Acute thrombosis of abdominal aortic aneurysms--report of two cases and review of the literature.

An acutely thrombosed abdominal aortic aneurysm (AAA) is a rare but devastating complication of aortic aneurysms. Incidence in reported series is approximately 0.7-2.8% of surgically managed AAA cases with an associated mortality rate of 50%. To date there have been only 46 cases of acutely occluded AAAs reported in the literature. We present our experience of 2 additional cases of acute AAA thrombosis and discuss the mechanism of thrombosis and management. The size of the aneurysm seems to be a better predictor of rupture than of thrombosis. Strong risk factors for thrombosis are the presence of concomitant iliac artery and cardiac disease. Although this complication is rare, its high mortality rate makes it an important disease to understand, recognize, diagnose, and treat for a successful outcome.

Bovine pericardium vs dacron for patch angioplasty after carotid endarterectomy: a prospective randomized study.

HYPOTHESIS: Bovine pericardium (BP) demonstrates improved intraoperative hemostasis and equivalent perioperative morbidity compared with Dacron when used as patch material for angioplasty following carotid endarterectomy. OBJECTIVE: To prospectively compare BP and Dacron patch angioplasty after carotid endarterectomy in a randomized fashion. METHODS: Ninety-five consecutive primary carotid endarterectomies were performed in a prospective randomized fashion in 92 patients. Fifty-one procedures were performed using BP and 44 using Dacron. Intraoperative suture line bleeding was subjectively evaluated by observing bleeding at 3 and 4 minutes following carotid cross-clamp removal and then objectively weighing the sponge used to tamponade bleeding during these time intervals. Perioperative morbidity, including cervical wound hematoma, transient ischemic attack, and stroke, and perioperative mortality were recorded. Statistical analysis was performed using paired t tests, chi(2) analysis, Fisher exact test, or multiple linear regression as appropriate. RESULTS: Suture line bleeding at 3 minutes was present in 7 (14%) of 51 patients in the BP group and 24 (55%) of 44 patients in the Dacron group (P<.001). Suture line bleeding evaluated at 4 minutes was present in 2 (4%) of 51 patients in the BP group and 13 (30%) of 44 patients in the Dacron group (P =.001). Net +/- SEM sponge weight (total intraoperative suture line bleeding) was 6.25 +/- 0.55 g in the BP group and 16.34 +/- 1.85 g in the Dacron group (P<.001). Total suture line bleeding was significantly affected by activated clotting time; however, multivariate analysis demonstrated that bleeding was significantly less with BP (P<.001) even after adjusting for differences in activated clotting time. CONCLUSIONS: Bovine pericardium demonstrated a statistically significant decrease in intraoperative suture line bleeding compared with Dacron. Handling characteristics were judged by the surgeons to be superior for BP. Therefore, we believe BP may be an alternative to Dacron when performing patch angioplasty of the carotid artery after endarterectomy.

Factors that predict site of outflow target artery anastomosis in infrainguinal revascularization.

INTRODUCTION: Lower extremity revascularization is indicated for limb salvage and incapacitating leg claudication. Many risk factors (age, hypertension, diabetes, tobacco use, dyslipidemia, etc) have been associated with atherosclerosis and the development of peripheral arterial occlusive disease. However, whether these risk factors or the surgical indication (claudication or limb salvage) influences the extent and location of infrainguinal disease and hence the target artery (distal anastomosis) is unclear. This study examines the risk factors and indication for infrainguinal revascularization with respect to the type of bypass performed. METHODS: Three hundred fifty-two infrainguinal revascularizations in 282 patients were retrospectively reviewed. Patient data, including demographics, cardiovascular risk factors, indications, types of revascularization, and perioperative complications and mortality, were collected. Data were analyzed with t test, chi(2) test, Fisher exact test, and multiple logistic regression. RESULTS: The indication for surgical revascularization was claudication in 70 patients and limb salvage in 282. The likelihood of a popliteal anastomosis (above or below knee) versus a tibial or pedal anastomosis was decreased with increasing age (P =.002) and diabetes (P =.0001), and smoking increased the likelihood (P =.056). However, popliteal bypass also was strongly associated with claudication as the surgical indication (odds ratio [OR], 8.7; P =.0001), and 90% of the claudicant group had undergone popliteal anastomosis. Claudication and popliteal anastomosis were both linked to smoking; 97% of subjects who underwent operation for claudication were smokers compared with 75% of subjects who underwent tibial or pedal anastomosis for limb salvage (P =.001). After adjustment for indication, the likelihood of popliteal anastomosis was still decreased with diabetes (OR, 0.46; P =.002), and age had a borderline significant effect (P =.077). When the analysis was stratified by indication for surgery, the likelihood of popliteal bypass among patients who underwent operation for claudication was not influenced by age, diabetes, or smoking. However, within the subset of patients who underwent operation for limb salvage, the likelihood of any popliteal anastomosis was diminished by diabetes (OR, 0.50; P =.007), age (OR, 0.968 per year; P =.01), and chronic renal insufficiency (OR, 0.476; P =.04). CONCLUSION: Infrainguinal peripheral arterial occlusive disease is not a homogenous disease entity. Claudication and limb salvage are associated with two distinct patterns of vascular disease with different risk factors. Patients who undergo operation for claudication are seen at an earlier age, have a high prevalence of smoking, and have proximal disease and a greater likelihood of a popliteal anastomosis. In contrast, patients for limb salvage are less likely to have a popliteal bypass, favoring a more distal target outflow anastomosis that is strongly influenced by advanced age, diabetes, and chronic renal insufficiency.