Parents who have been to the doctor’s office will know that the doctor will sometimes say that the child now has pulmonary hypertension after looking at the ultrasound, but the ultrasound doctor may not mark pulmonary hypertension underneath. How can we determine the presence of pulmonary hypertension based on a cardiac ultrasound? Pulmonary hypertension should be considered when one of the following three conditions is met: 1. pulmonary regurgitation velocity >3m/s 2. pulmonary regurgitation velocity >3m/s 3. children with ventricular septal defect, shunt velocity <3m/s at the defect site (the above conditions are not absolute and need to be analyzed for specific problems)