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Introducción y objetivos La muerte súbita (MS) de personas jóvenes suele tener una causa genética, por lo cual la «autopsia molecular» puede tener implicaciones importantes para los familiares. El objetivo del estudio es evaluar el rendimiento diagnóstico de un programa de autopsia molecular mediante secuenciación masiva. Métodos Estudio prospectivo de una cohorte de pacientes consecutivos de edad ≤ 50 años y fallecidos por MS no violenta, a los que se realizó autopsia molecular mediante paneles amplios por secuenciación masiva, con posterior cribado familiar clínico y genético. Se analizan datos demográficos, clínicos, toxicológicos y genéticos. Resultados Se estudiaron 123 casos consecutivos de MS a edades ≤ 50 años. La incidencia de MS fue de 5,8 casos/100.000 individuos/año, a una media de edad de 36,15±12,7 años; 95 (77%) eran varones. La causa fue cardiaca en el 53%; MS inexplicada en el 24%, tóxicos en el 10,6% y MS del lactante en el 4%. De las cardiacas, el 38% por cardiopatía isquémica, el 7% por miocardiopatía arritmogénica, el 5% por miocardiopatía hipertrófica y el 11% por hipertrofia ventricular izquierda idiopática. Se indicó análisis genético en 62 casos (50,4%). Se hallaron variantes genéticas en 42 (67,7%), con una media de 3,4±4 variantes/paciente, que se consideraron patogénicas o probablemente patogénicas en el 30,6%. De las MS inexplicadas, hasta el 70% presentó alguna variante genética. El estudio familiar permitió detectar a 21 portadores o afectos, 5 de ellos estaban en riesgo, por lo que se indicó implante de desfibrilador. Conclusiones El estudio protocolizado y exhaustivo de la MS cardiaca de personas jóvenes es factible y necesario. En un alto porcentaje la causa es genética y, por lo tanto, existen familiares en riesgo que pueden beneficiarse de un diagnóstico y un tratamiento precoces para evitar complicaciones. (AU)

Introduction and objectives Sudden cardiac death (SCD) in young people often has a genetic cause. Consequently, the results of “molecular autopsy” may have important implications for their relatives. Our objective was to evaluate the diagnostic yield of a molecular autopsy program using next-generation sequencing. Methods We performed a prospective study of a cohort of consecutive patients who died from nonviolent SCD, aged ≤ 50 years, and who underwent molecular autopsy using large panels of next-generation sequencing, with subsequent clinical and genetic family screening. We analyzed demographic, clinical, toxicological, and genetic data. Results We studied 123 consecutive cases of SCD in persons aged ≤ 50 years. The incidence of SCD was 5.8 cases/100 000 individuals/y, mean age was 36.15±12.7 years, and 95 were men (77%). The cause was cardiac in 53%, unexplained SCD in 24%, toxic in 10.6%, and infant SCD in 4%. Among cardiac causes, ischemic heart disease accounted for 38% of deaths, arrhythmogenic cardiomyopathy for 7%, hypertrophic cardiomyopathy for 5%, and idiopathic left ventricular hypertrophy for 11%. Genetic analysis was performed in 62 cases (50.4%). Genetic variants were found in 42 cases (67.7%), with a mean of 3.4±4 genetic variants/patient, and the variant found was considered to be pathogenic or probably pathogenic in 30.6%. In unexplained SCD, 70% showed some genetic variant. Family screening diagnosed 21 carriers or affected individuals, 5 of whom were at risk, indicating an implantable cardiac defibrillator. Conclusions Protocol-based and exhaustive study of SCD from cardiac causes in persons aged ≤ 50 years is feasible and necessary. In a high percentage of cases, the cause is genetic, indicating the existence of relatives at risk who could benefit from early diagnosis and treatment to avoid complications. (AU)

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BACKGROUND: Sudden death (SD) in the young usually has an underlying genetic cause. In many cases, autopsy reveals unspecific and inconclusive results, like idiopathic left ventricular hypertrophy (LVH), nonsignificant coronary atherosclerosis (CA), and primary myocardial fibrosis (PMF). Their pathogenicity and their relation to SD cause is unknown. This study aims to evaluate the diagnostic yield of genetic testing in these cases. METHODS: SD cases, between 1 and 50 years old, with findings of uncertain significance (idiopathic LVH, nonsignificant CA and PMF) on autopsy were evaluated prospectively, including information about medical and family history and circumstances of death. Genetic testing was performed. RESULTS: In a series of 195 SD cases, we selected 31 cases presenting idiopathic LVH (n = 16, 51.61%), nonsignificant CA (n = 17, 54.84%), and/or PMF (n = 24, 77.42%) in the autopsy. Mean age was 41 ± 7.2 years. Diagnostic yield of genetic test was 67.74%, considering variants of unknown significance (VUS), pathogenic variants (PV) and likely pathogenic variants (LPV); 6.45% including only PV and LPV. Structural genes represented 41,93% (n = 13) of cases, while 38,7% (n = 12) were related to channelopathies. CONCLUSION: Molecular autopsy in SD cases between 1 and 50 years old, with findings of uncertain significance, has a low diagnostic yield, being VUS the most frequent variant observed.

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INTRODUCTION AND OBJECTIVES: Sudden cardiac death (SCD) in young people often has a genetic cause. Consequently, the results of "molecular autopsy" may have important implications for their relatives. Our objective was to evaluate the diagnostic yield of a molecular autopsy program using next-generation sequencing. METHODS: We performed a prospective study of a cohort of consecutive patients who died from nonviolent SCD, aged ≤ 50 years, and who underwent molecular autopsy using large panels of next-generation sequencing, with subsequent clinical and genetic family screening. We analyzed demographic, clinical, toxicological, and genetic data. RESULTS: We studied 123 consecutive cases of SCD in persons aged ≤ 50 years. The incidence of SCD was 5.8 cases/100 000 individuals/y, mean age was 36.15±12.7 years, and 95 were men (77%). The cause was cardiac in 53%, unexplained SCD in 24%, toxic in 10.6%, and infant SCD in 4%. Among cardiac causes, ischemic heart disease accounted for 38% of deaths, arrhythmogenic cardiomyopathy for 7%, hypertrophic cardiomyopathy for 5%, and idiopathic left ventricular hypertrophy for 11%. Genetic analysis was performed in 62 cases (50.4%). Genetic variants were found in 42 cases (67.7%), with a mean of 3.4±4 genetic variants/patient, and the variant found was considered to be pathogenic or probably pathogenic in 30.6%. In unexplained SCD, 70% showed some genetic variant. Family screening diagnosed 21 carriers or affected individuals, 5 of whom were at risk, indicating an implantable cardiac defibrillator. CONCLUSIONS: Protocol-based and exhaustive study of SCD from cardiac causes in persons aged ≤ 50 years is feasible and necessary. In a high percentage of cases, the cause is genetic, indicating the existence of relatives at risk who could benefit from early diagnosis and treatment to avoid complications.

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