Critical shoulder angle does not influence retear rate after arthroscopic rotator cuff repair.

PURPOSE: The critical shoulder angle (CSA) has been implicated as a potential risk factor for failure following arthroscopic rotator cuff repair (RCR). However, there is conflicting evidence regarding the clinical usefulness of this measurement. Given these discrepancies and limited comparisons to clinical outcomes, the aim of the current study was to determine whether higher CSAs correlated with an increased retear rate after arthroscopic rotator cuff repair and to determine if any association between CSA and patient-reported outcomes (PROs) exists. It was hypothesized that there would be no correlation between CSA and retear rate or PROs after arthroscopic rotator cuff repair. METHODS: A total of 164 patients who underwent arthroscopic RCR were retrospectively reviewed. CSA was measured for each patient. Patients were then divided into a retear group of 18 patients and a non-retear group of 146 patients. Patient-reported outcomes (PROs), including PROMIS 10 score, American Shoulder and Elbow Surgeons (ASES) score, Brophy score, and visual analog pain scores (VAS) were recorded post-operatively. RESULTS: The average CSA was 31.2 ± 4.5° for the retear group and 32.2 ± 4.7° for the non-retear group (n.s.). No correlations were found between CSA and PROMIS score (n.s.), ASES score (n.s.), Brophy score (n.s.), or VAS (n.s.). CONCLUSION: Critical shoulder angle had no correlation to retear rate or patient-reported outcomes. CSA should not be used as a clinical predictor to assess rotator cuff retear risk after arthroscopic RCR. LEVEL OF EVIDENCE: Level III.

Effective management of severe cutaneous mastocytosis in young children with omalizumab (Xolair® ).

Omalizumab (Xolair® ) is an anti-IgE monoclonal antibody, which may benefit adults with systemic mastocytosis. We report effective treatment with omalizumab in two toddlers with severe diffuse cutaneous mastocytosis. Our cases offer preliminary evidence to support the safe use of omalizumab in paediatric patients with cutaneous mastocytosis.

Activated STING in a vascular and pulmonary syndrome.

BACKGROUND: The study of autoinflammatory diseases has uncovered mechanisms underlying cytokine dysregulation and inflammation. METHODS: We analyzed the DNA of an index patient with early-onset systemic inflammation, cutaneous vasculopathy, and pulmonary inflammation. We sequenced a candidate gene, TMEM173, encoding the stimulator of interferon genes (STING), in this patient and in five unrelated children with similar clinical phenotypes. Four children were evaluated clinically and immunologically. With the STING ligand cyclic guanosine monophosphate-adenosine monophosphate (cGAMP), we stimulated peripheral-blood mononuclear cells and fibroblasts from patients and controls, as well as commercially obtained endothelial cells, and then assayed transcription of IFNB1, the gene encoding interferon-ß, in the stimulated cells. We analyzed IFNB1 reporter levels in HEK293T cells cotransfected with mutant or nonmutant STING constructs. Mutant STING leads to increased phosphorylation of signal transducer and activator of transcription 1 (STAT1), so we tested the effect of Janus kinase (JAK) inhibitors on STAT1 phosphorylation in lymphocytes from the affected children and controls. RESULTS: We identified three mutations in exon 5 of TMEM173 in the six patients. Elevated transcription of IFNB1 and other gene targets of STING in peripheral-blood mononuclear cells from the patients indicated constitutive activation of the pathway that cannot be further up-regulated with stimulation. On stimulation with cGAMP, fibroblasts from the patients showed increased transcription of IFNB1 but not of the genes encoding interleukin-1 (IL1), interleukin-6 (IL6), or tumor necrosis factor (TNF). HEK293T cells transfected with mutant constructs show elevated IFNB1 reporter levels. STING is expressed in endothelial cells, and exposure of these cells to cGAMP resulted in endothelial activation and apoptosis. Constitutive up-regulation of phosphorylated STAT1 in patients' lymphocytes was reduced by JAK inhibitors. CONCLUSIONS: STING-associated vasculopathy with onset in infancy (SAVI) is an autoinflammatory disease caused by gain-of-function mutations in TMEM173. (Funded by the Intramural Research Program of the National Institute of Arthritis and Musculoskeletal and Skin Diseases; ClinicalTrials.gov number, NCT00059748.).

