Electrocardiography and Echocardiography Findings in Contemporary Dancers

Abstract

Alterations in cardiac structure and function as a result of chronic training have been extensively reported in the literature. To date, there is limited data on dancers. This study attempts to define cardiac electrical, structural, and functional characteristics of the heart in female contemporary dancers. Forty-four female full-time contemporary dance students (age: 23.0 ± 5.6 years, height: 165.2 ± 7.9 cm, body mass: 59.2 ± 7.2 kg) volunteered for the study and underwent 12-lead electrocardiography and twodimensional echocardiography. Echocardiographic results were compared with 30 age-matched and gendermatched controls. Sixteen percent (7/ 44) of dancers presented with sinus bradycardia (< 60 bpm) and seven percent (3/44) demonstrated shortened PR intervals (< 120 ms). Sokolow voltage criteria for left ventricular hypertrophy was observed in only 4% (2/44). Fourteen percent of dancers (6/44) demonstrated right axis deviation and nine percent (4/44) had incomplete right bundle branch block. One dancer exhibited nodal rhythm. Minor ST segment elevation (< 0.2 mV) was present in 7% (3/ 44) of dancers, and equally minor ST segment depression (£ 0.2 mV) was present in 7% (3/44). Negative T waves and large T waves (>1.0mV) were observed in 14% (6/44) and 4% (2/44) of the dancers respectively. QRS and QT duration were within normal limits for all dancers. Echocardiography revealed no significant differences between dancers and controls for all structural and functional indices. It is concluded that contemporary dancers demonstrate limited cardiac structure and function changes compared to matched controls.