Sildenafil therapy in complex pulmonary atresia with pulmonary arterial hypertension

Complex pulmonary atresia (CPA) i.e. pulmonary atresia with ventricular septal defect and major aorto-pulmonary collaterals (MAPCAs) or Tetralogy of Fallot with MAPCAs frequently have a clinical course complicated by development of pulmonary arterial (PA) hypertension.

A cross-sectional retrospective review of patients >16 years with CPA or Tetralogy of Fallot with MAPCAs and PA hypertension treated with sildenafil was conducted. Case notes were reviewed for baseline and follow-up (after sildenafil) characteristics.

Five patients, 4 female, median age 28 (range 18 to 47) years, were identified. All patients experienced symptomatic improvement: 2 of 4 wheelchair bound patients responded dramatically and walked 345 and 157 m respectively in 6 min following sildenafil therapy. One of the 4 with marked PA arborization abnormalities and severe ventricular dysfunction had initial symptomatic improvement. Another patient improved from walking less 100 m to climbing 2 flights of stairs. Arterial saturations improved in 2 cases from 70 and 60% to 87 and 84% respectively, whilst arterial saturations remained static in 1 case despite embolization of a classical Blalock-Taussig shunt. One patient with PA arborization/diminished PA bed was unable to tolerate sildenafil.

Sildenafil is well tolerated and leads to symptomatic improvement and better saturations in the majority of patients with CPA with PA hypertension when used in isolation or as an adjunct to percutaneous PA angioplasty.