Satoru Funahashi

Intimal hyperplasia of experimental autologous vein graft in hyperlipidemic rabbits with poor distal runoff.

Poor distal runoff and hyperlipidemia are factors affecting the fate of an implanted graft. In the present study, combined effects of poor distal runoff and hyperlipidemia on intimal hyperplasia (IH) of the vein graft were examined in a newly developed poor distal runoff model in rabbits. A poor distal runoff model was prepared in the right hindlimb of 30 rabbits. These animals were divided into two groups, depending on the diet provided; normolipidemic diet group (Group NL, n = 14) and hyperlipidemic 1% cholesterol diet group (Group HL, n = 16). Four weeks after preparing the poor runoff model, the femoral vein was implanted into the ipsilateral femoral artery. At 2, 4 and 6 weeks, the grafts were harvested. IH of the graft was measured and macrophages in the IH were examined immunohistochemically. Intimal cell proliferation was also determined by bromodeoxyuridine (BrdU) incorporation. IH of the vein graft was significantly accelerated in cases of poor distal runoff and hyperlipidemia. There were no macrophages in the IH in the NL group. In the HL group, macrophages infiltrated the outer layer of IH, sometimes just above the internal elastic lamina, and increased with time. In the poor distal runoff limbs at 6 weeks, macrophages also appeared in the subendothelial layer but were absent in that layer in the controls. Intimal cell proliferation expressed as the BrdU labeling index (LI) was maximum at 2 weeks. In the HL group, BrdU LI of IH in the poor distal runoff limb was higher than in the control at 2 and 4 weeks. Throughout the experiments, BrdU LIs in the HL group were significantly higher than in the NL. Hyperlipidemia accelerates intimal cell proliferation to a greater extent, then does IH. In cases of a poor distal runoff, the enhancement of cell proliferation by hyperlipidemia is augmented. These responses, in the presence of a hyperlipidemia, may be closely related to the migration of macrophages.

Management of concomitant abdominal aortic aneurysm and gastrointestinal malignancy

Selecting the most appropriate surgical approach for patients with abdominal aortic aneurysm (AAA) and gastrointestinal malignancy remains controversial. In an attempt to develop guidelines for the management of patients with these two simultaneous lesions, a retrospective review of patients who had concomitant AAA and gastrointestinal malignancy was undertaken. During the period from January 1985 to February 1993, 229 patients with AAA were admitted to our hospital. Among these, 19 patients (8%) had a gastrointestinal malignancy together with AAA and were divided into 2 groups. Group I was composed of 11 patients who underwent either a 1- or a 2-stage operation for both lesions. Group II was composed of eight patients who either underwent an operation for one lesion (six patients) or did not have any operation (two patients). Among group I, six patients underwent the two-stage operation. In four of the six patients, the malignancy was resected first. In the remaining two patients, the aneurysmectomy was performed first, because, in one patient, the aneurysm was more than 6 cm in diameter, and, in the other patient, the aneurysm was a saccular type. Among group I, five patients (two patients with gastric cancer, and one patient each with esophageal cancer, rectal cancer, and malignant lymphoma of the stomach) underwent a one-stage operation. In three of the five patients (two patients with gastric cancer and one patient with esophageal cancer), simultaneous resection was carried out by using segregated approaches, namely, the retroperitoneal approach for AAA and the transperitoneal approach for malignancy. Although the clinical characteristics of the patients were different, 8 of the 11 patients (73%) in group I are still alive, whereas only 1 of the 8 patients (13%) in group II is still alive. The principles of our surgical approaches for concomitant AAA and gastrointestinal malignancy are as follows: (1) The lesion that absolutely indicated urgent surgery was resected first. (2) If both lesions were asymptomatic, the malignancy was resected first. (3) Simultaneous resection using different approaches was useful in some patients with concomitant upper early gastrointestinal malignancy. (4) Both lesions need to be resected eventually for better long-term survival.

