bluuebunny/crossref_metadata_2025 huggingface dataset:
Carotid Endarterectomy in Patients with Renal Insufficiency: Should Selection Criteria be Different in Patients with Renal Insufficiency?
Authors: Ayerdi Juan , Sampson Lawrence N. , Deshmukh Narayan , Farid Asim , Gupta Sushil K.
Published: June 2007

The objective of this study was to elucidate the relationship between outcomes from carotid endarterectomy (CEA) in patients with and without renal insufficiency.

Carotid endarterectomy is one of the most commonly performed vascular procedures. The role of cardiac comorbidity in carotid endarterectomy has been extensively studied. The relationship between renal failure and surgical outcomes has also been studied for both coronary artery bypass grafting and lower extremity occlusive disease. However, the role of renal insufficiency in relationship to decision making regarding surgical intervention for carotid stenosis is not well defined. The authors hypothesized that the outcomes from CEA were negatively influenced by renal dysfunction. A retrospective review was made of consecutive CEAs performed at their institution from 1990 to 1995. Patients were grouped into 2 categories according to their renal function. Group A, 448 patients (90%) with creatinine level 1.8 mg/dL or less, and group B, 49 patients (10%) with creatinine levels more than 1.8 mg/dL. Data from patients on dialysis are presented but were excluded for the purpose of analysis.

Included in the study were 497 patients with a mean age of 70 +8.9 and 74 +8.9 for groups A and B, respectively. Preoperative creatinine was 1.1 (±0.25) mg/dL for group A and 2.5 (+0.81) mg/dL for group B. Outcomes were as follows: perioperative cardiac events 5.4% vs 28.6%, stroke rates 2.7% vs 2.0%, and mortality rates 0.9% vs 8.2%, for groups A and B, respectively. At 60-month follow-up the stroke rates were 7.6% vs 6.1%, and the mortality rates 22.8% vs 59.2%, for groups A and B, respectively.

While patients with chronic renal insufficiency have no increased risk of perioperative or long-term neurologic events, perioperative and long-term mortality rates are significantly increased. This significant reduction in survival should prompt a more cautious application of CEA in patients with increased creatinine.
Diameter Comparison of Saphenous Vein Bypasses for Popliteal Aneurysm Versus Peripheral Arterial Occlusive Disease in Matched Subjects
Authors: Moore Jason , Salles-Cunha Sergio , Scissons Robert , Beebe Hugh G.
Published: June 2007

Previous research has suggested that arterial aneurysm might result from a systemic tendency to dilatation. This systemic effect would involve both arterial and venous dilatation. The authors investigated whether venous grafts implanted to bypass popliteal artery aneurysms (PAA) had larger diameters than those implanted to treat peripheral arterial occlusive disease (PAOD). They compared representative diameters of 20 vein grafts implanted for PAA with matched bypass grafts implanted for PAOD. Graft diameters were obtained by means of CVI-Q M-mode ultrasound imaging. Each PAA patient/graft was matched to an equivalent PAOD patient/graft based on the patient's gender and age and the vein graft type and distal anastomosis. Secondarily, graft proximal anastomosis was matched in 60% (12/20) of the cases. Age was matched if the difference was <4 years. Average age at the time of surgery was 68 ±12 years for PAA and 68 ±13 for PAOD groups. There were 11 reversed greater saphenous vein (GSV), 2 nonreversed GSV, and 7 in situ GSV in each group. Distal anastomoses were at the popliteal (15), peroneal (3), posterior (1), and anterior tibial (1) arteries in each group. Matching was not possible for lesser saphenous and cephalic vein grafts or bypasses to the tibial-peroneal trunk. Graft diameters were significantly larger for the PAA group, 6.24 ± 0.66 mm (standard deviation), than for the PAOD group, 5.73 ± 0.69 mm (p < 0.02, Mann-Whitney U test). Of 10 bypasses with diameter > 6.5 mm, 8 were implanted for PAA. If these 10 largest bypasses were eliminated from the calculations, the mean graft diameters were 5.82 ± 0.51 mm and 5.57 ± 0.52 mm for the PAA and PAOD groups, respectively (p = 0.28). Bypass grafts implanted in PAA patients had significantly greater diameters than grafts implanted in PAOD patients. This finding, however, was due to a subgroup of grafts with diameters >6.5 mm. Perhaps systemic abnormalities associated with PAA should be first studied in patients with large vein grafts or large original veins.
Isolated Popliteal Vein Entrapment by a Fibrous Band
Authors: Nottingham James M. , Haynes James L.
Published: June 2007

Popliteal vein entrapment is commonly associated with popliteal artery entrapment, whereas isolated popliteal vein entrapment is a less common entity. The authors present a case of isolated popliteal vein entrapment caused by a fibrous band.
Effect of Cilostazol in Patients with Intermittent Claudication: A Randomized, Double-Blind, Placebo-Controlled Study
Authors: Strandness D. Eugene , Dalman Ronald L. , Panian Steve , Rendell Marc S. , Comp Philip C. , Zhang Peter , Forbes William P.
Published: June 2007

