Can We Prevent Sudden Cardiac Death in Athletes? In Search of Evidence-Based, Cost-Effective Screening

Abstract

Purpose of a New Project: To develop a novel screening strategy to prospectively establish predictors and to prevent sudden cardiac death (SCD) in athletes. Most cases of SCD are related to preexisting high-risk cardiovascular conditions (hr-CVC) - predominantly coronary artery anomalies (CAAs) and cardiomyopathies that are readily diagnosed with advanced imaging. Currently, there is considerable debate about the need and extent for cardiovascular preparticipation screening of physical training and athletes. At Texas Heart Institute, we recently founded a Center for Coronary Artery Anomalies (CCAA) with a purpose to investigate hr-CVCs and prevent SCD. METHODS: We are currently conducting two coordinated projects: 1) The MRI study - involving cardiac magnetic resonance imaging (cMRI) screening for hr-CVC in 10,000 middle-school children to identify carriers of hr-CVC. This is the first prospective MRI imaging screening study ever performed in a general population, aimed at establishing the prevalence of hr-CVC, while including a large and representative population, from various subgroups. Such program will use a simple clinical information form for cardiovascular symptoms, a modified screening protocol cMRI (no contrast/intravenous access, 5-7 min acquisition time) and a resting electrocardiogram. The subjects with hr-CVC will be referred to specialized centers, for final evaluation and disposition, according to agreed protocols, at 3 local institutions. 2) The Necropsy study - continuous series of 6,000 autopsies carried out over a 2-years period at the Harris County Forensic Center, referral center for the 4 million inhabitants in the Houston, Texas area. This project will be used to collect information about the incidence of the same hr-CVC and all different causes and modes of death in such population. This study will combine clinical data at the time of death (ECG, type of physical activity, previous participation in sports activities) and specific anatomic markers of severity of the hr-CVC. Initial rhythm at time of SCD (ventricular fibrillation, asystole or pulseless electrical activity) will be correlated with anatomical findings and evidence of acute myocardial infarction or previous myocardial scarring. Mortality at 5 years follow-up, in the screened general population and hr-CVC students, will be evaluated and compared to historical mortality databases. CONCLUSIONS: The ultimate purposes of the 2 studies are to establish: 1) prevalence of hr-CVC in different subgroups; 2) cost/efficiency of such screening, in the different subgroups; and 3) effect of instituting such pre-certification screening and work-up for prevention of SCD.