Robert Courbier

Suggested standards for reports dealing with cerebrovascular disease

The evaluation of clinical reports on vascular disease is often made difficult by variations in descriptive terms, clinical classification, and outcome criteria. In 1983 the Joint Council of the Society for Vascular Surgery and the North American Chapter of the International Society for Cardiovascular Surgery created the Ad Hoc Committee on Reporting Standards to address these problems and recommend solutions. Some general problems were addressed in the initial report dealing with lower extremity ischemia. This article concerns clinical standards for reports dealing with cerebrovascular disease, suggests a scheme for clinical classification, and recommends standardized reporting practices for grading risk factors, angiographic and other diagnostic findings, and the results and complications of therapeutic intervention.

Expanded PTFE Prostheses as Arterial Substitutes in Humans: Late Pathological Findings in 73 Excised Grafts

Through collaboration of surgeons, pathologists and bioengineers at five centers in Canada and France, this study analyzed the late pathology and structural changes in 73 expanded PTFE arterial prostheses harvested from patients at autopsies and reoperations. The degree of tissue encapsulation increased with the duration of implantation but was reduced by the presence of infection. In several cases, the fibrous tissue penetrated the wall of the prosthesis and partitioned off the thin outer layer, thus disrupting the delicate microporous structure of the wall. The presence of aneurysms was observed in models that had no external reinforcing layer and among grafts that apparently suffered from surgical trauma. Wrinkling of grafts was noted at areas of flexion and was often associated with thickening of the external capsule and reduced luminal diameters. Endothelialization was found within only a few millimeters of the anastomoses. The luminal surfaces were generally not well healed. The PTFE structure was usually readily visible under a thin covering of loosely adhering thrombotic deposits. Bacteria were observed in 46% of the cases, even though only 29% were considered clinically infected. The incidence of lipid or cholesterol deposits was high. Avoiding iatrogenic trauma to the external wall of the prosthesis during implantation is important. Those features where design improvements are required to provide longer term structural integrity and dimensional stability in future models of expanded PTFE prostheses should be identified.

Secondary Aortoduodenal Fistulas: Value of Initial Axillofemoral Bypass

Between January 1970 and April 1989, 20 patients underwent operation for secondary aortoduodenal fistulas. When the preoperative diagnosis was certain and emergency control of bleeding not required, initial axillofemoral bypass was performed before ablation of the infected aortic prosthetic graft during the same operation. When diagnosis was uncertain or severity of bleeding required emergency laparotomy, the therapeutic plan varied over time. Until 1980, we performed either a direct repair (three cases) or the ablation of the aortic graft followed by secondary axillofemoral bypass (four cases). After 1980, the order of procedures was 1) control of bleeding whenever necessary, 2) axillofemoral bypass, and 3) ablation of the aortic graft. Postoperative mortality was two of 13 in patients undergoing initial axillofemoral bypass, compared with six of seven patients undergoing direct surgery or initial ablation of the aortic graft. Of the 12 patients surviving the postoperative period, three died of aortic stump hemorrhage, four, 12, and 14 months after operation. Two patients had a new aortic graft inserted. Repeat replacement of the abdominal aorta graft was performed in one case and ascending thoracic aortobifemoral bypass in the other because of secondary thrombosis of the axillofemoral bypass. We conclude that initial axillofemoral bypass before dealing with the aortic graft improves the immediate prognosis in operations for secondary aortoduodenal fistulas. This procedure does not, however, preclude the possibility of aortic stump infection which can lead to recurrent aortoduodenal fistula. The risk of infection or secondary occlusion of axillofemoral bypass is minimal. Secondary prosthetic replacement is not systematically necessary.

Pre- and Intraoperative Transcranial Doppler: Prediction and Surveillance of Tolerance to Carotid Clamping

We report 91 patients (mean age 70 years) operated upon, prospectively for a total of 100 carotid revascularizations (nine bilateral). Eighty-five of these patients had pre-, intra-, and postoperative transcranial Doppler investigations. Preoperatively, these 85 patients (92 procedures) were classified into two groups based on the results of their Doppler examinations: Group A (65 patients, 72 procedures), those who did not require an intraoperative indwelling shunt and Group B (20 patients, 20 procedures), those who did. The shunt was inserted only when the mean stump (back) pressure was less than 50 mmHg after cross-clamping. Group A all had satisfactory collaterality with a functional anterior and one or two posterior communicating arteries. Group B had no communicating arteries (anterior or posterior) identified by transcranial Doppler. In 17 of 20 patients in this group, the stump pressure was less than 50 mmHg and a shunt was placed. The overall prediction based on Doppler examination of whether or not patients would need a shunt during operation for the two groups A and B (i.e., 92 procedures) was correct in 95.6% (88/92) of cases. Moreover, six hemodynamically significant stenoses (four in the cavernous portion, two in the middle cerebral artery) were disclosed. Sensitivity and specificity of transcranial Doppler as correlated with arteriographic findings were 70 and 90%. Preoperative transcranial Doppler can measure the velocities of the principal cerebral arteries and the collateral capacity of the circle of Willis, and can forecast tolerance to carotid cross-clamping. Intraoperatively, the velocity of flow in the middle carotid artery was correlated with stump pressure, which allowed for surveillance of the shunt.

False Aneurysm of the Abdominal Aorta Due to Brucella Suis

A 48-year-old man presented with a fissured false aneurysm of the abdominal aorta due toBrucella suis. Clinical findings were lumbosciatic pain, fever, and sudation. Diagnosis was reached through abdominal computed tomographic (CT) scan and arteriograms. An extremely large false aneurysm, thrombosed and perforated posteriorly, was found in the infrarenal aorta. Semiurgent therapy consisted of resection of the aneurysm and prosthetic Dacron graft replacement associated with a transposed omental wrap. Antibiotic therapy was administered for three months. Although bacteriologic specimens were negative, brucellosis was diagnosed because of a positive Wright test and high Brucella antibodies in this patient originating from an endemic area. Six months after surgery he is apparently in good health.

Unfastening of an Adams-de Weese clip: An uncommon cause of recurrent pulmonary embolism after interruption of the inferior vena cava

Recurrent pulmonary embolism after placement of a caval clip is uncommon. We report the case of a patient admitted for recurrent venous thrombosis of the lower limbs, 11 years after placement of an Adams-de Weese clip. Severe pulmonary embolism occurred in spite of anticoagulant treatment. After an unsuccessful attempt to insert a Greenfield filter, surgery was performed. The clip was found to have come unfastened; simple repeat closure was performed. We were unable to find any similar reports in the literature. In spite of its rarity, this cause should be considered when faced with recurrent pulmonary embolism in patients having undergone inferior vena caval clipping.