Background: Most cases of sudden cardiac deaths are caused by sustained ventricular tachyarrhythmias and implantable cardioverter defibrillators (ICD) are recommended for patents resuscitated from sudden cardiac death or life-threatening ventricular tachyarrhythmia. However the prognosis or efficacy of ICD therapy in patients with idiopathic ventricular tachyarrhythmias are uncertain. The purpose of this study was to evaluate the efficacy of ICDs in patients with idiopathic ventricular tachyarrhythmias.
Methods: The patients who implanted ICDs from 8 general hospitals in Young-Nam Province of South Korea were retrospectively enrolled in this study. The clinical data from the patents who implanted ICDs after events of idiopathic ventricular tachyarrhythmias were reviewed and analyzed. Idiopathic ventricular tachyarrhythmias included idiopathic ventricular fibrillation (VF) and life-threatening idiopathic ventricular tachycardia (VT).
Results: Among 358 patients, 65 patients (43 males, mean age 55.4 ± 16.5 years) implanted ICDs because of idiopathic ventricular tachyarrhythmias. The patients consist of 36 patients (55.4%) with VF and 29 (44.6%) with VT, respectively. Mean follow up duration was 27.1 ± 26.8 months and mean ejection fraction was 61.6 ± 7.9%. Total mortality was 4.6 % (3 patients) and 30.8% (20 patients) experienced at least one appropriate therapy. However, survival analysis didn’t show any differences of clinical events between two types of ventricular tachyarrhythmias.
Conclusions: This study demonstrated that about 35.4% of ICD implanted patients with idiopathic ventricular tachyarrhythmias experienced at least one appropriate shock or all-cause death. But, there were no differences in incidence of clinical events between the types of tachyarrhythmias.