Public perceptions of the role of Australian pharmacists in cardiovascular disease.

BACKGROUND AND OBJECTIVE: To assess the public's perception of pharmacists' involvement and role in cardiovascular disease prevention and management. METHODS: A computer-assisted telephone interview of 505 households was conducted. The survey was administered to metropolitan, rural and remote residents over the age of 30 years. The interview had questions on the patient's general satisfaction with the quality of service provided by their regular community pharmacy, including factors such as location, professionalism, prices, product range and knowledge of the staff. The participants were asked if they thought pharmacists were capable of providing screening, testing and drug prescribing services for blood pressure and cholesterol, and how likely they would be to use these services through a pharmacy. The interview also included questions on how likely this person would be to seek advice on lifestyle changes and medications from various health professionals, including pharmacists. RESULTS: The majority (97%) were satisfied with the service provided at their regular pharmacy. Those surveyed agreed or strongly agreed that pharmacists are capable of providing screening or testing for raised blood pressure (52%) and diabetes (51%), with a minority (38%) agreeing that pharmacists are capable of testing for raised cholesterol. The pharmacist's role with perceived highest capability by those surveyed was in providing advice on how to take medicines properly, with 90% of respondents willing to seek this advice from their pharmacist. A limited role by pharmacists was seen in the diagnosis of CVD and prescribing medications. In relation to the prevention of CVD, even though 76% of respondents believed that pharmacists are capable of providing advice on lifestyle changes (e.g. weight loss, smoking and alcohol intake), only 8% of current or past smokers had sought assistance to give up smoking at their pharmacy and while 69% of all respondents had sought help with weight control, only 3% of these had looked towards their pharmacy for assistance. CONCLUSION: There was belief by those Australians surveyed that community pharmacists are capable of providing screening for hypertension and diabetes. Through these services and in conjunction with counselling on CVD risk reduction, pharmacists may play an important role in the reduction of CVD, ultimately improving public health and decreasing the burden on Australia's health care system. However, at present pharmacists are not being fully utilized to deliver health promotion advice and contribute to the prevention of CVD.

Warm storage of whole blood for 72 hours.

BACKGROUND: In field emergency medicine, fresh whole-blood units are stored at room temperature up to 24 hours or occasionally longer. Few data exist on the integrity and in vitro functional properties of whole blood stored warm beyond 24 hours. STUDY DESIGN AND METHODS: Ten citrate phosphate dextrose solution whole-blood units were collected and divided into two equal volumes. One-half of each unit was stored at 19 degrees C and the other half was stored at 25 degrees C, encompassing the accepted range for room temperature storage. At 6, 24, 48, and 72 hours, aliquots were collected from each unit and whole blood analyzed for cell counts, gases, and clotting function with thromboelastography, red cells for intracellular analytes, platelet (PLT)-rich plasma for aggregometry, and the supernatant for hemoglobin, potassium, glucose, lactate, and plasma clotting studies. RESULTS: Whole-blood units stored at room temperature maintained cellular counts and coagulation activity for up to 72 hours. Units stored at 19 degrees C demonstrated greater RBC adenosine triphosphate and 2,3-diphosphoglycerate (DPG) content and stronger responses in PLT aggregation studies when compared with 25 degrees C storage. No significant hemolysis was observed, and no bacterial growth was detected. CONCLUSION: Storage of whole blood at room temperature for 72 hours leads to marked reductions in pH and DPG, but the observed reduction in PLT function and plasma coagulation factor activity was surprisingly modest compared to literature values. These findings should prompt additional investigation, given their potential importance for whole blood processing and field-expedient transfusion.

