Anomalous Left-to-Right Shunting Vessel between the Ascending Aorta and Right Pulmonary Artery and Concurrent Left Peripheral Pulmonary Artery Stenosis in a Dog.

• Atypical appearance of continuous shunting vessel warrants further characterization. • A type III PFAA has not been previously suspected in dogs. • Unilateral pulmonary artery stenosis may not impose significant pressure overload.