ECG youth screening identified potential risk for sudden cardiac death

Marek J. Heart Rhythm. 2011;8:1555-1559.

Electrocardiograms may help prevent sudden cardiac death in US high school students, data from a recent study showed.

Through the Young Hearts for Life screening program, 32,561 high school students in suburban Chicago (51% boys; mean age, 16 years) participated in ECG screenings between September 2006 and May 2009. Abnormal and unacceptable ECGs were determined and required further evaluation. To complete the study on a large scale, community volunteers participated in a controlled training program.

Joseph Marek, MD, of the Midwest Heart Foundation, and colleagues found that 2.5% (n=817) of participants had abnormal ECGs, 66% occurring in boys. Specifically, left ventricular hypertrophy was found in 141 participants, which may be associated with hypertrophic cardiomyopathy. In addition, 100 participants had prolonged QTc, which may indicate long QT syndrome. The researchers determined that 0.81% of ECGs were technically inadequate and required repeat ECGs on the same day.

“One of the main arguments against ECG screening is that the rate of abnormal ECGs will be unmanageably high; one prior study reported a frequency of 40%,” researchers wrote. “It is feared that this could drain the resources of the medical community and not meet reasonable cost-effectiveness criteria demanded of a screening program.”

Along with differences in ECG frequency rates, researchers found a lower prevalence of LV hypertrophy and abnormal ST-T wave changes in the current study vs. rates reported in an Italian registry with average follow-up of 26 years. Researchers said these differences in results are caused by differences in study population. Previous studies focused on a population that represents “a small proportion of the total population of youths in the community at risk for sudden cardiac death,” such as elite athletes who have a higher prevalence of abnormal ECG findings.

“Prior studies defined abnormal ECGs by criteria that included physiologic changes that are not associated with SCD,” researchers wrote. “Our study addresses these issues by shifting the focus from identifying all ECG abnormalities to identifying only ECGs with findings suggestive of disorders associated with sudden cardiac death.”

Disclosure: Dr. Marek reports no relevant financial disclosures.

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