Hatsuzo Uchida

Vascular reconstruction in limb salvage operations for soft tissue tumors of the extremities

Eight patients with vascular threatening soft tissue tumors underwent wide excision of the tumors followed by vascular reconstruction. Superficial femoral vessels were resected in 6 patients and popliteal vessels in 2 patients. Arterial reconstruction was performed with a synthetic graft in 4 and a reversed saphenous vein graft in 4. Venous reconstruction was performed with a synthetic graft in 5 and a saphenous vein graft in 2. Adjuvant multimodality treatment was used in 6 patients. After an average of 30 months, the revascularized vessels were found to be patent in 5 patients with arterial reconstruction and in 1 patient with venous reconstruction. Six patients maintained functional extremities. Two other patients had to have amputations, 1 because of a deep infection that involved the grafts and the other because of an acute occlusion of the reconstructed artery. Edema of the leg, which was treated successfully with an elastic support and elevation of the leg, has been observed in all patients after operation. No local recurrence has been observed with an average followup period of 42.5 months. Pulmonary metastasis developed in 2 patients, and 1 of them underwent a pulmonary metastasectomy. Limb salvage in vascular threatening soft tissue tumors using vascular reconstruction techniques is useful and preferable in some patients.

An experimental study of a new sutureless intraluminal graft with an elastic ring that can attach itself to the vessel wall. A preliminary report.

A new sutureless intraluminal graft was developed with an elastic ring made of a flat spring. The diameter of the ring could be reversibly reduced by compression. The sutureless intraluminal graft with an elastic ring can attach itself to the vessel wall by elastic expansion of the ring. The elastic-ring graft was implanted in the descending thoracic aortas of nine dogs and was evaluated histologically and angiographically at different intervals from 18 to 150 days. No complication such as detachment of the ring, aortic rupture, stenosis, or aneurysmal dilatation was observed. With the new graft neither ligation nor posterior aortic wall dissection is necessary, and no anastomotic stenosis occurs. This graft is applicable even if the diameter of the aorta is small. Therefore the elastic-ring sutureless intraluminal graft promises theoretic advantages over sutureless methods that use tape ligation.

An experimental study on spinal cord ischemia during cross-clamping of the thoracic aorta: The monitoring of spinal cord ischemia with motor evoked potential by transcranial stimulation of the cerebral cortex in dogs

The usefulness of spinal motor evoked potential by transcranial stimulation of the motor cortex (MEPt) in detecting spinal ischemia and predicting postoperative neurological dysfunction was evaluated using a model of spinal ischemia. Group 1 was comprised of 11 dogs used for measuring the basic wave form of spinal MEPt. The normal spinal MEPt response curve consists of two major peaks: peak I and peak II. The latency of peak I and peak II at T13–L1 was 6.0±0.6 and 7.1±0.6 msec, and the amplitude, 3.3±1.6 and 6.1±2.6 μV, respectively. Group 2 was comprised of six animals subjected to spinal ischemia, in which a time-related deterioration of the MEPt as well as evoked spinal cord potential (ESP) was demonstrated. The time taken until the loss of peak I and peak II was 19.2±5.3 and 21.7±6.2 min, respectively, while the time taken until the loss of ESP was 36.7±14.0 min. In group 3, comprised of seven animals, the aorta was unclamped and the animals were allowed to recover when the spinal MEPt had disappeared. Four had paraparesis immediately after the operation, two had a normal gait, one died, and one developed spastic paraplegia after 24h. We concluded that the change in spinal MEPt during spinal ischemia occurred earlier than the change in ESP, and that the loss of MEPt suggested irreversible spinal cord damage.

Beneficial effects of prostaglandin E1 on ischemic colitis following surgery on the abdominal aorta

1 (PGE1) on the intestinal circulation, an experimental dog model of ischemic colitis following abdominal aortic reconstruction was made by ligating the inferior mesenteric artery (IMA) and the internal iliac artery, with the creation of a 50% stenosis in the superior mesenteric artery (SMA). The parameters of enteric ischemia included the blood flow of the SMA, the tissue blood flow in the small intestine and left colon, the mean stump pressure of the IMA (IMAP), and the IMAP/mean systemic blood pressure ratio. With the continuous infusion of 10 ng/kg per minute of PGE1 into the descending thoracic aorta, these values increased significantly on the seventh postoperative day compared with those on the day of operation. These results thus suggest that the continuous intraarterial infusion of PGE1 may reduce ischemic changes in the colon following abdominal aortic reconstruction.

