Hisashi Uchida

CKD Accelerates Development of Neointimal Hyperplasia in Arteriovenous Fistulas

Arteriovenous (AV) access failure resulting from venous neointimal hyperplasia is a major cause of morbidity in patients with ESRD. To understand the role of chronic kidney disease (CKD) in the development of neointimal hyperplasia, we created AV fistulae (common carotid artery to jugular vein in an end-to-side anastomosis) in mice with or without CKD (renal ablation or sham operation). At 2 and 3 wk after operation, neointimal hyperplasia at the site of the AV anastomosis increased 2-fold in animals with CKD compared with controls, but cellular proliferation in the neointimal hyperplastic lesions did not significantly differ between the groups, suggesting that the enhanced neointimal hyperplasia in the setting of CKD may be secondary to a migratory phenotype of vascular smooth muscle cells (VSMC). In ex vivo migration assays, aortic VSMC harvested from mice with CKD migrated significantly greater than VSMC harvested from control mice. Moreover, animals with CKD had higher serum levels of osteopontin, which stimulates VSMC migration. When we treated animals with bone morphogenic protein-7, which promotes VSMC differentiation, before creation of the AV anastomosis, the effect of CKD on the development of neointimal hyperplasia was eliminated. In summary, CKD accelerates development of neointimal hyperplasia at the anastomotic site of an AV fistula, and administration of bone morphogenic protein-7 neutralizes this effect.

Factors related to postoperative delirium in patients with lower limb ischaemia: a prospective cohort study.

OBJECTIVES To preoperatively determine candidates at definitive risk of postoperative delirium (POD), we identified relevant factors in patients with arteriosclerosis obliterans who underwent bypass surgery. DESIGN A prospective cohort study. PATIENTS AND METHODS 299 patients (age ≥ 60 years) who underwent bypasses in 1995-2006 were enrolled. Cognitive impairment was assessed by the Revised Hasegawa Dementia Scale, the Confusion Assessment Method was also used, and severity was graded as Grade I-III (mild to severe) based on the Delirium Rating Scale. All patients were followed for 3 years. RESULTS POD occurred in 88 patients (29%), with a median age of 75 (10) years (IQR). Onset was 2 (1) days postoperatively, and a duration of 2 (2) days was observed. POD was hyperactive in 89% and was Grade I, II, and III in 11%, 68%, and 21% respectively. Multiple logistic regression analysis identified the following risk factors for POD: age ≥ 72 years (<0.0001), end-stage renal failure (0.001), multiple occlusive lesions (<0.0001), cognitive impairment (0.003), and critical limb ischaemia (0.034). The 3-year survival rate was similar when comparing POD and non-POD patients (84% vs. 88%, NS). CONCLUSIONS This study identified 5 risk factors for POD in patients undergoing bypasses for limb ischaemia. Long-term outcomes were similar when comparing the patients who experienced POD with those who did not.

Combined distal venous arterialization and free flap for patients with extensive tissue loss.

BACKGROUND We evaluated the mid-term outcome of distal venous arterialization (DVA) and the role of a combined free flap as a bridgehead for blood supply. METHODS In the past 5 years, nine patients with extensive tissue loss and lacking graftable distal arteries underwent DVA. These consisted of four primary DVAs, three combined DVA and free flap procedures, and two adjuvant DVAs for hemodynamically failed distal bypasses. After nine primary DVAs, three redo DVAs were performed for early failure. Etiologies were four Buerger disease and five arteriosclerosis obliterans, including three dialysis patients. RESULTS Among the nine DVA cases, there were five primary failures: two underwent amputation, two had successful redo DVA, and the remaining one did not require redo DVA. Primary patency, secondary patency, and limb salvage rates were 44.4%, 55.6%, and 77.8%, respectively. The postoperative period was 1-36 months (median 12). Angiography demonstrated DVA was effective in the early period, and development of collaterals or a capillary network from the free flap replaced the DVA function in the intermediate period. CONCLUSION DVA can be effective as a procedure for limb salvage in patients without graftable distal arteries, and a combined free flap is effective and functions as a bridgehead for blood supply to the ischemic zone.