Preimplant vein intimal thickness is not a predictor of bypass graft stenosis.

PURPOSE: Preimplant vein morphology has been implicated as a risk factor for subsequent vein graft failure. It is controversial whether microscopic intimal thickening in random saphenous vein biopsy specimens is associated with an increased risk of graft failure. The purpose of this study was to determine the incidence of preexisting intimal thickening in a macroscopically normal preimplant vein, and to evaluate whether preimplant vein intimal thickness was predictive of future vein graft stenosis. METHODS: As part of an ongoing protocol, samples of preimplant veins were obtained at the time of the primary leg bypass. Routine duplex surveillance identified 14 patients who required operative revision for severe graft stenosis (n = 12) or graft occlusion (n = 2). Verhoeff's staining of specimens was performed to delineate the internal elastic lamina. Morphometric analysis of preimplant vein specimens was performed. The results were compared to a control group of 13 preimplant vein specimens selected from patients whose grafts have remained patent and stenosis-free by duplex. RESULTS: Preoperative risk factors were identical between the two groups. Mean intimal thickness in all 27 specimens was measured by two blinded observers. Almost 50% of specimens exhibited marked intimal thickening (>0.08 mm). The mean preimplant intimal thickness of the stenosis group was 0.108 mm +/- 0.155 compared to 0.100 mm +/- 0.064 for the control group (P = 0.866, NS). CONCLUSION: Although grossly normal preimplant veins often exhibit prominent microscopic intimal thickening, preimplant vein intimal thickness determined from a random saphenous vein biopsy at the time of primary leg bypass is not predictive to the subsequent development of vein graft stenosis.

The natural history of intermediate and critical vein graft stenosis: recommendations for continued surveillance or repair.

OBJECTIVE: Duplex ultrasound surveillance (DUS) after autogenous lower extremity bypass grafting is controversial. Specific criteria mandating graft revision are not uniform. It has been suggested that grafts harboring critical stenoses undergo revision, whereas those with intermediate stenoses undergo arteriography with selective repair. We sought to define the natural history and determine the risk of graft occlusion associated with unrepaired vein graft stenoses. METHODS: We analyzed serial vascular laboratory and clinical data of 156 autogenous infrainguinal vein grafts in 142 patients. Grafts were categorized into three groups according to the first DUS-detected (index) lesion: (1) normal (peak systolic velocity [PSV] < 200 cm/s, velocity ratio [V(r)] < 2); (2) intermediate stenosis (200 cm/s < PSV < 300 cm/s, 2 < V(r) < 4); and (3) critical (PSV > 300 cm/s, V(r) > 4). Our policy was to repair grafts with critical lesions and monitor all others. The risks of stenosis progression, graft revision, and graft thrombosis for each group were compared. RESULTS: Serial DUS was normal in 100 (64%) grafts. The incidence of graft thrombosis in the normal group was 3% per year (mean follow-up, 27.5 months). Intermediate lesions developed in 32 grafts (20%) and were followed. Among these 32 grafts with intermediate stenoses, 63% progressed to critical and were revised, and 32% resolved or stabilized (mean follow-up, 26 months). Only one graft occlusion occurred in grafts with intermediate lesions subjected to serial DUS monitoring (incidence 1.5% per year, P = not significant). In the third group, 16 of 25 grafts with critical lesions were successfully revised and remain patent. In nine cases, critical lesions were not repaired, resulting in seven (78%) occlusions, all within 4 months of DUS detection. CONCLUSIONS: Serial surveillance is safe and effective for grafts with intermediate stenoses. The graft occlusion rate for such grafts with careful monitoring is no different from grafts without stenosis, and therefore, arteriography is not indicated in the absence of progression to critical stenosis. The short-term risk of graft occlusion in the presence of an unrevised critical stenosis is nearly 80%. These data have important clinical implications concerning the natural history of vein graft lesions.

