Effects of isometric stress on left ventricular function assessed by automated border detection technique in athletes

This study assesses left ventricular function before and after isometric stress in a group of 20 athletes compared to 20 volunteers who were used as controls. We performed echocardiographic automated border detection technique during hand grip maintaining 25% maximal force for at least four minutes. Simultaneously, we evaluated Doppler left ventricular filling parameters, such as peak flow velocities in early diastole (E wave, cm s-1) and during atrial systole (A wave, cm s-1) and E/A ratio. From automated border detection waveform we calculated for systolic function: left ventricular end diastolic volumes (mL) and end systolic volumes (mL), ejection fraction (%), and peak ejection rate (s-1). We also calculated for diastolic function peak filling rate (s-1) and time to peak filling rate (ms). Peak ejection rate and peak filling rate were normalized for end diastolic volumes. During hand grip, heart rate and systolic blood pressure significantly increased in both groups. Regarding systolic function, end systolic volumes markedly decreased, and end diastolic volumes with ejection fraction significantly increased. A strong correlation was found between peak ejection rate and ejection fraction (r=0.64, p