Clinical Results of Cystic Excision for Popliteal Artery Cystic Adventitial Disease: Long-term Benefits of Preserving the Intact Intima

Surgical treatment for popliteal artery cystic adventitial disease (PACAD) is still controversial. PACAD often occurs in young or middle-aged adults. Therefore, the maintenance of graft patency for very long periods is a concern if a prosthesis is used. Because the intima is intact in PACAD patients with popliteal artery stenosis, a treatment that preserves the healthy intima is ideal. We describe the cases of 3 patients who underwent cystic excision for PACAD with severe stenosis. No recurrence was observed for up to 11 years, and these long-term results revealed that cystic excision could be reconsidered as one of the first-line therapeutic methods.

Large-diameter inferior mesenteric artery in a case involving a ruptured common iliac artery aneurysm

We report a case of a large-diameter inferior mesenteric artery (IMA) that was associated with an occluded superior mesenteric artery (SMA) and a celiac artery (CA) that had significant stenosis in a 79-year-old man with a ruptured right common iliac artery aneurysm. Nonenhanced computed tomography (CT) was performed at another hospital to examine his sudden abdominal pain; it showed the ruptured aneurysm, which prompted us to perform endovascular aneurysm repair (EVAR). CT angiography was performed to accurately evaluate the aneurysm and artery size; it revealed a large-diameter IMA, a highly developed meandering artery to an occluded SMA, and a CA with severe stenosis (A/Cover and B). EVAR was immediately halted because of concerns about intestinal necrosis and a potential severe type II endoleak because of the IMA. The patient was ultimately treated by open surgical repair, in which the aneurysm was replaced with a synthetic graft, and the IMA was anastomosed to the left leg of the Y-graft (C and D). Although the patient developed an intestinal obstruction that persisted for a month, he was discharged 2 months after surgery without the abdominal symptom. He gave informed consent for the publication of this report. A large-diameter IMA is a rare and easily missed cause of vascular insufficiency that can be devastating if it is not recognized before EVAR. Asymptomatic mesenteric arterial stenosis, particularly the combination of SMA and CA stenosis or occlusion, was found in 0.5% of 980 patients who underwent aortography and 1.2% of 553 patients who underwent visceral duplex ultrasound. In patients with an abdominal aortic aneurysm and renal artery stenosis, significant stenosis or occlusion of the CA or SMA was reported in approximately 30% and in <10% of patients, respectively. In addition, occlusion of the SMA in patients with

TWO CASES OF VESICOSIGMOIDAL FISTULA

50% CA stenosis was reported in approximately 3% of patients, similar to the patient in the current case. In an emergency repair for a ruptured abdominal aortic aneurysm or iliac artery aneurysm, preoperative CT angiography should be performed to evaluate the aortic branches, especially the IMAs, to prevent intestinal ischemia caused by EVAR.

Factors Influencing Wound Healing of Critical Ischaemic Foot after Bypass Surgery: Is the Angiosome Important in Selecting Bypass Target Artery?

症例1は78歳,女性.下腹部痛を主訴に当院内科を受診した.精査にてS状結腸憩室炎によるS状結腸膀胱瘻と診断,炎症所見の消退を待機し, S状結腸切除および膀胱部分切除を施行した.症例2は75歳,男性.急性汎発性腹膜炎による緊急手術症例.術前の尿所見で糞尿を呈し術中膀胱鏡を施行したが瘻孔部位は不明であり,また術中大腸内視鏡ではS状結腸の狭窄が高度で観察が不可能であった.術中所見でS状結腸が蜂窩織炎状に手拳大に腫大し他に大腸憩室を多数認めたことより, S状結腸憩室炎による膀胱瘻と診断,下行結腸に単孔式人工肛門および膀胱瘻を造設した.しかし術中のS状結腸粘膜生検で腺癌と診断されたため,初回手術より8日後にS状結腸切除術を施行した.膀胱瘻孔部は不明であったが,硬い索状の癒着が認められ,この部分の切除を行った.後者のごとく緊急手術症例では膀胱瘻の原因を同定することが困難で,術式決定のうえでの問題点と思われた.