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The clinical presentation of patients with acute lower-limb ischemia and primary aortic thrombus prompted this review. Following recognition of the first case in early 1994, relevant patients (n = 6) were kept in a database and were reviewed for presentation, treatment, and follow-up. The median age was 41 and five patients were male. Angiography, computed tomography, and/or magnetic resonance angiography demonstrated one or more aortic sessile or pedunculated thrombus(i) without associated atherosclerotic disease. In two cases, a retropancreatic intraaortic mural thrombus was associated with severe pancreatitis. All other cases presented with acute lower-limb emboli requiring limb salvage embolectomy. Because of significant patient illness, systemic anticoagulation was chosen acutely to prevent recurrent emboli. Interestingly, serial studies demonstrated aortic thrombus resolution. Failure to continue warfarin therapy resulted in recurrent problems (n = 1) unless the instigating event had resolved (n = 3). There were no deaths or amputations. We concluded that surgical embolectomy, when required, with subsequent anticoagulation, results in limb salvage and allows for eventual resolution of the primary aortic thrombus. Long-term anticoagulation is required unless the etiologic process resolves. The literature describes patients with atherosclerosis and overlying thrombus but fails to describe the approach to patients with primary thrombus formation.

We report a patient who presented with acute lower extremity ischemia 13 days following removal of an intraaortic balloon pump. Dissection of the infrarenal aorta, extending into the left iliac artery, was found at operation. The patient's recent myocardial infarction, prolonged ischemia with compartment syndrome, otherwise normal aortoiliac and infrainguinal arteries and the necessity for suprarenal aortic clamping for surgical repair, were all factors in the decision for endovascular repair of the dissection. Infrarenal aortic and left iliac Wallstents, placed intraoperatively, successfully occluded the false lumen of the dissection. The patient was discharged after an uncomplicated recovery and is asymptomatic with palpable pedal pulses and triphasic pedal Doppler waveforms 1 year following the procedure.

Renal and visceral artery images obtained concurrently with spiral CT and conventional arteriography were compared for 32 patients. Indications for imaging were occlusive disease (n = 12), aneurysmal disease (n = 9), and renal or visceral artery disease (n = 11). Conventional arteriography enabled visualization of 64 renal arteries and 15 accessory renal arteries. Lateral aortograms obtained in 15 patients enabled visualization of 14 superior mesenteric (SMA) and 14 celiac arteries. Spiral CT enabled visualization of 60 renal arteries, 12 accessory renal arteries, 27 SMAs, and 22 celiac arteries. Calcification or a disparity in timing of contrast material injection and scanning prevented visualization of the celiac artery in 10 patients and the SMA in four patients. With conventional arteriography as the standard for comparison, spiral CT had a sensitivity of 67% and a specificity of 95% for depiction of at least 75% stenosis in the main renal artery. By means of the Pearson correlation coefficient, significant correlation (p < 0.001) was confirmed between spiral CT and arteriography for evaluation of stenosis of the main renal artery, SMA, and celiac artery. This early experience suggests that spiral CT may be useful in evaluation of renal and visceral arteries and their relationship to aortic disease.

Thirty-three in situ saphenous vein bypass grafts were performed using a conventional open technique (CI) while 31 in situ bypass grafts were performed using endovascular occlusion of side branches (EAI). Bypass grafts were performed from the femoral to the popliteal (n = 37) or a trifurcation (n = 27) artery for claudication (n = 7), rest pain (n = 14), or tissue loss (n = 43). Wound complications developed in 11 Cl and four EAI limbs. Postoperative hospitalization in CI and EAI patients was, respectively, 8.4 +/- 2.0 days and 4 +/- 1.6 days. Missed arteriovenous fistulas were noted in one CI and 17 EAI limbs postoperatively. At follow-up four (12%) CI and six (19%) EAI grafts were occluded or had undergone revision surgery. Based on life-table analysis CI and EAI cumulative patency rates at 18 months were 79% and 83%, respectively. Although this new technique (EAI bypass grafting) did not reduce operative time, it did decrease the length of surgical incisions and the duration of postoperative hospitalization (p < 0.001, Student's t test). Wound complications occurred less frequently in EAI limbs but the incidence of missed arteriovenous fistulas was significantly higher. These data suggest that EAI and CI patency is comparable. Ultimately long-term patency will be the crucial test for determining the utility of this new technique.