Improved patency of infrainguinal polytetrafluoroethylene bypass grafts using a distal Taylor vein patch.

OBJECTIVE: The purpose of this study was to evaluate graft patency and limb salvage rates for infrainguinal polytetrafluoroethylene (PTFE) bypass grafts using distal anastomotic Taylor vein patch in patients lacking suitable vein conduit. METHODS: We reviewed 44 patients who underwent infrainguinal bypass between January 1996 and August 2000 using 6-mm PTFE and a distal Taylor vein patch. Postoperative oral anticoagulation was administered to 80% of patients. Graft patency was confirmed during follow-up with serial graft duplex scanning. RESULTS: Operative indications were rest pain, nonhealing ulcer, or gangrene in 76% of patients, 43% of whom had undergone previous ipsilateral leg bypass. Distal anastomotic sites were the below-knee popliteal (29%) and tibial-peroneal arteries (67%). At 1 month, 1 year, and 2 years, respectively, the primary patencies (SE <10%) were 86%, 71%, and 71%; limb salvage rates were 95%, 75%, and 66%; and mortality rates were 5%, 20%, and 20%. CONCLUSIONS: These early results with PTFE and distal Taylor vein patch are promising, and markedly superior to previous reports of PTFE without anastomotic modification. Further long-term follow-up will be necessary to determine the 3- to 5-year durability of such reconstructions.

The influence of gender on complications of carotid endarterectomy.

PURPOSE: Carotid endarterectomy (CEA) effectively reduces stroke risk in properly selected patients. Subgroup analysis of the Asymptomatic Carotid Artery Study trial noted increased complications in women. Additional studies implicate female gender as a risk factor for perioperative stroke, leading some clinicians to modify the indications for CEA in women. The purpose of this study was to determine the influence of gender on the risk of perioperative complications in patients undergoing CEA. METHODS: The records of all patients who underwent CEA at a university medical center from January 1995 to December 1999 were reviewed. Patient demographics, procedure related risk factors, operative details, and specific complications were entered into a database for statistical analysis. RESULTS: A total of 324 consecutive patients underwent CEA during the study period. There were 199 men (61%) and 125 women (39%). Among the men and women, there were no differences in age, smoking, hypertension, hypercholesterolemia, diabetes, family history, renal insufficiency, or symptomatic versus asymptomatic indications for CEA. More women than men received a carotid patch (90.4% versus 77.9%, P = 0.003). One woman died (0.8%) and no men died for a total combined 30-day mortality of 0.31% (P = not significant). Men and women did not differ in rates of stroke (1.5% versus 2.4%) or perioperative myocardial infarction (1.0% versus 0.8%). In addition, there was no difference when stroke and death rates were combined (2% versus 3.2%). The length of stay (2.2 versus 2.6 days) was also not different. CONCLUSIONS: There are no significant differences in rate of stroke, myocardial infarction, or 30-day mortality, between men and women following CEA. Women should not be excluded from the benefits of CEA based on perceived increased complication rates.

An economic appraisal of lower extremity bypass graft maintenance.

