Indications and Effectiveness of ICD for Primary and Secondary Prevention in Patients Admitted in Ahvaz Imam Khomeini Hospital since 2017

Adv Biomed Res. 2023 Oct 28:12:233. doi: 10.4103/abr.abr_338_21. eCollection 2023.

Abstract

Background: Implantable cardioverter-defibrillators (ICDs) have been established for primary and secondary prevention of fatal arrhythmias and effectively reduce the rate of sudden cardiac death (SCD). This study aims to evaluate the indications and effectiveness of ICD for primary and secondary prevention of SCD.

Materials and methods: This retrospective study was conducted on 229 patients (136 for primary and 93 for secondary prevention) with ICD implantations in Imam Khomeini Hospital, Ahvaz, between 2017 and 2020. The incidence of arrhythmic events after implantation of ICDs was saved in electrograms, and the performed treatments (antitachycardia pacing (ATP)/shock) were recorded from the device memory.

Results: The indications for ICD implantation in primary and secondary prevention were different (P < 0.0001). The most common cause of ICD implantation for primary prevention was ischemic cardiomyopathy (ICMP, 90.4%) and for secondary prevention was ICMP (58.1%) followed by dilated cardiomyopathy (31.2%). During ICD implantation, 54 patients (39.7%) with ICD implantation for primary prevention and 50 patients (53.8%) for secondary prevention had arrhythmia (P = 0.043). The rate of appropriate therapies in patients with secondary prevention was higher than the primary prevention (57.9% vs. 42.1%), while the rate of inappropriate treatments in patients with primary prevention indication was more than the secondary prevention (63% vs. 37%) (P = 0.060).

Conclusions: ICMP was the main cause of ICD implantation for the prevention of SCD in both groups. At follow-up, the high prevalence of appropriate ICD therapy was observed in both groups, and this risk was slightly higher in the secondary prevention group.

Keywords: Arrhythmia; ICD; primary prevention; secondary prevention; sudden cardiac death.