Sudden death syndrome in young athletes
Nontraumatic sudden death in young athletes is always disturbing, as apparently invincible athletes, become, without warning, victims of silent heart disease. Despite public perception to the contrary, sudden death in young athletes is exceedingly rare. It most commonly occurs in male athletes, who have estimated death rates nearly fivefold greater than the rates of female athletes. Congenital cardiovascular disease is the leading cause of non-traumatic sudden athletic death. Screening athletes for disorders capable of provoking sudden death is a challenge because of the low prevalence of disease, and the cost and limitations of available screening tests. Current recommendations for cardiovascular screening call for a careful history and physical examination performed by a knowledgeable health care provider. Specialized testing is recommended only in cases that warrant further evaluation.
A sudden death is at least as devastating to the primary care/sports medicine community. Physicians are humbled when an asymptomatic athlete with an apparently normal clinical examination dies suddenly.
1. Estimated death rates were fivefold higher in male athletes than in female athletes (7.47 versus 1.33 per million athletes per year).
2. Estimated death rates were twofold higher in male college athletes than in male high school athletes (14.5 versus 6.6 per million athletes per year).
3. Noncardiac causes of death accounted for 22 percent of the cases.
Sudden deaths in younger athletes were more often associated with congenital cardiovascular structural abnormalities, while sudden cardiac deaths in older athletes were more often associated with acquired atherosclerotic cardiovascular disease. The simple epidemiologic observation that the prevalence of atherosclerosis increases with age appears to begin to have its impact on sudden death etiologies around age 30 to 35.While atherosclerosis has some role before age 35, it is clearly the predominant cause after that age.
1. HYPERTROPHIC CARDIOMYOPATHY
Hypertrophic cardiomyopathy is an autosomal-dominant congenital disorder characterized by left ventricular outflow obstruction with asymmetric septal hypertrophy and marked disarray of ventricular muscle fibers. It is thought that this condition could predispose persons to malignant ventricular arrhythmias leading to syncope or sudden death.
Hypertrophic cardiomyopathy is often clinically silent, but a personal or family history of unexplained syncope, especially effort syncope or sudden-death events, is an important clinical clue. The diagnosis is best confirmed with three-dimensional and M-mode echocardiography.
2. CONGENITAL CARDIOVASCULAR AND ACQUIRED CORONARY DISEASE
Congenital coronary anomalies are multiple, the most common being misplaced aortic ostium, in which the right main coronary arises from the ascending aorta or the left main and right coronary artery arises from the right sinus of Valsalva. These conditions are difficult to identify unless complaints of early fatigue, angina or exercise-induced syncope lead to a directed evaluation. These autopsyproven coronary anomalies occurred in 62% of asymptomatic persons. This diagnosis is confirmed by thin slice 128 fast CTA.
Tragically, acquired premature coronary artery disease can appear in the athlete under age 30. Genetic predisposition plus other risk-factor prevalence can sometimes lead to coronary events resulting from typical atherosclerosis.
Acute myocarditis is a rare but potentially devastating condition that is most commonly caused by viruses. Coxsackie B virus has been implicated in 50 percent of cases.Early symptoms, if present, may include exercise intolerance and congestive heart failure symptoms with dyspnea, cough and orthopnea. Subtle clinical signs include tachycardia in the absence of fever, pulsus alternans and other clinical signs of heart failure (e.g., S3 gallop, soft apical murmur, distended neck veins, peripheral edema). Most patients with myocarditis present with sudden death secondary to a ventricular arrhythmia and had few, if any, prodromal signs or symptoms.
4. Marfan's Syndrome
Marfan's syndrome, with its lethal association with ruptured aortic aneurysms, deserves particular note because of helpful clinical clues that make it a screenable condition by thin slice 128 fast CTA.
In addition, other preventable conditions should be noted, such as cocaine use (associated with coronary artery spasm) and anabolic steroid use (potential association with hypertrophic cardiomyopathy).
Screening Strategies and Dilemmas
Our Screening program include three dimension echocardiogram and thin slice 128 fast CTA.
Cardiovascular abnormalities should be judged with respect to the Bethesda Conference consensus panel recommendations for the final determination of eligibility for future athletic competition. The Bethesda report classifies individual sports according to the type and intensity of exercise and the danger of bodily injury from collision, or the consequences of syncope. This comprehensive report provides useful guidance to physicians with regard to the acceptable medical risks of athletic participation in patients with known cardiovascular abnormalities.