Patterns of collateral arteries to the spinal cord after thoraco-abdominal aortic aneurysm repair.

OBJECTIVES: Our goal was to evaluate postoperative patterns of collateral arteries to the spinal cord during occlusion of the segmental arteries supplying the artery of Adamkiewicz (AKA). METHODS: Between April 2011 and December 2022, a total of 179 patients underwent thoraco-abdominal aortic aneurysm repair; 141 had an identifiable AKA on preoperative multidetector computed tomography scans, 40 underwent thoraco-abdominal aortic aneurysm replacement (TAAR) and 101 underwent thoracic endovascular aortic repair (TEVAR). New postoperative collateral blood pathways invisible on preoperative contrast-enhanced computed tomography scans were identified in 42 patients (10 patients who had TAAR vs 32 patients who had TEVAR) who underwent preoperative and postoperative multidetector computed tomography scanning for AKA identification. RESULTS: The thoracodorsal and segmental arteries were the main collateral pathways in both groups. Th9-initiated collaterals were the most common. Collaterals from the internal thoracic artery were observed in the TEVAR group but not in the TAAR group. One patient in the TEVAR group experienced postoperative paraparesis, which was not observed in the TAAR group. Postoperative paraplegia was more common in the non-Th9-origin group, but this difference was not significant. CONCLUSIONS: Thoracodorsal and segmental arteries may be important collateral pathways after TEVAR and TAAR. For thoracodorsal arteries, preserving the thoracodorsal muscle during the approach would be crucial; for segmental arteries, minimizing the area to be replaced or covered would be paramount. An AKA not initiated at the Th9 level poses a high risk of postoperative paraplegia.

Diamond-like carbon coating to inner surface of polyurethane tube reduces Staphylococcus aureus bacterial adhesion and biofilm formation.

Staphylococcus aureus is one of the main causative bacteria for polyurethane catheter and artificial graft infection. Recently, we developed a unique technique for coating diamond-like carbon (DLC) inside the luminal resin structure of polyurethane tubes. This study aimed to elucidate the infection-preventing effects of diamond-like carbon (DLC) coating on a polyurethane surface against S. aureus. We applied DLC to polyurethane tubes and rolled polyurethane sheets with our newly developed DLC coating technique for resin tubes. The DLC-coated and uncoated polyurethane surfaces were tested in smoothness, hydrophilicity, zeta-potential, and anti-bacterial properties against S. aureus (biofilm formation and bacterial attachment) by contact with bacterial fluids under static and flow conditions. The DLC-coated polyurethane surface was significantly smoother, more hydrophilic, and had a more negative zeta-potential than did the uncoated polyurethane surface. Upon exposure to bacterial fluid under both static and flow conditions, DLC-coated polyurethane exhibited significantly less biofilm formation than uncoated polyurethane, based on absorbance measurements. In addition, the adherence of S. aureus was significantly lower for DLC-coated polyurethane than for uncoated polyurethane under both conditions, based on scanning electron microscopy. These results show that applying DLC coating to the luminal resin of polyurethane tubes may impart antimicrobial effects against S. aureus to implantable medical polyurethane devices, such as vascular grafts and central venous catheters.

Comprehensive hemocompatibility analysis on the application of diamond-like carbon to ePTFE artificial vascular prosthesis.

The aim of this study was to obtain comprehensive data regarding the hemocompatibility of diamond-like carbon (DLC)-coated expanded polytetrafluoroethylene (ePTFE). DLC increased the hydrophilicity and smoothened the surface and fibrillar structure, respectively, of the ePTFE. DLC-coated ePTFE had more albumin and fibrinogen adsorption and less platelet adhesion than uncoated ePTFE. There were scarce red cell attachments in in vitro human and in vivo animal (rat and swine) whole blood contact tests in both DLC-coated and uncoated ePTFE. DLC-coated ePTFE had a similar but marginally thicker band movement than uncoated-ePTFE with SDS-PAGE after human whole blood contact test. In addition, survival studies of aortic graft replacement in rats (1.5 mm graft) and arteriovenous shunt in goats (4 mm graft) were performed to compare the patency and clot formation between DLC-coated and uncoated ePTFE grafts. Comparable patency was observed in both animal models. However, clots were observed in the luminal surface of the patent 1.5 mm DLC-coated ePTFE grafts, but not in that of uncoated ePTFE grafts. In conclusions, hemocompatibility of DLC-coated ePTFE was high and comparable to that of uncoated ePTFE. However, it failed to improve the hemocompatibility of 1.5 mm ePTFE graft probably because increased fibrinogen adsorption canceled the other beneficial effects of DLC.

[Repair of Type A Aortic Dissection after Thoracic Endovascular Aortic Repair with Open Stent Graft；Report of a Case].

We repot a case of type A aortic dissection after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection. A 70-year-old man underwent TEVAR for type B aortic dissection. Seven months after TEVAR, follow-up computed tomography revealed type A aortic dissection. We urgently performed total arch replacement with open stent graft. Although TEVAR is currently recommended as the 1st-line treatment for complicated type B aortic dissection with malperfusion or dilatation, retrograde type A aortic dissection might occur as a rare but life-threatening complication. Fragility of the aortic wall and disease progression combined with stent grafting-related injury contribute to its occurrence. Open stent graft technique is useful in such a case.