Assessing the Cost and Resource Use Impact of Implantable Cardiac Defibrillator Shocks in the UK CareLink Population.

Objective: High voltage devices (implantable cardiac defibrillators (ICDs) and cardiac resynchronization therapy defibrillators referred to jointly as ICDs) reduce rates of sudden cardiac death in patients with cardiovascular disease. However, shocks from ICDs may be associated with healthcare resource use (HCRU) and costs. The aim of this study was to estimate the costs associated with both appropriate and inappropriate shocks from ICDs. Methods: Patients with appropriate and inappropriate shocks from ICDs were identified via CareLink data from Liverpool Heart and Chest Hospital between March 2017 and March 2019. The devices were SmartShock activated, with anti-tachycardia pacing. Costs were estimated according to the dominant episode of healthcare, from an NHS payer perspective. Results: There were 2445 patients on the CareLink system with ICDs. Over the two-year period, HCRU data from 143 shock episodes among 112 patients were reported. The total cost for all shocks was £252,552 with mean costs of £1608 and £2795 for appropriate and inappropriate shocks respectively. There was substantial variation in HCRU between shock episodes. Conclusion: While there was a low rate of inappropriate shocks from ICDs, there were still substantial HCRU and costs incurred. In this study, the specific HCRU was not costed independently, meaning the costs reported are likely to be a conservative estimate. Whilst every attempt to reduce shocks should be made, appropriate shocks cannot be avoided. Strategies to reduce the incidence of inappropriate and unnecessary shocks should be implemented to reduce overall health care costs associated with ICDs.