A multicenter, double-blind, randomized, placebo-controlled, parallel study was conducted to compare the efficacy and safety of cilostazol 100 mg and 50 mg, both administered twice daily, with that of placebo in patients with moderately severe intermittent claudication (IC) secondary to peripheral arterial disease. A total of 394 subjects 40 years of age or older with chronic, stable, symptomatic IC received cilostazol 100 mg twice daily, 50 mg twice daily, or placebo for 24 weeks. Subjects receiving cilostazol 100 mg twice daily experienced a 21% net improvement in maximal walking distance (MWD) compared with placebo subjects (p = 0.0003) and a 22% net improvement in distance walked to the onset of symptoms (PFWD) (p = 0.0015). Subjects who received cilostazol 50 mg twice daily also benefited from therapy, but not to a statistically significant degree (7% and 11% improvement in MWD and PFWD, respectively). Quality-of-life and functional status assessments corroborated these objective results. Cilostazol, in particular 100 mg twice daily, significantly improves symptoms in patients with IC.
Endoluminal Graft Repair of Abdominal Aortic Aneurysms by Vascular Surgeons at a Nonclinical Trial Center
Authors: Marek J. , Langsfeld M. , Dickinson R. B. , Tullis M. J. , Kasirajan K.
Published: June 2007

The purpose of this study was to compare the early results and complication rates of commercially available endoluminal grafts (ELG) for abdominal aortic aneurysm (AAA) by a team of vascular surgeons at a nontrial center with those of published results from trial centers. A retrospective chart review of all patients undergoing endoluminal graft repair of AAA was made at the medical center. From October 1, 1999, to December 31, 2000, a team of vascular surgeons electively repaired AAAs in 100 patients at a regional referral center. Of these patients, 49 underwent repair with a commercially available ELG (35 AneuRx, 14 Ancure) whereas the remaining were repaired with an open operation. In the ELG group, the primary technical success rate was 100% with a 30-day mortality rate of 2.0%. The average hospital length of stay was 3.28 days with ICU stay of 1.20 days. The average operative estimated blood loss was 501 mL (100-2,500) with average transfusions of 0.49 unit packed red blood cells (prbc) (0-6). Eighty-eight percent of ELG patients left the hospital without complication.Seven patients (14%) required 1 1 follow-up procedures for complications including endoleak, limb or graft thrombosis, graft stenosis, distal embolization, or wound complications. Three of 26 patients (1 1%) with 6-month computed tomography follow-up had evidence of endoleak (2 have subsequently undergone lumbar embolization). Only 1 6-month follow-up patient had shown increased aneurysm size before endoleak treatment. A team of board-certified vascular surgeons at a nonclinical trial center can safely perform ELG for AAA with results similar to those of published series from trial centers.
Angioplasty with Stenting Is Effective in Treating Blue Toe Syndrome
Authors: Renshaw A. , McCowen T. , Waltke E. A. , Wattenhofer S. P. , Tahara R. W. , Baxter B. T.
Published: June 2007

Blue to syndrome is a manifestation of distal embolization associated with significant pain and risk of tissue loss. The recommended treatment options for this problem include endarterectomy or bypass with exclusion of the source of emboli. Although focal arterial stenosis can be effectively treated with angioplasty, it is unclear whether performing angioplasty in a lesion suspected of causing distal embolization might actually worsen the condition or what long-term effects this would have in preventing future embolization. The purpose of this study was to evaluate the treatment and outcome of a series of patients with unilateral blue toe syndrome treated with percutaneous angioplasty and stenting. During a 5-year period, a total of 8 patients were identified with unilateral blue toe syndrome. Ankle/brachial indices (ABls) were obtained, followed by arteriography. The study group included 4 men and 4 women with an age range of 35 to 83 years. Their atherosclerotic risk factors included smoking (8), hypertension (5), diabetes mellitus (3), and hypercholesterolemia (1). One patient had a history of illicit drug use. The patients were followed up by repeat clinical examinations and vascular laboratory studies. Arteriography typically demonstrated a focal preocclusive lesion with thrombus at the distal end of the lesion. Angioplasty and stent placement was technically successful in all cases. The ABIs increased following angioplasty (before 0.81 ±0.05; after 1.02 ±.05). The symptoms resolved in all 8 patients over the ensuing month, and there were no recurrences with a mean follow-up of 18.5 months (range 4 to 36 months). There was 1 death at 4 months associated with preexisting colon carcinoma. Unilateral arterial to arterial emboli were found in association with focal preocclusive lesions. Despite the presence of thrombus in some of the lesions, these patients were not acutely worse following angioplasty. There was good initial angiographic success in all cases. There was also hemodynamic improvement as shown by the increased ankle/brachial indices. Although long-term follow-up is not available, these intermediate results suggest that angioplasty and stenting should be considered a reasonable alternative to standard operative approaches for patients with blue to syndrome associated with embolization from a focal stenosis.
A Comparison of Patch Angioplasty and Stenting for Axillary Venous Stenoses of Thrombosed Hemodialysis Grafts
Authors: Lombardi Joseph V. , Dougherty Matthew J. , Veitia Nestor , Somal Jack , Calligaro Keith D.
Published: June 2007

