Rare genetic variants may raise risk of fatal arrhythmias in patients with less advanced coronary artery disease

Advanced coronary artery disease and the cardiac hypertrophy often associated with it is the most common cause of sudden cardiac death. However, in some cases, less advanced coronary artery disease and cardiac hypertrophy are established among the underlying causes of sudden death. According to the study, specific rare genetic variants may increase the risk of fatal arrhythmias and sudden death in patients with less advanced coronary artery disease.

Cardiac hypertrophy is associated with sudden cardiac death caused by coronary artery disease, particularly in younger individuals, when the severity of coronary artery stenoses does not fully explain the sudden death.

The objective of the University of Oulu's Cardiology Research Group was to study the role of hereditary factors in the development of cardiac diseases and in the increased risk of fatal arrhythmias. The genetic study was targeted at deceased patients with autopsy evidence of cardiac hypertrophy and only single vessel coronary artery disease without previously diagnosed coronary artery disease.

The study showed that rare genetic variants associated with cardiomyopathy were common in the deceased. Variants were observed in cardiac structure and function encoding genes. However, no significant variants were observed in the genes related to the electrical activity of myocardial cells. Approximately one in ten victims was found to have a gene defect that can potentially cause myocardial disease. In addition, approximately one in four victims was found to have a gene defect, the significance of which remained unclear.

The findings suggest that specific rare genetic variants may increase the risk of fatal arrhythmias and sudden death in patients with less advanced coronary artery disease. According to the researchers, methods should be developed for better identifying and treating individuals at risk.

The study was based on the FinGesture data, which consists of all the deceased shown to have died from sudden cardiac death in a forensic autopsy in the region of Northern Finland in 1998-2017 (n = 5,869).