Incidence of arrhythmias in a large cohort of patients with current implantable cardioverter-defibrillators in Spain: results from the UMBRELLA Registry

• Published in: Europace (London, England) Vol. 18; no. 11; pp. 1726 - 1734
• Main Authors: Fontenla, Adolfo, Martínez-Ferrer, Jose B, Alzueta, Javier, Viñolas, Xavier, García-Alberola, Arcadi, Brugada, Josep, Peinado, Rafael, Sancho-Tello, Maria J, Cano, Alicia, Fernández-Lozano, Ignacio
• Format: Journal Article
• Language: English
• Published: England 01.11.2016
• Subjects: Aged; Cardiac Resynchronization Therapy - adverse effects; Death, Sudden, Cardiac - prevention & control; Defibrillators, Implantable - adverse effects; Female; Humans; Incidence; Kaplan-Meier Estimate; Male; Middle Aged; Multivariate Analysis; Primary Prevention; Proportional Hazards Models; Prospective Studies; Registries; Secondary Prevention; Spain; Tachycardia, Ventricular - epidemiology; Tachycardia, Ventricular - etiology; Ventricular arrhythmias; Inappropriate shocks; Implantable cardioverter-defibrillator; Appropriate shocks
• ISSN: 1099-5129; 1532-2092
• DOI: 10.1093/europace/euv393

The benefit of implantable cardioverter-defibrillators (ICDs) in patients at risk of sudden death has been established in randomized clinical trials (RCTs) using the ICD models available at the time. However, observational large-scale data on the incidence of arrhythmias in up-to-date ICDs implanted according to the current guidelines are scarce. The aim was to assess the incidence of arrhythmias in a large, current ICD population based on a blinded peer review of the detected episodes. UMBRELLA is a multicentre, observational registry of ICD patients followed by remote monitoring. Stored episodes were classified by a blinded committee of experts. Subgroup analyses were based on clinical profiles established by previous pivotal RCTs of ICDs. Of 1514 enrolled patients, 605 (39.9%) patients had 5951 episodes after 26 ± 17 months follow-up, being 3353 of them (56.3%) sustained ventricular arrhythmias (SVA), and 13.2% of SVA were self-terminated. Appropriate and inappropriate shocks occurred in 11.6 and 5% of patients, respectively. The 3 years cumulative incidence of SVA was 25% (95% CI: 21-28%) in primary prevention patients and 41% (95% CI: 36-47%) in secondary prevention patients (P < 0.001). Male gender, secondary prevention, and atrial fibrillation as basal rhythm were significantly related to a higher incidence of SVA. This real-world analysis suggests that modern ICD patients have a low rate of appropriate and inappropriate shocks. The risk of SVA in secondary prevention patients is less than what has been reported in RCTs.