The efficacy of balloon angioplasty with stent placement is compared to surgical patch angioplasty for thrombosed upper arm hemodialysis grafts with stenotic lesions at the venous anastomosis. Patients with thrombosed hemodialysis grafts terminating at the axillary vein were reviewed. Thirty-eight stents were placed after thrombectomy and venous balloon angioplasty in 26 patients. Fifteen case-matched controls underwent 23 polytetrafluoroethylene patch angioplasties for similar lesions. Kaplan-Meier survival analysis was used for statistical comparison. Primary patency for stent placement compared with patch angioplasty was not statistically different at any time through 1-year follow-up (37% vs 55% at 3 months, 25% vs 45% at 6 months, and 25% vs 15% at 12 months, respectively; p = 0.37). Secondary patency rates were slightly better for patch angioplasty compared with stent placement (78% vs 59% at 3 months, 78% vs 48% at 6 months, and 54% vs 32% at 12 months, respectively) however these differences were not statistically significant (p = 0.13). There was no difference in complication rates between groups. Sustained patency is poor for both angioplasty with stent placement and surgical patch angioplasty when revising thrombosed dialysis grafts with anastomotic axillary vein stenosis. These data suggest slightly better patency for the routine use of patch angioplasty for these lesions. However, the endovascular approach appears to be a reasonable alternative when surgical exposure is difficult.
Celiac Artery Compression Syndrome: Successful Laparoscopic Treatment
Authors: Dordoni L. , Tshomba Y. , Giacomelli M. , Jannello A. M. , Chiesa R.
Published: June 2007

Several authors believe the crus of the diaphragm or the arcuate ligament is largely implicated in the etiology of the celiac artery compression syndrome (CACS). An unusual case of CACS successfully treated with laparoscopic decompression is reported. While under general anesthesia, the patient underwent laparoscopic division of the hypertrophic median arcuate ligament and dissection free of the celiac trunk. Postoperative angiography demonstrated improved flow in the celiac artery. The patient was discharged on the second postoperative day. At 6 months, Doppler ultrasound scanning and magnetic resonance angiography revealed good patency of the celiac trunk. The patient reported complete resolution of symptoms and increased weight. A laparoscopic approach allows the surgeon to sufficiently dissect the celiac axis. An excellent clinical result at short-term follow-up was attained. This is the second reported experience with this new procedure and the first successfully performed with only four port sites.
Endovascular Intervention for Stenosis Following Carotid Stent-Supported Angioplasty
Authors: Bates Mark C. , Aburahma Ali F.
Published: June 2007

This report is on a patient with symptomatic late restenosis after carotid stent-supported angioplasty (CSSA). Initially, the patient underwent carotid endarterectomy (CEA) with primary closure in response to an index transient ischemic attack 13 months before CSSA. He returned with angiographic evidence of recurrent carotid artery stenosis. A balloon-expandable stent was deployed with technical success. Follow-up angiography 1 year later showed an asymptomatic, noncritical in-stent restenosis (50%). Three years after the initial stent placement, the patient presented with ischemic symptoms and a carotid duplex confirming critical restenosis. The patient was successfully treated by deployment of a stent within a stent and showed significant hemodynamic improvement. This is a case report of late progressive restenosis, which raises concerns about long-term patency of CSSA in patients with aggressive postendarterectomy recurrence.
Pseudoaneurysm of the Subclavian-Vertebral Artery Junction
Authors: Bernik Thomas R. , Friedman Steven G. , Scher Larry A. , Safa Toufic
Published: June 2007

Pseudoaneurysm of the subclavian-vertebral artery junction (SVJ) is a rare complication of internal jugular vein catheter placement. Because of its retroclavicular location, arterial injury at the SVJ poses a significant therapeutic challenge. A case report and review of the literature are presented.
Review of Standards for Competence in Catheter-Based Endovascular Procedures: A Resource and Strategy for the Interventional Vascular Surgeon
Authors: Woratyla Steven P. , Rasmussen Todd E. , O'Donnell Sean D. , Parker Mary V. , Goff James M. , Gillespie David L. , Rich Norman M.
Published: June 2007

The field of peripheral vascular disease management is evolving. As such, vascular surgeons can no longer be complacent and expect to be included in the rapidly expanding practice of endovascular intervention. If not engaged, vascular surgeons risk losing not only the patients who have largely driven this evolution but also their role as leaders in the management of vascular disease. Therefore vascular surgeons and vascular surgical training programs find themselves in an awkward and sometimes confrontational circumstance attempting to gain experience and training in catheter-based procedures. Individual societies, both surgical and nonsurgical, have put forth competence standards for catheter-based procedures. However these standards are not always consistent and the definition of competence is often a heated debate. In addition, combining the acquisition of endovascular skills with the multitude of available endovascular training experiences, didactic and “hands-on,” is not well coordinated. The objectives of this review are to summarize the literature as it relates to catheter-based endovascular competence, including publications from nonsurgical catheter-based specialties, and to place the acquisition of basic endovascular skills in context with the available endovascular courses in a stepwise strategy. A final objective is to provide a literature-based resource that outlines specific phases in the development of interventional vascular surgeons and training programs as they advance into the arena of catheter-based endovascular therapies.
Arterial Wall Shear Stress: Observations from the Bench to the Bedside
Authors: Paszkowiak Jacek J. , Dardik Alan
Published: June 2007