OBJECTIVE: Infrainguinal graft surveillance leads to intervention on the basis of duplex-identified stenoses. We have become increasingly concerned about the high frequency with which such revisions are required to maximize graft patency and limb salvage rates. The economic implications of these procedures have not been carefully analyzed or justified. METHODS: We retrospectively reviewed 155 consecutive autogenous infrainguinal bypass grafts performed for chronic leg ischemia in 141 patients. All patients were enrolled in a prospective surveillance program using color flow duplex imaging. Full economic appraisal (cost analysis, cost-effect analysis, and cost-benefit analysis) was performed for all graft surveillance and limb salvage-related interventions through use of standard accounting and valuation techniques. RESULTS: Mean follow-up was 27 months. Five-year assisted primary patency (72%) and limb salvage rates (91%) were calculated by means of life table analysis. A total of 61 grafts required 86 revisions. Within 1 year of implantation, 36% of the grafts required revision. During this first year, the mean cost per graft enrolled was $9417. Time intervals after the initial year demonstrated a reduced annual revision rate (6%) and cost ($1725 per graft). The mean 5-year cost of graft maintenance ($16,318) approached that of the initial bypass graft ($19,331). The sum of the initial cost of bypass graft and 5-year graft maintenance cost ($35,649) was similar to the cost of amputation ($36,273). Grafts revised for duplex-detected stenoses (n = 46), in comparison with those revised after thrombosis (n = 15), had an improved 1-year patency (93% vs 57%; P <.01), required fewer amputations (2% vs 33%; P <.01), less frequently required multiple graft revisions (P =.06), and generated fewer expenses (at 12 months after revision, $17,688 vs $45,252, P <.01). CONCLUSION: The cost associated with graft maintenance is significant, particularly within the first year, and demands consideration. Revision of a duplex-identified stenosis was significantly less costly than revision after graft thrombosis. Compared with the cost of limb amputation, limb salvage-related expenses appear to be justified.

The correlation of early flow disturbances with the development of infrainguinal graft stenosis: a 10-year study of 341 autogenous vein grafts.

PURPOSE: Although duplex surveillance of infrainguinal bypass grafts is widely accepted, the optimal frequency and intensity of graft surveillance remains controversial. Earlier reports have suggested that grafts can be stratified into high-risk and low-risk groups based on the presence or absence of early graft flow disturbances. The purpose of this study was to provide long-term data in determining whether early graft flow disturbances detected by means of duplex scanning can predict the development of intrinsic vein graft stenosis. METHODS: We reviewed a series of patients undergoing prospective duplex graft surveillance after autogenous infrainguinal bypass grafting procedures from 1987 to 1997. Patients included in the study underwent at least one duplex scan within 3 months of graft implantation and were observed for a minimum of 6 months. Grafts were categorized as abnormal when a focal flow disturbance with a peak systolic velocity greater than 150 cm/s was identified within 3 months of graft implantation. RESULTS: Of 341 vein grafts in 296 patients who met inclusion criteria, 89 grafts (26%) required revision for intrinsic stenosis; the mean follow-up period was 35 months (range, 6 months to 10 years). Early flow disturbances were detected in 84 (25%) grafts. Grafts with early flow disturbances were more likely to ultimately require revision (43% vs 21%; P =. 0001) and required initial revision earlier (8 months vs 16 months; P =.019). Eighty-two percent of initial graft revisions occurred in the first 2 postoperative years; 69% occurred in the first year. However, an annual 2% to 4% incidence of late-appearing graft stenosis persisted during long-term follow-up. An additional 24 patients (7% of grafts) required an inflow or outflow reconstruction. CONCLUSION: Grafts with early postoperative flow disturbances detected by means of duplex scanning have nearly three times the incidence of graft-threatening stenosis and an earlier requirement for revision, when compared with normal grafts. This suggests that the biology and etiology of these lesions may differ. These data support not only aggressive efforts to detect early graft lesions to stratify grafts at highest risk, but also continued lifelong graft surveillance to detect late-appearing lesions, inflow and outflow disease progression, and maximize graft patency.

Symptomatic anterior uveitis in HIV-positive patients.

