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.

Impaired endothelial prostacyclin production of the canine vein graft in a poor distal runoff limb

BACKGROUND

Because blood flow modulates endothelial prostacyclin production, the extent of this production in autologous vein grafts implanted in poor distal runoff limbs needed to be examined.

METHODS

Endothelial prostacyclin production in canine autologous vein grafts was measured in poor distal runoff limbs (poor runoff group) and compared with findings in normal runoff limbs (control group). Vein grafts were perfused in a closed circuit at 3 days and 1, 2, 3, and 4 weeks after implantation; after perfusion for the first 30 minutes in a steady flow (basal prostacyclin production), the grafts were exposed to arachidonic acid (stimulated prostacyclin production) for the following 30 minutes. Prostacyclin, as the metabolite 6-keto-PGF1 alpha, was radioimmunoassayed.

RESULTS

Basal and stimulated prostacyclin production increased in both groups during a period of time after implantation. At 2 weeks when endothelialization was complete, prostacyclin production in the poor runoff group was impaired, compared with the findings in the control group, and this difference increased with time. At 4 weeks the stimulated prostacyclin production was 18.91 +/- 4.03 ng/cm2 in the control group and 11.60 +/- 1.67 ng/cm2 in the poor runoff group (p < 0.05).

CONCLUSIONS

We propose that the impaired capacity of the vein graft to produce prostacyclin in a poor distal runoff may lead to loss of graft patency in reconstructed arteries.

Natural course of endothelium-dependent and -independent responses in autogenous femoral veins grafted into the arterial circulation of the dog

We examined the natural course of endothelium-dependent and -independent responses in reversed autogenous vein grafts during regeneration and tissue repair processes after vein grafting in dogs. Vein grafts implanted in the canine femoral artery were removed, cut into rings, and suspended in organ chambers for isometric tension recording at 3 days and 1, 2, 4, and 6 weeks after implantation. Endothelial cells were denuded from some rings. Control veins were taken from nonsurgically treated femoral veins. Acetylcholine caused endothelium-dependent relaxations in the control veins, whereas in the vein grafts there was no evidence of endothelium-dependent relaxations to acetylcholine 3 days after the operation. Acetylcholine caused endothelium-independent contractions throughout the study. The endothelium-dependent responses to ADP and calcium ionophore A23187 were constantly maintained. Three days after the operation, the amplitude of norepinephrine-induced contractions of the vein grafts was impaired, and at 1 week the amplitude was recovered, although it was significantly smaller than the amplitude of contractions of the control veins at any postoperative period. Endothelium-independent relaxations to sodium nitroprusside were maintained throughout the study. Thus, there was a selective loss of acetylcholine-mediated relaxation in vein grafts in the early postoperative stage, a time when the intima is not thickened. These altered responses in vein grafts in the early postoperative period may have a role in graft failure.

Laparoscopic ligation of splenic artery aneurysm

Efforts should be made to avoid splenectomy because host resistance is maintained by the spleen. We describe here a 50-year-old woman in whom laparoscopic ligation of a splenic artery aneurysm 3.0 cm in diameter was successfully performed, without major complications. Computed tomography performed 5 months later revealed no infarction in the spleen. For this patient with liver cirrhosis and cholelithiasis, laparoscopic cholecystectomy was performed at the same operation. Laparoscopic surgery is most feasible when the splenic artery is markedly tortuous and protrudes from the pancreas.

Graft replacement of pararenal inferior vena cava for leiomyosarcoma with the use of venous bypass

Total replacement of the inferior vena cava across the renal vein confluence was successfully performed under venovenous bypass in a patient with primary leiomyosarcoma of the inferior vena cava. Concomitant resection of metastases by right nephrectomy, partial hepatectomy, and cholecystectomy allowed recurrence-free survival for the past 20 months. To the best of our knowledge, this is the first report of successful replacement of the inferior vena cava for a primary tumor.

