松浦 壮平

BACKGROUND: Hybrid aortic arch repair with debranching of the supra-aortic vessels carries a high risk of cerebral infarction and fatal complications associated with side clamping of the ascending aorta. A previous study had reported the "real chimney" technique, a novel method for clamp-free total debranching thoracic endovascular aortic repair with the ascending aortic sleeve banding with dacron. In this study, we aim to build upon this foundation by presenting our experience with the early and midterm outcomes of this technique. METHODS: We retrospectively reviewed the medical records of 61 consecutive older adult patients with aortic arch pathologies and a high risk of open repair who underwent total debranching thoracic endovascular aortic repair using the real chimney technique at our institution between January 2014 and June 2022. This technique was used to anastomose the ascending aorta with the main trunk of the triple-branched prosthetic graft. RESULTS: The mean patient age was 75.1 years, and 54% of patients were transferred from medical facilities with cardiothoracic surgery departments. The comorbidities included chronic obstructive pulmonary disease (49.2%), chronic kidney disease (63.9%), coronary artery disease (27.9%), and history of stroke (31.1%). No 30-day mortality was observed. Complications included postoperative renal failure requiring permanent hemodialysis (4; 6.6%), stroke (modified Rankin scale score: ≥2 in 5; 8.2%), permanent paraplegia (1; 1.6%), and permanent paraparesis (4; 6.6%). The median follow-up period was 40.5±28.5 months. The postoperative survival rates at 5 years were 66.8%. No patients experienced complications associated with the aorta or anastomosis site; only 1 patient required an additional procedure for stenosis of the anastomosis site (midterm). An aneurysmal diameter reduction of ≥3 mm was observed in 37 cases (60.7%), and the mean aneurysmal diameter reduction was 5.3 mm. CONCLUSIONS: The postoperative outcome of total debranching thoracic endovascular aortic arch repair is not only acceptable but also promising, particularly in patients at high risk of open repair. CLINICAL IMPACT: Our novel real chimney technique for total debranching thoracic endovascular aortic repair of aortic arch pathologies in patients who were at a high-risk for open repair resulted in no 30-day mortality and no complications related to the aorta or the real chimney anastomosis site.The real chimney technique is effective for managing aortic arch pathologies and enables less invasive total debranching thoracic endovascular aortic arch repair without the need for extracorporeal circulation and clamping of the ascending aorta.

BACKGROUND: Chronic limb-threatening ischemia (CLTI) is frequently associated with crural artery occlusion. Complete revascularization beyond the diseased crural artery is preferable; however, complete revascularization is challenging in many cases for various reasons. On the other hand, partial reconstruction for inflow disease sometimes leads to complete relief of symptoms. It is not elucidated which patients may recover from CLTI with partial revascularization (PR). Therefore, we aimed to evaluate the factors affecting outcomes after PR. METHODS: We retrospectively reviewed the medical records of patients who underwent first-attempt PR, for CLTI, for limb salvage, in our institution, between April 2012 and December 2020. We divided these 103 cases into 2 groups: the salvage group (who achieved wound healing or relief from rest pain with PR; n = 81) and the nonsalvage group (who ended with major amputation or additional distal revascularization; n = 22). We evaluated the factors affecting the outcome of PR in terms of patient risk, limb severity (Society for Vascular Surgery Lower Extremity Threatened Limb Classification System; wound, ischemia, and foot infection [WIfI] classification), and anatomical pattern (Global Limb Anatomic Staging System; GLASS classification). RESULTS: Although patient risk between the 2 groups was not statistically significant, hypoalbuminemia (< 3.0 mg/dL) was more prevalent in the nonsalvage group without significance (P = 0.068). Regarding limb severity status, there was no significant difference in WIfI grades. Wound grade showed the strongest correlation (P = 0.11) and reduced wound grade suggested future wound healing. In terms of GLASS, infrapopliteal grade was statistically significant (P = 0.033). Upon a multivariate analysis, among infrapopliteal grade, hypoalbuminemia, and wound grade, infrapopliteal grade (P = 0.0096) and hypoalbuminemia (P = 0.2512) revealed significant differences. Wound grade also showed correlation (P = 0.085). CONCLUSIONS: The usefulness of the WIfI classification and GLASS classification to predict wound healing after PR for CLTI was validated.

