Patent Ductus Arteriosus In Tetralogy Of Fallot

Patent ductus arteriosus in Tetralogy of Fallot, seen as a mosaic colour jet in pulmonary artery. Colour flow imaging shows high velocity jet in the pulmonary artery arising distally, from the descending aorta, suggesting a patent ductus arteriosus (PDA). This is one of the compensatory mechanisms to improve pulmonary flow in Tetralogy of Fallot. Another mechanism is major aortopulmonary collateral arteries (MAPCA). Intra pulmonary collaterals can also occur in Tetralogy of Fallot. Desc Ao: descending aorta. The image is in the parasternal short axis view. Peaks systolic gradient of the continuous flow is 61.5 mm Hg. That will be the gradient between descending aorta and pulmonary artery.