Surgical strategy of concomitant abdominal aortic aneurysm and gastric cancer

PURPOSE Selecting the most appropriate surgical approach for patients with abdominal aortic aneurysm (AAA) and concurrent gastric cancer remains controversial. In an attempt to develop guidelines for the management of two concurrent lesions, a retrospective review of patients with concomitant AAA and gastric cancer was undertaken. METHODS During the period from January 1985 to December 1992, a total of 222 patients with AAA were admitted to our hospital. Among these, seven patients (3.2%) had gastric cancer and concurrent AAA. Six of the seven patients were treated surgically for both lesions with either a one- or two-stage operation. One patient underwent only an exploratory laparotomy because of the peritoneal dissemination of the gastric cancer. Four of the six patients underwent a two-stage operation. In three cases, the resection of the malignancy was performed first because the gastric cancer was diagnosed as advanced before operation. In one case, the aneurysmectomy was performed first because the aneurysm was more than 6 cm in diameter and the gastric cancer was in an early stage of development. Two of the six patients underwent a one-stage operation and a simultaneous resection was carried out by way of segregated approaches, such as the retroperitoneal approach for AAA and the transperitoneal approach for the malignant lesion. RESULTS Five of the seven patients (71.4%) are still alive. The length of follow-up for these patients ranged from 4 months to 4 years. CONCLUSIONS The principles of our surgical approaches for concomitant AAA and gastric cancer are as follows. (1) The lesion that absolutely indicates urgent operation should be operated on first. (2) If the malignant lesion is advanced, it is resected first. (3) If the malignancy is not advanced, the AAA should be resected first by the retroperitoneal approach. (4) Simultaneous resection by way of segregated approaches is useful in some patients with early gastric cancer. (5) Both lesions must be resected eventually for improvement of the long-term survival chances.

Simultaneous Resection of Abdominal Aortic Aneurysms and Early Gastric Cancer by Retroperitoneal and Transperitoneal Approach

The surgical approach to patients with abdominal aortic aneurysm and gastrointestinal malignancy remains controversial. We experienced two cases with abdominal aortic aneurysm and gastric cancer, which were treated by a one-stage operation using a different approach. At first, the operation for the aneurysm was done through a retroperitoneal approach and then, a partial gastrectomy for gastric cancer was done through a transperitoneal approach. The postoperative course of both cases was uneventful. The patients were discharge on the 19th and 21st postoperative days, respectively. This one-stage operation using different isolated approaches, such as the retroperitoneal approach for abdominal aortic aneurysm and transperitoneal approach for gastric cancer, was useful for the patients with abdominal aortic aneurysm and particularly early gastric cancer in terms of preventing an infection of the prosthetic graft.

Late graft failure of autologous vein grafts for arterial occlusive disease: Clinical and experimental studies

Late graft failure following arterial reconstructive surgery, especially after infrainguinal reconstruction, remains a major concern for vascular surgeons. To more effectively predict the outcome of reconstructed arteries, we herein propose an intraoperative flow waveform analysis which correlates well with the long-term patency rate of grafts. According to this flow waveform analysis, late graft failure was occasionally seen in grafts with type II waveforms when poor distal runoff vessels had been shown by the preoperative arteriogram. Next, to investigate which events occurring in autologous vein grafts under abnormal hemodynamics may contribute to late graft failure, a distal poor-runoff model was made in the canine femoral artery. In this review, we present the results of our investigation on autologous vein grafts using this poor-runoff model. We also relate our recent findings on the function of regenerated endothelium in autologous vein grafts.

Correlation of long-term results of extra-anatomic bypass and flow waveform analysis

To investigate the correlation between the long-term results of an extra-anatomic bypass and operative flow waveform analysis, we retrospectively reviewed 32 axillofemoral and 21 femorofemoral bypasses for between 1 and 5 years after surgical repair. For the grafts with a type O or I flow waveform pattern, the patency at 3 years (83%) and at 5 years (83%) was superior to grafts with a type II flow waveform (69 and 60%). For the axillofemoral bypass grafts with a type O or I waveform, the patency rate was 92% at 5 years. In contrast with the type II flow, the patency rate was 70% at 5 years. For the femorofemoral bypass with a type O or I and a II flow waveform, the patency at 4 years was 67 and 46%, respectively. In cases with concomitant superficial femoral artery occlusion, the flow waveform was type O or I in 23% and type II in 77%. The patency rate at 5 years was 85% for cases with a patent superficial femoral artery, and 51% for an occluded superficial femoral artery (p < 0.05). These results suggest that the long-term outcome of extra-anatomic bypass correlates with the operative flow wave analysis. In addition, good long-term results and an accurate flow wave pattern depend on the distal run-off, particularly the presence of a patent superficial femoral artery.

