of deaths in patients with ventricular tachyarrhythmias were sudden, but the severity of heart failure was the strongest independent predictor of mortality. Response to therapy during electrophysiologic study was also an independent predictor of survival.
Swerdlow et al. (1983) conducted a cohort in Sustained ventricular tachycardia or ventricular fibrillation (n=239). Therapy predicted to be effective on the basis of electrophysiologic study vs. Failure to identify effective therapy was evaluated on Sudden death and cardiac death (p=<0.0001). Higher NYHA functional class (P<0.0001) and failure to identify effective therapy during electrophysiologic study (P=0.0003) were the strongest independent predictors of cardiac death.