Wednesday, October 04, 2006

Screening Athletes for Sudden Cardiac Death

There are few things that make me more anxious than the evaluation of the competitive athlete for their risk of sudden cardiac death. There have been many instances of famous athletes collapsing on the basketball court or football field – suddenly and unexpectedly. Every one of these tragic events seems to occur with a host of witnesses and often lands on the front page of the local newspaper. The stakes are high for all involved. To deny an athlete the opportunity to play can be catastrophic to the athlete, while permitting an athlete to play and having them die can be equally (if not more) catastrophic to the physician and the surviving family members.

Today a large population-based observational study from Italy regarding the potential benefits of screening athletes for their risk of cardiovascular death was published in the Journal of the American Medical Association. This study compiled the incidence of cardiovascular death in athletic and non-athletic individuals between 12 and 35 years of age between 1979 and 2004 in the Veneto region of Italy. After 1982 all participants in competitive sports were required by Italian law to undergo screening for cardiovascular diseases at risk of sudden death during sports. Their evaluation included a family and personal history, physical examination and electrocardiogram (ECG). The findings of the large study demonstrated that there were 55 deaths in the screened athletes compared to 265 deaths in unscreened non-athletes, and the incidence of death decreased from 1 in 27,777 athletes to 1 death in 250,000 athletes over the period studied, an 89% reduction. The presence of an ECG in the screening criteria differs from the current recommendations by the American Heart Association, but is in line with the recommendations of the Sports Cardiology Study Group of the European Society of Cardiology.

Now before leaping to conclusions, there were some significant limitations to this study, many of which were nicely outlined by Paul Thompson, MD and Benjamin Levine, MD in their accompanying editorial published in the same issue. They include:
  • The study was not a controlled comparison of the screening versus non-screening of athletes, but rather a population-based observational study.

  • The study did not evaluate the routine use of ECGs compared with more limited screening based on just history and physical examination.

  • There are differences in disease prevalence in Italy versus the US: hypertrophic cardiomyopathy is more common in the US whereas arrhythmogenic right ventricular dysplasia is more common in Italy.

  • The annual death rate of 1:27,000 athletes at the initiation of the study is high compared to other studies, an this initial death rate accounts for much of the reduction seen over the course of the study,

  • The lowest death rate reported in this study was 0.4 deaths per 100,000 person-years, and is similar to the 0.44 per 100,000 person-years reported for US high school and college students in the US between 1983 and 1993.

  • women were underrepresented in this study
Finally, while there is enthusiasm for screening amongst the public and individuals who stand to make money from this screening (who, me?), there is certainly a potential risk that any well-intentioned screening process will have risks inherent to more invasive evaluations that might be required in athletes whom screen “positive.”

But one thing seems clear to me. An ECG is a remarkably simple and non-invasive test to evaluate the heart. Right ventricular abnormalities, chamber enlargement or ventricular hypertrophy, abnormal electrical pathways (Wolff-Parkinson-White syndrome), repolarization abnormalities (congenital Long QT Syndrome) and arrhythmias can be readily detected. Physical examination often cannot detect these subtle killers. And while this study is not conclusive and has significant limitations, it serves as the most potent longitudinal study to date of the value of screening to prevent death in our young athletes.

The addition of the ECG to screening of athletes, given this study’s data, should be seriously considered. For a small cost, It might just save a young athlete’s life and keep me off the front page of the Chicago Tribune.

-Wes

2 comments:

Anonymous said...

I have just been diagnosed with a long QT -still undergoing tests to see if it is LQTS when I passed out 200 yards from the finish of a full distance triathlon (2 weeks ago).
your post struck me because I am 27 years old, and have been a competitive swimmer since I was 7 (D1, Olympic trials qualifier).

Other than passing out from dehydration and exhaustion in the triathlon I have never had any symptoms of LQTS nor has my family. The only red flag is that my LQ interval increased to 480 (normal for me is 420 with resting HR of low 50s).

It is very difficult for me to understand going from perfectly healthy to being told that I shouldn't compete in sports when I still feel fine. Competing is what I do, it is what defines me as a person, so your comment:
"To deny an athlete the opportunity to play can be catastrophic to the athlete, while permitting an athlete to play and having them die can be equally (if not more) catastrophic to the physician and the surviving family members."
really struck me. How do we know if it is safe or not to continue to compete? Can we just take the risk...if lifestyle modification is not an option (as in the case with Olympic swimmer Dana Vollmer)?

mfgriffis@aol.com

DrWes said...

Anony-

Thanks for your comments. It is these difficult decisions that make sports medicine evaluations so difficult - it's the old "damned if you do and damned if you don't" conundrum we face each time situations like yours surface.

While we understand the POTENTIAL risks inherent to different cardiovascular screening findings - none of us has a crystal ball that can predict the actual eventual outcome for any individual patient's circumstances. Seek counsel from your doctor, seek several opinions (if needed), and ultimately you'll have to weight the options based on the data and recommendations you receive.

Best of luck -

DrWes