Characteristics of Screening Echocardiograms in an Elite American Football Player Population

Abstract

Sports medicine clinicians have long recognized that highly conditioned, strength-trained athletes often present characteristics of “athlete’s heart” that do not conform with standard population measurements from ECG and echocardiogram studies. PURPOSE: To describe the echocardiogram characteristics and the proportion of measurements exceeding established ranges among elite American football players. METHODS: We systematically screened 1319 NFL scouting combine participants from 2011-2014 prior to participation. Each player underwent a resting echocardiogram as part of a thorough physical examination. Wall thickness and chamber size were measured according to American Society of Echocardiography standards. The aortic measurement was taken at the maximal diameter of the visualized ascending aorta in the parasternal long axis view using the “leading edge to leading edge” technique. Measurements were performed off-line by two expert technicians and confirmed by an expert echocardiographer from the Indiana University Health System. RESULTS: On average, players were 22.6 years old (SD= 0.9), 73.8 inches tall (SD=2.7), and weighed 244 pounds (SD=46). 67% were black and 24% were white. The 50th and 95th percentiles for interventricular septum (IVS) thickness were 1.13 and 1.40 cm, respectively; 1.04 and 1.31 cm for left ventricular posterior wall (LVPW) thickness; 2.76 and 3.38 cm for aorta diameter; and 5.15 and 5.92 cm for left ventricular end diastolic diameter (LVEDD). The 50th and 5th percentiles for left ventricular ejection fraction (EF) were 0.59 and 0.51, respectively. The proportion of players with measurements outside of established norms were 56% for IVS, 35% for LVPW, 45% for LVEDD, 2% for aorta, and 1% for EF. CONCLUSIONS: In a large population of elite American football players, conventional standards for left ventricle wall thickness and size were frequently exceeded, while those for ejection fraction and aorta diameter were not.