Aims
Guidelines recommend the use of an implantable cardioverter-defibrillator (ICD) and/or cardiac resynchronization therapy (CRT) device based on the results of randomized controlled trials (RCTs), typically with selected patients and short follow-up.

Methods and results
We describe the 5 year survival rate and use of hospital services following ICD and CRT implantation in England from April 2011 to March 2013 using the national hospital administrative database covering emergency department visits, inpatient admissions, and clinic appointments, linked to the national death register. Five-year survival was 64% after ICD implantation and 58% after CRT implantation, with median survival times of 6.8 and 6.2 years, respectively. Hospital use was high in both device groups, for the 5 years prior and after implantation, peaking around the implantation date. Most hospital activity was not primarily related to heart failure. Healthcare costs were dominated by admissions, but emergency department and clinic activity were both high. Only the CRT group saw total per-patient costs fall after the index month (implantation), driven by a slight fall in the heart failure admission rate. Patients were typically older than in the trials, but with similar co-morbidity except for substantially more atrial fibrillation and less dementia. Survival and device complications were similar to the RCTs.

Conclusions
Clinical and cost-effectiveness assessments of ICD and CRT implantation are supported by real-world data, although the prevalence of atrial fibrillation remains substantially higher than in the RCTs.