Common complications after surgery for transposition of the great arteries (TGA) include systemic ventricular dysfunction and arrhythmia after atrial baffle (AB) repair and outflow tract stenosis or regurgitation after the arterial switch (AS).Severe pulmonary hypertension (PHT) is a rarely reported problem after AB and AS. We report three cases of PHT from our Adult Congenital Heart Clinic, two after AB and one after AS.

We currently follow 78 patients with repaired TGA; 70 had atrial and 8 had arterial switch procedures. Two patients with AB have developed severe pulmonary hypertension. One presented at age 27 and pulmonary artery pressure was 105/65mmHg at cardiac catheterization. She had simple TGA with Mustard repair at age 5 months. Two years after the diagnosis of PHT, she remains functionally impaired on Bosentan and Sildenafil. Another patient presented at age 34 years with suprasystemic pulmonary hypertension late after repair. She was born with complex TGA and had had AB and VSD closure at 8 months. Despite Bosentan, Sildenafil and inotropic support, she died four months after the diagnosis had been made, awaiting heart/lung transplantation. Finally, a 16-year-old boy presented with suprasystemic pulmonary pressures after an arterial switch procedure in the neonatal period, for simple TGA. He’s currently on Bosentan therapy with good therapeutic response.

4% of our adult CHD patients with TGA have developed late severe pulmonary hypertension. As novel therapies are available for this complication, regular surveillance and early treatment for this condition should be considered.