Background:We assessed whether measuring pulmonary annular motion velocity could serve as a novel method of evaluating right ventricular outflow tract (RVOT) performance in pediatric patients with heart disease.Methods and Results:Tissue Doppler-derived pulmonary annular motion velocity was determined from the parasternal long-axis view of the RVOT. Pulmonary annular velocity was measured in children (age, 5–10 years) with an atrial septal defect (ASD), pulmonary arterial hypertension (PAH), surgically repaired tetralogy of Fallot (TOF) and healthy children (control). Pulmonary annular velocity waveforms comprised systolic bimodal (s1’ and s2’) and diastolic e’ and a’ waves in all groups. The peak velocity of s1’ and s2’ was significantly higher in the ASD group than in the controls (15.0±2.4 vs. 11.2±2.1 and 6.0±0.9 vs. 4.4±1.2 cm/s; P<0.01 and P<0.001, respectively). The s1’ and s2’ peak velocities were significantly lower in the PAH group (8.5±1.2 and 3.2±0.4 cm/s; P<0.05 for both), and in the group with TOF (5.3±2.2 and 3.4±1.4 cm/s; P<0.001 and P<0.05, respectively). The peak velocity of e’ was significantly decreased in the PAH and TOF, compared with the control group (6.8±1.6 and 8.2±2.9 vs. 11.9±1.9 cm/s; P<0.001 for both).Conclusions:Pulmonary annular motion velocity determined using tissue Doppler imaging is a promising method of assessing RVOT function. (Circ J 2016; 80: 168–176)