The potential risk for subclavian vein occlusion in patients on haemodialysis

Subclavian vein (SCV) stenosis or occlusion can be a late complication of temporary haemodialysis or following catheterisation for intravenous hyperalimentation. In five patients with prior catheterisation or trauma of the SCV, incapacitating oedema of the upper extremity developed only after the creation of ipsilateral arteriovenous (AV) fistulas for haemodialysis. The duration of the previous catheterisation was 2 to 4 weeks. Massive upper extremity oedema developed at 10 days to 22 months with an average of 11 months after the establishment of AV fistulas. Subclavian-axillary vein bypass using a ringed polytetrafluoroethylene graft was successful for one patient and ligation of the AV fistulae led to good results for the other three. In planning vascular access procedures in the upper extremity, venography should be mandatory to try to prevent such complications if a previous history of subclavian catheterisation exits.

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.

Possible role of cytomegalovirus in the pathogenesis of inflammatory aortic diseases: a preliminary report

To search for possible evidence of a relationship between human cytomegalovirus and aortic diseases, we examined 41 aortic lesions excised at surgery and 16 aortic tissues obtained at autopsy for the presence of cytomegalovirus DNA, by use of polymerase chain reaction. Cytomegalovirus DNA was present in seven (88%) of eight lesions of inflammatory aortic diseases with periaortic fibrosis, five of six inflammatory aneurysms, and all of two aortic occlusive lesions with inflammation. Cytomegalovirus DNA was detected in 20 (61%) of 33 atherosclerotic aneurysms, whereas it was detected in only five (31%) of 16 autopsy samples that showed neither inflammation nor atherosclerosis. Thus the possibility that cytomegalovirus may play a role in the pathogenesis of inflammatory aortic diseases warrants further attention.

High aortic occlusion associated with lupus anti-coagulant

Lupus anti-coagulant (LAC) has been recognised in association with venous and arterial thrombotic events. We retrospectively investigated the relationship between LAC and 21 patients with juxtarenal high aortic occlusion. Four of the 21 patients were LAC positive (19%), one of whom was a woman suffering from systemic lupus erythematosus (SLE). The three men had neither SLE nor any other connective tissue disease. The mean age of the four patients was 43.5 years and three of them (75%) were younger than 50 years of age. By contrast, the mean age of the 17 patients without LAC was 59.9 years and 14 of them (82.4%) were older than 50 years. The postoperative courses in all four patients with LAC undergoing arterial reconstructions were uneventful. Two patients were treated by either anti-coagulation or anti-platelet agents, postoperatively. The present paper demonstrates for the first time that, in patients with juxtarenal high aortic occlusion, the incidence of LAC positivity is higher in younger patients (below 50) than in older patients (above 50). In addition, our results show that a preoperative evaluation of the presence of LAC is required in cases with juxtarenal high aortic occlusion, particularly when the partial thromboplastin time (PTT) is prolonged and the patients are younger than 50 years old.

Rupture of embolised coeliac artery pseudoaneurysm into the stomach: is coil embolisation an effective treatment for coeliac anastomotic pseudoaneurysm?

An elderly woman with an anastomotic pseudoaneurysm of the coeliac artery, after previous treatment of a thoraco-abdominal aortic aneurysm, was treated by stainless steel coil embolisation. One year later, the embolised pseudoaneurysm ruptured into the stomach and total gastrectomy and aneurysmorraphy was necessary. She is leading a normal life 6 months later.

Hemodynamics and the development of anastomotic intimal hyperplasia of the polytetrafluoroethylene graft in dogs

To clarify whether or not changes in wall shear stress play a determinant role in the induction of anastomotic intimal hyperplasia of polytetrafluoroethylene (PTFE) grafts, two experimental models were devised. Based on our previous study (J Vasc Surg, 1985), wall shear stress was defined by variation of wall shear stress (tau-variation) in one cardiac cycle. In experiment I, PTFE grafts were implanted into dogs under conditions of 85.2 +/- 36.2 ml/min of low flow rate with 66.7 +/- 31.1 dyne/cm2 of low tau-variation. In experiment II PTFE grafts were implanted under conditions of 10.1 +/- 4.6 ml/min of low flow rate with 120.4 +/- 37.2 dyne/cm2 of moderate tau-variation. The intimal thickness of 581 +/- 127 microns at one month and 1230 +/- 260 microns at three months implantation at the distal anastomosis under an abnormal flow condition in experiment I was statistically significant compared with findings in the case of 124 +/- 36 microns at 1 month and 171 +/- 74 microns at 3 months at the proximal anastomosis under an abnormal flow condition in experiment I, and with those of 164 +/- 68 microns at 1 month and 195 +/- 57 microns at three months at the distal anastomosis in experiment II (p less than 0.01). Under a normal flow condition, there was no evident intimal hyperplasia at proximal and distal anastomotic sites in experiment I. These observations are pertinent evidence that change in wall shear stress and not the rate of blood flow is the determinant factor related to development of intimal hyperplasia of PTFE grafts at the distal anastomosis.

