No abstract

We report herein the successful surgical treatment of a patient with high-output cardiac failure which developed from a high-flow hemodialysis arteriovenous fistula of the Brescia-Cimino type. Banding correction of the venous limb of the fistula with a woven Dacron prosthesis resulted in marked improvement of the cardiac failure. An ultrasonic study showed the fistula flow of 3.2 l/min to be as high as 40% of the resting cardiac output, or 8.0 l/min, before banding, while an intraoperative electromagnetic study was useful for controlling the degree of banding and showing the decrease of fistula flow from 3.7 l/min to 1.4 l/min.

A collagen-impregnated graft, called Hemashield, has been used clinically; however, some complications such as pyrexia, fluid accumulation, and unusual scar formation around the graft have been reported. To understand the cause of these problems, the graft was examined both in vivo and in vitro. Endotoxin and (1-3)beta-D-glucan were detected in the extract from Hemashield by special quantitative methods called Toxicolor and Endospecy. In an animal study, the grafts were implanted in the thoracic descending aorta of 9 dogs and were designed to explant at 2 weeks. Macroscopic evaluation of the explants showed that the graft had no infection, but fluid accumulation was found in the pleural cavity and around the graft-like seroma. Microscopical observations revealed that neither fibroblasts nor capillary blood vessels had infiltrated in the adventitial side of the graft, but numerous plasma cells, lymphocytes, and macrophages were noticed. The impregnated collagen was partially absorbed. These results indicate that the graft had some contaminants which contained a certain amount of endotoxin and (1-3)beta-D-glucan, resulting in noninfective inflammatory responses around the graft.

The graft worked perfectly as a right ventricular-pulmonary arterial valved conduit without anticoagulant therapy for a long time.

We report herein the case of a 56-year-old man found to have an isolated dissecting aneurysm of the superior mesenteric artery (SMA) after he presented with a 3-day history of postprandial epigastralgia of sudden onset. An echogram showed marked dilatation of the SMA and a high level of peripheral echoes in a linear fashion within its lumen. A thin-section contrast enhanced computed tomography revealed a thin flap, separating two distinct well-enhanced lumina. Angiography confirmed the presence of a localized dissecting aneurysm of the SMA. The patient was treated conservatively and has since been followed up as an outpatient. Following the presentation of this case, the problems regarding the diagnosis and management of this rare disease are discussed based on a review of the literature.