Emergency use of Physician-modified Fenestrated Endograft in a Symptomatic Patient Who was Waiting for a Manufactured Graft to Treat Chronic Post-dissection Thoracoabdominal Aneurysm

Abstract

Introduction - Fenestrated-branched endovascular repair (F-BEVAR) using custom manufactured devices (CMDs) has been applied to treat post-dissection thoracoabdominal aortic aneurysms (TAAA), but the long wait period for device manufacturing limits its application in patients with symptomatic or contained ruptured aneurysms. Methods - A 59-year-old female patient who was waiting for CMD (Cook Medical, Brisbane, Australia) presented with a symptomatic post-dissection TAAA. The patient had undergone a successful first stage thoracic endovascular repair with creation of a fenestration in the distal aortic septum to perfuse the right kidney, which originated from the false lumen. Repeat computed tomography angiography revealed compression of the true lumen below the level of the fenestration with pressurization of the false lumen (Figure A). The patient was treated emergently using a physician-modified endovascular graft (PMEG) with four fenestrations and preloaded guidewires. The technique of PMEG using low-profile Zenith Alpha™ Thoracic stent graft (Cook Medical, Copenhagen Denmark) is presented with video and illustrations. Results - The thoracic stent-graft was modified onsite under strict sterile technique using the same measurements obtained for the original CMD request. The active fixation bards were removed to facilitate re-sheathing. Four fenestrations were created with ophthalmologic cautery and reinforced using a double layer of nitinol wire (Figure B). Radiopaque markers were added for orientation. Four 0.014-inch preloaded guidewires were added exiting via the top of the delivery system (Figure C). Diameter-reducing sutures were applied and the device was reintroduced into the original 18Fr sheath. Using bilateral femoral and right brachial approach, a long 5Fr sheath was introduced via the brachial approach exiting via the femoral approach. The PMEG was loaded into a through-and-through wire, while the four preloaded guidewires were loaded into a long 5Fr brachial sheath. The device and sheath were advanced into position and deployed in a stepwise fashion allowing sequential catheterization of the celiac axis, superior mesenteric artery and both renal arteries in the compressed true lumen (Figure D). Once all vessels were catheterized, the bifurcated device and iliac limbs were added and flow was restored to the lower extremities. Sequential renal-mesenteric stenting was done. A completion cone beam computed tomography revealed successful aneurysm exclusion. The repair was completed with a total endovascular time of 133 minutes and the patient was dismissed on postoperative day 10. Follow-up CTA showed patent stent-graft with type 2 endoleak. A total of 6 PMEG repairs with low profile Zenith Alpha™ Thoracic stent grafts were performed at our institution between 2016 and 2018, representing 2% of the 280 patients treated by F-BEVAR during this period. All six patients who had PMEGs did not meet inclusion criteria for an ongoing prospective study using CMDs Conclusion - PMEGs remain a valuable option to treat TAAAs, including chronic post-dissection aneurysms, in patients with symptoms or contained rupture who are not ideally suited for off-the-shelf devices. Compared to tighter stainless-steel Z stents, the widely spaced nitinol stents of the Zenith Alpha™ Thoracic endograft offer more space for fenestration placement.