Intraoperative flow waveform analysis aids in preventing early graft failure following reconstruction of arteries of the legs

To enable early detection and treatment of vascular defects leading to early graft failure, intraoperative flow waveform analyses were carried out during lower extremity arterial reconstructions in 226 patients undergoing 102 aortoiliac/femoral and 124 femorodistal bypass grafts. Flow waveform types III or IV indicated early graft failure. These were noted in seven grafts (6.9%) in the aortoiliac/femoral position and in eight grafts (6.5%) in the femorodistal position. The main cause of the abnormal flow waveform pattern was misinterpretation of preoperative arteriographic findings in aortoiliac/femoral reconstructions and technical errors in anastomoses in femorodistal reconstructions. Of 15 grafts with an abnormal flow waveform pattern, 13 were effectively repaired with patch angioplasty, graft extension, or replacement with thrombectomy. In two grafts, the repair failed and amputation had to be done. Thus, intraoperative flow waveform analysis is a simple, useful, and safe method to detect vascular defects leading to early graft failure. Unless assessment of preoperative arteriographic findings in aortoiliac/femoral reconstructions are accurate and anastomotic techniques in femorodistal reconstructions are refined, early graft failure may occur.

Endothelium-derived relaxing factor and vein grafts

Platelet thrombosis, intimal hyperplasia and progression of atherosclerosis are the most important factors determining the patency of vein grafts for arterial occlusive disease. Interactions between aggregating platelets and the vessel wall play an important role in all of these processes. Recently, it has become evident that the endothelium modulates the underlying vascular smooth muscle by releasing an endothelium-derived relaxing factor, a potent vasodilator and anti-aggregating substance. Little information is available, however, on such endothelial functions of autogenous vein grafts. This review focuses on vascular modulation by endothelium-derived relaxing factor in vein grafts.

Laser thermal angioplasty for early repair of anastomotic stenosis after lower extremity arterial reconstruction: initial experience

Laser thermal angioplasty with a sapphire hot-tip Nd-YAG laser system was effectively used for five grafts with anastomotic stenotic lesions which occurred after femoro-popliteal arterial reconstructions. Stenotic lesions were detected by a combination of Doppler flow waveform analysis and ankle/brachial index measurement in 32 femoro-popliteal and five femoro-tibial arterial bypass grafts in the postoperative period. The laser probe used was 3 to 4 mm in diameter. There were no perforations of the arterial wall caused by thermal ablation, even with repeated pulses of 40 watts of laser energy for 3 s. Contact Nd-YAG laser thermal angioplasty using this rounded, 3-4 mm hot-tip facilitated effective widening of the lumen of the anastomotic stenotic lesion. All patients remain well at follow-up from 9 to 20 months after laser thermal angioplasty.

Surgical repair of primary aorto-jejunal fistula associated with non-specific inflammatory abdominal aortic aneurysm

A 28-year-old man with aorto-jejunal fistula associated with primary saccular abdominal aortic aneurysm (AAA) was effectively treated by resection and replacement with polytetraflouroethylene graft. The aetiology was suspected to be a non-specific aortitis, a rare cause of aorto-enteric fistula.

Evaluation of proposed standards for runoff in femoropopliteal arterial reconstructions: correlation between runoff score and flow waveform pattern. A preliminary report

The Ad Hoc Committee on Reporting Standards of the Society for Vascular Surgery and the International Society for Cardiovascular Surgery (SVS/ISCVS) proposed a new angiographic scoring system that grades the quality of vessels distal to the expected bypass site and calculates an overall runoff score. To assess the predictability of the bypass grafts by this runoff scoring system, we compared this runoff score with postoperative increase in the ankle/brachial index (delta ABI) and intraoperatively measured flow waveform patterns in 60 patients undergoing femoropopliteal bypass grafts. No correlation was found between delta ABI and the runoff score. Graft-patent survival time correlated with the runoff score (r = 0.44, p = 0.02). Grafts with type 0 or I flow waveform pattern with a satisfactory long-term patency had a significantly lower runoff score than grafts with type II, III or IV flow waveform pattern (p less than 0.05). When all the grafts were arbitrarily divided into two groups (grafts with a runoff score over 4.5 and those with a score of less than 4.0), a superior long-term patency was obtained in the low runoff score group with polytetrafluoroethylene (p less than 0.01) and saphenous vein grafts (p = 0.04), but not in the group with composite grafts (p = 0.25). Thus, the SVS/ISCVS runoff scoring system can be used to predict the fate of bypass grafts in femoropopliteal arterial reconstructions.

