Open AccessAppropriate Therapy But Not Inappropriate Shocks Predict Survival in Implantable Cardioverter Defibrillator Patients
Author(s) -
Dichtl Wolfgang,
Wolber Thomas,
Paoli Ursula,
Brüllmann Simon,
Stühlinger Markus,
Berger Thomas,
Spuller Karin,
Strasak Alexander,
Pachinger Otmar,
Haegeli Laurent M.,
Duru Firat,
Hintringer Florian
Publication year - 2011
Publication title -
clinical cardiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.263
H-Index - 72
eISSN - 1932-8737
pISSN - 0160-9289
DOI - 10.1002/clc.20910
Subject(s) - medicine , implantable cardioverter defibrillator , sudden cardiac death , secondary prevention , shock (circulatory) , retrospective cohort study , cardiology , defibrillation , disease , intensive care medicine
Background: Inappropriate implantable cardioverter defibrillator (ICD) shocks have been linked to a worse clinical outcome due to direct myocardial injury. Hypothesis: The occurrence of ventricular tachyarrhythmia indicating progression of the underlying heart disease, but not the ICD shock itself, has prognostic impact in clinical routine. Methods: In a retrospective study, 1117 recipients of an ICD were analyzed with respect to appropriate and inappropriate therapies and survival. Results: During a mean follow‐up of 2.92 years, appropriate therapy occurred in 27.7% and 54.0% of patients who had received an ICD for primary and secondary prevention of sudden cardiac death (SCD), respectively ( P< 0.0001). Inappropriate shock therapy occurred in 15.0% and 25.4% of patients who had received an ICD for primary and secondary prevention of SCD, respectively ( P = 0.122). Appropriate ICD therapy had a strong impact on overall survival ( P< 0.0001), and this association was found both in primary ( P< 0.0001) and secondary ( P = 0.002) prevention of SCD. Inappropriate ICD shocks had no impact on total mortality, neither in primary nor secondary prevention of SCD. Conclusions: Inappropriate shocks do not affect survival, in strong contrast to appropriate ICD therapy. Our study does not support the hypothesis that shock therapy in itself worsens clinical outcome. However, it confirms that appropriate ICD therapy is a warning sign and should prompt physicians to consider additional treatment strategies. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.