Single chamber implantable cardioverter defibrillator compared to dual chamber implantable cardioverter defibrillator: less is more! Data from the German Device Registry

In patients with high risk for sudden cardiac death the implantation of a defibrillator is an established treatment. However the benefits and risks for patients in accordance to the number of the leads are not clear. Even in the current guidelines a recommendation to this question is missing. We analyzed advantage and disadvantages of single-chamber implantable cardioverter defibrillators (VVI-ICD) versus dual-chamber implantable cardioverter defibrillators (DDD-ICD) in the prospective German Device Registry. The data of 2240 patients who underwent ICD implantation in 45 German Centers between January 2007 and March 2011 were included in a prospective device registry (VVI: n = 1629, male = 1358, EF = 34% ± 13%; DDD: n = 611, male = 491, EF = 35% ± 14%). The in-hospital complications were significantly higher in the DDD-ICD group with higher revision/device complication rates (3.0% vs. 1.2%; p = 0.003) but also higher mortality rate (1.0% vs. 0.1%; p < 0.001). Regarding the adjusted data at 1-year follow-up DDD-ICD caused more device revisions, but no difference in rehospitalization and mortality. It is still unclear whether DDD-ICD may be beneficial for patients with preserved sinus and atrioventricular nodal function. Our data show that the decision of the operator to choose a DDD-ICD in these patients must be taken very carefully. By choosing a DDD-ICD the patient is exposed to a significantly higher periprocedural complication rate and higher in-hospital mortality. In absence of relevant bradycardias implantation of a DDD-ICD is not justified.