Prophylactic implantation of implantable cardioverter-defibrillator for the primary prevention of sudden cardiac death after myocardial infarction: protocol for systematic review and meta-analysis of randomised controlled trials

Abstract

Introduction Cardiovascular disease is a leading cause of death worldwide, of which coronary artery disease is the most common form. Sudden cardiac death (SCD) is a serious complication following acute myocardial infarction (MI), accounting for the highest percentage of all deaths in this population. Currently implantable cardioverter-defibrillators (ICDs) provide an acceptable method of primary prevention of SCD. However, the current literature is heterogeneous with regard to studies evaluating the benefits of ICDs for the primary prevention of SCD after MI, particularly relating to the timing of ICD implantation, risk stratification of patients for ICD implant selection and reporting non-rhythmic deaths after ICD implantation. Methods and analysis A meta-analysis will be performed to estimate the pooled effect size of randomised controlled trials (RCTs) examining the relationship between prophylactic transvenous ICD (TV-ICD) implantation and other medical therapies for primary prevention of SCD after MI. A comprehensive literature search and review will be performed using electronic medical databases including Scopus, Ovid MEDLINE, EMBASE (Ovid Platform), Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, ProQuest (Health and Medicine) and CINAHL (EBSCO) from January 1980 to June 2025. The literature search will be limited to peer-reviewed original studies carried out in human subjects and published in English. Type of study design will be limited to RCTs. The systematic review and meta-analysis will be developed according to the Joanna Briggs Institute Manual for Evidence Synthesis (2024 edition) and conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 guidelines. Data analysis will be performed according to a structured and predetermined analysis plan. The primary outcome of the study will be all-cause-mortality, for which Hazard Ratios (HRs) will be reported as a measure of effect with 95% CI. Based on data availability, subgroup analysis will be carried out. The effect sizes will be reported based on a random effects model. Expected study outcomes and dissemination This systematic review and meta-analysis will evaluate and provide primary evidence for the effectiveness of prophylactic implantation of TV-ICDs on all-cause mortality in patients who experienced MI, aiming for primary prevention of SCD after MI. The primary prevention of SCD after MI is an important goal to reduce community incidence of out-of-hospital cardiac arrests, improving patient survival rates and their quality of life after MI. Out-of-hospital cardiac arrests currently have a survival rate of less than 10% and could result in long-lasting neurological damage in those who survive. PROSPERO registration CRD42023456995.