Persistent left cranial vena cava and right cranial vena cava aplasia in a French bulldog and a Cavalier King Charles spaniel with severe pulmonic stenosis.

One French bulldog and one Cavalier King Charles spaniel were referred for pulmonary balloon valvuloplasty (PBV) after being diagnosed with severe pulmonic stenosis. In both patients, a dilated coronary sinus was noted on transthoracic echocardiography, suggesting persistent left cranial vena cava. Despite complete preoperative workup being performed, persistent left cranial vena cava with right cranial vena cava aplasia was not identified until after right jugular catheterization.