warfarin and Graft-Occlusion--Vascular

Trapeziometacarpal osteoarthritis is associated with more pain and restrictions than other hand osteoarthritis due to the functional importance of the thumb. While the effectiveness of surgical and pharmacological interventions has been widely examined, there is a lack of specific evidence about conservative non-pharmacological trapeziometacarpal osteoarthritis therapies. The objective of this systematic review was to provide evidence-based knowledge on the effectiveness of physiotherapy and occupational therapy on pain, function and quality of life.. A literature search of Medline, CINAHL, PEDro, OTseeker, EMB Dare Cochrane Database of Systematic Reviews and Cochrane CENTRAL was performed. Randomized and quasi-randomized controlled trials and corresponding systematic reviews, observational studies, pragmatic studies and case-control studies were included. The risk of bias was assessed.. Physical and occupational therapy-related interventions, especially multimodal interventions, seem to be effective to treat pain in patients with trapeziometacarpal osteoarthritis. Pre-fabricated neoprene splints and custom-made thermoplastic splints may reduce pain equally. Single interventions seem not to be effective. Significant evidence for effectiveness on function and quality of life could not be found.. The sole Na. The SUV. Genetic variants of

Topics: AC133 Antigen; Acenaphthenes; Acer; Acrosome Reaction; Adult; Agaricales; Aged; Aged, 80 and over; Animals; Animals, Zoo; Anti-Bacterial Agents; Anticoagulants; Antifungal Agents; Antimanic Agents; Antioxidants; Aortic Valve; Area Under Curve; ATP Binding Cassette Transporter, Subfamily G, Member 2; Bacillus; Bacterial Toxins; Bacterial Typing Techniques; Base Composition; Beauveria; Binge Drinking; Biomarkers; Bipolar Disorder; Blood Coagulation; Blotting, Western; Brachytherapy; Calcium Channels, L-Type; Carcinoma, Non-Small-Cell Lung; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cell Transformation, Neoplastic; Cell Wall; Cells, Cultured; Ceramics; Chi-Square Distribution; China; Chlorophyll; Chlorophyta; Chloroplasts; Cholesterol, HDL; Chromatography, High Pressure Liquid; Chromobacterium; Clostridium perfringens; Clozapine; Constriction, Pathologic; Coronary Artery Bypass; Corticotropin-Releasing Hormone; Cross-Sectional Studies; Cytochrome P-450 CYP2C9; Dental Porcelain; Dental Restoration Failure; Dental Stress Analysis; Designer Drugs; Diaminopimelic Acid; DNA Fingerprinting; DNA, Bacterial; Dose-Response Relationship, Drug; Dose-Response Relationship, Radiation; Drug Dosage Calculations; Drug Evaluation, Preclinical; Drug Resistance, Bacterial; Elasticity Imaging Techniques; Epsilonproteobacteria; Equipment Design; Ericaceae; Excitatory Amino Acid Antagonists; False Negative Reactions; Fatty Acids; Female; Food Analysis; Fresh Water; Gene Expression Regulation, Neoplastic; Glutathione; Graft Occlusion, Vascular; Heart Valve Prosthesis Implantation; Heart Ventricles; HEK293 Cells; Hemolymph; Humans; Hyaluronan Receptors; Hydrogen Peroxide; Hydrothermal Vents; Indoles; Inflammation Mediators; Inhibitory Concentration 50; Insecta; International Normalized Ratio; Isotope Labeling; Itraconazole; Kidney; Kinetics; Kruppel-Like Factor 4; Kruppel-Like Transcription Factors; Lamotrigine; Lanthanoid Series Elements; Limit of Detection; Linear Models; Lipid Peroxidation; Liver; Liver Cirrhosis; Logistic Models; Lung Neoplasms; Lymph Node Excision; Lymphatic Metastasis; Male; Malondialdehyde; Mediastinum; Metronidazole; Mice; Mice, Nude; Mice, Transgenic; Microbial Sensitivity Tests; Microscopy, Fluorescence; Middle Aged; Monocytes; Monomeric GTP-Binding Proteins; Multivariate Analysis; Myocytes, Cardiac; Neoplasm Staging; Neoplastic Stem Cells; Neural Pathways; Nitrates; Nucleic Acid Hybridization; Octamer Transcription Factor-3; Odds Ratio; Oxidation-Reduction; Oxidative Stress; Peptidoglycan; Phantoms, Imaging; Pharmacogenetics; Pharmacogenomic Variants; Phenotype; Phospholipids; Photolysis; Photosynthesis; Phylogeny; Plant Extracts; Polychaeta; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Preoperative Care; Prostatic Neoplasms; Pseudomonas aeruginosa; Pyrimidines; Pyrroles; Quorum Sensing; Radiology, Interventional; Radiopharmaceuticals; Radiotherapy Dosage; Rats; Rats, Sprague-Dawley; Receptors, Corticotropin-Releasing Hormone; Reference Values; Regression Analysis; Retrospective Studies; Reverse Transcriptase Polymerase Chain Reaction; Rhizosphere; Risk Factors; RNA, Ribosomal, 16S; ROC Curve; Rutin; Saphenous Vein; Seawater; Selenium; Semen Preservation; Sensitivity and Specificity; Septal Nuclei; Sequence Analysis, DNA; Serum Albumin; Serum Albumin, Human; Shear Strength; Sodium Pertechnetate Tc 99m; Sodium-Hydrogen Exchangers; Soil Microbiology; SOXB1 Transcription Factors; Spain; Species Specificity; Sperm Motility; Spermatozoa; Spheroids, Cellular; Spores, Fungal; Stroke; Superoxide Dismutase; Swine; Tandem Mass Spectrometry; Technetium Compounds; Technetium Tc 99m Exametazime; Technetium Tc 99m Sestamibi; Temperature; Thiosulfates; Thrombosis; Thyroid Neoplasms; Transducers; Transfection; Transplantation, Heterologous; Treatment Outcome; Triazines; Tumor Burden; Urocortins; Uterine Cervical Neoplasms; Vacuoles; Valproic Acid; Ventral Tegmental Area; Vitamin K 2; Vitamin K Epoxide Reductases; Warfarin; Water Microbiology; Young Adult

Early clinical trials of eptifibatide did not show a significant association between eptifibatide and the development of thrombocytopenia, thrombosis, or disseminated intravascular coagulation. However, more recent literature has suggested a significant association between eptifibatide and the development of thrombocytopenia and thrombosis. Although the true incidence and the pathophysiology of these associations are unknown, the development of these events can be life-threatening. Herein, we describe the case of a patient who experienced acute onset of profound thrombocytopenia, developing thrombosis, pulmonary emboli, and disseminated intravascular coagulation. This paper adds to the few previous reports of cases that suggested an association between thrombocytopenia, thrombosis, and the administration of eptifibatide. To the best of our knowledge, this is the first case report in the medical literature that associates the new onset of thrombocytopenia, thrombosis, and disseminated intravascular coagulation with the administration of eptifibatide. We also provide a subject review.

Topics: Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Blood Coagulation Tests; Coronary Artery Bypass; Disseminated Intravascular Coagulation; Drug Substitution; Drug-Eluting Stents; Eptifibatide; Graft Occlusion, Vascular; Humans; Male; Peptides; Platelet Aggregation Inhibitors; Platelet Count; Predictive Value of Tests; Pulmonary Embolism; Severity of Illness Index; Thrombocytopenia; Thrombosis; Time Factors; Treatment Outcome; Warfarin

The recently described complication of late and very late stent thrombosis with coronary stents has raised the question of when is it safe to stop antiplatelet therapy in the era of drug eluting stents? With several million patients having already had coronary stents implanted worldwide, the importance of an appreciation of stent thrombosis is not only critical to the cardiologist but also surgeon, physician, dentist and other specialists that perform procedures on patients which require with-holding antiplatelet agents. Currently there is great concern amongst medical professionals on how to manage this group of patients in the absence of clear guidelines. This article reviews the current data on coronary stents, in-stent restenosis and stent thrombosis and role of antiplatelet medication post percutaneous coronary intervention (PCI) to provide a concise and clear algorithm for managing perioperative antiplatelet therapy in patients having undergone recent PCI. The algorithm encourages a multidisciplinary approach and is based on the surgical bleeding risk, operative risk of adverse cardiac events and stent thrombosis risk to guide safe practice. Challenging areas including aspirin and clopidogrel hypersensitivity, clopidogrel resistance and concomitant vitamin K antagonist therapy are also addressed.

