Long-term prognosis and emergency management for patients with an implantable cardioverter defibrillator: the EMERGE-ICD study

Objective. Patients with implantable cardioverter defibrillators (ICDs) are at risk of serious complications that are often treated in hospital emergency departments (EDs). The EMERG-ICD study (Emergency Department Management and Long-term Prognosis for Patients with ICDs) analysed management and long-term prognosis of ED patients with an ICD after an acute clinical event. Methods. Observational multicenter cohort study including consecutive adult patients with ICDs who came to 27 hospital EDs in Spain for treatment and were followed for 10 years. We collected clinical variables on presentation, ED case management variables, and the date and cause of death in each case. The primary outcome variable was all-cause mortality. Results. Five-hundred three patients were studied; 471 had structural heart disease (SHD) and 32 had primary electrical heart disease (PEHD). Beta-blockers were prescribed in the ED for 55% of the patients for whom they were indicated. Twenty-four (4.8%), 75 (15.7%), and 368 (73.2%) patients died during follow-up at 1 month, 1 year, and 10 years, respectively. Of these, 363 (77.1%) had SHD and 5 (15.6%) had PEHD (hazard ratio, 8.05 (95% CI, 3.3319.46). Among patients with SHD, the cause of death was cardiovascular in 66%. Mortality correlated significantly with seeking care for cardiovascular symptoms, advanced age, male sex, diabetes, a New York Heart Association score of 2 or more, severe ventricular dysfunction, and long-term amiodarone therapy. Conclusions. Prognosis after an acute clinical event is poor in patients with SHD and ICDs, mainly due to cardiovascular causes, especially among patients with associated comorbidities and cardiovascular complaints. Mortality is lower in patients with PEHD.