Atrioventricular plane displacement in female endurance athletes

Introduction: A novel hypothesis for increased ventricular pumping describe s the heart as a displacement pump, in which atrioventricular plane displac ement (AVPD) is an important mechanism. The hypothesis predicts that AVPD i ncreases at high heart rates. The aim of the present study was to determine whether AVPD increases during exercise at high heart rates. A secondary ai m was to study the left ventricular function and dimensions in endurance-tr ained young female athletes. Methods: Eight female cross-country skiers (18 .5 +/- 0.9 yr, 169.3 +/- 2.9 cm, 55.7 +/- 4.2 kg, and 64.8 +/- 3.7 mL(.)kg( -1.)min(-1) in maximal oxygen uptake) were compared with seven sedentary fe male controls (18.0 +/- 0.6 yr, 175.0 +/- 2.5 cm, 71.1 +/- 4.1 kg, and 42.8 +/- 3.0 mL(.)kg(-1.)min(-1) in maximal oxygen uptake). Cardiac anatomy and function were assessed by echocardiography. Results: Whereas left ventricu lar ejection fraction (LVEF) increased in both groups, AVPD fell significan tly during exercise. AVPD did not correlate with LVEF, and there were no di fferences in AVPD between groups either at rest or during exercise. Cardiac output index (mL(.)lean body mass(-0.67)) and stroke volume index (mL(.)le an body mass(-1)) were higher in the trained group. The trained group had a larger left ventricular mass, and left ventricular internal dimensions, sc aled to lean body mass. Conclusions: This first study to examine AVPD at re st and during exercise in endurance-trained athletes did not indicate that AVPD is an important mechanism of increased cardiac pumping during exercise . Endurance-trained female athletes have larger left ventricular dimensions and increased function as compared with sedentary subjects.