A prosthetic vascular graft that induces perigraft tissue incorporation may effectively prevent serious sequelae such as seroma formation and infection. Radiation-crosslinked gelatin hydrogel (RXgel) mimics the chemical and physical properties of the in vivo extracellular matrix and may facilitate wound healing by promoting tissue organization. Fibroblasts cultured on RXgel actively migrated into the gel for up to 7 days. RXgels of three different degrees of hardness (Rx[10], soft; Rx[15], middle; Rx[20], hard) were prepared, and small disc-like samples of RXgels were implanted into rats. In vitro and in vivo results indicated that Rx[10] was too soft to coat vascular grafts. Thus, expanded polytetrafluoroethylene (ePTFE) vascular grafts coated with RXgel were developed using Rx[15] and Rx[20] gels, and ring-shaped slices of the graft were implanted into rats. Alpha-smooth muscle actin (αSMA) and type III collagen (Col-III) levels were detected by immunohistochemistry. Immunohistochemical staining for αSMA and Col-III demonstrated that RXgel-coated vascular grafts induced more granulation tissue than non-coated grafts on days 14 and 28 after implantation. RXgel-coated ePTFE vascular grafts may provide a solution for patients by reducing poor perigraft tissue incorporation.

INTRODUCTION: Neurofibromatosis type 1 (NF-1) or von Recklinghausen's disease, an autosomal dominant genetic disorder, is characterized by a café au lait spot and cutaneous neurofibromas. It typically involves the skin, nerves, bones, muscles, and eyes, and occasionally involves vascular complications and can lead to life-threatening hemorrhage. CASE PRESENTATION: We present the case of a 77-year-old female with a posterior tibial artery rupture with NF-1. She presented with sudden right lower leg swelling, pain, paresthesia, and paralysis; computed tomography images revealed popliteal artery aneurysm with surrounding hematoma, expanding from the posterior aspect of the knee to the calf. Diagnosed with compartment syndrome, due to a ruptured right popliteal artery aneurysm, she underwent prosthetic replacement of the popliteal aneurysm. Intraoperatively, the fragility of the popliteal artery was noted, although no perforation site was recognized despite the aneurysm; active bleeding originated from the hematoma between the calf muscles. Intraoperative digital subtraction angiography revealed an extravasation at the branch of the posterior tibial artery that was managed by coil embolization of the posterior tibial artery. CLINICAL DISCUSSION: Although the frequency of NF-1 vasculopathy is unknown, vasculopathy is the second most common cause of mortality in patients with NF-1, after malignancy. The less invasive endovascular approach might be preferable for treating NF-1-related aneurysm. The NF-related vasculopathy lesion sites are diverse, and intraoperative angiography would help confirm the diagnosis. CONCLUSION: NF-1-related vasculopathy may be associated with vascular fragility, and the endovascular approach might be preferable. Endovascular-first approach could have helped in correct diagnosis in the present case.

Objective: We selectively place carotid shunting when ipsilateral mean stump pressure is less than 40 mmHg during carotid endarterectomy (CEA). This study aimed to assess the validity of our selective shunting criterion by 1D-0D hemodynamic simulation technology. Materials and Methods: We retrospectively reviewed 88 patients (95 cases) of CEA and divided them into two groups based on the degree of contralateral internal carotid artery (ICA) stenosis ratio, which was determined as severe when the peak systolic velocity ratio of the ICA to the common carotid artery was ≥4 by carotid duplex ultrasonography. Patients with severe stenosis or occlusion in contralateral ICA were classified as hypoperfusion group, and those without such contralateral ICA obstruction were classified as control group. Results: Perioperatively, the mean carotid stump pressures were 33 mmHg in hypoperfusion group and 46 mmHg in the control group (P=0.006). We simulated changes in carotid stump pressure according to the changes in the contralateral ICA stenosis ratio. 1D-0D simulation indicated a sharp decline in carotid stump pressure when the contralateral stenosis ratio was >50%, while peripheral pressure of the middle cerebral arteries declined sharply at a ≥70% contralateral stenosis ratio. At this ratio, the direction of the ipsilateral cerebral arterial flow became inverted, the carotid stump pressure became dependent on the basilar artery circulation, and the ipsilateral middle cerebral artery became hypoperfused. Conclusion: Our clinical and computer-simulated results confirmed the validation of our carotid shunting criterion and suggested that contralateral ICA stenosis ratio over 70% is a safe indication of selective shunting during CEA.