Catheter-Based Therapies for Patients With Medication-Refractory Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a disease of progressive distal pulmonary artery remodeling that leads to increased pulmonary vascular resistance, right ventricular failure, and premature death. The diagnosis of PAH is made by right heart catheterization when the mean pulmonary artery pressure is ≥25 mm Hg at rest with a pulmonary vascular resistance of >3 Wood units and a pulmonary capillary wedge pressure of 20 mm Hg or the cardiac index is <2.0 L/min per m2, both indicators of a poor prognosis.4 For these patients, there are several invasive strategies, such as atrial septostomy, a Potts shunt, and pulmonary artery denervation that have a therapeutic or palliative role in the management of PAH and are transitioning from surgical to catheter-based interventional procedures.See Article by Chen et al See Article by Rothman et al Atrial septostomy, a procedure that creates an interatrial right-to-left shunt, is typically reserved for drug-refractory patients with right ventricular (RV) failure and syncope. Atrial septostomy unloads the RV, augments left ventricular preload and, thereby, increases cardiac output.5 The rationale for atrial septostomy is based on the observation that PAH patients with a patent foramen ovale live longer than those without right-to-left shunting and that patients with Eisenmenger syndrome with similar mean pulmonary artery pressures and pulmonary vascular resistance have lower right atrial pressures, less severe RV dysfunction, higher cardiac outputs, and lower mortality rates compared with …