Topics: Coronary Thrombosis; Drug Hypersensitivity; Drug Resistance; Drug Therapy, Combination; Drug-Eluting Stents; Graft Occlusion, Vascular; Humans; Platelet Aggregation Inhibitors; Warfarin

Topics: Angioplasty, Balloon, Coronary; Arterial Occlusive Diseases; Aspirin; Clopidogrel; Endarterectomy, Carotid; Fibrinolytic Agents; Graft Occlusion, Vascular; Humans; Leg; Peripheral Vascular Diseases; Platelet Aggregation Inhibitors; Thromboembolism; Ticlopidine; Warfarin

To evaluate the role of antithrombotic therapy, on preserving graft patency, we performed a meta-analysis of randomized clinical trials involving aspirin (ASA), dipyridamole (D), anticoagulants (AC) and placebo or nontreatment controls (P). Manual literature searches were performed supplemented by computerized MEDLINE listings complete to July 1991. Saphenous vein graft occlusion was determined by angiography (patients with > or = 1 distal anastomotic occlusion). The trial data were aggregated with the methods of Mantel and Haenszel. The results are reported as odds ratios (OR) +/- 95% confidence intervals (CI). Seventeen trials were evaluated. Aspirin strongly influenced graft occlusion [ASA +/- D vs P: OR 0.60, 95% CI 0.51, 0.71, P < 0.0001], but dipyridamole provided no additional benefit [ASA+D vs ASA: OR 0.94, 95% CI 0.72, 1.24, P = 0.71]. Anticoagulants reduced graft occlusion [AC vs P: OR 0.56, 95% CI 0.33, 0.93, P = 0.025] and the results were similar to that achieved with aspirin [ASA vs AC: OR 0.95, 95% CI 0.62, 1.44, P = 0.87]. The combination of aspirin and anticoagulants was superior to anticoagulants alone in two limited trials [ASA+AC vs AC: OR 0.55, 95% CI 0.33, 0.88, P = 0.01]. A low (100 mg) to medium (325 mg) daily aspirin dosage was more effective than a high dose (975 mg). Early postoperative treatment (< or = 6 h) strongly influenced graft occlusion while preoperative administration provided no additional benefit. No mortality advantage was identified for any antithrombotic therapy. Aspirin or anticoagulants enhance saphenous vein graft patency following aortocoronary bypass surgery, and a combination thereof deserves further investigation in a trial large enough to detect the effects of these treatments with respect to clinical events.

Topics: Anticoagulants; Aspirin; Coronary Artery Bypass; Dipyridamole; Drug Therapy, Combination; Graft Occlusion, Vascular; Logistic Models; Postoperative Complications; Randomized Controlled Trials as Topic; Risk; Treatment Outcome; Warfarin

Patients having undergone femoropopliteal bypass surgery remain at significant risk of graft failure. Although antithrombotic therapy is of paramount importance in these patients, the effect of oral anticoagulation therapy (OAT) on outcomes remains unresolved. We performed a randomized, prospective study to assess the impact of OAT plus clopidogrel vs dual antiplatelet therapy on peripheral vascular and systemic cardiovascular outcomes in patients who had undergone femoropopliteal bypass surgery.. Three hundred forty-one patients who had undergone femoropopliteal surgery were enrolled and randomized: 173 patients received clopidogrel 75 mg/d plus OAT with warfarin (C + OAT), and 168 patients received dual antiplatelet therapy with clopidogrel 75 mg/d plus aspirin 100 mg/d (C + acetylsalicylic acid [ASA]). Study end points were graft patency and the occurrence of severe peripheral arterial ischemia, and the incidence of bleeding episodes.. Follow-up ranged from 4 to 9 years. The graft patency rate and the freedom from severe peripheral arterial ischemia was significantly higher in C + OAT group than in C + ASA group (P = .026 and .044, respectively, Cox-Mantel test). The linearized incidence of minor bleeding complications was significantly higher in C + OAT group than in C + ASA group (2.85% patient-years vs 1.37% patient-years; P = .03). The incidence of major adverse cardiovascular events, including mortality, was found to be similar (P = .34) for both study groups.. In patients who have undergone femoropopliteal vascular surgery, combination therapy with clopidogrel plus warfarin is more effective than dual antiplatelet therapy in increasing graft patency and in reducing severe peripheral ischemia. These improvements are obtained at the expenses of an increase in the rate of minor anticoagulation-related complications.

Topics: Administration, Oral; Aged; Aspirin; Cardiovascular Diseases; Chi-Square Distribution; Clopidogrel; Comorbidity; Drug Therapy, Combination; Female; Femoral Artery; Graft Occlusion, Vascular; Humans; Logistic Models; Male; Peripheral Vascular Diseases; Platelet Aggregation Inhibitors; Popliteal Artery; Proportional Hazards Models; Prospective Studies; Ticlopidine; Treatment Outcome; Vascular Patency; Warfarin

Although moderate drinking has been associated with lower mortality among patients after myocardial infarction, its relationship with prognosis and graft obstruction among patients with coronary artery bypass grafts is unknown.. We studied 1351 patients enrolled in the Post-CABG trial, who had undergone coronary bypass surgery 1 to 11 years before entry. Participants were randomly assigned to lovastatin in low or high doses and to low-dose warfarin or placebo in a factorial design. Participants underwent coronary angiography at baseline and after a mean follow-up of 4.3 years and were followed up for a composite end point of death, myocardial infarction, stroke, bypass surgery, or angioplasty. We categorized reported weekly alcohol intake as abstention (<1 drink), light (1-6 drinks), moderate (7-13 drinks), and heavier (> or =14 drinks).. During follow-up, 238 participants sustained a clinical event. Moderate drinking was associated with a trend toward both fewer clinical events (hazard ratio 0.7, 95% CI 0.4-1.1) and less angiographic progression (odds ratio 0.7, 95% CI 0.5-1.1), although neither of these effects were statistically significant. High-density lipoprotein cholesterol appeared to account for one third of the trend toward lower risk among moderate drinkers.. We did not demonstrate statistically significant differences in prognosis according to alcohol intake in this study, although there were inverse trends between moderate drinking and both morbidity and graft progression of a magnitude similar to studies in other populations. Larger studies of alcohol intake among patients with coronary artery bypass grafts are needed.

Topics: Alcohol Drinking; Anticholesteremic Agents; Anticoagulants; Cholesterol, HDL; Coronary Angiography; Coronary Artery Bypass; Coronary Disease; Disease Progression; Female; Graft Occlusion, Vascular; Humans; Lovastatin; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Prognosis; Prospective Studies; Risk Factors; Sensitivity and Specificity; Smoking; Warfarin

Poor patency of synthetic grafts for infragenicular revascularization has led to use of distal vein patches or cuffs. The aim of this study was to compare the distally widened Distaflo PTFE graft, which mimics a vein cuff, with a PTFE graft with distal vein modification. In this prospective, randomized, multicenter trial we compared use of a precuffed PTFE graft wit that of PTFE grafts with distal vein modification for infragenicular revascularization in patients with critical limb ischemia without saphenous vein. Study end points were primary and secondary patency and limb salvage rates at 2 years. From January 28,1999 to November 1, 2000, 104 patients were enrolled in 10 North American centers. Thirteen were excluded for protocol violation. Ninety-one bypasses were performed in 89 patients with a mean age of 73 years (range 47-90). By randomization, 47 bypasses were done with the precuffed graft and 44 with PTFE graft with vein cuff. Both groups were comparable for comorbidities and operative variables, except for a higher incidence of acute ischemia in the precuffed group (19% vs. 4.5%, p = 0.03). Bypass was a redo procedure in 53% and was performed at the infrapopliteal vessels in 79%. Operative mortality was 2.2% (2/91). Mean follow-up was 14 months (range 1-30). At 1 and 2 years, primary patency was 52% and 49% for the precuffed group and 62% and 44% for the vein cuffed group, respectively (p = 0.53). At 1 year and 2 years, the limb salvage rate was 72% and 65% for the precuffed group and 75% and 62% in the vein cuffed group (p = 0.88). Although numbers are small and follow-up short, this midterm analysis shows similar results for the Distaflo precuffed grafts and PTFE grafts with vein cuff. A precuffed graft is a reasonable alternative conduit for infragenicular reconstruction in the absence of saphenous vein and provides favorable limb salvage.

