Patent ductus arerious jet in Tetralogy of Fallot on Colour Doppler imaging

Colour flow imaging shows high velocity jet in the pulmonary artery arising distally, form 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 aorto pulmonary 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.

PDA jet in Tetralogy of Fallot

Continuous wave Doppler interrogation of the jet guided by colour flow mapping picks up the continuous flow with a peak gradient of 61.5 mm Hg. The gradient is calculated from the velocity measured by the device using the formula: V = 4 V². Ao: aorta; PA: pulmonary artery

PDA in TOF Video from Cardiophile MD

The video shows the mosaic jet originating from the distal portion of the pulmonary artery from the descending aorta through the PDA.