Shear stress is the tangential force of the flowing blood on the endothelial surface of the blood vessel. Shear is described mathematically for ideal fluids, and in vitro models have enabled researchers to describe the effects of shear on endothelial cells. High shear stress, as found in laminar flow, promotes endothelial cell survival and quiescence, alignment in the direction of flow, and secretion of substances that promote vasodilation and anticoagulation. Low shear stress, or changing shear stress direction as found in turbulent flow, promotes endothelial proliferation and apoptosis, shape change, and secretion of substances that promote vasoconstriction, coagulation, and platelet aggregation. The precise pathways by which endothelial cells sense shear stress to promote their quiescent or activated pathways are currently unknown. Clinical applications include increasing shear stress via creation of an arteriovenous fistula or vein cuff to promote bypass graft flow and patency. Since an abnormal level of shear stress is implicated in the pathogenesis of atherosclerosis, neointimal hyperplasia, and aneurysmal disease, additional research to understand the effects of shear stress on the blood vessel may provide insight to prevent vascular disease.
Diagnosis and Management of Aneurysms Involving the Superior Mesenteric Artery and Its Branches
Authors: Lorelli David R. , Cambria Robert A. , Seabrook Gary R. , Towne Jonathan B.
Published: June 2007

Aneurysms of the superior mesenteric artery (SMA) are an uncommon but lethal entity, which must be treated expeditiously to avoid mortality and high incidence of ischemic small bowel complications. In the past 7 years the authors have treated 4 patients with a variety of types of aneurysms involving the SMA and its branches at a university-based teaching hospital. The first was a mycotic SMA aneurysm as a result of septic mitral valve, the second a jejunal aneurysm in a patient with pancreatitis, the third a spontaneous dissection distal to a small SMA aneurysm with thrombus partially occluding the distal vessel, and the fourth an SMA aneurysm associated with the diagnosis of mesenteric insufficiency. All patients presented with abdominal pain. The diagnosis was made initially in 1 patient on plain abdominal films with a calcified aneurysm, on duplex scan in the second, and on computed tomography (CT) scans in the remaining 2. Treatment consisted of bowel resection and ligation of mycotic aneurysm in the first patient, of catheter embolization of jejunal aneurysm in the patient with pancreatitis, and of vein graft bypass in the patient with a large SMA aneurysm. The patient with SMA aneurysm and distal dissection with partially occluding thrombus received anticoagulation and is being followed up with serial CT scans. There were no deaths. One patient required bowel resection, which did not result in short gut syndrome. Improved abdominal duplex scanning and CT technology facilitates the diagnosis of mesenteric aneurysm. The broad spectrum of etiologies mandates that treatment be tailored to the individual patient, and it varies from endovascular techniques to traditional bypass surgery. Prompt diagnosis and treatment results in the lowest mortality rate and minimizes the prevalence of intestinal infarction.
Controversies in Carotid Stenting
Authors: Taylor Steve , Alcocer Francisco , Jordan William D.
Published: June 2007

Endovascular therapies are now commonly used in many vascular sites. However, the role for carotid angioplasty and stenting (CAS) remains an unproven therapy with some potential benefits. Initial results of CAS were worse than the surgical standard of carotid endarterectomy (CEA) and did not meet American Heart Association guidelines. However, recent improvements have resulted in improved stroke morbidity rate that may approach that of CEA. Specifically, the embolic problem associated with CAS has been reduced with embolic protection devices, but the ultimate effect of these protection devices remains uncertain. Initial comparison studies of CAS to CEA showed an unacceptably high stroke morbidity rate in the CAS group. As a result, multiple randomized clinical trials have been initiated to compare the results of CAS with embolic protection to that of CEA. While these studies are underway, the authors advocate a careful application of CAS to be used as a complementary tool for the carotid surgeon to use in special circumstances when CEA cannot be undertaken with acceptable morbidity. Furthermore, since the reported stroke morbidity rate of CAS exceeds the AHA recommendation for treatment of asymptomatic patients, most nonsurgical patients with asymptomatic disease should be treated with medical therapy.
Percutaneous Angioplasty and Stenting of Left Subclavian Artery Stenosis in Patients with Left Internal Mammary-Coronary Bypass Grafts: Clinical Experience and Long-Term Follow-up
Authors: Angle J. Fritz , Matsumoto Alan H. , McGraw J. Kevin , Spinosa David J. , Hagspiel Klaus D. , Leung Daniel A. , Tribble Curtis G.
Published: June 2007

The authors report their experience with percutaneous transluminal angioplasty (PTA) and stenting of the left subclavian artery (LSA) in patients with recurrent angina and a left internal mammary (LIMA)-coronary bypass graft or in patients who will be undergoing LIMA-coronary artery bypass grafting. From November 1990 to February 2001, 21 patients (1 1 men and 10 women) with significant left subclavian artery stenosis were treated; 18 patients had a prior LIMA bypass graft, and 3 patients were treated before coronary artery bypass surgery. Angiographic follow-up was performed in 12 patients and clinical follow-up was obtained in all patients. All lesions were atherosclerotic in etiology and located in the proximal left subclavian artery. The mean stenosis was 81% (range 50-100%). All patients initially underwent PTA. Stents were placed in 7 patients for suboptimal PTA results. Technical success was achieved in all patients. Pressure gradient measurements were available in 6 patients. Mean pretreatment gradient was 29 mm Hg (range, 10-50 mm Hg) and fell to 3 mm Hg (0-8 mm Hg) posttreatment. There were 2 minor and 2 major complications. The 30-day mortality rate was 9.5% (2 patients). The remaining 19 patients had clinical or angiographic follow-up of 4-68 months (mean, 27 months). Three patients were found to have recurrent stenoses by angiography 8-43 months after PTA and 3 more had clinical signs of recurrent stenosis. Therefore, the long-term clinical patency rate of LSA PTA and stent was 15 of 19 (79%). One was managed with bypass surgery, 1 with repeat PTA and stent placement, and 1 was managed conservatively. Therefore, the assisted patency was 15 of 19 (79%). Eleven of 19 (58%) of the patients in long-term follow-up had cardiac symptoms, but repeat angiography excluded recurrent LSA stenosis as the cause of their symptoms in 7 cases. Only 4/19 (2 1%) had cardiac symptoms potentially attributable to LSA restenosis. Four patients expired during follow-up, but 3 had no evidence of subclavian stenosis. PTA and stenting is an effective treatment of proximal left subclavian artery stenosis in patients who develop angina after a LIMA-coronary artery bypass, or in patients before a LIMA-CABG. Cardiac symptoms after LSA PTA and stent are most often due to progressive coronary artery disease rather than to recurrent LSA stenosis.
Surgery of the Superficial Venous System in Elderly Patients
Authors: Weinmann Eran E. , Poluksht Natan , Chayen David , Bass Arie
Published: June 2007

