Transcatheter creation of a Potts shunt with the Occlutech Atrial Flow Regulator: Feasibility in a pig model

Background: Creation of a Potts shunt, a connection between the left pulmonary artery (LPA) and descending aorta (DAo), improves functional status and survival in drug-refractory suprasystemic pulmonary arterial hypertension. We investigated a new approach to transcatheter Potts shunt creation in pigs.

Methods and results: In six pigs, a steerable SureFlex sheath was used to optimize the trajectory of perforation from the DAo into LPA using a 0.035″ radiofrequency wire. The combination of a larger perforation, stiffer radiofrequency wire and smooth dilator-to-sheath transition allowed sheath entry into the LPA without requiring an arterio-venous wire circuit. The Occlutech Atrial Flow Regulator (AFR), a double-disc device with a central fenestration, was deployed through this sheath with apposition of the distal disc to the posterior LPA wall and the proximal disc to the anterior DAo wall. The AFR is compliant and crumpling of the central fenestration was resolved by balloon dilation. It was feasible to implant a stent within the fenestration (n = 3). Aortography confirmed a left-to-right shunt through the AFR without contrast extravasation. Autopsy demonstrated anchoring of both discs against the vessel walls, patency of the fenestration and secure placement of the stent with no intra-thoracic bleeding.

Conclusions: In an acute pig model, we have demonstrated the feasibility of creating a transcatheter Potts shunt with a simplified technique using a steerable sheath, a double-disc device with a central fenestration that acts as the shunt channel and optional stenting of the fenestration.