Topics: Aged; Aged, 80 and over; Anastomosis, Surgical; Anticoagulants; Arterial Occlusive Diseases; Aspirin; Blood Vessel Prosthesis; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Iliac Artery; Ischemia; Limb Salvage; Lower Extremity; Male; Middle Aged; Platelet Aggregation Inhibitors; Polytetrafluoroethylene; Popliteal Artery; Prospective Studies; Prosthesis Design; Reoperation; Tibial Arteries; Time Factors; Treatment Outcome; Vascular Patency; Warfarin

Polytetrafluoroethylene (PTFE) dialysis grafts in patients with end-stage renal disease (ESRD) are prone to thrombotic failure. The objective of this multicenter, randomized, double-blind, placebo-controlled clinical trial was to determine if warfarin reduces the risk of failure of PTFE dialysis grafts. Patients with ESRD and newly placed PTFE grafts were studied at community and academic dialysis centers in Southwestern Ontario. Patients were allocated to receive warfarin or matching placebo, with the warfarin administered to achieve a target INR of 1.4 to 1.9. Time to graft failure was the main outcome measure. A total of 107 patients (56 allocated to warfarin) were randomized. The time-to-event analysis revealed no significant difference in the likelihood of graft survival between the two groups (odds ratio, 1.76 in favor of placebo; 95% confidence interval, 0.72 to 4.34). Six major bleeds occurred in five patients allocated to warfarin compared with none in the patients who received placebo (P = 0.03). In conclusion, low-dose warfarin was associated with an excess of clinically important major bleeding in patients with ESRD enrolled in this study. Furthermore, low-intensity, monitored-dose warfarin does not appear to prolong PTFE graft survival.

Topics: Adult; Aged; Aged, 80 and over; Anticoagulants; Blood Vessel Prosthesis; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Kidney Failure, Chronic; Male; Middle Aged; Polytetrafluoroethylene; Renal Dialysis; Thrombosis; Treatment Outcome; Warfarin

A recent retrospective study showed that the ischemic consequences of femoropopliteal bypass graft occlusion were more severe with polytetrafluoroethylene (PTFE) than with vein. This study examines this conclusion and whether oral anticoagulation therapy reduces the degree of ischemia after occlusion of PTFE and vein femoropopliteal bypass grafts.. Four hundred two patients who underwent femoropopliteal bypass grafting (233 PTFE and 169 vein) were randomized to a postoperative regimen of either warfarin (international normalized ratio, 1.4 to 2.8) and aspirin (WASA; 325 mg daily) therapy or aspirin alone (ASA) therapy. The grade of acute ischemia at the time of graft occlusion was assessed with the Society of Vascular Surgery recommended reporting standards (I, viable; II, threatened). Early graft occlusions (<30 days) were excluded.. There were 100 graft occlusions (67 PTFE and 33 vein) during a mean follow-up period of 36 months (PTFE) and 39 months (vein). Forty-eight patients were randomized to WASA therapy, and 52 were randomized to ASA therapy. The patients were well matched for age, atherosclerotic risk factors, operative indication, and preoperative ankle-brachial index. Overall, a greater percentage of the PTFE occlusions caused grade II ischemia than did the vein graft occlusions (48% versus 18%; P =.005). The ankle-brachial index at the time of graft occlusion was significantly lower in the PTFE grafts than in the vein grafts (0.28 versus 0.45; P =.001). The patients with PTFE who were undergoing WASA therapy at the time of graft occlusion had less grade II ischemia than did those patients who were undergoing ASA therapy (28% versus 55%; P =.057). However, the incidence rate of severe ischemia after graft occlusion remained greater with PTFE grafts and WASA therapy as compared with all the vein grafts (28% versus 18%). The vein graft occlusions had the same incidence rate of grade II ischemia with WASA therapy as with ASA therapy (20% versus 17%; P = 1.0).. The ischemic consequences of femoropopliteal bypass graft occlusion are worse with PTFE than with vein. Treatment with WASA therapy lessens the severity of acute ischemia after the occlusion of PTFE graft as compared with ASA therapy but not to the degree seen with vein graft occlusion. Occlusion of femoropopliteal vein grafts is seldom accompanied by severe ischemia and is not improved with WASA therapy.

Topics: Aged; Amputation, Surgical; Anticoagulants; Aspirin; Boston; Femoral Vein; Fibrinolytic Agents; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Incidence; Intermittent Claudication; International Normalized Ratio; Ischemia; Leg; Maryland; Middle Aged; Polytetrafluoroethylene; Popliteal Vein; Prospective Studies; Severity of Illness Index; Texas; Treatment Outcome; Warfarin

Since coronary artery bypass graft patients remain at risk of coronary artery and bypass graft occlusion after successful surgery, adjunct treatment regimens are under investigation. In a study of the patients of the multicenter Post Coronary Artery Bypass Graft (Post CABG) Trial, 1 mg warfarin was found to have no important effect on coagulation parameters.. The effects of 1, 2 and 3 mg warfarin were evaluated at six-week intervals in 20 Post CABG Trial patients receiving titrated dose increases in comparison to 20 patients of similar age, gender and time from CABG treated with placebo.. International normalized ratio (INR) values increased with warfarin dose increments for 1, 2, and 3 mg, respectively (0.95+/-0.16, 1.08+/-0.19, and 1.34+/-0.39) and in comparison to placebo treated patients (dosextreatment p<0.001). Factor VII coagulant activity decreased with warfarin titration (1 mg, 119.0+/-18.3 %; 2 mg, 100.6+/-32.8 %; 3 mg, 95.0+/-27.8 %) and in comparison to placebo (dosextreatment p=0.008). Levels of prothrombin fragment F1.2, tissue plasminogen activator, fibrinogen and von Willebrand factor were unchanged with warfarin dose increments and in comparison to placebo.. At doses up to 3 mg, warfarin acts on the INR through a reduction of factor VII with no effect on the fibrinolytic system, fibrinogen or von Willebrand factor. At these doses F1.2 did not document reduced coagulation activity. The observations of this study were consistent with the decision in the Post CABG Trial to increase the warfarin dose above 1 mg to achieve a distinct effect of warfarin that was less than full anticoagulation.

Topics: Adult; Aged; Anticoagulants; Aspirin; Coronary Artery Bypass; Coronary Disease; Dose-Response Relationship, Drug; Drug Therapy, Combination; Factor VII; Female; Fibrinogen; Graft Occlusion, Vascular; Humans; International Normalized Ratio; Male; Middle Aged; Peptide Fragments; Postoperative Complications; Postoperative Hemorrhage; Prothrombin; Recurrence; Saphenous Vein; Thrombosis; Tissue Plasminogen Activator; Treatment Outcome; von Willebrand Factor; Warfarin

Obstructive changes often occur in aortocoronary saphenous-vein bypass grafts because of atherosclerosis and thrombosis. We studied whether aggressive lowering of low-density lipoprotein (LDL) cholesterol levels or low-dose anticoagulation would delay the progression of atherosclerosis in grafts.. We studied 1351 patients who had undergone bypass surgery 1 to 11 years before base line and who had an LDL cholesterol level between 130 and 175 mg per deciliter and at least one patent vein graft as seen on angiography. We used a two-by-two factorial design to assign patients to aggressive or moderate treatment to lower LDL cholesterol levels (with lovastatin and, if needed, cholestyramine) and to treatment with warfarin or placebo. Angiography was repeated an average of 4.3 years after base line. The primary angiographic outcome was the mean percentage per patient of grafts with a decrease of 0.6 mm or more in lumen diameter.. As measured annually during the study period, the mean LDL cholesterol level of patients aggressive treatment ranged from 93 to 97 mg per deciliter; with moderate treatment, the range was from 132 to 136 mg per deciliter (P<0.001). The mean international normalized ratio was 1.4 in the warfarin group and 1.1 in the placebo group (P<0.001). The mean percentage of grafts with progression of atherosclerosis was 27 percent for patients whose LDL cholesterol level was lowered with aggressive treatment, and 39 percent for those who received moderate treatment (P<0.001). There was no significant difference in angiographic outcome between the warfarin and placebo groups. The rate of revascularization over four years was 29 percent lower in the group whose LDL cholesterol level was lowered aggressively than in the group receiving moderate treatment (6.5 percent vs. 9.2 percent, P= 0.03).. Aggressive lowering of LDL cholesterol levels to below 100 mg per deciliter reduced the progression of atherosclerosis in grafts. Low-dose warfarin did not reduce the progression of atherosclerosis.