Chronic venous insufficiency, which traditionally has been attributed to failure of the deep venous system, may result from reflux in the superficial venous system. Chronic venous insufficiency is common in elderly patients, but surgical treatment is seldom offered to this patient population. We evaluated the results of superficial venous surgery for the treatment of severe chronic venous insufficiency in a cohort of elderly patients. The authors assessed patients aged 70 years or more with chronic venous insufficiency that had failed conventional conservative treatment. The superficial and deep venous systems were thoroughly investigated by duplex ultrasonography. Associated medical conditions were reevaluated and their treatment optimized. Twenty-eight patients (11 men, 17 women), aged between 70 and 89 years (mean 79), underwent superficial venous surgery. Open ulcers, active dermatitis and recurrent erysipelas were evident in 12, 9 and 7 patients, respectively. Limb swelling and severe pain were present in 25 (89%). The operations were performed under general or regional anesthesia with overnight hospitalization. Surgical treatment consisted of ligation of the points of reflux at the junctions of the superficial and deep systems, as defined by the duplex examination (21 saphenofemoral junctions, 5 saphenopopliteal junctions, 10 perforator veins), and stripping of the long saphenous vein to knee level (15 patients). Postoperative ambulatory treatment was continued until the wounds were completely closed. All ulcers healed completely within 8 weeks. No cardiac, respiratory, or renal complications were encountered. Wound infection at the groin occurred in 1 patient. Cellulitis of the calf area developed in 4 patients. Two ulcers recurred during follow-up of 1 to 5 years (mean 2.5). Surgery of the superficial venous system for treatment of severe chronic venous insufficiency is effective and can be achieved with minimal morbidity in selected elderly patients. The risk/benefit ratio for this procedure has been reduced sufficiently to ensure a major improvement in the quality of life of such patients.
Peroneal Artery Approach for Angioplasty of the Superficial Femoral Artery
Authors: Wolosker Nelson , Nakano Livio , Duarte Flavio Henrique , De Lucia Nelson , Leao Pedro Puech
Published: June 2007

The authors report the implantation of a Palmaz stent in the superficial femoral artery using an approach not previously described, the peroneal artery. A 64-year-old man was admitted with extensive necrosis of the right foot. Physical examination showed a normal right femoral pulse but absence of popliteal and tibial pulses. Arteriography showed a superficial femoral artery with critical stenoses but a normal profunda artery. A classic below-knee amputation was performed. During the procedure, the muscular blood flow was considered insufficient, by clinical experience, to achieve limb healing at this level, and so the surgeon chose to perform an angioplasty of the superficial femoral artery lesion, utilizing an access through the leg arteries. After introducing the guidewire through the peroneal artery, the surgeon successfully dilated the lesion and implanted a Palmaz stent. Afterward, the popliteal pulse became palpable in physical examination and improved the skin and muscular aspect in this level. The surgery was finished with a closed stump. The surgery healed satisfactorily, without any complications, and the patient had a satisfactory follow-up, with ambulatory rehabilitation, and recovery of walking capacity with a leg prosthesis. The peroneal approach gave satisfactory results and should be considered in clinical situations like this.
Prospects for the Medical Management of Abdominal Aortic Aneurysms
Authors: Steinmetz Eric F. , Buckley Celine , Thompson Robert W.
Published: June 2007

Abdominal aortic aneurysms (AAAs) are a chronic degenerative disease with life-threatening implications. While AAAs are thought to arise through a localized form of arterial wall injury superimposed on various predisposing factors, their natural history is one of progressive structural deterioration, gradual expansion, and eventual rupture. Pathologic processes contributing to the changes observed in AAAs include chronic inflammation, destructive remodeling of the extracellular matrix, and depletion of vascular smooth muscle cells. These changes result in progressive aortic dilatation accompanied by alterations in vessel geometry, redistribution of hemodynamic wall stresses, and diminished tensile strength. As outlined in this review, better understanding of the biological mechanisms underlying these changes will allow design of novel therapeutic strategies to suppress the process of aneurysmal degeneration.
Dichioroacetate Increases Skeletal Muscle Pyruvate Dehydrogenase Activity During Acute Limb lschemia
Authors: Wilson Jeffrey S. , Rushing Greg , Johnson Brad L. , Kline Jeffrey A. , Back Martin R. , Bandyk Dennis F.
Published: June 2007

