Failure of knitted dacron as an arterial prosthesis.

The incidence of failure of knitted Dacron arterial prostheses is thought to be significantly greater than that reported in the literature. Five cases of immediate and late defects in grafts of various manufacture are reported and a sixth case is discussed. The development of increased porosity to achieve more complete graft healing is thought to play a role in both early and late graft failure. Although the precise etiologic mechanisms are yet to be determined, the Dacron fibers were noted to become separated with subsequent widening of the graft interstices with resulting hemorrhage through the "intact" prosthetic material. Related theories of explanation are reviewed, and guidelines for study of these defective prostheses are suggested. It is essential that this complication of arterial grafting be recognized and that pertinent clinical experiences be documented in the surgical literature.

Perigraft seromas complicating arterial grafts.

A collection of clear, sterile fluid, confined within a nonsecretory fibrous pseudomembrane surrounding a vascular graft, is a specific clinicopathologic entity termed perigraft seroma. Our experience with four such cases prompted a clinical study of our own material and that of others. A comprehensive survey, including the entire North American Chapter of the International Society for Cardiovascular Surgery membership, provided 279 cases for detailed analysis. Material most commonly involved were knitted Dacron (54%) and polytetrafluorethylene (34%), with knitted Dacron in the axillofemoral position accounting for 31% of the cases. The fluid was documented as serum by biochemical and electrophoretic analysis. Histopathologically, the grafts were noted to be poorly incorporated into the surrounding tissues, and the graft lining was covered by a flimsy, fibrous layer with a degenerated fibrin-protein matrix noted in the interstices of the graft. These findings pertained to both polytetrafluoroethylene and Dacron; neither acute nor chronic inflammatory changes were noted. The cyst membrane was comprised of nonsecretory cells, primarily fibroblasts. Treatment was highly variable. Graft replacement provided a 92% cure rate, and the authors advocate removal of the original graft and cyst membrane with placement of a new graft of material other than the original along a different anatomic route. However, in elderly, poor-risk patients, resolution may occasionally be achieved by "watchful waiting" with or without multiple aspirations.

The posterior stocking seam approach to radical subfascial clipping of perforating veins.

The posterior stocking seam approach to radical subfascial ligation of perforating veins has been advocated for the patient with postphlebitic syndrome presenting with severe stasis dermatitis, leg edema, and recurrent ulceration. Our indications for this procedure have been extended to include signs and symptoms of advanced venous insufficiency which persist after multiple operative procedures for recurrent varicose veins in the absence of deep venous thrombosis. In this series of twenty-five operations there was one instance of recurrent stasis ulceration after the procedure, and reversal of the pigmentation of stasis dermatitis was dramatic in the majority of cases. All limbs have completely healed, and there has been no significant swelling. The long-term results of this surgical procedure have been excellent, and short-term complications have been minimal.

Long-term follow-up of vena caval clips and umbrellas.

Fifty-one consecutive cases of inferior vena caval interruption for documented pulmonary embolism are reported. Forty-four patients underwent transabdominal vena caval clipping using the multichannel Adams-DeWeese clip, and seven critically ill patients were treated with vena caval umbrella. Operative mortality was 4 per cent. Only one patient developed edema attributable to clipping whereas postinterruption stasis sequelae were common after umbrella insertion. Vena cavography at six months and eight years demonstrated 85 per cent patency in the clip group and 16 per cent in the umbrella group.

Application of intestinal staplers to aortoiliac surgery.

Although intestinal stapling devices have become an accepted part of the contemporary gastrointestinal surgeon's armamentarium, little attention has been given to their application to vascular surgical operative techniques. We have found the TA stapler helpful in surgery of the abdominal aorta, the iliac arteries, and their branches. It is most applicable to aortic bypass surgery for both atherosclerotic occlusive and aneurysmal disease. The TA 30, 50, and 90 devices designed to introduce a double row of overlapping staples effect a secure, hemostatic, and watertight bowel closure. These staples can likewise achieve a secure, bloodtight closure when used appropriately in aortic surgery. In aortofemoral bypass grafting performed with a proximal end-to-end anastomosis, the TA 30 or 55 is ideal for expeditious closure of the transected, distal aortic stump. The stapling technique also greatly simplifies obliteration of common, external, and internal iliac aneurysms to prevent back-bleeding when these aneurysms are excluded from the main reconstructed arterial stream. In the resection of abdominal aortic aneurysms associated with multiple iliac branch aneurysms, the technique eliminates the necessity of placing sutures in deep, inaccessible areas. Tangential staple occlusion of common iliac aneurysms, allowing retrograde flow from the distal femoral anastomosis into the internal iliac artery, preserves pelvic visceral perfusion. Our experience in approximately 50 cases, employing the TA stapling device in a variety of aortoiliac artery operative situations, is outlined.

Preliminary experience with a large scale vascular registry.

The preliminary study carried out on a voluntary basis, has illustrated the feasibility of a large scale vascular registry serving as a benchmark against which a standard of practice of vascular surgery can be assessed. An initial experience with 165 surgeons active in the clinical practice of surgery (contributing 8,800 major vascular reconstructive cases in a 9 month period) suggests access to an enormous data base of vascular surgery practice against which community standards may be measured.

Occult deep venous thrombosis complicating superficial thrombophlebitis.