Topics: Adult; Aged; Anticholesteremic Agents; Anticoagulants; Cholesterol, LDL; Cholestyramine Resin; Coronary Angiography; Coronary Artery Bypass; Coronary Artery Disease; Coronary Thrombosis; Drug Therapy, Combination; Female; Graft Occlusion, Vascular; Humans; Hypercholesterolemia; Life Tables; Lovastatin; Male; Middle Aged; Saphenous Vein; Treatment Outcome; Warfarin

We analyzed a current 78-month experience with externally supported (ringed) polytetrafluoroethylene (PTFE) axillobifemoral (AxBF) and axillounifemoral (AxUF) bypass grafts to address the controversy about whether the addition of a femorofemoral limb to an axillofemoral bypass graft improves the patency results.. Between January 1988 and June 1994, 36 AxBF and 22 AxUF externally supported PTFE ringed bypass grafts were performed at our institution. The age of the patients in the AxBF group was 67 +/- 11 years and 69 +/- 11 years in the AxUF group. The male/female ratio was 22:13 (AxBF) and 8:9 (AxUF). In 71% of cases (29/36 AxBF, 12/22 AxUF), the operations were performed for aortoiliac atherosclerotic occlusive disease in patients with significant medical risk factors or a "hostile" abdomen. The remaining 29% were patients requiring revascularization during treatment of an infected aortic graft. Bypass patency was assessed in the follow-up period by clinical evaluation, color-flow duplex imaging, or segmental limb pressure measurements.. There was no significant difference in the 30-day operative mortality rate for all AxBF bypasses (11%) and all AxUF bypasses (6%) (p = 0.89 by chi-squared testing). The primary and secondary patency rates for the whole group of bypasses were 80% and 89% at 3 years, respectively (SE < 0.1). Between the AxBF and AxUF groups, there were no significant differences in either primary patency (80% for each group) or secondary patency (91% in AxBFs vs 85% in AxUFs) (SE < 0.1) at 2 years (Wilcoxon rank sum test).. These data show no differences in the patency of externally supported PTFE AxBF and AxUF bypass grafts up to 2 years after implantation.

Topics: Aged; Aged, 80 and over; Anastomosis, Surgical; Aorta; Arteriosclerosis; Aspirin; Axillary Artery; Blood Vessel Prosthesis; Combined Modality Therapy; Female; Femoral Artery; Follow-Up Studies; Graft Occlusion, Vascular; Graft Survival; Humans; Male; Middle Aged; Polytetrafluoroethylene; Prosthesis Design; Reoperation; Thrombectomy; Thrombosis; Time Factors; Vascular Patency; Warfarin

We analyzed the short- and long-term results for patients undergoing thrombolysis of occluded infrainguinal bypass grafts at our institution over a 62-month period.. Thirty-one patients with 40 episodes of graft thrombosis in 33 grafts managed by thrombolysis were retrospectively reviewed. The effects of graft age, material, and anatomy, symptoms, treatment, anticoagulation, and occlusion duration were evaluated for impact on patency after thrombolysis. Dose and duration of therapy with use of the technique of pulse-spray thrombolysis was assessed.. Thrombolysis successfully reestablished patency in 92% of grafts treated. Mean lysis time and urokinase dose were 118 minutes and 607,000 units, respectively. Responsible lesions were identified and treated by angioplasty or surgery in 35 of 37 cases. The patency rate after thrombolysis was 28% at 30 months, and the secondary patency rate was 46% at 18 months. Duration of occlusion, symptoms, treatment, graft anatomy, and prior graft revision did not impact on patency. Mean secondary patency was 21.5 months in grafts in place over 1 year and 7.0 months in grafts in place for less than 1 year. Mean secondary patency was 23.8 months in polytetrafluoroethylene grafts and 8.4 months in vein grafts. The limb salvage rate was 84% at 30 months, and the patient survival rate was 84% at 42 months.. Pulse-spray thrombolysis is effective in rapidly recanalizing thrombosed infrainguinal grafts. Grafts failing in the first year after placement should generally be replaced, reserving thrombolysis and revision for grafts greater than 1 year old. Vein grafts tolerate thrombosis less well than synthetic conduits and have decreased long-term patency.

Topics: Adult; Aged; Angioplasty; Arteriovenous Shunt, Surgical; Combined Modality Therapy; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Intermittent Claudication; Ischemia; Leg; Life Tables; Male; Middle Aged; Polytetrafluoroethylene; Popliteal Vein; Prosthesis Failure; Recombinant Proteins; Reoperation; Retrospective Studies; Survival Rate; Thrombolytic Therapy; Tibial Arteries; Time Factors; Tissue Plasminogen Activator; Urokinase-Type Plasminogen Activator; Vascular Patency; Warfarin

Oral anticoagulant therapy with warfarin commenced pre-operatively (n = 102) to prevent coronary artery vein graft occlusions was compared in terms of efficacy and safety with dipyridamole and aspirin (n = 130) in a randomized consecutive series of patients. Anticoagulant therapy was started at least 2 weeks before coronary artery bypass surgery (CABG) and antiplatelet therapy was started at least 3 days before CABG with dipyridamole followed by a combination of 250 mg aspirin once a day via a nasogastric tube 6 h after CABG. Overall, vein graft patency at 3 months after surgery did not differ significantly between the anticoagulant group (203/275, 74%) and dipyridamole-aspirin group (238/311, 77%), but the occlusion rate for grafts with endarterectomy was higher in the anticoagulant (46%) than in the dipyridamole and aspirin group (16%), (P less than 0.05). The rate of peri-operative complications including deaths, re-operation and myocardial infarction was higher in the anticoagulant than antiplatelet group (26.5% vs 13.8%, P less than 0.05). The occurrence of postoperative bleeding complications did not differ significantly between the groups. Thus, oral anticoagulant therapy commenced pre-operatively has no advantages over conventional antiplatelet therapy in patients who undergo CABG. Neither antithrombotic regimens proved to be satisfactory for preventing acute bypass vein graft occlusions in this patient population with advanced coronary artery disease.

Topics: Aspirin; Cardiac Catheterization; Coronary Artery Bypass; Coronary Disease; Dipyridamole; Drug Therapy, Combination; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Premedication; Reoperation; Warfarin

A prospective randomized study was performed in 137 coronary artery bypass surgery cases to determine if the administration of antiplatelet drugs would improve the patency of coronary artery bypass grafts. The warfarin group received warfarin and thrombotest was controlled to 20% or so. The dipyridamole group received both 300 mg of dipyridamole and 250 mg of aspirin orally each day. These two groups were compared for study in grafts patency. Results were analyzed by chi-square. In the warfarin group, 66 patients had three ITA-LAD grafts and 115 saphenous vein grafts (including 4 sequential grafts). In the dipyridamole group, 71 patients underwent 38 ITA grafts and 167 saphenous vein grafts (including 56 sequential grafts). Eighty-eight of the 107 grafts (82%) were patent in the warfarin group, and 190 of 205 grafts (95%) were patent in the dipyridamole group (p less than 0.01). Of the two ITA grafts in the warfarin group, no graft was occluded, a patency of 100%. In the dipyridamole group, 35 of 38 ITA grafts (92%) were patent. In the warfarin group, 86 of 105 saphenous vein grafts (82%) were patent. In the dipyridamole group, 155 of 167 saphenous vein grafts (95%) were patent (p less than 0.01). In the study of grafted coronary vessel, the patency of left anterior descending coronary artery, diagonal branch and right coronary artery was not significant between two groups. In the dipyridamole group, the patency of left circumflex coronary artery was 93%, and that of the warfarin group was 50% (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Anticoagulants; Chi-Square Distribution; Coronary Artery Bypass; Dipyridamole; Female; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Postoperative Care; Prospective Studies; Random Allocation; Saphenous Vein; Vascular Patency; Warfarin

Saphenous vein graft (SVG) is the most commonly used conduits in coronary artery bypass grafting (CABG), but the disadvantage of SVG is its tendency for progressive failure. We hypothesized that therapeutic-dose warfarin (international normalized ratio [INR] >1.6) plus aspirin improve SVG patency. This study aimed to evaluate the factors contributing to SVG patency.. Since 2010-2020, 199 patients who underwent isolated CABG using SVG were divided into two groups according to their INR values in the first year: group T (INR >1.6) and group L (INR <1.6).. Group T had 162 SVGs (105 patients) and group L had 151 SVGs (94 patients). The 1-, 4-, and 7-year SVG patency rates were higher in group T than in group L (99%, 96%, and 92% vs. 93%, 86%, and 79%, respectively; p = 0.00378). The 1-, 4-, and 7-year freedom from repeat-revascularization was higher in group T than in group L (100%, 100%, and 99% vs. 98%, 95%, and 87%, respectively; p = 0.0264). Multivariate analysis showed that therapeutic-dose warfarin (p = 0.00204) and target vessel diameter (p <0.0001) were independent risk factors of SVG occlusion.. Therapeutic-dose warfarin (INR >1.6) plus aspirin after CABG improved the long-term patency of SVG and decreased repeat-revascularization rate.

Topics: Aspirin; Coronary Angiography; Graft Occlusion, Vascular; Humans; International Normalized Ratio; Saphenous Vein; Treatment Outcome; Vascular Patency; Warfarin

Extracranial carotid artery aneurysms (ECAA) are extremely rare, accounting for less than 1% of all peripheral artery aneurysms. The most common presentation is central neurologic dysfunction, typically due to embolization of thrombus from the aneurysm. Historically open surgical intervention is the treatment of choice for symptomatic ECAA. Recent data suggest that endovascular repair is a valuable alternative, with a high procedural success rate and relatively low complication rate. We present a case of an ECAA with symptoms of vision loss, successfully treated by endovascular covered stenting but complicated by late in stent thrombosis and cerebral infarction. The patient was subsequently treated with IV thrombolysis and life-long warfarin. The patient had discrete residual symptoms at follow-up 3 months later.

