Sudden cardiac death and its diagnostics

Czech version

Authors: M. Sepši ¹; M. Zeman ²; I. Synková ³; R. Gaillyová ³; I. Valášková ³; T. Novotný ¹; M. Šindler ²; D. Pospíšil ¹
Authors‘ workplace: Interní kardiologická klinika LF MU a FN Brno ¹; Ústav soudního lékařství, FN u sv. Anny v Brně ²; Oddělení lékařské genetiky, Pracoviště dětské medicíny, FN Brno ³
Published in: Kardiol Rev Int Med 2017, 19(4): 247-250

Overview

Sudden death is defined as death that has occurred suddenly, unexpectedly and within one hour of symptoms. According to aetiology, we distinguish between non-cardiac death and sudden cardiac death. The aetiology of sudden cardiac death is difficult to determine. Despite the extended possibilities of autopsy, 40% of sudden deaths remain unexplained. In these cases, we assume malignant arrhythmia to be the aetiology of death and we perform post-mortem genetic examination, primarily targeted at Long QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia. The list of examined genes is expanding. For the practical diagnosis, it is recommended to test four major genes: KCNQ1, KCNH2, SCN5A, RYR2. The examination of sudden cardiac death involves the collaboration of a forensic pathologist, geneticist, and cardiologist. During the autopsy, the samples for histopathological, microbiological and toxicological examinations are taken together with a sample of myocardium for genetic examination. Relatives are informed about the possibilities for their own clinical examination. Genetic examination helps determine the diagnosis and is followed by a cascade screening of the particular gene in the survivors in the case of a pathogenic mutation in the deceased. Cardiac examination of relatives (personal history with a focus on sudden death in the family, ECG, ergometry, and echocardiography) together with genetic testing helps diagnose and clarify the risk of sudden cardiac death for survivors. This comprehensive approach has been applied in the South-Moravian region for over 10 years. For more information, please visit www.nahlasmrt.cz.

Key words:
sudden cardiac death – post-mortem examination – molecular autopsy – genetic counseling – family – multidisciplinary approach

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