Markedly abnormal electrocardiograms ECGs in young and apparently healthy athletes may represent the initial expression of underlying cardiomyopathies that may not be evident until many years later and that may ultimately be associated with adverse outcomes, according to the Jan. 10 issue of The New Journal of Medicine.
Young, trained athletes may have abnormal 12-lead ECGs without evidence of structural cardiac disease. Whether such ECG patterns represent the initial expression of underlying cardiac disease with potential long-term adverse consequences remains unresolved.
Antonio Pelliccia, MD, Medical Director of the Institute of Sports Medicine of the Italian National Olympic Committee and Professor of Pathophysiology in Sports Medicine at La Sapienza University of Rome, and colleagues, assessed long-term clinical outcomes in athletes with ECGs characterized by marked repolarization abnormalities.
From the database of the Institute of Sports Medicine and Science in Rome, of 12,550 trained athletes, the researchers identified 81 with diffusely distributed and deeply inverted T waves ( 2 mm in at least three leads) who had no apparent cardiac disease and who had undergone serial clinical, ECG, and echocardiographic studies for a mean of nine years. They reviewed ECG data from the database for all athletes evaluated at the institute between 1979 and 2001. Comparisons were made with 229 matched control athletes with normal ECGs from the same database, according to the authors.
From the database, they identified 123 subjects (1 percent) who presented with marked repolarization abnormalities. Because of further exclusionary criteria, the researchers were left with 81, who had at least two clinical evaluations (with 12-lead ECG and echocardiogram), and therefore they constituted the final study group. The control group included 229 athletes similar in age, sex, and duration of follow-up to the study group.
Of the 81 athletes with abnormal ECGs, 5 (6 percent) ultimately proved to have cardiomyopathies, including one who died suddenly at the age of 24 years from clinically undetected arrhythmogenic right ventricular cardiomyopathy. Of the 80 surviving athletes, clinical and phenotypic features of hypertrophic cardiomyopathy developed in three after 12 years (at the ages of 27, 32, and 50 years), including one who had an aborted cardiac arrest. The fifth athlete demonstrated dilated cardiomyopathy after nine years of follow-up.
In contrast, none of the 229 athletes with normal ECGs had a cardiac event or received a diagnosis of cardiomyopathy nine years after initial evaluation. Only four (2 percent) had evidence of other cardiovascular disorders.
The authors summarized that they investigated the clinical course of trained athletes with marked repolarization abnormalities on the ECG, and though such abnormalities were uncommon, they were associated with a disproportionately increased risk of the subsequent development of structural cardiac disease.
The researchers concluded that athletes with such ECG patterns merit continued clinical surveillance.