Topics: Aneurysm; Anticoagulants; Carotid Artery Diseases; Endovascular Procedures; Female; Graft Occlusion, Vascular; Humans; Middle Aged; Stents; Thrombolytic Therapy; Thrombosis; Warfarin

Essentials Uncertainty remains about antiplatelets for vascular access patency in hemodialysis patients. 95 971 people under hemodialysis were followed in a claims database in Taiwan. Aspirin reduced vascular access failure rate and did not increase major bleeding rate. Clopidogrel, Aggrenox, and warfarin might increase major bleeding rate. SUMMARY: Background Dialysis adequacy is a major determinant of survival for patients with end-stage renal disease. Good vascular access is essential to achieve adequate dialysis. Objectives This study evaluated the impacts of different drugs on the vascular access failure rate of an arteriovenous fistula or an arteriovenous graft and the rate of major bleeding in hemodialysis patients. Patients and methods We studied patients with end-stage renal disease registered in the Taiwan National Health Insurance program from 1 January 1997 to 31 December 2012. A total of 95 971 patients were enrolled in our study. Vascular access dysfunction was defined as the need for thrombectomy or percutaneous angioplasty. Major bleeding was defined as emergency department visits or hospitalization with a primary diagnosis of gastrointestinal bleeding or intracerebral hemorrhage. The adjusted odds ratios between person-quarters with or without antiplatelet or oral anticoagulant use were calculated using a generalized estimating equation. Results The odds ratio of vascular access failure was 0.21 (0.11-0.39) for aspirin, 0.76 (0.74-0.79) for clopidogrel, 0.67 (0.59-0.77) for dipyridamole, 0.67 (0.53-0.86) for Aggrenox and 0.96 (0.90-1.03) for warfarin. The highest odds ratio for intracerebral hemorrhage was 5.33 (1.25-22.72) in younger patients using Aggrenox. The highest odds ratio for gastrointestinal bleeding was 1.34 (1.10-1.64) for clopidogrel. Conclusion Antiplatelet agents, but not warfarin, might reduce the vascular access thrombosis rate. The gastrointestinal bleeding rate was increased in the group using clopidogrel. Aggrenox should be used with caution in young individuals because it might increase the rate of intracerebral hemorrhage.

Topics: Adult; Aged; Aged, 80 and over; Anticoagulants; Arteriovenous Shunt, Surgical; Aspirin; Aspirin, Dipyridamole Drug Combination; Blood Vessel Prosthesis Implantation; Clopidogrel; Databases, Factual; Female; Gastrointestinal Hemorrhage; Graft Occlusion, Vascular; Humans; Intracranial Hemorrhages; Kidney Failure, Chronic; Male; Middle Aged; Platelet Aggregation Inhibitors; Protective Factors; Renal Dialysis; Retrospective Studies; Risk Assessment; Risk Factors; Taiwan; Thrombosis; Treatment Failure; Warfarin; Young Adult

Topics: Adult; Anticoagulants; Combined Modality Therapy; Female; Graft Occlusion, Vascular; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Humans; Mitral Valve Insufficiency; Prosthesis Failure; Prosthesis-Related Infections; Reoperation; Staphylococcal Infections; Tricuspid Valve; Warfarin

Topics: Anticoagulants; Aortic Valve; Coronary Artery Bypass; Graft Occlusion, Vascular; Heart Valve Prosthesis Implantation; Humans; Male; Mammary Arteries; Middle Aged; Warfarin

Topics: Adult; Anticoagulants; Budd-Chiari Syndrome; Catheterization; Female; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Portal Vein; Portasystemic Shunt, Transjugular Intrahepatic; Stents; Tomography, X-Ray Computed; Ultrasonography, Interventional; Vascular Patency; Vena Cava, Inferior; Warfarin

Topics: Aspirin; Child, Preschool; Drug Substitution; Drug Therapy, Combination; Fibrinolytic Agents; Fontan Procedure; Graft Occlusion, Vascular; Heart Defects, Congenital; Heart Ventricles; Hemodynamics; Humans; Male; Pleural Effusion; Thrombosis; Time Factors; Treatment Outcome; Vascular Patency; Warfarin

Controversy regarding the efficacy of duplex ultrasound surveillance after infrainguinal vein bypass led to an analysis of patient and bypass graft characteristics predictive for development of graft stenosis and a decision of secondary intervention.. Retrospective analysis of a contemporary, consecutive series of 353 clinically successful infrainguinal vein bypasses performed in 329 patients for critical (n = 284; 80%) or noncritical (n = 69; 20%) limb ischemia enrolled in a surveillance program to identify and repair duplex-detected graft stenosis. Variables correlated with graft stenosis and bypass repair included: procedure indication, conduit type (saphenous vs nonsaphenous vein; reversed vs nonreversed orientation), prior bypass graft failure, postoperative ankle-brachial index (ABI) < 0.85, and interpretation of the first duplex surveillance study as "normal" or "abnormal" based on peak systolic velocity (PSV) and velocity ratio (Vr) criteria.. Overall, 126 (36%) of the 353 infrainguinal bypasses had 174 secondary interventions (endovascular, 100; surgery, 74) based on duplex surveillance; resulting in 3-year Kaplan-Meier primary (46%), assisted-primary (80%), and secondary (81%) patency rates. Characteristics predictive of duplex-detected stenosis leading to intervention (PSV: 443 +/- 94 cm/s; Vr: 8.6 +/- 9) were: "abnormal" initial duplex testing indicating moderate (PSV: 180-300 cm/s, Vr: 2-3.5) stenosis (P < .0001), non-single segment saphenous vein conduit (P < .01), warfarin drug therapy (P < .01), and redo bypass grafting (P < .001). Procedure indication, postoperative ABI level, statin drug therapy, and vein conduit orientation were not predictive of graft revision. The natural history of 141 (40%) bypasses with an abnormal first duplex scan differed from "normal" grafts by more frequent (51% vs 24%, P < .001) and earlier (7 months vs 11 months) graft revision for severe stenosis and a lower 3-year assisted primary patency (68% vs 87%; P < .001). In 52 (15%) limbs, the bypass graft failed and 20 (6%) limbs required amputation.. The efficacy of duplex surveillance after infrainguinal vein bypass may be enhanced by modifying testing protocols, eg, rigorous surveillance for "higher risk" bypasses, based on the initial duplex scan results and other characteristics (warfarin therapy, non- single segment saphenous vein conduit, redo bypass) predictive for stenosis development.

Topics: Anticoagulants; Extremities; Female; Graft Occlusion, Vascular; Humans; Ischemia; Male; Postoperative Care; Reoperation; Retrospective Studies; Risk Factors; Saphenous Vein; Time Factors; Treatment Failure; Ultrasonography, Doppler, Duplex; Vascular Patency; Vascular Surgical Procedures; Warfarin

