Glycine preserves function and decreases necrosis in skeletal muscle undergoing ischemia and reperfusion injury.

Background: Glycine (GLY) is a neutral amino acid that has been shown to be cytoprotective in the kidneys of dogs and rabbits undergoing ischemia-reperfusion injury. To investigate whether GLY exhibits a protective effect on skeletal muscle subjected to ischemia and reperfusion injury, we used a well-described gracilis muscle model in canines.

Methods: Twelve adult mongrel dogs were subjected to 6 hours of ischemia in 1 randomly selected side.

Posterior transverse plication technique for treatment of redundant internal carotid artery during endarterectomy.

Purpose: Posterior transverse plication (PTP) has gained popularity as a technique to correct redundancy of the internal carotid artery during endarterectomy. The safety of this technique in large series of patients has not been extensively studied. We investigated 876 primary carotid endarterectomies (CEAs) performed at our institution over the last six years to determine the safety of this technique.

Lessons learned from a 6-year clinical experience with superior vena cava Greenfield filters.

Purpose: Therapy to prevent pulmonary embolism (PE) resulting from upper extremity deep venous thrombosis (UEDVT) remains controversial despite an increasing incidence of DVT of upper extremity origin. The purpose of this study was to evaluate the results of 72 superior vena cava Greenfield filters (SVC-GFs) placed in patients at risk for PE arising from UEDVT.

Methods: During the past 78 months, we placed SVC-GFs in 72 patients with UEDVT in whom anticoagulation was either deemed contraindicated (n = 67) or proved ineffective in preventing recurrent PE (n = 4) or extension of the thrombus (n = 1).

Upper extremity deep venous thrombosis: an underrecognized manifestation of a hypercoagulable state.

Although lower extremity deep venous thrombosis (LEDVT) has been associated with a hypercoagulable state, there are scant data available for patients presenting with upper extremity deep venous thrombosis (UEDVT). Therefore, we conducted a prospective study to determine whether such an association exists for UEDVT. Fifty-two patients who presented with UEDVT at our institution from August 1996 to June 1997 underwent a hematological profile consisting of activated protein C (APC) resistance, antithrombin III (ATIII) level and activity, factor V mutation (arginine 506 to glycine), protein C level and activity, protein S level and activity, factors II and X activity, lupus anticoagulant, and cardiolipin antibody.

Effect of p53 gene therapy combined with CTLA4Ig selective immunosuppression on prolonged neointima formation reduction in a rat model.

In a previous study, we have demonstrated a significant reduction of neointimal formation following adenovirus-mediated gene transfer of p53 to the injured rat carotid artery. The purpose of this study was to determine if the effect of p53 gene in reducing neointimal formation would still be present up to 8 weeks after arterial injury and whether it could be enhanced by adding immunosuppression. Cytotoxic T lymphocyte-associated antigen-4 Ig (CTLA41g), a novel immunosuppressive agent, is a recombinant soluble protein that blocks T cell-dependent immune response.

Clinical experience with superior vena caval Greenfield filters.

Purpose: To evaluate the results of superior vena caval (SVC) Greenfield filters in patients at risk for pulmonary embolism (PE) secondary to upper extremity deep venous thrombosis (UEDVT).

Methods: Over a 46-month period, 26 patients (10 men, mean age 67 years, range 25 to 89) with UEDVT in whom anticoagulation was contraindicated (n = 22) or ineffective in preventing recurrent PE or extension of the thrombus (n = 4) were treated with placement of SVC Greenfield filters.

Results: One SVC filter was misplaced into the innominate vein but left in place; this vein remains patent after 2 months without evidence of filter migration.

Lower-extremity revascularisation without preoperative contrast arteriography in 185 cases: lessons learned with duplex ultrasound arterial mapping.

Purpose: we have previously reported our experience with lower-extremity duplex-ultrasound arterial mapping (DUAM) compared to contrast arteriography (CA) to predict lower-extremity bypass sites. The present study evaluates arterial revascularisation procedures for chronic limb ischaemia based on DUAM.

Materials And Methods: from January 1998 to July 1999, 195 patients (128 men, 67 women) underwent 211 lower-extremity revascularisation procedures based on DUAM.

Comparison between supra- and infrainguinal inflow sites for infrapopliteal PTFE bypasses with complementary arteriovenous fistula and vein interposition.

