[Blood flow analysis with pulsed echo Doppler cardiography in valvular pulmonary stenosis (author's transl)].

Blood flows in the main pulmonary artery, right pulmonary artery and right ventricular outflow tract were analyzed in 11 cases of valvular pulmonary stenosis and 10 healthy subjects by pulsed echo Doppler cardiography (two-dimensional) with the parasternal and suprasternal approaches. 1) The systolic flow in the right pulmonary artery was detected in 7 cases of valvular pulmonary stenosis, in which the flow of both right and main pulmonary arteries was detected in only one case. The flows seemed to be turbulent. These abnormal signals were never detected in healthy subjects and considered to be caused by the narrowing of the pulmonic orifice. 2) Abnormal flow signals were also detected in the right ventricular outflow tract in patients of pulmonary stenosis. Their features were as follows: (1) A systolic turbulent flow was detected in a case with severe hypertrophy of the wall and narrowing of the lumen of the right ventricular outflow tract. (2) A/S ratio, which is a ratio of the peak velocity in atrial contraction (A) to the peak velocity in systole (S), was larger in cases with pulmonary stenosis than in healthy subjects (p less than 0.05). It was considered that the atrial component in the right ventricular filling was augmented in pulmonary stenosis. (3) The PEP/ET (pre-ejection period/ejection time) of the right ventricle was smaller in cases with pulmonary stenosis than in healthy subjects (p less than 0.05). The ratio exhibited a reverse correlation with the pressure gradient between the right ventricle and pulmonary artery (r = 0.74, p less than 0.025). (4) Acceleration time index, a ratio of the time interval between the upstroke and the peak velocity of ejection flow to the ejection time, as a parameter indicating the time delay of the peak velocity exhibited a significant correlation with the pressure gradient between the right ventricle and pulmonary artery (r = 0.67, p less than 0.05). (5) No correspondence was revealed between the time interval of Q-peak velocity in systole and that of Q-peak intensity of the murmur during systole. It was remained to be clarified.