We sought to describe modes of failure and associated limb loss after infrainguinal polytetrafluoroethylene bypass grafting in patients lacking a saphenous venous conduit and to define specific clinical or hemodynamic factors prognostic for bypass failure.. We identified 121 patients (mean age, 67 years; 90 men and 31 women) with determinable outcomes (minimum follow-up, 2 months; mean, 17 months) after 130 prosthetic infrainguinal bypasses between 1997 and 2005. Ischemic presentation was rest pain in 52%, tissue loss in 34%, and disabling claudication and/or popliteal aneurysm in 14%, with 24% of patients requiring a redo bypass. Distal targets were the above-knee (n = 44), distal popliteal (n = 27), or tibial/pedal (n = 59) arteries. Sixty-six (77%) of the below-knee (BK) target (distal popliteal or tibial) bypasses had distal anastomotic adjuncts (vein cuff or patch). Duplex graft surveillance was performed at 1, 4, and 7 months after surgery and twice yearly thereafter, with recording of midgraft velocities and imaging encompassing inflow and outflow vessels. Arteriography and open/endovascular intervention was performed for stenoses identified by duplex scanning (peak systolic velocity >300 cm/s; velocity ratio >3.5). An attempt was made to salvage occluded grafts by using catheter-directed thrombolysis or open techniques. Eighty-six patients (74% of BK bypasses) were placed on chronic warfarin therapy with a target international normalized ratio range between 2 and 3. Prognostic factors were identified by using univariate statistics and multivariate logistic regression analysis.. Three-year primary, assisted, and secondary patency rates were 39%, 43%, and 59%, respectively, for all bypasses, with no difference noted between above-knee and BK grafts (P = .5). At 3 years, freedom from limb loss was 75%, and patient survival was only 70%, with no adverse effect on survival imparted by amputation. Sixty-nine total adverse events occurred as a result of thrombotic occlusion (n = 51), duplex scan-detected stenosis (n = 13), or graft infection (n = 5). Forty-nine percent of all initial graft occlusions eventually led to amputation. Twenty-three grafts (27% of 86 patients) in patients maintained on chronic warfarin were subtherapeutic at the time of occlusion. Use of a distal anastomotic adjunct with BK bypasses reduced graft thrombosis (35% with vs 60% without) but did not impart a significant patency advantage (P = .07). Multivariate analysis revealed low graft flow (midgraft velocity < or =45 cm/s; odds ratio [OR], 6.1; 95% confidence interval [CI], 1.9-19.2), use of warfarin (OR, 8.4; 95% CI, 2.1-34.5), and therapeutic warfarin (OR, 24.6; 95% CI, 5.7-106) to be independently predictive for bypass patency. Graft patency was maintained in 89% of grafts remaining therapeutic on warfarin compared with only 55% of subtherapeutic or nonanticoagulated grafts (P < .001). Low-flow grafts (n = 61) occluded more frequently than higher-flow grafts (46% vs 13%; P < .001). Therapeutic warfarin augmented the patency of low-flow (P < .001) but not high-flow (P = .15) grafts.. Low graft flow was a more common mode of prosthetic bypass failure than development of duplex scan-detected stenotic lesions during follow-up. Early duplex scanning may be more important for characterizing midgraft velocity and related thrombotic potential and selecting patients for chronic anticoagulation. Maintenance of therapeutic warfarin is paramount in optimizing prosthetic bypass patency and limb preservation.

Topics: Aged; Aged, 80 and over; Amputation, Surgical; Anticoagulants; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Ischemia; Limb Salvage; Logistic Models; Lower Extremity; Male; Middle Aged; Odds Ratio; Patient Selection; Polytetrafluoroethylene; Prosthesis Design; Prosthesis Failure; Regional Blood Flow; Retrospective Studies; Risk Assessment; Risk Factors; Thrombosis; Time Factors; Treatment Failure; Ultrasonography, Doppler, Duplex; Vascular Patency; Warfarin

Topics: Anticoagulants; Aspirin; Blood Vessel Prosthesis Implantation; Chemoprevention; Clinical Trials as Topic; Female; Fibrinolytic Agents; Graft Occlusion, Vascular; Humans; Male; Netherlands; United States; United States Department of Veterans Affairs; Warfarin

The purpose of this study was to examine the outcome of patients in whom an infrainguinal bypass graft failed.. This was a retrospective analysis of consecutive patients undergoing infrainguinal bypass grafting in a single institution over 8 years.. Six hundred thirty-one infrainguinal bypass grafts were placed in 578 limbs in 503 patients during the study period. The indication for surgery was limb-threatening ischemia in 533 patients (85%); nonautologous conduits were used in 259 patients (41%), and 144 (23%) were repeat operations. After a mean follow-up of 28 +/- 1 months (median, 23 months; range, 0-99 months), 167 grafts (26%) had failed secondarily. The rate of limb salvage in patients with graft failure was poor, only 50% +/- 5% at 2 years after failure. The 2-year limb salvage rate depended on the initial indication for bypass grafting: 100% in patients with claudication (n = 16), 55% +/- 8% in patients with rest pain (n = 49), and 34% +/- 6% in patients with tissue loss (n = 73; P <.001). The prospect for limb salvage also depended on the duration that the graft remained patent. Early graft failure (<30 days; n = 25) carried a poor prognosis, with 2-year limb salvage of only 25% +/- 10%; limb salvage was 53% +/- 5% after intermediate graft failure (<2 years, n = 110) and 79% +/- 10% after late failure (>2 years, n = 15; P =.04). Multivariate analysis revealed shorter patency interval before failure (P =.006), use of warfarin sodium (Coumadin) postoperatively (P =.006), and infrapopliteal distal anastomosis (P =.01) as significant predictors for ultimate limb loss.. The overall prognosis for limb salvage in patients with failed infrainguinal bypass grafts is poor, particularly in patients with grafts placed because of tissue loss and those with early graft failure.

Topics: Aged; Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis Implantation; Female; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Intermittent Claudication; Leg; Limb Salvage; Male; Multivariate Analysis; Prognosis; Retrospective Studies; Risk Factors; Time Factors; Vascular Patency; Warfarin

Vascular access site thrombosis is a major cause of morbidity in patients receiving hemodialysis. The role of hypercoagulable states in recurrent vascular access site thrombosis remains poorly understood. Data are limited regarding systemic anticoagulation to improve access graft patency, because of concern about hemorrhagic complications. We determined the prevalence of hypercoagulable states and clinical outcome (thrombotic and hemorrhagic) after initiation of antithrombotic therapy in a series of patients with recurrent vascular access site thrombosis. We evaluated 31 patients who had sustained 119 thrombotic events that resulted in vascular access graft failure during the year before evaluation. Sixty-eight percent of patients tested had elevated concentrations of antibody to anticardiolipin or topical bovine thrombin, and 18% of patients tested had heparin-induced antibodies. More than 90% of patients had elevated factor VIII concentration, 62% had elevated fibrinogen concentrations, and 42% had elevated C-reactive protein concentrations. Twenty-nine patients were given antithrombotic therapy: 13 with warfarin sodium, 12 with unfractionated heparin (UFH), and 11 with low molecular weight heparin (LMWH). Seven patients received more than one antithrombotic agent, sequentially. Nineteen patients have had no thrombotic events since beginning antithrombotic therapy (10 with warfarin, 3 with UFH, 6 with LMWH). Mean follow-up was 8.6 months (median, 7 months). Eight patients sustained 10 bleeding complications (5 with warfarin, 3 with UFH, and 2 with LMWH). In conclusion, hypercoagulable states are common in patients with recurrent vascular access site thrombosis. Antithrombotic therapy may increase vascular access graft patency, but is associated with significant risk for hemorrhage. Prospective studies are needed to evaluate the role and safety of antithrombotic agents in improving vascular access graft patency.

Topics: Adult; Aged; Antibodies, Anticardiolipin; Arteriovenous Shunt, Surgical; Biomarkers; C-Reactive Protein; Catheters, Indwelling; Factor VIII; Female; Fibrinolytic Agents; Graft Occlusion, Vascular; Humans; Kidney Failure, Chronic; Male; Middle Aged; Prognosis; Recurrence; Renal Dialysis; Risk Assessment; Thrombosis; Treatment Outcome; Warfarin

Several drugs have been proposed to improve vascular access patency based on favorable anticoagulant, antiplatelet, or vascular-remodeling properties. However, there is little evidence to guide drug strategies.. The association between vascular access patency and the use of specific drugs was studied in a large sample of US hemodialysis patients enrolled in the Dialysis Outcomes and Practice Patterns Study, an international, prospective, observational study. In general, it was assumed that the drugs were prescribed for indications unrelated to vascular access preservation. Primary (unassisted survival) and secondary vascular access patency (assisted survival) were modeled using Cox regression (time to failure) adjusted for age, sex, race, body mass index, incidence to end-stage renal disease, diabetes mellitus, hypertension, valvular disease, chronic obstructive pulmonary disease, aortic aneurysm, deep-vein thrombosis, number of previous permanent accesses, and facility-clustering effects. Fistulae (n = 900) and grafts (n = 1,944) were evaluated separately. Technical failures within the first 30 days of surgical placement were excluded from the analysis.. Treatment with calcium channel blockers was associated with improved primary graft patency (relative risk [RR] for failure, 0.86; P = 0.034). Aspirin therapy was associated with better secondary graft patency (RR, 0.70; P < 0.001). Treatment with angiotensin-converting enzyme inhibitors was associated with significantly better secondary fistula patency (RR, 0.56; P = 0.010). Patients administered warfarin showed worse primary graft patency (RR, 1.33; P = 0.037).. These findings should help guide clinical trial priorities toward vascular access preservation using one or more of the agents that show significant risk reduction for access failure in this study.