Symptomatic anterior uveitis is rare in HIV-positive patients. The uveitis associated with cytomegalovirus retinitis (CMVR), the commonest ocular manifestation in AIDS patients, is rarely symptomatic and patients do not typically present with a red painful eye in conjunction with blurred vision. In this article we report 12 cases of symptomatic anterior uveitis in HIV-positive patients and discuss the aetiology. The case notes of all HIV-positive patients presenting to the eye department with symptoms of uveitis over a 4-year period were studied retrospectively. The notes were analysed for age, sex, race, risk factors of HIV, features of the uveitis, concurrent disease and CD4 counts. Only 12 patients were identified to have symptomatic uveitis out of a total 172 patients. There were 9 males and 3 females with an average age of 35 years. None of these patients were taking either rifabutin, protease inhibitors or cidofovir. Seven out of the 12 patients had granulomatous uveitis. Of these 7 patients, 4 had CD4 counts over 200 and no other concurrent illness whilst 3 patients, with CD4 counts between 130-200, were subsequently found to have an underlying aetiology namely lymphoma, tuberculosis and candida. The remaining 5 patients, all with CD4 counts below 40, had a history of systemic illness with herpes zoster preceding the onset of the uveitis. HIV-positive patients with symptoms of uveitis do not have active CMVR and the ophthalmologist must search for other causes such as tuberculosis or lymphoma in those with granulomatous uveitis or herpes zoster in those with non-granulomatous uveitis. The CD4 count may be helpful.

Treatment of patients with venous thromboembolism and malignant disease: should vena cava filter placement be routine?

PURPOSE: It has been proposed that inferior vena cava filter placement should be the initial treatment of deep venous thrombosis (DVT) or pulmonary embolus (PE) in patients with coexisting malignant disease. We have chosen instead to selectively place filters only in patients with either a contraindication to anticoagulation therapy or a subsequent complication from anticoagulation therapy. The treatment efficacy and mortality rates in patients with concomitant malignant disease and venous thromboembolism using this approach was determined. METHODS: We retrospectively reviewed all patients at our institution with malignant disease in whom venous thromboembolism developed between August 1991 through August 1996 and identified 166 patients with PE (n = 8), DVT (n = 147), and DVT/PE (n = 11). Of these patients, 138 (83.1%) were initially treated with anticoagulation therapy, and 28 (16.9%) had primary filter placement because of contraindications to anticoagulation therapy (10 for intracranial tumors, 11 for recent or upcoming operations, 6 for recent hemorrhage, and 1 for a malignant bloody pericardial effusion). RESULTS: Thirty-two (23%) of the 138 patients who initially underwent anticoagulation therapy subsequently required a filter for the following reasons: bleeding (n = 15, 10.9%); recurrent thromboembolism (n = 6, 4.3%); heparin-induced thrombocytopenia (n = 1, 0.7%); and perceived high risk for bleeding with continued anticoagulation therapy (n = 11, 8%). Both bleeding and recurrent thromboembolism developed in 1 patient. Sixty patients (36%) received filters. No major technical complications occurred from filter placement. Major recurrent thromboembolic complications developed in 10 patients: DVT (n = 6, 10%), PE (n = 2, 3.3%), inferior vena cava thrombosis and phlegmasia cerulea dolens (n = 1, 1.7%), superior vena cava thrombosis (n = 1, 1.7%). Venous gangrene developed in 1 patient with DVT. The 1-year actuarial survival rates for patients treated with filter and anticoagulation therapy were 35% and 38%, respectively (P = NS). CONCLUSION: In summary, our experience suggests that 64% of patients with malignant disease and venous thromboembolism are effectively treated with anticoagulation alone; 17% require primary filter placement for standard indications, and an additional 19% require subsequent filter placement because of complications (primarily bleeding) or failure of anticoagulation therapy. Although technical complications of filter placement are low, serious life-threatening or limb-threatening thromboembolic complications developed in 17% of patients. Survival was poor in all patients, regardless of treatment. These data support a conservative approach of routine anticoagulation therapy with selective filter placement.

Finding DNA regulatory motifs within unaligned noncoding sequences clustered by whole-genome mRNA quantitation.

