Balloon Atrial Septostomy (BAS)

• Several experimental and clinical observations suggest that an atrial defect may be of benefit in the setting of pulmonary hypertension (PH) as it would allow right to left shunting which increases systemic output
  
  • This would increase systemic arterial oxygen saturation
  • It also decompresses the right atrium and ventricle therefore decreasing signs and symptoms of right heart failure

• At present, indications for BAS are:
  
  • Patients who are in World Health Organization functional class (WHO FC) IV with severe syncope and/or right heart failure despite all available medical treatments
  • Palliative bridge to lung transplantation
  • Sole treatment modality when other options are not available
  • Considered in pulmonary arterial hypertension (PAH) associated with surgically corrected congenital hear disease (CHD), connective tissue disease, distal chronic thromboembolic pulmonary hypertension (CTEPH), pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis
  • May be considered before severe hemodynamic compromise and end-organ dysfunction occur

• Should be performed only at institutions with significant procedural and clinical experience
• Avoided in patients with a baseline mean right atrial pressure (RAP) >20 mmHg and O₂ saturation at rest of <85% on room air

Transplantation

• There is no agreement on the optimal type of transplantation for patients with PAH, whether single lung, double lung or combined heart and lung
• Indicated in PAH patients when they have an unacceptable response to PAH therapies seen in FC III or IV
• Due to lack of effective medical therapeutic regimen, patients with pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis should be candidates for transplantation at diagnosis
• Overall 5-year survival rates in PAH patients following transplant have been recorded at 45-50% and are continually increasing
  • Recent records showed 52-75% at 5 years and 45-66% at 10 years