Today Doppler echocardiography is a reliable noninvasive method in the diagnostic of pulmonary hypertension. We investigated 52 patients (age 1 to 19 years) with pulsed- or continuous-wave Doppler. Systolic pulmonary artery pressure (SPAP) was calculated about the equation of Akiba using acceleration time, corrected by heart rate. SPAP estimated in this way was less than 20 mmHg in 14% of the patients. 20-39 mmHg in 29%, 40-59 mmHg in 31% and about 60 mmHg in 26%. No correlation was found between age and SPAP and only low correlation between score of Shwachman (r = 0.37) or score of Norman-Crispin and SPAP. Between body fat, calculated from the thickness of skin folds, and SPAP was found a good correlation (r = -0.73, p = 0.01).