Purpose: the purpose of this retrospective study was to evaluate whether an inflow source proximal to the inguinal ligament had an adverse effect on infrapopliteal bypasses with complementary arteriovenous fistula/vein interposition (AVF/VI) when compared to similar bypasses originating from the common femoral artery (CFA).

Patients And Methods: over the last seven years, 112 infrapopliteal PTFE bypasses with AVF/VI were performed in 103 patients. There were 58 men and 45 women with ages ranging from 47 years to 88 years (mean 71 years).

Changes in the practice of angioaccess surgery: impact of dialysis outcome and quality initiative recommendations.

Purpose: Recommendations recently published by the National Kidney Foundation-Dialysis Outcome and Quality Initiative (DOQI) included an appeal for increased use of native arteriovenous fistulas (NAVFs) to improve overall patency and contain angioaccess costs. We evaluated the impact of the DOQI recommendations on angioaccess surgery and its outcome at our institution.

Methods: From June 1996 to April 1999, 483 angioaccess procedures were performed on 247 patients.

Programmed cell death (Apoptosis) and its role in the pathogenesis of lower extremity varicose veins.

The etiology of varicose veins remains elusive. We hypothesized that abnormal cell cycle events in the vein wall may contribute to changes in its structural integrity predisposing to varicosity development. Since cell cycle checkpoint controls are linked to the signaling and execution of apoptotic cascades, possibly apoptosis is a contributing factor in the pathophysiology of varicosities.

Ruptured versus elective abdominal aortic aneurysm repair: outcome and cost.

During a recent 30-month period, we repaired 10 ruptured abdominal aortic aneurysms (RAAA) at our institution. To evaluate the survival, postoperative morbidity, and financial impact of treating RAAA, we compared these patients with 10 randomly selected patients undergoing elective AAA (EAAA). Both groups were comparable for age, gender, and incidence of diabetes, hypertension, coronary artery disease, chronic obstructive pulmonary disease (COPD), and renal failure.

P53 gene transfer to the injured rat carotid artery promotes apoptosis.

Background: In a previous study we have demonstrated significant reduction of intimal hyperplasia after adenovirus-mediated gene transfer of p53 protein to the injured rat carotid artery. The purpose of this study was to elucidate whether apoptosis is one of the mechanisms responsible for this reduction. Apoptosis, a physiologic cell death process that stabilizes cell numbers in tissues, can be independently induced by p53.

The impact of an occluded internal carotid artery on the mortality and morbidity of patients undergoing coronary artery bypass grafting.

Purpose: To evaluate whether the presence of stenosis or an occluded internal carotid artery (ICA) influences perioperative stroke and mortality rates in patients subjected to coronary artery bypass grafting (CABG).

Material And Methods: Between January 1995 and July 1998, 3,344 patients (59% males; 41% females) had CABG performed at our institution. Preoperative carotid duplex scans performed by registered vascular technologists at an ICAVL accredited laboratory were available for review in all patients.

The use of duplex ultrasound arterial mapping as an alternative to conventional arteriography for primary and secondary infrapopliteal bypasses.

Background: For more than 1 decade, duplex ultrasonography has been investigated as a potential replacement for invasive contrast arteriography (CA) prior to lower extremity revascularization. While some authors advocate the reliability of this methodology for infrainguinal imaging, revascularizations based on duplex ultrasonography alone are seldom reported. Our initial experience with duplex ultrasound arterial mapping (DUAM) for primary and secondary infrapopliteal bypasses performed without preoperative CA is reported in this series.

The value and limitations of magnetic resonance angiography of the circle of Willis in patients undergoing carotid endarterectomy.

Magnetic resonance angiography is a useful technique to determine the patency of the circle of Willis when compared with conventional four-vessel angiography. The purpose of this study is to determine whether the integrity of the circle of Willis, assessed by magnetic resonance angiography, provides adequate collateral cerebral circulation during carotid endarterectomy and correlates with internal carotid artery back pressure. Over a recent 20-month period, 35 patients were studied preoperatively with magnetic resonance angiography of the carotid bifurcations of the circle of Willis and the vertebrobasilar system.

Carotid screening with duplex ultrasound in elderly asymptomatic patients referred to a vascular surgeon: is it worthwhile?

