Pathological findings limited to the specialized conduction sys- tem were demonstrated in 22% of cases.S13-9 A misdiagnosis of cardiomyopathy was reported in 37% of referred cases that were ultimately deter- mined to be structurally normal. The etiologic data for specialized cardiac evaluation are not general- izable to the overall population because of skew- ing of age at the time of SCD. In another study of SCD patients at ages ranging from <1 year to >80 years (mean, 38.2 years; median, 38 years), the peak incidence of SCD occurred between the ages of 31 and 60 years, with a 5- to 7-fold excess of males/females in that age range.S13-10 For the overall group, 42% of SCD were due to ischemic heart disease, 12% viral myocarditis, and 5% cardiomyopathy, with 15% being unexplained by autopsy. For the subgroup <35 years of age, 13.5% were attributed to ischemic heart disease and 24.9% were unexplained. In the subgroup >55 years of age, only 0.8% were unexplained. In patients who die suddenly despite an ICD, interrogation of the ICD is important to confirm proper device functioning and can provide infor- mation on the mechanism of death. 2. Comprehensive cardiac screening including 12-lead ECG, possible signal averaged ECG, echocardiogram, and ambulatory rhythm moni- toring or exercise testing of first-degree relatives of decedents with sudden unexpected death may identify a probable heritable cardiac cause of death in up to 30% of cases.S13-11 S13-13 Genetic testing should be targeted based on the results of Genetic testing in selected first-degree relatives may result in identification of inherited conditions including long QT syndrome, catecholaminergic polymorphic ventricular tachy- cardia, Brugada syndrome, arrhythmogenic right ventricular cardiomyopathy, and HCM in 4% to 3. 