Hypereosinophilic Syndrome Accompanying Gangrene of the Toes with Peripheral Arterial Occlusion A Case Report

The authors herein report the case of a teenage boy who presented with peripheral arterial occlusion of both upper and lower extremities associated with hypereosinophilia. During a 10-year follow-up, corticosteroid therapy was continued for the treatment of hypereosinophilia. The patient underwent bilateral lumbar sympathectomies because of severe ischemia of the bilateral lower extremities with gangrene of the toes. Based on the progress of his disease over the past 10 years, he was suspected to have idiopathic hypereosinophilic syndrome (HES) accompanied by peripheral arterial obstruction. Idiopathic HES is a disease characterized by unexpected hypereosinophilia, which may lead to organ damage. This is a very rare case of peripheral arterial occlusion associated with idiopathic HIS.

Properties of endothelium and smooth muscle cells in canine femoral arteries after lumbar sympathectomy

OBJECTIVE To find out whether the lumbar sympathectomy modulated the endothelial function (as measured by nitric oxide (NO) and prostacyclin (PGI2), and blood flow in the canine femoral artery. DESIGN Laboratory experiments. SETTING Teaching hospital, Japan. ANIMALS 16 mongrel dogs. INTERVENTION Unilateral sympathectomy from L3 to L6. MAIN OUTCOME MEASURES Five weeks later, the changes in blood flow, the endothelium-dependent responses and the PGI2 production in the canine femoral arteries were measured. RESULTS The median (range) blood flow of left (denervated) and right (innervated) femoral arteries was 162 ml/min (122-330) and 65 ml/min (40-92), respectively. There was a significant difference between the two groups (p < 0.01). The endothelium-dependent relaxations to acetylcholine, adenosine diphosphate (ADP) and A23187 were comparable. The amounts of PGI2 produced in the two groups were similar. Direct relaxation in response to sodium nitroprusside was also similar in the two groups. CONCLUSIONS Lumbar sympathectomy did not alter the endothelial function, although the median blood flow in the denervated femoral arteries was significantly higher than in the innervated ones. The continuous vasodilatation after sympathectomy may be a more potent factor in the regulation of vascular tonus than the physiological regulation of NO and PGI2.

Successful Simultaneous Resection of Abdominal Aortic Aneurysm and Rectal Cancer A Case Report

The surgical approach to patients with an abdominal aortic aneurysm (AAA) and gastrointestinal malignancy remains controversial. The Authors experienced a case with AAA and rectal cancer, which was treated by a successful one-stage operation. At first, the operation for the aneurysm was done through a transperitoneal approach, and then, an abdominoperineal resection for rectal cancer was simultaneously done with a closed-bowel resection by the stapling technique. The postoperative course was uneventful. The patient was discharged on the thirty-second postoperative day. From the standpoint of bacterial contamination, these two operations should be done separately; however, simultaneous operations such as the one described herein are possible if great care is taken.

Operative Transluminal Laser Angioplasty as the Sole Treatment for Late Stenoses of Femorodistal Artery Bypass Graft: Experimental and Clinical Studies

To determine the role of Nd:YAG laser thermal angioplasty as the sole treatment for late stenoses of femorodistal artery bypass graft, the lasing effect of a larger size of hot-tip probe (3, 4, and 5 mm) was experimentally studied in vitro. For an adequate lasing effect, 30 watts of laser power output for 3 seconds was needed for the 3 mm probe, 40 watts for the 4 mm probe, and 50 watts for the 5 mm probe, respectively. Based on these results, we used Nd:YAG laser thermal angioplasty alone for 25 grafts, including 16 polytetrafluoroethylene (PTFE) grafts, eight saphenous vein grafts, and one externally supported (EXS) Dacron graft in which the stenotic lesions were detected by deterioration of the Doppler flow waveform pattern or a significant fall in the ankle/brachial pressure index (ABPI). Follow-up was from 3 to 24 months (average of 9 months) for PTFE grafts, from 5 to 21 months (average of 11 months) for saphenous vein grafts, and 13 months for the EXS Dacron graft following femorodistal artery reconstructions. Stenotic lesions were most common in the distal anastomotic sites: 11 PTFE grafts, three saphenous vein grafts, and one EXS Dacron graft. Among these, 13 grafts showed a type II flow waveform pattern at the time of surgery. Clinical success was achieved in 12 of the PTFE grafts (75%), in five of the vein grafts (62.5%), and in the single EXS Dacron graft. Four PTFE and three saphenous vein grafts failed subsequent to repeat intraoperative balloon angioplasty in three and graft extension in three and one graft interposition. Perforation occurred in only one vein graft. Continuing patency has now been maintained for up to 25 months after lasing. Nd:YAG laser thermal angioplasty using a 3 to 5 mm hot-tip probe is effective as the sole procedure for widening a stenotic lesion and improving patency after femorodistal artery reconstruction.