Up For a Challenge? Read the ECGs of Children Athletes

Interview | At the 3RD ACC Sports Cardiology Summit in Indianapolis, CardioSource WorldNews: Interventions spoke with Sanjay Sharma, MD, a professor of inherited cardiac diseases and sports cardiology at St. George’s University of London. In this interview, Dr. Sharma focuses on the particular challenges of reading the ECGs of athletes and particularly child athletes.

CSWN: How do you deal with an athlete’s ECG?

SANJAY SHARMA, MD: The athlete’s ECG is divided into two main categories: one that reflects increased vagal tone, and the other that reflects increased chamber enlargement. We know that about 80% of athletes would have an ECG that falls into one or both of those categories. These changes include sinus bradycardia, sinus arrhythmia, first-degree AV block, voltage criteria for left ventricular hypertrophy, the early repolarization pattern, and incomplete right bundle branch block. I should state that these are normal changes. However, many athletes also express very profound repolarization changes that may overlap with disease processes. The current criteria for ECG interpretation are relatively conservative, and many athletes end up having false-positive tests. That’s the Achilles’ heel of the ECG.

Now, you are working on some new, updated guidelines in Europe, correct?

Yes, we are. We are actually in the process now of revising the 2010 ESE recommendations. It’s been 5 years since we wrote them, and there has been a lot of science since then. There are certain anomalies that we used to consider as abnormal that we would now regard as normal variants. These include the presence of an isolated left axis deviation or right axis deviation, voltage criteria for right or left atrial enlargement, and voltage criteria for right ventricular hypertrophy. If these are found alone or in existence with other so-called “Group 1” exercise stress echocardiography changes, we would consider them as normal if the athlete is asymptomatic, if nothing is found on physical examination, and if there is no family history of a sinister hereditary cardiac condition.

We must also take into account ethnicity, because athletes of African-American or Afro-Caribbean origin make up a very large proportion of athletes in the United States and also in many European countries, such as the United Kingdom and France. These individuals do exhibit very profound repolarization changes characterized by convex ST segment elevation and asymmetric deep T-wave inversion in leads V1 to V4. Our studies have shown that these are normal variants and would not require further assessment in most athletes.

What ages are we talking about? With kids getting involved at a younger and younger ages, does that make a difference as to how you’re looking at the ECG?

That’s a good question. I think more work needs to be done on ECG of pediatric athletes. There are not enough data there. We need to provide some prospective assessments, but the data that I’m alluding to is confined to athletes who are aged between 14 and 18 years when we’re talking about young people. We extend this up to 35 years old. You may wonder why we’ve started at the age of 14 years, and this is because most individuals by the age of 14 are in puberty. Hypertrophic cardiomyopathy (which is the most common cause of sudden cardiac death in athletes) doesn’t usually show itself until puberty, so if we start before that, we may miss it.

The second point is that people who are aged 14 or less express T-wave inversion in leads V1 to V3, which overlaps with the diagnosis of arrhythmogenic right ventricular cardiomyopathy. However, after the age of 14, only 1% or 2% of individuals express this ECG change, so I think 14 is a reasonable age to start.

We’ve taken some hits from critics across the pond in terms of how we do pre-participation screening and examinations. Today you talked a little bit about how you do it over in Europe. Are we as far behind as we sometimes are criticized for being?

Let’s start by saying that there are two screening models which are supposed to be cost-effective or relatively cheap: the American model (which relies on history and examination), and the Italian (and now European) model, which relies on history, examination, and the inclusion of a 12-lead ECG. It’s not surprising that the inclusion of a cardiac test will improve detection rate. There is no doubt about it. Therefore, you’re more likely to identify more athletes with disease when you include the ECG versus not including it.

There are issues. Firstly, the ECG has a very high false-positive rate, and many countries do not have an infrastructure for cardiovascular screening. In fact, there are only three countries that actually screen all their athletes: the United States, Italy, and Israel. No other country in Europe actually performs screening at mass level. In countries such as the United Kingdom, France, and Spain, screening is confined to the highest echelons of sports and the most elite athletes. The high school kid doesn’t get screened.

Keywords: CardioSource WorldNews Interventions

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