1: J Vasc Surg. 2003 May;37(5):1032-5.
Improved patency of prosthetic arteriovenous grafts with an acute anastomotic angle and flow diffuser.
Hakaim AG, Nalbandian MN, Heller JK, Chowla AC, Oldenburg WA.
Section of Vascular Surgery, Mayo Clinic, Jacksonville, FL 32244, USA. [email protected]
OBJECTIVE: Conventional end-to-side anastomosis to establish venous outflow for prosthetic arteriovenous grafts often requires operative patch angioplasty within 1 year because of venous stenosis. Rather than conventional venous anastomosis, a modified end-to-side anastomosis at a 15-degree angle with a flow diffuser was constructed. Such diffusers allow decreased flow velocity and increased pressure, inhibiting boundary layer separation. METHODS: Ten brachial artery to axillary vein 6 mm straight se-polytetrafluoroethylene prosthetic arteriovenous grafts were created with this technique. Patients included 6 men and 4 women (mean age, 66.4 years; range, 54-80 years), all with renal failure and a history of diabetes. The degree of stenosis at the venous anastomosis was determined with duplex scanning at intervals of 6 months. Analysis of survival and cumulative primary patency estimates were determined with the Kaplan-Meier method. RESULTS: Primary cumulative patency estimate of 100% for the modified group at 18 and 24 months was significantly greater than that for age-matched historic control fistulas with the conventional end-to-side anastomosis (n = 20): 18 months, 32%; 24 months, 32% (P <.05). Although venous stenosis could not be quantitated for thrombosed conventional fistulas, modified anastomoses had minimal stenosis at 24 months: mean area reduction, 30% (range, 20%-45%). CONCLUSION: Incorporation of a flow diffuser and a 15-degree anastomotic angle significantly increases patency of prosthetic brachial artery to axillary vein grafts.
Publication Types:
PMID: 12756350 [PubMed - indexed for MEDLINE]
Improved patency of prosthetic arteriovenous grafts with an acute anastomotic angle and flow diffuser.
Hakaim AG, Nalbandian MN, Heller JK, Chowla AC, Oldenburg WA.
Section of Vascular Surgery, Mayo Clinic, Jacksonville, FL 32244, USA. [email protected]
OBJECTIVE: Conventional end-to-side anastomosis to establish venous outflow for prosthetic arteriovenous grafts often requires operative patch angioplasty within 1 year because of venous stenosis. Rather than conventional venous anastomosis, a modified end-to-side anastomosis at a 15-degree angle with a flow diffuser was constructed. Such diffusers allow decreased flow velocity and increased pressure, inhibiting boundary layer separation. METHODS: Ten brachial artery to axillary vein 6 mm straight se-polytetrafluoroethylene prosthetic arteriovenous grafts were created with this technique. Patients included 6 men and 4 women (mean age, 66.4 years; range, 54-80 years), all with renal failure and a history of diabetes. The degree of stenosis at the venous anastomosis was determined with duplex scanning at intervals of 6 months. Analysis of survival and cumulative primary patency estimates were determined with the Kaplan-Meier method. RESULTS: Primary cumulative patency estimate of 100% for the modified group at 18 and 24 months was significantly greater than that for age-matched historic control fistulas with the conventional end-to-side anastomosis (n = 20): 18 months, 32%; 24 months, 32% (P <.05). Although venous stenosis could not be quantitated for thrombosed conventional fistulas, modified anastomoses had minimal stenosis at 24 months: mean area reduction, 30% (range, 20%-45%). CONCLUSION: Incorporation of a flow diffuser and a 15-degree anastomotic angle significantly increases patency of prosthetic brachial artery to axillary vein grafts.
Publication Types:
PMID: 12756350 [PubMed - indexed for MEDLINE]
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2: Mayo Clin Proc. 1999 Oct;74(10):999-1010.Related Articles, Links
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Endovascular repair of abdominal aortic aneurysms: where do we stand?
Seelig MH, Oldenburg WA, Hakaim AG, Hallett JW, Chowla A, Andrews JC, Cherry KJ.
Department of Surgery, Mayo Clinic Jacksonville, FL 32224, USA.