Whole-genome mRNA quantitation can be used to identify the genes that are most responsive to environmental or genotypic change. By searching for mutually similar DNA elements among the upstream non-coding DNA sequences of these genes, we can identify candidate regulatory motifs and corresponding candidate sets of coregulated genes. We have tested this strategy by applying it to three extensively studied regulatory systems in the yeast Saccharomyces cerevisiae: galactose response, heat shock, and mating type. Galactose-response data yielded the known binding site of Gal4, and six of nine genes known to be induced by galactose. Heat shock data yielded the cell-cycle activation motif, which is known to mediate cell-cycle dependent activation, and a set of genes coding for all four nucleosomal proteins. Mating type alpha and a data yielded all of the four relevant DNA motifs and most of the known a- and alpha-specific genes.

A regional pedal ischemia scoring system for decision analysis in patients with heel ulceration.

PURPOSE: The objective of this study was to evaluate patients undergoing operative debridement for heel ulceration and to categorize pedal perfusion and its influence on therapeutic alternatives. METHODS: Patients with heel ulceration were stratified by arteriography and graded I (patent posterior tibial, PT), II (occluded PT/reconstituted from peroneal), III (PT reconstituted from dorsal pedal), IV (no PT reconstitution but visible heel tributaries), and V (avascular heel). RESULTS: From May 1992 through January 1997, 23 patients underwent operative treatment for 25 heel ulcers. The heel ischemia score stratified patients into two groups: 1, revascularization/debridement (71% grades I to III, 29% grade IV, 0% grade V); and 2, free tissue transfer with or without revascularization (100% grades IV, V). Cumulative functional limb salvage was 91% (BP), 60% (BP + TT), and 81% (TT) at 24 months (P = 0.15 log rank). CONCLUSION: The heel ischemia score may direct treatment of heel ulceration by identifying patients who will need vascularized tissue transfer early in their treatment regimen.

Banana Die-Back Virus - a New Virus Infecting Banana in Nigeria.

Two viruses naturally infect Musa in Nigeria: banana streak badnavirus (BSV) and cucumber mosaic cucumovirus (CMV). During a recent field survey at Ibadan (Nigeria), some severely stunted banana plants (cv. Valery) were found that tested negative for CMV, banana bunchy-top virus, and BSV. The plants had symptoms of leaf crinkling, leaf necrosis, and cigar-leaf die-back. Subsequent suckers from the same mats were progressively more stunted. A 28- to 30-nm isometric virus was purified, and used for the production of antibodies, from the affected plants with (NH4)2SO4 to precipitate the virus. The antiserum (titer of 1:10,000) was used in enzyme-linked immunosorbent assay and immunosorbent electron microscopy to detect the virus. Mechanical inoculation with partially purified virus preparations resulted in stunting and development of pinpoint chlorotic lesions on Vigna unguiculata TVu-76 and symptomless systemic infection of Nicotiana occidentalis. The virus was not mechanically transmissible from N. occidentalis to banana. A serological relationship between this virus, banana die-back virus (BDBV), and tobacco ringspot, tomato ringspot, and cacao necrosis nepoviruses was found. The nematode species around the affected banana plants were isolated: Helicotylenchus multicinctus (Cobb) Golden was the dominant species, low numbers of H. dihystera (Cobb) Sher were present, but no virustransmitting nematodes were found in soil or banana roots. Further studies are needed to determine the mode of spread of BDBV, the implications for banana/plantain production in sub-Saharan Africa, and the safe international movement of germplasm.

Vein patching reduces neointimal thickening associated with prosthetic graft implantation.

