Cardiovascular Screening: Tailoring the Preparticipation Exam

Paul D. Thompson, MD with Carl Sherman

In Brief: While the critical task of the preparticipation cardiac examination is identifying life-threatening conditions, care must be taken not to exclude healthy individuals from activity. The vast majority of exams will be negative, but the physician should be alert to such potentially lethal conditions as hypertrophic cardiomyopathy, aortic stenosis, and Marfan syndrome. A history of symptoms during exertion, certain features of physical appearance, and clinical findings require referral to a cardiologist. Although the cardiac examination needn't involve complex tests, it must permit recognition of abnormal heart sounds and other signs of pathology. In the older athlete, coronary heart disease is the principal risk, and the examination should be tailored accordingly.

Cardiovascular health is a central concern. While the sudden cardiac death of an apparently healthy athlete is shocking—the 28-year-old Russian skater Sergei Grinkov, a two-time Olympic gold medalist, is a recent example—such events are quite rare. Since the preparticipation examination is, by its nature, relatively brief, it is important to have a clear idea of what it can and cannot reasonably accomplish. Typical subjects are school-aged athletes and older recreational athletes who plan to begin an exercise program.

What is the goal of the preparticipation exam?

The goal is to listen and look for signs of a cardiac problem that could kill or cause serious harm. A secondary aim is to direct athletes whose ability to participate may be limited by heart disease: to determine, for example, when golf is an acceptable activity but track is not.

What mind-set do you bring to the examination of the young athlete?

I actually bring a low level of suspicion. Remember that this is screening generally required by the school, and that most of these kids are healthy and have no complaints. They didn't collapse on the field. Most of the things you come across will be variants of normal.

So don't overreact: A real danger is unnecessarily limiting the activity of a healthy young athlete. This doesn't mean, of course, that you should ignore findings that may require further evaluation. Trust your senses. If you see or hear something you don't understand or that makes you uncomfortable, by all means refer the patient to a cardiologist. If the assessment turns out negative, there's nothing to regret.

What conditions do you look for?

Hypertrophic cardiomyopathy (HCM), aortic stenosis, and Marfan syndrome are the most important ones (1). You should also be thinking about things like anomalous coronary arteries, but these are unlikely to be picked up in a person who has no symptoms.

How do you start the exam?

Begin with a good history. You want to know if the athlete has had symptoms of any sort. Among the questions I consider most important:

• Are you more short of breath during exercise than your friends are?
• Can you keep up with your peers?
• Have you passed out while actually exercising?
• Do you get any discomfort in your chest when you are active?

I tend to avoid the word "ever." Many kids will think up things to make the doctor happy, and if you ask if they have "ever" had various symptoms, you'll get a lot of positive answers that don't mean much. It would be different, of course, if the athlete came in because of a complaint.

I would ask if an athlete has ever been disqualified from participation for health reasons. Or if they have ever been diagnosed with heart disease or a heart murmur.

What about family history?

Family history is important, but a lot of kids don't know much about their family histories. A good question is whether the patient has had any brothers, sisters, or other close relatives who died before the age of 30.

How do you do the physical examination?

First thing, take a good look at the athlete. Appearance can tell you a lot. An unusual-looking youth—very tall, thin, with a wide "wingspan"—may have Marfan syndrome. In this disease, connective tissue throughout the body is deficient because it lacks fibrillin. Also, because the aorta is dilated and dangerously thin, it can rupture without warning when blood pressure goes up during exercise. A child who has Marfan syndrome may drop dead while playing basketball or volleyball.

Ask about a family history of Marfan syndrome. And look for the "wrist sign" (long, thin fingers that can completely encircle the wrist) and the "thumb sign" (the thumb protrudes when the fingers close around it). When the arms are turned out and held at the sides, they angle away from the body at more than the normal 17°.

These individuals are typically myopic, because the shape of the eyeball is elongated. Their skin often has bluish stria. Asymmetric pectus excavatum, or pectus carinatum, is common.