Topics: Adult; Angiotensin-Converting Enzyme Inhibitors; Anti-Inflammatory Agents, Non-Steroidal; Anticoagulants; Arteriovenous Shunt, Surgical; Aspirin; Drug Evaluation; Graft Occlusion, Vascular; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Kidney Failure, Chronic; Longitudinal Studies; Prospective Studies; Regression Analysis; Renal Dialysis; Risk Factors; Treatment Failure; Treatment Outcome; Vascular Patency; Vasodilator Agents; Warfarin

The present study, which aimed to determine the predictors of distal embolization and restenosis after stenting for vein graft disease, retrospectively analyzed 51 consecutive patients who underwent stent implantation for diseased saphenous vein grafts. Follow-up angiography was performed 6 months after the procedure and the clinical and angiographic variables were analyzed by multivariate logistic regression to determine the predictors of distal embolization and restenosis. Initial clinical success was achieved in 49 patients, 44 of whom underwent follow-up angiography and were enrolled in the retrospective analysis. Distal embolization occurred in 6 grafts (13.6%). Multivariate analysis showed that the lesion length and the total cholesterol level were independent predictors of distal embolization. Angiographic restenosis occurred in 13 (26.5%) of 49 lesions. The minimum luminal diameter and the percent diameter stenosis after stenting were associated with the occurrence of restenosis. Multivariate analysis of lesions located in the graft body identified graft age as an independent predictor of restenosis. Distal embolization can occur after vein graft stenting, especially in patients with hypercholesterolemia and diffuse stenosis. The post-stenting minimum luminal diameter and the percent diameter stenosis are predictors of restenosis. In particular, graft age is associated with the restenosis of graft body lesions.

Topics: Aged; Anticoagulants; Aspirin; Catheterization; Combined Modality Therapy; Comorbidity; Coronary Angiography; Coronary Artery Bypass; Coronary Disease; Drug Therapy, Combination; Embolism; Female; Fibrinolytic Agents; Follow-Up Studies; Graft Occlusion, Vascular; Heparin; Humans; Japan; Male; Middle Aged; Recurrence; Retrospective Studies; Risk Factors; Saphenous Vein; Stents; Ticlopidine; Treatment Outcome; Warfarin

Vascular access-related complications are an important cause of morbidity, and they account for 14% to 17% of dialysis patients' hospitalizations with an annual cost in the United States of approximately $1 billion. Previous studies have related the major predisposing factor of thrombotic complications to stenosis of the graft anastomosis. Several recent reports suggest that antiphospholipid antibodies may cause frequent thrombotic complications. The broad spectrum of diseases that cause hypercoagulable states has not been correlated with frequent PTFE graft thrombosis.. A retrospective case series study was performed to determine the frequency of hypercoagulable states in dialysis patients who had repeated thrombotic complications of their PTFE grafts. Between May 1996 and June 1998, 91 operations were performed on 34 patients with end-stage renal disease. All arteriovenous fistulas were created with PTFE grafts and placed by a single surgeon. All patients were evaluated at operation for anastomotic stenosis, and the majority of patients were studied for hypercoagulable states. Patients with a documented hypercoagulable state were considered for warfarin therapy.. Twenty-two individuals (64.7%) developed 67 thrombotic complications. Twelve of the 14 patients tested (85.7%) were shown to have hypercoagulable states of various causes and degrees. Thirteen patients developed multiple thrombotic complications, 11 (81.8%) were tested and proved to be hypercoagulable. Thirty-eight of the thrombotic complications had nonanatomic causes and 28 (41.8%) had hypercoagulability as the only determinable cause. Ten of the 12 hypercoagulable patients (83.3%) were relegated to intermediate to high-intensity warfarin therapy to reduce the incidence of thrombotic events. Hypercoagulable patients not receiving warfarin had a thrombosis rate of 4.0 events per year; patients on warfarin had a rate of 1.2 events per year. Twenty-three thrombotic events occurred in the anticoagulated group all with an International Normalized Ratio (INR) less than 2.7. This incidence of vascular access thrombosis may be prevented when patients are maintained at an optimal INR of 2.7-3.0.. Hypercoagulability has been a major etiologic factor in PTFE graft thrombosis. Hypercoagulable states are often found in patients with multiple graft thromboses and in patients with nonanatomic causes for thrombosis. Antiphospholipid antibodies are prevalent in the patients with PTFE graft thrombosis, as well as abnormalities in the Protein-C, Protein-S, and Antithrombin III systems. PTFE graft thrombosis has been a frequent cause of morbidity in patients on hemodialysis, and diagnostic evaluation should include a hypercoagulability profile. Based on our data, warfarin therapy should be instituted when hypercoagulable states are found, unless otherwise contraindicated, and INR maintained at 2.7-3.0 to decrease morbidity and frequency of graft thrombosis.

Topics: Adult; Aged; Aged, 80 and over; Anticoagulants; Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis; Female; Graft Occlusion, Vascular; Humans; Incidence; Kidney Failure, Chronic; Male; Middle Aged; Polytetrafluoroethylene; Renal Dialysis; Retrospective Studies; Thrombophilia; Thrombosis; Warfarin

From November 1, 1995, to April 30, 1997, in our outpatient dialysis facility, 7,179 or 24.3% of hemodialyses were performed with soft, cuffed, intravenous catheters as blood accesses. Inadequate blood flow (pump speed < 400 mL/min) was noted in 286 instances (4.0%). Locking of catheter lumina with 5,000 to 9,000 IU urokinase was only partly successful in three of 21 cases. Infusions of 20,000 to 40,000 IU urokinase in 25 instances during dialysis restored catheter function in 10 cases. In nine instances in which blood could not be aspirated from the catheter and dialysis could not be performed, the infusion was done through the catheter while the patient remained in the chair. In eight instances, the catheter was opened, and dialysis was performed on the next shift. In 162 instances, a new method was used to open failing catheters most conveniently, efficiently, and with minimal cost. Whenever a nonpositional deterioration of blood flow was noted, 250,000 IU urokinase was infused during dialysis over 3 hours, if there were no contraindications. Full restoration of pump speed was achieved during 132 infusions; in another 21 cases, blood flow improved. In 59 cases, in which an adequate pump speed was not achieved during the next dialysis, the infusion was repeated with restoration of blood flow in 50 instances and flow improvement in six; infusion was re-repeated in the nine instances without complete restoration of flow and in one of the 50 in which restoration of flow was temporary. Adequate flow was restored in nine of these 10 cases in which re-repeated infusion was done. Routine doses of heparin were used concomitantly with urokinase in all cases. No adverse reaction to urokinase has been encountered in any case. To maintain long-term catheter patency, warfarin therapy was started in patients who required repeated urokinase infusions. Vials of 250,000 IU, 9,000 IU, and 5,000 IU urokinase cost $358.47, $77.07, and $43.76, respectively. The higher cost of high-dose intradialytic urokinase as compared with the catheter "lock" is offset by the high probability of positive results, saving of nursing and patient time, and saving on transportation expenses. The convenience and cost are even more remarkably in favor of intradialytic urokinase compared with catheter stripping ($2,433) or surgical replacement ($3,060).

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anticoagulants; Catheterization, Central Venous; Catheters, Indwelling; Female; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Plasminogen Activators; Renal Dialysis; Thrombosis; Urokinase-Type Plasminogen Activator; Vascular Patency; Warfarin

Topics: Anticholesteremic Agents; Anticoagulants; Cholestyramine Resin; Clinical Trials as Topic; Coronary Artery Bypass; Graft Occlusion, Vascular; Humans; Hypolipidemic Agents; Lovastatin; Warfarin

Activated protein C resistance caused by factor V Leiden is an important thrombophilia disorder which predisposes to venous thromboembolism. Some studies also suggest a role in the pathogenesis of arterial thrombosis and atherosclerosis. The authors have investigated the prevalence of activated protein C resistance and factor V Leiden in a series of 45 patients with peripheral vascular disease. Twelve patients were receiving warfarin. The activated protein C resistance ratios were significantly lower in the group of 33 non-warfarinized patients with peripheral vascular disease (median 2.82 (range 1.36-3.83)) compared with 33 age- and sex-matched controls (median 2.97 range 2.24-4.11); P<0.005; Wilcoxon rank sum). Eight patients (24%) had activated protein C resistance (ratio <2.2). The prevalence of factor V Leiden in patients with peripheral vascular disease was 17.8% (8/45). This is significantly increased compared with the local population and UK published frequency of 3.5% for this genotype. The presence of factor V Leiden did not affect the late outcome of arterial reconstructive surgery in terms of graft patency (P=0.5, Fisher's Exact test).

Topics: Aged; Arteriosclerosis; Blood Coagulation Tests; Enzyme Activation; Factor V; Female; Graft Occlusion, Vascular; Humans; Ischemia; Leg; Male; Middle Aged; Protein C; Reoperation; Risk Factors; Warfarin

Two patients experienced upper extremity thromboembolism after axillary-axillary bypass grafting (AxAG) for symptomatic subclavian artery stenosis. The first patient, a 67-year-old male, presented with left upper extremity thromboembolism 3 years after AxAG with 8 mm externally support PTFE. An arteriogram revealed a patent AxAG, thrombus in the proximal left subclavian arterial stump just distal to its occlusion, and multiple digital artery emboli. The patient was treated with warfarin for 8 months, with resolution of symptoms. The second patient, a 57-year-old male, occluded his AxAG (8 mm knitted Dacron) with minimal return of symptoms. Non-operative treatment was elected and 4 years later the patient presented with right upper extremity (donor side) thromboembolism. Arteriography revealed occlusion of the AxAG, radial artery, and digital arteries of the index, long and ring fingers. Thrombolytic therapy of the right arm was undertaken with minimal improvement. Subsequent detachment of the AxAG and placement of an interposition reversed saphenous vein graft was performed. Both patients continue to be asymptomatic during follow-up of 4.7 and 2.0 years, respectively.

