53 * Primary prevention ICDs in patients with ischaemic heart disease: does the potential benefit persist at generator change?

• DOI: 10.1093/europace/euu241.3
• Publication Date: 2014-10-08T19:28:16Z
• Authors: M. Chapman; J. M. McComb
• Keywords: 03 medical and health sciences; 0302 clinical medicine; 3. Good health

Aim: A scoring system derived from MADIT 2 used 5 clinical factors; Age >70 years, QRS >120msec, atrial fibrillation (AF), NYHA > II and blood urea nitrogen (BUN) > 26mg/dL to predict risk in primary prevention ICD recipients with ischaemic heart disease (IHD). Patients whose score was either 0 or ≥ 3 received no benefit from an ICD. The purpose of this retrospective, observational study was to determine how a patient's risk score changes from time of initial ICD insertion to time of first generator change. Method: Consecutive patients with IHD who received an ICD at a single centre and who underwent a first generator change at the same centre between 2008 and 2013 were identified and their case records were reviewed. The MADIT 2 risk score was calculated at time of first ICD implantation and at first generator change. Results: 83 patients received a primary prevention ICD or CRT-D. 80 were male. Mean age at insertion was 66.4 years and at generator change was 70.8 (mean time 4.4 years). Main reasons for generator change were elective replacement indicator (ERI) (n=52), elective upgrade (n=19) and lead dysfunction (n=10). One patient had an upgrade to CRT-D at ERI. At initial ICD insertion, the mean score was 1.96; 31 patients had a score of ≥3(19 received CRT-D) and 14 had a score of <1. At first device change, the mean score had risen to 2.67; 45 patients had a score of ≥3(34 had CRT-D) and 4 had a score of <1. Risk increased because of rise in BUN (n=21, 28% of score changes), the development of AF (n=18, 24%) and QRS widening (n=13, 17%). The risk increased in 10 of 14 with a low risk score of 0 at initial implantation. 38 were predicted to benefit at initial implantation; in 14 the score increased to ≥3 at generator change, so that benefit was no longer likely in these 37%. Conclusion: Risk scores rise significantly between initial primary prevention ICD insertion and generator change. These data suggest that 54% of patients may not benefit from their second ICD. 37% of patients who in theory initially gained benefit had lost this by the time of generator change due to a rise in risk score. This poses an ethical question about likelihood of benefit and appropriateness of routine generator change at ERI.