Diagnostic yield in sudden unexplained death and aborted cardiac arrest in the young: The experience of a tertiary referral center in The Netherlands

Background In sudden unexplained death (SUD) in the young (age 1–50 years), cardiologic and genetic examination in surviving relatives may unmask the cause of death in a significant proportion. The causes of aborted cardiac arrest (ACA) in this age group likely are similar to those in sudden cardiac death. However, there is a paucity of recent data on this topic. Objective The purpose of this study was to gain insight into the yield of current diagnostic strategies used in relatives of SUD victims and in ACA victims aged 1–50 years in our dedicated tertiary referral center. Methods We studied (1) all consecutive families who presented to the cardiology department for examination because of ≥1 first-degree related SUD victim aged 1–50 years and (2) all consecutive ACA victims aged 1–50 years who presented to the cardiology department from 1996 to 2009. Comprehensive cardiologic and genetic examination was performed in both populations. Results A certain or probable diagnosis was made in 47 (33%) of 140 SUD families, including 45 (96%) cases of inherited cardiac diseases. Long QT syndrome (19%) was the most prevalent diagnosis. In 42 (61%) of 69 ACA victims, the cause of the event was determined (inherited in 31 [74%]). Hypertrophic cardiomyopathy was most prevalent (17%). Conclusion The yield of the current diagnostic workup in relatives of young SUD victims is 33% and is almost twice as high in young ACA victims. Inherited cardiac diseases are predominantly causative in both groups.