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Published on: October 17, 2018
Sudden cardiac death in a young male endurance athlete
Kevin D Seely1, Kentlee B Crockett1, Andrew Nigh1
1College of Osteopathic Medicine, Rocky Vista University, Ivins, UT, USA.
Insights
Sudden cardiac death in young athletes is a serious risk, even without known heart conditions. Genetic variations like CACNB2 may increase this risk, particularly with endurance sports and stimulants.
Area of Science:
- Cardiology
- Genetics
- Sports Medicine
Background:
- Sudden cardiac death (SCD) is a rare but critical event in young athletes.
- Hypertrophic obstructive cardiomyopathy is a common cause, but other genetic factors contribute to proarrhythmia.
- Routine genetic screening for these less common causes is not standard practice.
Observation:
- A young male athlete collapsed during a marathon and could not be resuscitated.
- Autopsy revealed no structural cardiac abnormalities, with death attributed to arrhythmia of undetermined origin.
- Postmortem genetic testing identified a CACNB2 gene variation, linked to arrhythmia and channelopathy.
Findings:
- The CACNB2 gene variation was found in a heterozygous state.
- Toxicology confirmed therapeutic levels of amphetamine.
- The combination of genetic predisposition and stimulant use may have potentiated the fatal arrhythmia.
Implications:
- This case underscores the risk of SCD in athletes with proarrhythmic genetic variations.
- Endurance sports and stimulant use can exacerbate underlying genetic risks for cardiac events.
- Further research into genetic screening and risk stratification in young athletes is warranted.
Abstract:
Sudden cardiac death (SCD) is a rare yet devastating event that can occur in young athletes. Although hypertrophic obstructive cardiomyopathy is the most common cause of SCD, some other genetic abnormalities have been identified as proarrhythmic. However, there is not routine screening for these other genetic abnormalities. Furthermore, consumption of caffeine, stimulant medication, or prolonged exercise can potentiate the underlying arrhythmic potential. In the event of SCD, advanced cardiac life support (ACLS) should be performed immediately and exactly. The authors present a case of an otherwise healthy young male who collapsed during a marathon and could not be resuscitated despite aggressive measures. After aggressive resuscitative efforts, the patient ultimately expired. A postmortem autopsy revealed no cardiac structural abnormalities, and the cause of death was determined to be cardiac arrhythmia of undetermined etiology. Postmortem genetic testing revealed a heterozygous variation in calcium voltage-gated channel auxiliary subunit beta 2 (CACNB2), a gene associated with arrhythmia and calcium channelopathy. Toxicology showed therapeutic levels of amphetamine. This case highlights the eminent risk of cardiac death in young athletes with proarrhythmic genetic variations, especially in the setting of endurance sport.
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