Purpose: Despite the proven survival benefits of implantable cardioverter-defibrillators (ICDs) in the context of controlled clinical trials, there is paucity of data regarding routine clinical practice. The aim of this study was to investigate the predictors of appropriate/inappropriate ICD shocks and their impact on long-term mortality and morbidity in patients implanted for secondary sudden cardiac death (SCD) prevention. Methods: 327 consecutive patients (mean age 70.1) undergoing ICD implantation between Jan 2005 and Dec 2010 were included in this study. Baseline characteristics and semestral follow-up visits data were extrapolated from multicenter medical records. Logistic regression models were used to identify significant predictors of ICD shocks. The effect of appropriate and inappropriate shocks on the primary outcome of all-cause death or cardiovascular (CV) hospitalization was examined by means of Cox proportional hazard model adjusting for significant confounders. Results: Over a median follow-up of 34 months (IQR 19-53) 112 patients (34.2%) received an ICD shock. The occurrence of atrial fibrillation during follow-up and elevated resting heart rate were the two strongest predictors of inappropriate shocks (OR 4.57, 95% CI 1.18–17.68 and OR 1.04, 95% CI 0.99-1.09 respectively) whereas biventricular pacing had a borderline protective effect on the risk of appropriate shocks (OR 0.28, 95% CI 0.09-1.03). At multivariable survival analysis, all shock subtypes (appropriate, inappropriate, any shock) were significantly associated with the composite outcome of all-cause death or CV hospitalization (Table 1). Conclusions: In "real-world" patients implanted with ICDs for secondary SCD prevention the occurrence of defibrillator shocks is a common event that negatively influences patients' prognosis and quality of life. Therapeutic strategies aiming at slowing the underlying cardiac disease progression together with optimal device programming should always be attempted in order to improve ICDs net clinical benefit.
Appropriate and inappropriate defibrillator shocks: predictors and impact on prognosis in a cohort of patients implanted for secondary sudden cardiac death prevention.
CASTAGNO, Davide;BISSOLINO, Arianna;GAITA, Fiorenzo
2013-01-01
Abstract
Purpose: Despite the proven survival benefits of implantable cardioverter-defibrillators (ICDs) in the context of controlled clinical trials, there is paucity of data regarding routine clinical practice. The aim of this study was to investigate the predictors of appropriate/inappropriate ICD shocks and their impact on long-term mortality and morbidity in patients implanted for secondary sudden cardiac death (SCD) prevention. Methods: 327 consecutive patients (mean age 70.1) undergoing ICD implantation between Jan 2005 and Dec 2010 were included in this study. Baseline characteristics and semestral follow-up visits data were extrapolated from multicenter medical records. Logistic regression models were used to identify significant predictors of ICD shocks. The effect of appropriate and inappropriate shocks on the primary outcome of all-cause death or cardiovascular (CV) hospitalization was examined by means of Cox proportional hazard model adjusting for significant confounders. Results: Over a median follow-up of 34 months (IQR 19-53) 112 patients (34.2%) received an ICD shock. The occurrence of atrial fibrillation during follow-up and elevated resting heart rate were the two strongest predictors of inappropriate shocks (OR 4.57, 95% CI 1.18–17.68 and OR 1.04, 95% CI 0.99-1.09 respectively) whereas biventricular pacing had a borderline protective effect on the risk of appropriate shocks (OR 0.28, 95% CI 0.09-1.03). At multivariable survival analysis, all shock subtypes (appropriate, inappropriate, any shock) were significantly associated with the composite outcome of all-cause death or CV hospitalization (Table 1). Conclusions: In "real-world" patients implanted with ICDs for secondary SCD prevention the occurrence of defibrillator shocks is a common event that negatively influences patients' prognosis and quality of life. Therapeutic strategies aiming at slowing the underlying cardiac disease progression together with optimal device programming should always be attempted in order to improve ICDs net clinical benefit.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
