Sudden Cardiac Death in Young Athletes: Causes, HCM and Marfan Syndrome

pediagenosis    November 08, 2026    Cardiovascular , Organ , science    Comment   

SUDDEN DEATH IN YOUNG ATHLETES

The most common cause of sudden cardiac death (SCD) in young athletes in the United States is hyper-trophic cardiomyopathy (HCM). Many athletes may have prodromal symptoms (e.g., near-syncope), but often the initial presentation is SCD. Massive hypertrophy of the ventricular septum (asymmetric septal hypertrophy) of 30 mm or more is a common feature of SCD. HCM is autosomal dominant and occurs in 1 of 500 persons. The genotype is present from birth, but the phenotype may not be apparent until adolescence. Other potential causes of SCD in young persons include congenital coronary anomalies, commotio cordis, Marfan syndrome, and long QT syndrome. Genetic and environmental factors such as smoking, medications, diet, lifestyle, electrolyte abnormalities, and myocardial infarction are associated with both HCM and long QT syndrome. The phenotype for long QT syndrome is prolongation of the QT interval.

Medical management of Marfan aortic disease consists of beta blockade to decrease the force and velocity of left ventricular contraction on the proximal aorta in Marfan syndrome. The rationale is that beta-blocker therapy reduces the stress on the weakened tissue of the aorta and thus slows the progression of aortic dilatation. Non-dihydropyridine calcium channel antagonists may provide similar results.

Surgical therapy of Marfan syndrome is considered when the risk of aortic dissection is apparent, with progressive enlargement of the aortic root. Two methods are used. With the traditional method, the surgeon replaces the aorta with a graft and the aortic valve with a mechanical valve. With the valve-sparing method, the ascending aorta is replaced with a graft and the valve reimplanted.