Simulated blood flow and the effects on prostacyclin production in the dog femoral artery

Effects of blood flow on the production of prostacyclin (PGI2) were examined in the canine femoral artery perfused ex vivo. Each artery was perfused in situ with medium 199, under conditions of simulated blood flow. To simulate the normal and abnormal blood flow waveforms at the same mean flow rate, we developed a flow apparatus capable of making various waveforms by changing the duration when the electromagnetic valve in the circuit was open. Group I (n = 7) was exposed to a steep acceleration waveform followed by a steep deceleration, as the normal flow waveform; group II (n = 7) was exposed to a gentle sloping waveform in the deceleration phase, as the abnormal flow waveform. PGI2 was measured as 6-ketoprostaglandin F1 alpha. PGI2 production was estimated as the cumulative production for the first 5 minutes (acute response) and as the production rate after the first 30 minutes (stable production rate). Under conditions of normal flow, the acute response was 5.87 +/- 2.16 ng/cm2/5 min, whereas under conditions of abnormal flow, the rate was 2.20 +/- 0.27 ng/cm2/5 min (p less than 0.01). Stable production rates were 82.5 and 37.5 pg/cm2/min, respectively (p less than 0.05). Both the acute response and the stable production rate of PGI2 production were greater under conditions of simulated normal flow as compared with findings in the case of an abnormal flow. Our working hypothesis is that the decreased production of PGI2, as well as a deterioration in the implanted graft, under conditions of abnormal blood flow leads to a loss of late patency of the reconstructed arteries.

Possible transmission of serum hepatitis in liver surgery with the ultrasonic dissector

When the ultrasonic dissector is used during liver surgery, the possibility exists of the transmission of virus to the attending hospital personnel because of unavoidable splashing of the irrigating solution. It becomes apparent from this study that the titer of hepatitis B surface antigen in the aspirated irrigating solution is almost the same level as that in the serum. We therefore strongly recommend that eye shields should be used in hepatic surgery when the ultrasonic dissector is in use.

Isotopic study of the effects of platelets on development of intimal thickening in autologous vein grafts in dogs

The effects of platelets on the development of intimal thickening of arterially transplanted autologous vein grafts was investigated using canine poor run-off models. A new apparatus consisting of a shielding lead block to measure in vivo platelet adherence only on the intima of the vein graft was developed. In 23 dogs, 51Cr-labelled platelets (20 microCi/kg) were injected and isotope emission over the grafts was counted. Platelet adherence was expressed as the thrombocyte accumulation index (TAI), i.e. the ratio of counts over the graft under an abnormal flow condition in the poor run-off model to those over the graft under normal flow conditions of the contralateral leg. The TAI of the total graft (TTAI) was significantly high immediately and on the first and third days after implantation. The TAIs of the proximal (PTAI) and distal (DTAI) portions of the vein graft were also high at these same times. At 7, 10, 14 and 21 days, the TAI was almost equal to 1.0, a time at which endothelial regeneration was complete as confirmed by scanning electron microscopy. Thus, the prominent intimal thickening of arterially transplanted autologous vein grafts in dogs, induced under an abnormal flow condition, correlates well with the enhanced platelet adherence on the intima of the vein grafts in an early period after implantation.