The purpose of this study was to evaluate the effects of dichloroacetate sodium (DCA), a drug that inactivates pyruvate dehydrogenase kinase (PDH-K), on pyruvate dehydrogenase (PDH) activity, lactate level, and function of skeletal muscle in an experimental model of acute limb ischemia. Thirty-two male Sprague-Dawley rats underwent right iliac artery ligation to produce hindlimb ischemia. After 2 hours of ischemia, 16 animals received intravenous DCA (15 mg/i 00 g body weight) and 16 control animals received an equivalent volume of normal saline. After an additional 1 hour of ischemia (total 3 hours) tibialis anterior muscle from the ischemic limb and contralateral nonischemic limb was excised, rapidly freeze-clamped with Wallenberg tongs cooled in liquid nitrogen, and stored at -700C. Muscles specimens were subsequently assayed for PDH activity and lactate level by use of spectrophotometric techniques. An additional 16 animals (DCA-treated, n = 8; control, n = 8) underwent ex-vivo gastrocnemius muscle fatigue testing with a 10 g tension preload after 3 hours of limb ischemia. In ischemic hind limbs, DCA treatment significantly (p = 0.025) increased PDH activity (19.6 ±1.6 pmol/min/g dry weight) compared to controls (13.1 ± 1.3 pmol/min/g dry weight). DCA treatment did not increase (p = 0.13) skeletal muscle PDH activity in the nonischemic limbs (9.6 ± 1.1 umol/min/g dry weight, controls; 13.2 ±1.3 pmol/min/g dry weight, DCA group). In DCA-treated animals, hind limb ischemia resulted in no significant increase in muscle lactate levels compared to the nonischemic limb, while control animals demonstrated a significant (p = 0.005) elevation in lactate level in ischemic limbs compared to contralateral nonischemic limb. Ischemia induced a significant decrease in time to muscle fatigue in both DCA-treated and control animals (p=0.002 and 0.001, respectively). Time to muscle fatigue in DCA-treated animals was increased compared to controls (2.6 ±0.3 versus 2 ±0.6 minutes; p< 0.05) in ischemic limbs but was not significantly different in nonischemic limbs (DCA = 3.3 ±0.5 minutes; control = 3.1 ±0.6 minutes). Treatment with DCA during acute limb ischemia reduced the depression of PDH activity and lactate level of skeletal muscle. Ischemic muscle function was also improved by DCA treatment. Further investigation of the potential beneficial effects of DCA treatment on muscle injury during ischemia and reperfusion is warranted.
Relationship of Peripheral Arterial Compliance and Standard Cardiovascular Risk Factors
Authors: Willens Howard J. , Davis Warren , Herrington David M. , Wade Karen , Kesler Karen , Mallon Steve , Brown W. Virgil , Reiber J. H. C. , Raines Jeffrey K.
Published: June 2007

Abnormalities of peripheral arterial compliance are clinically useful markers of atherosclerosis and risk of vascular events. Local peripheral arterial compliance can be easily and accurately assessed in the clinic by computer-controlled pulse volume recordings (air plethysmography). The purpose of this study was to investigate the relationship between clinical cardiovascular risk factors, a surrogate of atherosclerotic burden, and peripheral arterial compliance in the thigh and calf determined by quantification of local pulse volume recordings in patients undergoing coronary angiography. Peripheral arterial compliance in the thigh and calf was measured in 346 patients undergoing diagnostic cardiac catheterization at 4 centers. Demographic and cardiovascular risk factor data were collected, and their relationship to local arterial compliance examined using a new device that assesses maximal local arterial volume change in an extremity segment. Pulse volume recordings detected decreased local arterial compliance in the thigh associated with a history of hypertension (p< 0.0001), diabetes mellitus (p = 0.0001), and hyperlipidemia (p = 0.0007). In the calf, this arterial compliance measure was associated with a history of hypertension (p < 0.0001) and diabetes mellitus (p = 0.002). Females had lower arterial compliance than males in the thigh (p = 0.003) and calf (p <0.0001). Limited evidence of lower arterial compliance in the thigh was found for those with obesity (p = 0.07). This procedure also demonstrated that subjects with multiple cardiovascular risk factors had lower arterial compliance in the thigh than subjects with no or 1 risk factor (p = 0.0001). Peripheral arterial compliance determined by air plethysmography is strongly associated with standard cardiovascular risk factors. The noninvasive measurement of local arterial compliance by regional pulse volume recording may be a useful adjunct for cardiovascular risk stratification early in the course of the disease as well as for monitoring vascular response to therapy.
Adjunctive Endovascular Techniques in the Management of Postoperative Carotid Artery Pseudoaneurysms - Useful Armamentarium for Vascular Surgeons
Authors: Terramani Thomas T. , Workman Michael J. , Loberman Zeev , Dawson David L. , Bush Ruth L. , Lumsden Alan B. , Lin Peter H.
Published: June 2007

Postoperative carotid artery pseudoaneurysms are rare. The traditional treatment of choice has been operative repair, which can present a significant technical challenge owing to the reoperative neck inflammation and potential cranial nerve injuries. The authors report 3 cases of postoperative carotid pseudoaneurysms that were successfully managed by use of various adjunctive endovascular techniques. The adjunctive endovascular maneuvers included the following: 1) endoluminal balloon placement for preoperative test occlusion and intraoperative proximal control to facilitate operative dissection in the first patient with a carotid pseudoaneurysm; 2) endoluminal stent-graft placement to exclude a large expanding carotid pseudoaneurysm in the second patient; and 3) endoluminal coil placement along with balloon occlusion to achieve complete hemostasis in the third patient, who presented with a hemorrhaging carotid pseudoaneurysm. Successful outcomes were achieved in all 3 patients by use of adjunctive endovascular techniques. These cases underscore the role of adjunctive endovascular treatment as an armamentarium for vascular surgeons in the treatment of complex carotid pseudoaneurysms.
Current Status of Intravascular Stents as Delivery Devices to Prevent Restenosis
Authors: Pearce Benjamin J. , McKinsey James F.
Published: June 2007