Satigrel, a New Antiplatelet Agent, Inhibits Platelet Accumulation in Prosthetic Arterial Grafts

BACKGROUND Early and late vascular obstruction are both related to platelet adhesion and aggregation in the grafts. We assessed the effect of satigrel, a new oral antiplatelet agent, on the accumulation of indium-labeled platelets in knitted Dacron grafts inserted proximal to the femoral artery. METHODS Nine patients with arteriosclerosis obliterans receiving grafts were treated with satigrel, and 10 others were enrolled as untreated controls. Scintigraphy was performed in postoperative weeks 2 and 4, and the ratio of the scintillation count of the graft to that of the native artery was calculated to assess platelet accumulation. RESULTS In both weeks 2 and 4, the ratio was significantly smaller in the satigrel group than in the control group for the whole graft, the proximal anastomosis, and the distal anastomosis. CONCLUSIONS Satigrel significantly inhibited platelet accumulation in vascular grafts and thus may be useful for preventing postoperative graft occlusion.

Buerger's disease in a middle-aged woman with diabetes mellitus. A case report.

Buergers disease or thromboangiitis obliterans with involvement of small arteries of the upper and lower extremities usually afflicts young male smokers, but this report presents a middle-aged female nonsmoker with diabetes mellitus who satisfied clinical, angiographic, and histologic criteria for the diagnosis of Buergers disease.

Prosthetic Aneurysm in an Axillofemoral Dacron Bypass Graft

types of synthetic fibers. A number of publications have already appeared describing complications of graft dilation or rupture of prostheses secondary to yarn deterioration. 1-8 The following case report illustrates such yarn deterioration in an axillofemoral knitted Dacron graft. This case is reported to stress that patients bearing any type of vascular prosthesis should be observed throughout their lifetime for this complication.

Anastomotic rupture of aortic grafts.

Proximal suture line disruption is one of the severe complications of syn thetic vascular grafting for arteriosclerotic aortic disorders. The pathology of clinical and experimental cases revealed that a small bite of each stitch cut into the host aorta and became disrupted. Making each stitch as large as possible in the host aorta is the first procedural choice for aortic replacement surgery. Protecting the anastomotic line with a synthetic mesh cloth wrapping is prefer able.

The Influence of Residual Below-Knee Reflux and Incompetent Perforating Veins on Venous Function after Stripping Surgery

Persisting incompetent great saphenous vein (GSV) below the knee and residual incompetent perforating veins (IPV) are often found after selective stripping of GSV from the groin to upper calf. The aim of this study is to evaluate the venous function when the calf GSVs or calf perforating veins are incompetent after stripping surgery. One hundred-thirty-one limbs were treated by stripping from the groin to upper calf with stab avulsion or sclerotherapy of varices. One month and twelve months after surgery, the patients were examined clinically to establish the extent of persisting varices by duplex ultrasonography and air-plethysmography. Venous filling index (VFI) was a little higher in those who had residual calf GSV reflux 12 months later; it was also higher in the group with incompetent perforating veins than the group without. The chief complaints were found to have improved in all groups. The findings suggest that removal of the saphenous vein below the knee is not necessary, but it is important to take care of the incompetent perforating veins. (English Translation of Jpn J Phlebol 2011; 22: 239-244.).

Acute Effect of Aliskiren on Smoking-Induced Endothelial Dysfunction in Smoker

Methods: Nineteen male smokers were enrolled. After all participants smoked a cigarette, their endothelial function was assessed with brachial artery flow mediated dilation (FMD). An hour after the administration of aliskiren, they smoked again, their FMD was assessed again. A month later, all measurements were performed again without the administration of aliskiren as a control. Blood pressure, plasma renin activity, and serum interleukin-6 concentration were also examined at the same time of FMD measurement.