PURPOSE: Modified anastomotic techniques utilizing autogenous vein-cuffs or patches have been devised with the hope of improving prosthetic graft patency. The mechanisms of the presumed improvement in patched anastomoses have never been elucidated and remain speculative. We characterized the healing response of the Taylor vein patch in prosthetic arteriovenous fistulae in a canine model of intimal hyperplasia. METHODS: Six adult dogs underwent placement of bilateral (6 patched, 6 control) 4-mm diameter expanded polytetrafluoroethylene loop femoral artery-vein fistulae. Serial duplex ultrasound examinations confirmed graft patency until explant at 6 weeks. Differential light microscopy with computerized image analysis was performed on serial 5-microm sections. Intimal thickness through the venous anastomosis and outflow veins of Taylor patch and control (nonpatched) grafts were compared. Cell type-specific immunocytochemical antibody stains for smooth muscle cells (alpha SMC actin) and endothelial cells (von Willebrand factor) were performed. RESULTS: Eleven of 12 grafts remained patent for 6 weeks, 1 control graft thrombosed. Mean duplex-derived peak systolic velocities of patched (96 cm/sec) and control (108 cm/sec) grafts were similar. Microscopy revealed more intimal pannus anastomotic suture line ingrowth in controls (mean thickness = 178 microm) than Taylor patched grafts (mean 147 microm, p = 0.0002). Significantly less intimal thickening was present in the outflow vein of patched (mean thickness = 90 microm) versus control grafts (mean 195 microm, P <0.0001). The intima maintained a single cell layer of vWF + endothelial cells, while the majority of the cells comprising the lesion expressed alpha SMC actin. CONCLUSION: Perianastomotic pannus is primarily composed of intimal smooth muscle cells. Neointimal thickening is significantly reduced in prosthetic arteriovenous fistulae created with the Taylor vein patch in a canine model. Reduction in perianastomotic intimal thickening may explain the reported clinical improvement in prosthetic bypass graft patency when modified with vein patch techniques.

Identification of predictors for lower extremity vein graft stenosis.

BACKGROUND: The cause of intrinsic vein graft stenosis, which develops in at least 20% of infrainguinal autogenous bypass grafts during the intermediate follow-up interval, is unknown. We performed standard duplex surveillance of all lower extremity bypass grafts and evaluated the potential of comorbid patient risk factors that might predict development of vein graft flow disturbance or high-grade graft stenosis. METHODS: Patients with at least 6 months of postoperative duplex surveillance were identified through our vascular registry. The association of clinical and hemodynamic profiles of graft performance were compared with specific patient risk factors, including demographics, cigarette smoking, antihypertensive medical therapy, type and quality of conduit, degree of ischemia, bypass run-off, and presence of infection, using stepwise logistic regression analysis. RESULTS: Ninety-three patients (55 male, 38 female; mean age 69) underwent 100 infrainguinal bypasses. Twenty-six high-grade graft stenoses (>70%) were identified in 26 patients during follow-up (mean 21 months) by graft-flow peak systolic velocity (PSV) >300 cm/sec on more than one duplex examination, and were electively revised. Graft flow disturbances (180 cm/sec >PSV <300 cm/sec) were identified in an additional 13 grafts (6 regressed, 7 observed). The need for graft revision was associated with an early graft flow disturbance (P = 0.02), or drop in ankle-brachial index >0.15 (P = 0.03), and the use of an alternative conduit in 13 of 100 grafts (P = 0.04). Only smoking was associated with the development of a duplex detected graft flow disturbance during follow up (P = 0.03). CONCLUSION: Grafts with early flow disturbances warrant close duplex surveillance to identify graft-threatening stenosis. Risk factors that may predict future lower extremity bypass graft stenosis are smoking and the use of alternative bypass conduits.

The thrombosed arteriovenous graft: an endovascular model for vascular surgeons.

Arteriovenous dialysis grafts are the most commonly implanted prosthetic grafts. Thrombectomy with selective graft revision is traditional therapy for occlusions, but patency is minimally prolonged. Stenoses are determined by tactile feedback from an embolectomy catheter and lack of prograde and retrograde bleeding. An objective method for studying the graft and inflow and outflow tracts that permits appropriate endoluminal or surgical correction is described. This approach is appealing because: (i) the current approach is inadequate; (ii) it offers an objective, quantitative method to determine frequency and severity of critical stenoses within the failed access graft; (iii) remote and perigraft stenoses can be treated at the same setting; and (iv) it promotes the development of endovascular skills by surgeons in a high-volume, low-risk setting.