The purpose of this study is to prospectively determine the outcome of carotid duplex ultrasound screening in patients referred to a vascular surgeon for problems other than carotid disease. During a recent 12-month period, 307 patients age 65 years and older (mean 76 +/- 8 years) were referred to one vascular surgeon for problems other than cerebrovascular disease. Fifty-one percent of the patients were male, 49% were female, 32% were diabetic, 32% were hypertensive, 31% smoked, 20% had coronary artery disease, and 64% had peripheral arterial occlusive disease.

p53 gene transfer to the injured rat carotid artery decreases neointimal formation.

Purpose: We studied the effect of adenovirus-mediated p53 gene transfer on the injured rat carotid artery to determine its ability to decrease the formation of neointima.

Methods: In vivo gene transfer was used in isolated segments of balloon-injured rat carotid arteries. Genetically modified adenovirus containing the gene encoding for wild-type p53 (AdWTp53) was applied in three concentrations: 8 x 10(10), 1.

Values and limitations of duplex ultrasonography as the sole imaging method of preoperative evaluation for popliteal and infrapopliteal bypasses.

The purpose of this study was to evaluate whether duplex ultrasound arterial mapping (DAM) can reliably replace standard arteriography (SA) in the preoperative assessment of candidates for popliteal and infrapopliteal bypasses. This is the report of a two-phase study undertaken at our institution from July 1997 to May 1998. Carefully performed DAM averted the need for preoperative SA (51 of 58 procedures).

Hemodynamic instability following carotid endarterectomy does not affect early discharge.

Over the last few years, there has been increased emphasis on early discharge of patients following carotid endarterectomy in the United States. Recent studies have shown that short-stay hospitalization for carotid endarterectomy may be safe and cost-effective. However, this is not always possible because of reasons that are not clearly delineated.

Combined coronary artery bypass grafting and abdominal aortic aneurysm repair.

Background: We report here the results of combined coronary artery bypass grafting (CABG) and abdominal aortic aneurysm (AAA) repair and the factors associated with higher mortality following this procedure.

Methods: The authors performed a retrospective chart review of 26 patients who underwent combined CABG and AAA repair between March 1990 and October 1996.

Results: No postoperative myocardial infarction or major cardiac complications were noted.

The effect of tumor necrosis factor binding protein and interleukin-1 receptor antagonist on the development of abdominal aortic aneurysms in a rat model.

Purpose: Tumor necrosis factor (TNF), interleukin 1 (IL-1), and matrix metalloproteases have been noted to be elevated in human abdominal aortic aneurysms (AAAs) as compared with normal and occlusive aortic disease. Because TNF and IL-1 have been shown to cause release of proteases that weaken the aortic matrix, it has been suggested that these cytokines may play a central role in the aortic dilatation process. To substantiate this hypothesis, we investigated the effects of TNF and IL-1 antagonists, tumor necrosis factor binding protein (TNF-BP) and interleukin-1 receptor antagonist (IL-1RA), on the development of AAAs in a well-described rat model.

Saphenous vein thrombophlebitis (SVT): a deceptively benign disease.

Purpose: The association between deep vein thrombosis (DVT) and the hypercoagulable state is a well-established entity. However, the association between saphenous vein thrombophlebitis and coagulation abnormalities has not been investigated. Although thrombosis of varicose veins typically runs a benign course, phlebitis of the saphenous system may propagate to the deep system or saphenofemoral junction that requires more aggressive therapy.

Upper extremity deep venous thrombosis and its impact on morbidity and mortality rates in a hospital-based population.

Purpose: Although much attention has been focused on lower extremity deep venous thrombosis (LEDVT), there is a relative paucity of data regarding the impact of upper extremity deep venous thrombosis (UEDVT) on morbidity and mortality rates. To increase our knowledge with the latter disease, we have reviewed our experience at our institution with 170 patients who had brachial, axillary, and subclavian vein thromboses.

Methods: Over the past 5 years, UEDVT was diagnosed in 170 patients by duplex scanning.

Upper extremity versus lower extremity deep venous thrombosis.

Background: In contrast to lower extremity deep venous thrombosis (LEDVT), it is widely believed that upper extremity deep venous thrombosis (UEDVT) is associated with minimal morbidity or mortality.

Methods: In an attempt to compare the two disease processes with respect to pulmonary embolism and mortality, we have reviewed records and performed interviews of 430 patients with LEDVT and 52 patients with UEDVT presenting to our institution between January 1994 and June 1995.

Results: Pulmonary embolism was documented by ventilation/perfusion lung scan in 9 of 52 patients (17%) with UEDVT and 33 of 430 patients (8%) with LEDVT (P <0.