Cardiac symptoms before sudden cardiac death caused by hypertrophic cardiomyopathy: a nationwide study among the young in Denmark

Abstract

Aims: Hypertrophic cardiomyopathy (HCM) is a frequent cause of sudden cardiac death (SCD) among the young (SCDY). The aim of this study was to characterize symptoms before SCDY due to HCM.

Methods and results: Through review of all death certificates, we identified all SCDs in Danes aged 1-35 years in 2000-2009. Nationwide we included all deaths (n = 8756) and identified 431 autopsied SCDYs. All available records from hospitals and general practitioners were retrieved. To compare symptoms, we included a control groups consisting of traffic accident victims (n = 74). In the 10-year study period, 431 autopsied SCDY cases were reviewed and 38 cases (9%) were included, of which 22 (58%) had morphologic findings diagnostic of HCM and 16 (42%) had findings suggestive, but not diagnostic, of HCM ('possible HCM'). Cardiac symptoms >1 h prior to death were reported in 21 (55%) of cases, and 16 (42%) sought medical attention. One (1%) control had cardiac symptoms before death. Consequently, a significantly higher proportion of cases had cardiac symptoms before death and cases more often sought medical attention than controls (P < 0.001).

Conclusion: In conclusion, this nationwide study demonstrates a high frequency of cardiac symptoms prior to death in SCDY cases who died of HCM, as 55% had cardiac symptoms and nearly half of the cases sought medical attention.

Keywords: Hypertrophic cardiomyopathy; Implantable cardioverter defibrillator; Signs and symptoms; Sport-related sudden cardiac death; Sudden cardiac death; Syncope.