Ultrastructural evidence of the effects of shear stress variation on intimal thickening in dogs with arterially transplanted autologous vein grafts

Based on our findings that changes in wall shear stress, not the rate of blood flow, were the main hemodynamic factor related to intimal hyperplasia of autologous vein grafts, we further investigated the effect of wall shear stress variation on sequential ultrastructural changes in the intimal hyperplasia of arterially transplanted autovein grafts, using canine models. As noted, wall shear stress variation (tau-variation) could be defined by the variation in wall shear stress within a cardiac cycle, using a desktop flow waveform analyzer. In Group I, which had a high flow rate of 78.4 +/- 4.6 ml/min and low tau-variation of 36.1 +/- 2.2 dynes/cm2, intimal hyperplasia was significant. Ultrastructurally, there was a marked transformation of intimal smooth muscle cells to secretory cells 2 to 4 weeks after implantation. The surface of the intima was lined with modified smooth muscle cells at 2 weeks after implantation. In Group II, which had a low flow rate of 5.6 +/- 2.2 ml/min and normal tau-variation value (174.6 +/- 13.0 dynes/cm2), intimal hyperplasia was minimal, and there were several layers of contractile type smooth muscle cells, with characteristic myofibrillae. The surface of the intima was lined with endothelial cells at 2 weeks after implantation. These findings suggest that, in regions of low wall shear stress variation, intimal smooth muscle cells of autovein grafts may well become secretory cells, and enhanced platelet adherence could occur during early intimal repair, causing intimal hyperplasia to develop.

Computational simulation method of intraluminal velocity profile proved by laser Doppler velocimeter

Measurement of the intraluminal velocity profile within an artery may provide insight into predicting the prognosis of arterial reconstruction. To confirm the results of the computer simulation method a laser Doppler velocimeter using an optical fiber was applied to canine femoral arteries with good or poor runoff, and the intraluminal velocity profile was measured directly. Under normal flow conditions, remarkable fluctuation was obtained at the layer adjacent to the wall, whereas under poor runoff conditions, stagnation of flow was seen at the layer adjacent to the wall. These results showed that our computational simulation method which calculates the intraluminal velocity profile was a reliable, valid method of on-line analysis of the intraluminal velocity profile.

Successful simultaneous repair of coincidental bleeding malignant lymphoma of the stomach and expanding abdominal aortic aneurysm

In a 61-year-old Japanese man, a concomitant bleeding gastric malignant lymphoma and expanding abdominal aortic aneurysm was evident. Bacterial studies were done for a further 32 laparotomy cases. The patient underwent abdominal aortic aneurysmectomy and partial gastrectomy simultaneously. The postoperative course was uneventful except for temporary pneumonia. The positive rate for bacterial culture in cases of gastric or colorectal cancers was significantly high compared with that in the cases of abdominal aortic aneurysm. From the viewpoint of bacterial contamination, these two operations should be done separately. However, simultaneous operations as in the current case are feasible if great care is taken.

Flow waveform analysis and long-term results of autogenous saphenous vein and polytetrafluoroethylene grafts in 140 arterial reconstructions of the lower limbs

In previous work we have found that the outcome of grafts in the lower limbs correlated with the flow waveform pattern of the artery. We have retrospectively reviewed 140 femoro-popliteal bypass operations involving the use of 75 saphenous vein grafts and 65 polytetrafluoroethylene (PTFE) grafts. For grafts with type 0 or I flow waveform pattern the patency at 4 years (56%) was superior to grafts with the type II, III or IV flow waveform (35%) patterns (P less than 0.05). For saphenous vein grafts with type 0 or I flow, the patency rate was 78% at 3 years and 69% at 5 and 8 years. In contrast with type II, III or IV flow the patency rate was 52% at 3 years, 48% at 5 years and 34% at 8 years, with a statistical significance at 4 years (P less than 0.05). PTFE grafts with type 0 or I flow showed a tendency toward an increased patency which was not significant in comparison with the grafts with type II, III or IV flow (P = 0.12). Saphenous vein grafts with type II flow patterns had an increased occlusive rate in the first year whereas PTFE grafts had the same tendency within 2 years. In both types of graft, early occlusions within a month of operation were encountered in grafts with a type III or IV flow waveform pattern. These results indicate that the fate of the reconstructed arteries of the lower limb could be predicted by flow waveform analysis, and a careful and serial postoperative evaluation of the graft should be made, particularly those with type II, III or IV flow waveform patterns.

Recurrent multiple aneurysms in an axillofemoral graft with coagulopathy

An 84-year-old man presented with multiple non-anastomotic aneurysms in a Dacron axillary femoral graft and coagulopathy. Histological examination and the clinical course suggested that a graft versus host reaction might be the main cause of the aneurysms.