Complete Antegrade Transapical Deployment of a Branched Aortic Arch Endograft: A Porcine Feasibility Study

Purpose: To describe and prove the concept of a technique for complete transapical deployment of a single-branch aortic arch endograft in a porcine model. Methods: Eight domestic pigs underwent antegrade transapical delivery of a single-branch arch endograft, including a mating stent-graft to the innominate artery. Technical feasibility, operating time, radiation parameters, and hemodynamic changes were studied according to a standardized protocol during baseline (T0), after establishing the transapical access and through-and-through wire (T1), and after stent-graft deployment (T2). Myocardial and cerebral blood flow status was assessed using fluorescent microspheres (FM) and transit-time flow measurement (TTFM) monitoring. Results: Transapical access, introduction and deployment of the endograft, side branch catheterization, and deployment of the mating stent-graft were feasible in 6 of 8 animals. One animal died due to irreversible heart rhythm disorders and one due to accidental graft rotation during deployment, resulting in unintended coverage of the innominate artery. The mean operating and fluoroscopy times were 223 +/- 11 minutes and 27.2 +/- 6.3 minutes, respectively. During introduction and deployment of the stent-graft, transient aortic valve insufficiency occurred in all animals. Hemodynamic stability recovered within 10 minutes after retrieval of the delivery system in all animals. The innominate artery was patent, with unchanged TTFM measurements throughout the procedure. FM evaluation revealed stable cerebral blood flow. Conclusion: An antegrade transapical access to the aortic arch for implantation of a single-branch endograft is feasible in a porcine model with reversible impact on hemodynamic measures during deployment. Transapical access allows deployment of a complex endograft through a single large-bore access site in a porcine model.