The acute technical success of percutaneous transluminal angioplasty (PTA) has been improved with the use of intravascular stents. However, stent placement has led to the development of an increased myointimal hyperplastic response leading to late reduction in vessel lumen. Restenosis (≥50% reduction in reference lumen diameter) rates for coronary angioplasty and stenting are reported between 20% and 50% at 1 year. Several studies are currently evaluating novel delivery of antiproliferative agents to prevent neointimal hyperplasia. The authors review the mechanism of neointimal hyperplasia as it relates to stent placement and discuss recent and ongoing trials evaluating intravascular brachytherapy and drug-eluting stent technology in the inhibition of restenotic lesions.
Saratin, an Inhibitor of Collagen-Platelet Interaction, Decreases Venous Anastomotic Intimal Hyperplasia in a Canine Dialysis Access Model
Authors: Smith Todd P. , Alshafie Tarek A. , Cruz Carlos P. , Fan Chun-Yang , Brown Aliza T. , Wang Yunfang , Eidt John F. , Moursi Mohammed M.
Published: June 2007

Prosthetic dialysis access thrombosis and/or stenosis is the most common cause of graft impairment or loss and is primarily attributed to venous outflow stenosis due to intimal hyperplasia. Intimal hyperplasia is thought to result from interactions between areas of exposed subendothelial collagen in an injured vessel and platelets, resulting in platelet adhesion. Saratin, an inhibitor of the WF-dependent binding of platelet to collagen interaction, has been shown in vitro to reduce the adhesion of platelets to collagen. In the current study, the authors inves-tigated the effects of topical saratin administration in a canine dialysis access model in regard to intimal hyperplasia development at the venous anastomosis. Fourteen female mongrel dogs underwent placement of a femoral polytetrafluoroethylene (PTFE) dialysis access graft and were placed into 1 of 2 groups: 1) control or 2) experimental with topical saratin application. The experimental group had 600,μg of saratin (1 μg/,μL) applied for 5 minutes directly onto the venous anastomosis before restoration of blood flow; control groups received vehicle control. At 4 weeks postoperative, a portion of the graft was removed along with a segment of the outflow vein. Veins were subsequently processed, sectioned, and analyzed along the length of the excised segment and divided into blocks that included the area of the graft toe, midanastomotic region and heel, and blocks A-E. Intimal hyperplasia was assessed by a computerassisted morphometric analysis. Platelet counts and bleeding times were also measured. Vein segments in the control group (n= 7) showed pronounced intimal hyperplasia in blocks B, C, and D as compared to the saratin group (n = 6). Distribution of intimal hyperplasia by blocks between control and saratin groups were as follows: block [A] 8.6 ±1.9 vs 9.7 ±3.0% (p = NS), [B] 32.7 ±6.3 vs 10.7 ±3.5% (p=0.01), [C] 44.8 ±6.2% vs 10.3 ±1.5% (p=0.0004), [DI 40.8 ±1 1.0 vs 9.1 ±4.2% (p = 0.02), [E] 7.5 ±5.5 vs 2.7 ±0.4% (p = NS). Intimal hyperplasia normalized to vein wall thickness also showed a significant reduction with saratin application. Bleeding times and platelet counts obtained at different time points during the experiment showed no difference between control and saratin groups. In a canine dialysis access model using PTFE grafts, topical application of saratin at the venous anastomosis decreased intimal hyperplasia development by as much as 77% when compared with control animals. Saratin provides for a method of substantially reducing intimal hyperplasia by direct local application without systemic side effects.
Isolated Abdominal Aortic Rupture in a Child due to All-Terrain Vehicle Accident
Authors: Lin Peter H. , Barr Virginia , Bush Ruth L. , Velez Daniel A. , Lumsden Alan B. , Ricketts James
Published: June 2007

Rupture of the abdominal aorta as the result of blunt trauma is uncommon, due in part to its protected position in the retroperitoneum. Isolated aortic rupture following blunt injury is even more rare. A case of isolated abdominal aortic rupture in a 6-year-old girl following blunt trauma due to an all-terrain vehicle accident is reported. The girl survived following an emergent aortoiliac reconstruction.
Bilateral Lower Extremity Gangrene Requiring Amputation Associated with Heparin-Induced Thrombocytopenia
Authors: Dickinson Brian P. , De Ugarte Daniel A. , Reil Todd D. , Beseth Bryce D. , Lawrence Peter F.
Published: June 2007

Heparin use, both prophylactically and therapeutically, is prevalent among hospitalized patients. Patients on heparin may develop a thrombocytopenia that is self-limited. Fewer patients develop a heparin-induced thrombocytopenia that can cause severe bleeding and thrombosis owing to intravascular platelet aggregation. The authors present a case report of heparininduced thrombocytopenia in a patient who underwent aortic arch and aortic valve replacement that resulted in bilateral above-knee amputations. The patient developed limb ischemia related to heparin-associated thrombosis, but had a delay in antibody seroconversion. Early and accurate diagnosis of heparin-induced thrombocytopenia requires a high clinical suspicion and may be present despite the absence of serum antibodies.
Expert Witness Testimony: Rules of Engagement
Authors: Satiani Bhagwan
Published: June 2007