A different physical appearance unrelated to Marfan syndrome should alert you to the possibility of coarctation of the aorta. These patients have an upper body noticeably more developed than the lower body, because their legs did not grow normally.

What can blood pressure tell?

For anyone high school age or older, I'd use the adult definition for normal blood pressure: 140/90 mm Hg. I wouldn't get excited about very mild hypertension—it doesn't necessarily track into adulthood, and it's not grounds to exclude an athlete from participation.

A lot of kids will have slightly elevated pressure because they're nervous: "White coat hypertension" is a common phenomenon. Blood pressure taken by a nurse is more likely to be accurate. Also, use the proper size cuff. A big athlete needs a big cuff.

Truly elevated blood pressure should be evaluated further and treated accordingly before athletic participation is approved.

What do you look for in checking pulses?

If blood pressure is elevated, take the radial and femoral pulse simultaneously. Femoral pulse delay is a sign of coarctation of the aorta.

Pay attention to regularity, rate, and intensity of pulses. Arrhythmias are not necessarily cause for alarm. If I hear a few isolated premature ventricular contractions, I wouldn't go chasing them; a lot of healthy people have some extra beats. Generally, I judge extra beats by the cardiac company they keep. If an athlete has a lot of them, and a history of passing out, he or she needs a workup.

Feel the carotid pulse—there should be a reasonable upstroke. If you can't feel the carotid in a young person, think about aortic stenosis.

How do you evaluate heart sounds?

I don't recommend a very sophisticated cardiovascular exam (2,3). If it's quiet enough, I don't mind simply lining the kids up in a gym—assuming the history is fine—to listen to heart sounds.

Listen to the heart while the individual is standing or sitting, not lying down. The supine position allows blood to return from the legs, increasing the stroke volume of the right ventricle, and the greater flow causes murmurs in a lot of young hearts.

Athletes, in particular, are prone to normal murmurs. Their slower heart rate increases the stroke volume, and all that blood going through a normal-sized valve is liable to produce a murmur. Age and size per se don't particularly affect the frequency of murmurs.

How do you identify abnormal murmurs?

Actually, the only way to get better at listening to hearts is to listen to a lot of them. But there are a few important guidelines to keep in mind.

It's good to recognize when a diastolic murmur exists, but few of them will kill you. A systolic murmur may indicate coarctation, atrial septal defect, or aortic stenosis. The louder a systolic murmur is, the more likely it's cause for concern. A murmur that radiates—up to the neck, to the apex, or a long way in the heart—deserves a closer look.

One way to identify the murmur of HCM is to listen while the athlete does the Valsalva maneuver. It will grow considerably louder as the chamber size gets smaller and the hypertrophic septum obstructs outflow. A murmur caused by HCM is louder when the patient stands, softer when he or she lies down—the opposite pattern from normal murmurs.

What do clicks signify?

Any extra noise usually implies pathology, but clicks may or may not have clinical significance. If you're not sure what they mean, have a cardiologist listen to them.

Most often, an apical midsystolic click reflects mitral valve prolapse (MVP). By and large, this isn't something I'd do much about. An estimated 1 person in 10 has MVP, and it's usually not a problem. I would take it seriously, however, in a young individual who also has a history of symptoms—particularly something like passing out during exertion. And an abnormal murmur in the presence of MVP certainly deserves attention.

Should echocardiography and electrocardiography be part of the exam?

I don't think so. They would break the bank, and plenty of studies show that they add confusion and don't contribute much to screening accuracy. The principal rationale for echocardiography is identifying HCM, and this condition is too rare—about 2 in 1,000 young adults—to make it worthwhile routinely. There are groups that claim to do echocardiographic screening very cheaply (5), about $7 per individual, but such charges are possible only with volunteer time and donated equipment.

The same recommendation goes for electrocardiography. Some doctors do advocate it, however, for young athletes who plan to participate in collision sports, to provide a baseline to evaluate possible heart contusions later.

The only time these tests have an unequivocal role is when there are symptoms or findings, such as arrhythmias or murmurs, that require further investigation.