This report describes a case of direct ureteral injury sustained during retroperitoneal vascular surgery. The diagnosis was delayed and treatment was complicated by infection. To address the patient's problem initially and then to consolidate our impressions, a literature review was undertaken. The conclusions from this review suggest that direct ureteral injury during vascular surgery is rare but most common during redo surgery, is just as likely to be missed as discovered during surgery, and when missed may be so for months. The diagnostic delay is caused by a varied and often misleading presentation, and a ureteral contrast study is the ultimate diagnostic tool. In these delayed cases the typical ureteral treatment is a stented ureteroureterostomy or nephrectomy. In the present case the patient was otherwise healthy; therefore an aggressive attitude to renal salvage was taken. This is a unique case of ileal conduit replacement of the damaged ureter for this specific situation. Five years after repair, renal function is stable without infectious complications. The current literature would suggest that the vascular graft may be left undisturbed if the urine is sterile. If infection is present, graft removal appears the standard of care and was successful in the present case.

Since 1987, we have used the Palmaz expandable intraluminal stent in 22 selected cases of iliac artery stenosis in 14 men and six women with a mean age of 63 years for claudication (9), graft salvage (5), rest pain (4), and tissue loss (2). Morphologic criteria included severe percutaneous balloon angioplasty-induced dissection (6), long or multiple stenoses or occlusions (5), post-percutaneous balloon angioplasty elastic recoil (4), location of stenosis (4), and restenosis following percutaneous balloon angioplasty (3). Twenty-two limbs were treated with 61 stents. The mean pressure gradient across the lesion fell from 31 +/- 15 to 1.1 +/- 2.4 mmHg after stenting. The mean ankle/brachial systolic pressure index improved from 0.59 +/- 0.31 to 0.83 +/- 0.25 after stenting. The mean follow-up is 11.4 months, with a mean ankle/brachial index at their most recent follow-up of 0.88 +/- 0.19. Symptomatically, 11 extremities are normal and five limbs are improved. Three patients have died and two have required bypass grafts for iliac occlusive disease. In this early experience, the Palmaz intraluminal stent appears to be valuable for the management of post-percutaneous balloon angioplasty restenosis, elastic recoil, and percutaneous balloon angioplasty-induced dissection, although it is not without complications.

Numerous variables are involved in the attachment of endothelial cells to a substrate. Quantifying these factors both on native vessels and on synthetic substrates is important in determining the success of endothelial cell attachment, retention, and growth on these substrates. Fibronectin is an important cell attachment molecule and is likely to be key to the successful attachment of endothelial cells to any substrate. For this reason we have developed an enzyme-linked immunosorbent assay for interrogation of the luminal surface of native and synthetic vessels for the presence of fibronectin. A plexiglass chamber was designed with two blocks, an upper block with wells and a lower supporting block. The chamber was then assembled with a vessel between the two blocks, forming the bottom of the well. This luminal surface was then interrogated by conventional enzyme-linked immunosorbent assay. Native vessels, collagenase-digested vessels, acellular matrices and PTFE preclotted with whole blood were assayed to determine the quantity of fibronectin present. These results were correlated with a bioassay developed to determine the quantity of fibronectin necessary for cell attachment. It was concluded that all of the samples assayed had ample fibronectin for cell attachment and that other factors must be responsible for successful maintenance of a cell monolayer.

A preliminary assessment was made of the acellular vascular matrix graft as a substrate for endothelial cell seeding, with respect to surface pretreatment (none versus fibronectin and/or serum) and presence of exogenous growth factor. Arteries were harvested from greyhounds and exposed to a sequential detergent extraction process to produce the acellular vascular matrix. Human umbilical vein endothelial cells were grown in tissue culture, harvested in first passage, then seeded at 10(5) cells/cm2 on sections of acellular vascular matrix and on gel-coated polystyrene positive controls. After 18 hour incubation, endothelial cell-seeded acellular matrices were fixed and processed for histologic and planimetric analysis; control wells were fixed and endothelial cells were counted by planimetry. Pretreatment of the acellular vascular matrix was found to have no effect on the percentage of endothelial cell coverage of the matrix. There was significantly better endothelial cell coverage of the acellular matrix than on matched gel-treated polystyrene control wells. Withdrawal of growth factor resulted in a significant reduction in endothelial cell coverage for all acellular vascular matrix groups. Growth factor withdrawal also significantly reduced attachment of endothelial cells on gel-treated polystyrene. Cell surface area was significantly smaller when growth factor was withdrawn from all groups except from the acellular vascular matrix without pretreatment. We conclude that: (1) the acellular vascular matrix is conductive to endothelial cell adherence and spreading even without pretreatment; and (2) sudden withdrawal of exogenous growth factor may impair early coverage of substrates by endothelial cells due to an effect on their adherence or spreading.

This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost.