The annual incidence of sudden cardiovascular death in high school athletes is probably 1 in 200,000. (1)
The most common cause of sudden death in this group is hypertrophic cardiomyopathy (36%). In this disease the heart muscle is abnormally thickend. This can be screened for with an echocardiogram (an ultrasound heart scan).
The next most common cause is congenital coronary artery anomalies (17%). In this disease one of the coronary arteries arise from the aorta in an abnormal position or arise from the pulmonary artery*. The most common can sometimes be detected by an echocardiogram but if this problem is strongly suspected then the patient needs a CT angiogram or MR angiogram.
*6-24-2017: See the outstanding post ALCAPA – Anomalous Left Coronary Artery from the Pulmonary Artery BY Dr. SEAN FOX · PUBLISHED MAY 12, 2017 of Pediatric EM Morsels
In 8% of sudden death there is left ventricular hypertrophy (heart muscle thickening) which may be related to hypertrophic cardiomyopathy. An echocardiogram should detect this.
There are many other less common causes of sudden death including ion channelopathies (3%) which are heart electrical system abnormalities (like long QT syndrome) screened for with a family history of sudden death and with an electrocardiogram.
Coronary artery disease (cholesterol build up in the heart arteries) is the most common cause of sudden death in athletes over 40 years old but accounts for only 3% of sudden death in young athletes. This problem might or might not cause an abnoramlity in the electrocardiogram. Because it is so rare in young people other screening tests (exercise stress test, imaging stress test, CT angiogram) are not indicated.
In aortic rupture, the aorta the blood vessel leaving the heart suddenly tears open and the patient quickly bleeds to death. This also is very rare and acounts for 2% of the sudden deaths. It can occur in patients with Marfan’s syndrome. These patients may be identified prior to catastrophy by finding an enlarged aorta on echocardiogram.
Other uncommon causes of cardiovascular sudden death are discussed in the article. (1)
The big question is how hard should we look for these rare disease that account for a tiny fraction of teen deaths (auto accidents being the biggest cause of death by far).
The AHA preparticipation screening recommendations (1) do not recommend routine screening electrocardiograms and echocardiograms.
However, some hospitals and physician practices offer low cost electrocardiogram and echocardiogram screenings. (2)
However, if I were a parent with a high school athlete, I would probably not have my child screened with an electrocardiogram and echocardiogram. In an upcoming blog “Why Not Screen High School Athletes with an electrocardiogram and echocardiogram?”, I’ll go over the risks of screening.
(1) Recommendations and Considerations Related to Preparticipation Screening for
Cardiovascular Abnormalities in Competitive Athletes: 2007 Update. Circulation. 2007;115:1643-1655
(2) Community Hospital in Indianapolis, for example, offers a $25 screening electrocardiogram and echocardiogram. Details are available here.