Overlooked in most legislative remedies to address the medical malpractice (MMP) crisis is stringent prohibition against the use of “junk science” in the courtroom and defining the qualifications of an expert witness. Expert witnesses should be required to: (1) to disclose information materially related to the reliability of expert testimony. (2) Filing of a “Daubert brief”: a summary of the plaintiff’s expert’s opinion along with a resume outlining his/her knowledge, skill, experience, training and education, reputation in the field relevant to the litigation, and complete details of the methodology employed by the expert. (3) An oath or declaration that acknowledges the duty to disclose to the court all information known to the person to be material to the reliability of the expert witness. Rules of evidence: The “Frye test” or the “general acceptance rule” has been used by judges to exclude expert testimony unless it is “sufficiently established to have gained general acceptance in the particular field in which it belongs.” Stricter standards need to be legislated at the state level. The mandatory use of scientific panels by judges in all MMP cases is needed. Legislative relief has been sought by the medical community to address the serious disconnect between negligence and MMP litigation. The use of junk science in the courtroom remains largely unaddressed in the judicial system. Medical societies and legislatures must act to define an expert witness and restrain plaintiff’s attorneys from using junk science to influence juries.
Entrapment of a Cerebral Embolic Protection Device
Authors: Shilling Kimberly , Uretsky Barry F. , Hunter Glenn C.
Published: June 2007

Cerebral protection devices have significantly reduced the incidence of embolic events in patients undergoing carotid stenting. With the increasing availability of such devices an awareness of the potential complications associated with their deployment is essential. Here we report a patient with entrapment of a filter device within a carotid stent that required surgical removal. The mechanisms underlying this complication and measures to prevent its occurrence are discussed.
Platelet Function and Pharmacologic Inhibition
Authors: Chaer Rabih A. , Graham Joseph A. , Mureebe Leila
Published: June 2007

Platelets have traditionally been understood within the context of hemostasis and hemorrhagic disorders. However, with increasing procedures being performed in smaller vessels and with an increasing incidence of atherosclerosis, the often critical role platelets play is more evident. Platelets are no longer viewed as “scaffolding” for the events of the coagulation cascade but rather as important catalysts in hemostasis, thrombosis, and fibrinolysis. Improved understanding of platelet physiology has led to developments of pharmacologic adjuncts resulting in improved patency rates and improved patient outcomes. This review addresses the physiology of platelet function and the impact of new pharmacologic agents in percutaneous intervention.
The Use of Covered Nitinol Stents to Salvage Dialysis Grafts After Multiple Failures
Authors: Naoum Joseph J. , Irwin Chance , Hunter Glenn C.
Published: June 2007

The increasing number of patients requiring hemodialysis and the limited number of access sites have resulted in an increase in multiple graft revisions to maintain access for hemodialysis. Venous outflow or anastomotic stenoses in vascular grafts tend to recur and contribute to the difficulty in maintaining a functioning graft. Thus, extending the life of a failed graft becomes an important objective of this study, which was to assess the use of covered nitinol stents to salvage expanded polytetrafluoroethylene (ePTFE) grafts with venous anastomotic or outflow stenosis that have failed after multiple revisions. This is a review of 8 failed nonautogenous ePTFE grafts with isolated venous anastomotic or proximal outflow stenoses that had undergone multiple previous revisions, had failed percutaneous transluminal angioplasty (PTA), and required placement of a covered nitinol stent. Graft locations were forearm (2), upper arm (4), and femoral (2). The mean number of interventions per patient before stent placement was 5.87 thrombectomies (range 2–28) and 3.38 balloon angioplasties (range 2–19). Five patients had 0.62 interposition grafting and 3 had patch angioplasty. All 8 patients (100%) underwent successful dialysis after thrombectomy and stenting. The primary and secondary patency rates after stent placement were 50% and 75%, and 25% and 75%, at 3 and 6 months, respectively. Percutaneous thrombectomy, balloon angioplasty, and concomitant covered nitinol stent placement extend the function of hemodialysis access grafts that have previously failed multiple times.
Operative Management of an Aberrant Splenic Artery Aneurysm: Utility of the Medial Visceral Rotation Approach
Authors: LaBella Gennaro D. , Muck Patrick , Kasper Gregory , Welling Richard , Schlueter Frank , Vaughan Aislinn
Published: June 2007

The authors report an unusual case of a splenic artery aneurysm arising off the superior mesenteric artery. This was an incidental finding on computed tomography scan found during evaluation for a different or a separate disease process.
Use of Parietal Peritoneum for Aortic Stump Coverage Following Removal of an Infected Aortic Prosthesis
Authors: Ly Truc , Zhou Wei , Bush Ruth L. , Lumsden Alan B. , Lin Peter H.
Published: June 2007

Aortic graft infections, albeit rare, pose a significant treatment challenge. Aortic stump disruption, in particular, is a potentially devastating complication. We describe a novel technique of using the parietal peritoneum to bolster a friable aortic stump in a 56-year-old man after an infected aortobifemoral graft was removed. The parietal peritoneal pedicle, in our experience, provides an effective alternative to reinforce an aortic stump when conventional coverage options have been exhausted.