When is referral to a cardiologist indicated?

A referral is indicated in three circumstances:

1. when you detect what truly appears to be a cardiac abnormality, such as a very loud murmur or what looks like Marfan syndrome;
2. when there are symptoms that worry you, like a history of fatigability or exercise syncope;
3. when you're uncertain about the meaning of a murmur or other finding.

A referral might also be a good idea if the family is concerned and anxious. Even if you know that nothing's wrong, a cardiologist might help allay their fears.

If at all possible, I would refer patients to a cardiologist who has substantial experience in working with athletes. He or she will be savvy about what causes death during exercise, more attuned to how a healthy athlete's cardiovascular system may differ from the unathletic norm, and less likely to exclude an athlete from participation or worry the family unnecessarily.

Best of all, I think, is a cardiologist who has some athletic background himself or herself. Such a person will be more sensitive to the pressures that a young athlete faces.

What would you recommend for an athlete who has a fever?

I wouldn't let an individual with a viral infection accompanied by muscle aches participate because of the risk of viral myocarditis. But this is transient—fever shouldn't disqualify the athlete after it resolves.

How does the exam differ for an older athlete?

For the person over 30, coronary heart disease is the issue (6,7). But the actual risk of myocardial infarction and sudden death during exercise is extremely low, so I'd suggest a stress test only in the presence of symptoms or a lot of risk factors—or if the person is apprehensive and insists on it. I don't think stress testing should be routine.

Among previously healthy people, the degree of coronary narrowing, for that matter, is not always related to the risk of sudden death. What kills is rapid progression of plaque. The most effective use of time and money is a careful explanation of what heart disease feels like.

I'd tell the older athlete to be alert to unusual discomfort during exercise. Not just pain, and not just in the chest—it could be experienced in the jaw, arms, or wrist. This includes "heartburn" during exertion. If such discomfort occurs, he or she should suspend exercise until speaking to you.

Also, be alert to the signs of aortic stenosis noted above—this condition can kill at any age. And I wouldn't want someone of age 30 or 40 with HCM to engage in strenuous exercise, especially if the septum is quite thick—more than 15 or 16 mm. (I would allow downhill skiing for patients in this age-group who have HCM.) But I worry much less about HCM in 50-year-olds—if they've made it that far, they're probably survivors.

References

1. Van Camp SP, Bloor CM, Mueller FO, et al: Nontraumatic sports death in high school and college athletes. Med Sci Sports Exerc 1995;27(5):641-647
2. Thompson PD: Cardiac evaluation of the young or old, competitive or recreational athlete, in Strauss RH (ed): Sports Medicine, ed 2. Philadelphia, WB Saunders Co, 1991, pp 3-19
3. Fahrenbach MC, Thompson PD: The preparticipation sports examination: cardiovascular considerations for screening. Cardiology Clinics 1992;10(2):319-328
4. Feinstein RA, Colvin E, Oh MK: Echocardiographic screening as part of a preparticipation examination. Clin J Sports Med 1993;3(3):149-152
5. Weidenbener EJ, Krauss MD, Waller BF, et al: Incorporation of screening echocardiography in the preparticipation exam. Clin J Sports Med 1995;5(2):86-89
6. Siscovick DS, Weiss NS, Fletcher RH, et al: The incidence of primary cardiac arrest during vigorous exercise. N Engl J Med 1984;311(14):874-877
7. Thompson PD, Funk EJ, Carleton RA, et al: Incidence of death during jogging in Rhode Island from 1975 through 1980. JAMA 1982;247(18):2535-2538

Dr Thompson is the director of preventive cardiology in the Division of Cardiology at the University of Pittsburgh Medical Center in Pittsburgh. He is an editorial board member of The Physician and Sportsmedicine. Mr Sherman is a New York City freelance writer. Address correspondence to Paul D. Thompson, MD, 1212 Kaufmann Bldg, 200 Lothrop St, Pittsburgh, PA 15213-2582.

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