Endovascular repair of abdominal aortic aneurysms has evolved dramatically within the past few years. In light of the potential to reduce morbidity and mortality associated with open surgical repair, endoluminal grafting offers therapeutic options to patients who are not surgical candidates because of comorbidities. With the development of bifurcated devices, more complex aneurysms may be treated by endovascular grafting. Although successful placement of endovascular grafts requires a pronounced learning curve, including appropriate patient selection, midterm results seem consistent with those of traditional open repair of aneurysms. This review describes the current indications, minimal requirements, different devices and associated techniques, and potential complications of endoluminal repair of abdominal aortic aneurysms. Future aspects of endoluminal grafting are also discussed.
Publication Types:
PMID: 10918865 [PubMed - indexed for MEDLINE]
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3: Am Surg. 1999 Sep;65(9):881-3.Related Articles, Links
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Primary hepatic lymphoma in hepatitis C: case report and review of the literature.
Chowla A, Malhi-Chowla N, Chidambaram A, Surick B.
Division of Surgery, Mayo Clinic Jacksonville, Florida 32224, USA.
Primary B-cell lymphoma of the liver is an extremely rare tumor. The higher incidence of hepatocellular carcinoma in hepatitis C is well known, but the relationship with lymphoma is unclear. An increased incidence has been reported in patients with chronic hepatitis C. Hepatitis C virus is known to be a lymphotropic virus. Mixed cryoglobulinemia, which is a benign lymphoproliferative disorder, has a definite association with hepatitis C. It is postulated that the virus may also induce a malignant transformation. We describe an unusual presentation of a case of asymptomatic left hepatic mass in a patient with hepatitis C with a preoperative diagnosis of hepatocellular carcinoma. He underwent a left lateral segmentectomy, and the pathologic examination revealed non-Hodgkin's lymphoma. The clinical features, radiologic investigations, and pathologic findings are presented. A review of the literature discussing clinical features, postulated pathogenetic mechanisms, and management options is also presented.
Publication Types:
PMID: 10484095 [PubMed - indexed for MEDLINE]
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4: Mayo Clin Proc. 1999 Sep;74(9):870-6.Related Articles, Links
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Erratum in:- Mayo Clin Proc 1999 Oct;74(10):1056.
Use of intraoperative duplex ultrasonography and routine patch angioplasty in patients undergoing carotid endarterectomy.
Seelig MH, Oldenburg WA, Chowla A, Atkinson EJ.
Department of Surgery, Mayo Clinic Jacksonville, Fla 32224, USA.
OBJECTIVE: To determine the value of routine patch angioplasty and intraoperative duplex ultrasonography (US) during carotid endarterectomy (CEA) for high-grade internal carotid artery stenosis. PATIENTS AND METHODS: The charts of 102 consecutive patients who underwent CEA with routine patching and intraoperative duplex US for treatment of high-grade carotid stenosis between June 1991 and January 1997 were reviewed retrospectively. Recurrent stenosis was defined as a narrowing in the common or internal carotid artery of more than 40%. RESULTS: Of 102 patients, 65 (63.7%) were men, and 37 (36.3%) were women (mean age, 72.4 years). Thirteen patients (12.7%) had bilateral CEAs. Intraoperative duplex US revealed abnormalities during 29 (25.2%) of 115 CEAs; 14 abnormalities (12.2%) were major and underwent immediate revision. No perioperative neurologic events or deaths occurred. Mean length of follow-up was 21.3 months (range, 1.3-72.6 months). Late neurologic events occurred in 2 patients, and 5 patients died during follow-up. All neurologic events and deaths were unrelated to the patients' carotid surgery. Twelve patients (11.8%) developed moderate restenosis (40%-69%). In 4 of these patients restenosis resolved during further follow-up. No patient developed severe recurrent carotid stenosis. CONCLUSION: Morbidity and mortality following CEA with routine patch angioplasty and intraoperative duplex US appear to be low. Routine intraoperative duplex US detects correctable technical problems that subsequently lead to a low incidence of symptomatic stenosis. The low incidence of recurrent stenosis suggests that routine postoperative follow-up may not be necessary or cost-effective unless the patient has symptoms or a contralateral stenosis.
PMID: 10488787 [PubMed - indexed for MEDLINE]