Perforating the GORE® CARDIOFORM Septal Occluder and Atrial Septal Defect Occluder to Gain Access to the Left Atrium

Background:
Percutaneous transseptal access to the left atrium is necessary for many structural and electrophysiologic procedures. The potential need to access the left atrium may influence decision making for patent foramen ovale or atrial septal defect closure. To date, the ability to cross the expanded polytetrafluoroethylene (ePFTE) membrane of the GORE® CARDIOFORM Septal Occluder (GSO) and GORE® CARDIOFORM ASD Occluder (GCA) after implantation has yet to be evaluated.

Methods:
Sixteen canines underwent implantation of a GSO (8) or GCA (8) device and were maintained on anti-platelet therapy. A transseptal crossing procedure was performed through the device 85 (±1) days post occluder implantation. Two physicians individually performed equal numbers of the crossing procedure utilizing commercially available equipment: either an 18 gauge Cook Transseptal Needle via a Mullin’s introducer sheath (4/8 GSO, 4/8 GCA) or a Baylis Medical Radiofrequency NRG® C1-shape Transseptal Needle via a Baylis Medical SureFlex steerable introducer sheath (4/8 GSO, 4/8 GCA). The crossing site was dilated via a combination of a high-pressure coronary balloon and/or a cutting balloon with subsequent advancement of a 12 French Mullin’s sheath into the left atrium.

Results:
Left atrial access was achieved in all cases with no intraprocedural complications or deaths. Post-mortem data demonstrated passage through both occluder discs in all radiofrequency/SureFlex sheath cases (4 GSO, 4 GCA) and half of the standard needle/Mullin’s sheath cases (3 GSO, 1 GCA). The remaining standard needle/Mullin’s sheath cases (1/8 GSO, 3/8 GCA) demonstrated passage of the needle into the left atrium through the right atrial disc but around the septal aspect of the left atrial disc, therefore not perforating the left atrial disc.

Conclusions:
Left atrial access may be achieved through the GSO or GCA devices after implantation and endothelialization. The combination of a radiofrequency needle with steerable sheath provides benefit over a standard needle/Mullin’s sheath in accomplishing passage through both occluder discs.