PURPOSE: To determine whether superficial thrombophlebitis (STP) can extend into the deep venous system (DVS) and whether this may result in pulmonary embolization. METHODS: All venous duplex ultrasound examinations performed in our vascular laboratory to rule out deep venous thrombosis from June 1, 1994, to June 24, 1996, were reviewed. RESULTS: Of 8313 limbs studied by duplex scanning in 6148 patients, 1756 limbs (21.1%) had a positive result for deep venous thrombosis. STP was demonstrated in 232 limbs (213 patients), of which 20 (8.6%) extended into the DVS. Fourteen (70%) were noted on the initial scan, and six (30%) were detected on serial follow-up scans. Eighteen (90%) originated in the proximal greater saphenous vein and extended across the saphenofemoral junction into the common femoral vein. Nine demonstrated "free-floating" thrombus with a "tongue" extending into the common femoral vein while still attached proximally to the greater saphenous vein. Extension of thrombus from the lesser saphenous vein into the popliteal vein was noted in two cases (10%). One pulmonary embolization was directly observed to occur in real time during scanning. No pulmonary embolization was seen when STP did not involve the DVS. CONCLUSIONS: STP can extend into the DVS. In this series STP of the proximal greater saphenous vein extended into the common femoral vein in 8.6% of the cases, of which 10% embolized to the lungs. When the DVS is involved, standard deep venous thrombosis treatment (heparin, warfarin, bed rest) should be instituted. We recommend duplex imaging for STP involving the greater saphenous vein in the thigh to rule out occult deep venous thrombosis. STP is not always benign and self-limiting as previously described.

Tibial artery false aneurysm: uncommon result of blunt injury occurring during athletics.

Two young men presented with symptoms following lower extremity injuries sustained in the normal course of participation in sports. One played baseball while the other competed in Tae Kwon Do. One case presented with digital ischemia, the other developed a pulsating hematoma. Each came to angiography, and each proved to have a false aneurysm of a tibial artery. The tibial artery was ligated in each case, without further complications. The patient with digital ischemia was thought to have sustained microemboli, and also underwent lumbar sympathectomy.

Clinical significance of aortic graft dilation.

To determine if there is a relationship between aortic graft dilation and graft complications, 443 serial ultrasound studies performed on 106 patients were analyzed. Of 443 studies, 243 were done retrospectively on 59 patients from 3 to 144 months (mean, 38 months) after graft implantation. Forty-seven additional patients were studied prospectively, with direct measurement of external graft diameter after aortic clamp release. Subsequent ultrasound examinations at 3, 6, 9, and 12 months and then annually (n = 200) were routinely performed. Mean follow-up was 12 months (range, 3 to 48). Knitted double velour Dacron prostheses were used in all cases reported in this study. This cohort was culled from our ongoing graft surveillance program, which includes grafts of other materials and manufacturers. Comparison of the manufacturer's recorded box size with follow-up ultrasound measurements in all cases demonstrated a mean increase in graft diameter of 3.7 mm (23%). Little dilation occurred after 1 year. In 47 patients with direct graft diameter measurements taken after declamping, an immediate mean increase of 1.7 mm (11%) was noted. Dilation was not related to surgical indication (aneurysm vs occlusive disease) or hypertension. Analysis of the 10% segment of the series with the greatest dilation (mean, 39%) did not demonstrate a predilection for graft complications. No significant dilation was noted in the single cases encountered of femoral and iliac anastomotic aneurysms and perigraft seroma. Although dilation of knitted Dacron grafts is to be anticipated, no association between graft dilation and graft complications was found in this series.

Retroperitoneal nonresective staple exclusion of abdominal aortic aneurysms: clinical outcome and fate of the excluded abdominal aortic aneurysms.

PURPOSE: The purpose of this article was to prospectively study analyses outcome after staple exclusion of abdominal aneurysms with specific follow-up of the excluded aneurysm. Whether these data may predict behavior of aneurysms excluded from the circulation by transluminal grafting procedures is also addressed. METHODS: Staple exclusion of abdominal aneurysms with bypass via retroperitoneal incisions was performed in 100 consecutive patients undergoing elective procedures. Risk factors, clamp time, operative time, transfusions, length of stay, complications, platelets, fibrinogen, and fibrin split products were documented. Duplex imaging was performed quarterly for 1 year after exclusion and at least annually thereafter. Serial measurements of aneurysm size and evaluation for thrombosis was obtained. RESULTS: Aneurysm size averaged 5.5 cm. Risk factors included history of smoking (54%), history of heart disease (51%), hypertension (41%), hyperlipidemia (34%), and chronic obstructive pulmonary disease (25%). Clamp time averaged 51 minutes. Forty-eight required no intraoperative transfusion, and 19 needed only autologous blood; the average 24-hour transfusion was 313 cc. Length of stay averaged 11 days, with a median of 8 days, and correlated with age, aneurysm size, and risk factors. The 30-day mortality rate was 4%. Death was associated with longer operative and anesthesia times and with age and risk factors. As calculated by life-table analysis to 5 years, 96.8% of aneurysms thrombosed. No aneurysm expanded, became symptomatic, nor ruptured. Perioperative platelet, fibrinogen, and fibrin split product assays show no evidence of disseminated intravascular coagulation or consumptive coagulopathy. CONCLUSIONS: Staple exclusion and bypass of abdominal aneurysms as described in this study is safe and effective. There has been neither aneurysm expansion nor rupture, and the technique reliably leads to thrombosis of aneurysms without coagulopathy.