Topics: Aged; Anticoagulants; Arm; Arterial Occlusive Diseases; Axillary Artery; Blood Vessel Prosthesis; Constriction, Pathologic; Embolism; Fingers; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Polytetrafluoroethylene; Postoperative Complications; Radial Artery; Saphenous Vein; Subclavian Artery; Thromboembolism; Thrombolytic Therapy; Thrombosis; Warfarin

Topics: Anticoagulants; Combined Modality Therapy; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Saphenous Vein; Stents; Thrombosis; Warfarin

Topics: Acute Disease; Adult; Aorta, Abdominal; Female; Graft Occlusion, Vascular; Heparin; Humans; Hypertension, Renovascular; Radiology, Interventional; Renal Artery; Saphenous Vein; Thrombectomy; Thrombosis; Warfarin

Graft patency is a major factor contributing to the long-term results of coronary artery bypass graft (CABG) surgery. The systematic overview of the Antiplatelet Trialists' Collaboration provides unequivocal evidence that antiplatelet therapy reduces by nearly one-half the odds of coronary graft occlusion following CABG. We retrospectively reviewed patients undergoing CABG during 1993 at the Cardiothoracic Unit, Northern General Hospital, to determine the incidence of, and indications for, aspirin omission following CABG: 462 patients with isolated CABG, 75 patients with a combined CABG and a heart valve procedure and 21 patients with a combined CABG and other non-valve procedure. Thirty-six patients (7.5%) with isolated CABG and CABG combined with a non-valve procedure were not prescribed aspirin. The reasons for aspirin omission were categorized into three groups depending on whether omission was fully justified (group 1), possibly justified (group 2) or unjustified (group 3). Twenty-one patients were in groups 2 and 3, nine of whom were started on aspirin 2-6 weeks after discharge without any ill effect. Forty-two patients were discharged from hospital on a three month course of warfarin. Four months later four patients had died, 24 had changed to aspirin, 10 were still on warfarin and four were on neither drug. Aspirin was sometimes omitted without clear indications. Better provisions for supervision should be made by either the General Practitioner or Hospital Practitioner during the change-over period from oral anticoagulation to antiplatelet therapy in patients on a short course of warfarin.

Topics: Anticoagulants; Aspirin; Coronary Artery Bypass; Drug Administration Schedule; Follow-Up Studies; Graft Occlusion, Vascular; Humans; Vascular Patency; Warfarin

Topics: Aspirin; Coronary Artery Bypass; Graft Occlusion, Vascular; Humans; Postoperative Complications; Time Factors; Warfarin

This study was performed to clarify the role of intraarterial thrombolytic therapy (IATT) in the management of acute lower extremity ischemia.. A retrospective review of 77 patients undergoing 84 courses of high-dose regional urokinase IATT from July 1981 to June 1991 was performed. The group included patients with acute thrombosis of lower extremity bypass grafts (n = 48) or native arteries (n = 36), presenting with ischemic but viable limbs, minimal or no motor dysfunction, and an absence of muscle rigor or compartment syndrome. The data were then examined individually by site of thrombosis to evaluate patient selection for IATT.. Complete lysis, complications (either distal thromboembolism or bleeding), and early limb loss occurred in 59.5%, 11%, and 6% of infusions, respectively. IATT precluded the need for operative intervention in 49% of acutely ischemic limbs. When surgery was required, successful IATT precisely localized responsible lesions and reduced the magnitude of operation. A subset of 13 patients were identified in whom either no intrinsic abnormality or poor runoff were evident after lysis and were treated with anticoagulation alone.. These data show IATT to be especially suitable for thrombosis of native iliac or femoropopliteal arteries and infrainguinal vein grafts. IATT serves primarily as an adjunct in management of acute lower extremity ischemia. After successful IATT, subsequent therapy can be tailored to the anatomic cause of thrombosis.

Topics: Femoral Artery; Graft Occlusion, Vascular; Humans; Iliac Artery; Infusions, Intra-Arterial; Ischemia; Leg; Popliteal Artery; Retrospective Studies; Thrombolytic Therapy; Thrombosis; Urokinase-Type Plasminogen Activator; Warfarin

We treated a coronary artery bypass patient whose postoperative course was complicated by heparin-induced thrombocytopenia and resultant pulmonary artery and saphenous vein graft thromboses. The pulmonary thromboemboli were found first, and pulmonary blood flow was restored with intravenously administered tissue plasminogen activator (tPA). A short time later, the vein grafts were found to be occluded, and we subsequently performed multivessel percutaneous transluminal coronary angioplasty (PTCA) using tPA as an adjuvant to oral warfarin sodium therapy with excellent results. We conclude that heparin-induced thromboses in the pulmonary arteries are amenable to thrombolytic therapy, including tPA, whereas this regimen appears to have little effect on saphenous vein grafts. We also found that a combination of warfarin and thrombolytic therapy is an alternative regimen for heparin-intolerant patients who require PTCA.

Topics: Angioplasty, Balloon, Coronary; Coronary Artery Bypass; Graft Occlusion, Vascular; Heparin; Humans; Male; Middle Aged; Pulmonary Embolism; Saphenous Vein; Thrombocytopenia; Thrombolytic Therapy; Thrombosis; Tissue Plasminogen Activator; Warfarin

To evaluate the pathogenesis of thrombosis formation in synthetic venous grafts, the inferior vena cava of rabbits were replaced by woven Tetron (polyethylene terephtalate) grafts. Six animals were assigned as controls without medication (Group A), and 48 animals were randomly assigned to experimental groups as follows: ticlopidine hydrochloride (100 mg/kg/day) was administered orally from 5 days prior to operation to the end of the experiment (Group B); warfarin sodium (0.33 mg/kg/day) was given orally for the same period (Group C); and a combination of ticlopidine hydrochloride (50 mg/kg/day) and warfarin sodium (0.16 mg/kg/day) was administered for the same period (Group D). All the grafts in group A occluded within 3 h. All grafts harvested from groups B and D remained patent at least until the twenty-eighth day after grafting but the lumen was narrowed by intimal hyperplasia. Although the grafts from group C were patent at the seventh day, all grafts occluded with intimal hyperplasia on day 14 and day 28. The dry weight of thrombus in the graft in group B and group D was 39 +/- 3 mg and 30 +/- 2 mg, respectively on day 28. These figures were significantly lower than that of the control group 59 +/- 9 mg at 5 h after the initial heparinisation. Ultrastructural studies with scanning electron microscopy showed that the thrombus in the graft of the control group was composed of platelet aggregates anchored to synthetic fibres and of erythrocytes entrapped in the fibrin network. By day 7, in the groups modified with drugs, sheets of endothelial-like cells extended across both suture lines from the host stumps and extended to the middle of the graft thereafter. Light microscopy revealed that the initimal hyperplasia in groups B, C and D on day 28 were mainly composed of fibroblasts, myoblasts, collagenous fibres and micro-capillaries.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Blood Vessel Prosthesis; Graft Occlusion, Vascular; Male; Microscopy, Electron, Scanning; Platelet Aggregation; Rabbits; Thrombosis; Ticlopidine; Time Factors; Vena Cava, Inferior; Warfarin

This study was done to evaluate the effect of aspirin (ASA), dipyridamole (DIP), and warfarin on 406 patients who had femoropopliteal-tibial operations with saphenous vein (SV), umbilical vein (UV), polytetrafluoroethylene (PTFE) and Dacron (DuPont, Wilmington, DE). Above-knee bypasses were performed in 181 patients: 77 were taking ASA and DIP at the time of operation, 41 were placed on postoperative "low-dose" warfarin, whereas 63 did not receive adjunctive medications. Late patency demonstrated no significant difference among the groups based on graft material used (SV 71%, UV 68%, PTFE 66%, and Dacron 65%) (P less than .25). Below-knee femoro-popliteal bypasses were performed in 183 patients: 82 were taking ASA and DIP at the time of operation, 40 were placed on warfarin postoperatively and no medications were given to 41 patients. Late patency rates (39 months) demonstrated that SV (62%) was superior to UV (51%), PTFE (30%), and Dacron (18%) (P less than .01). Femorotibial-peroneal bypasses were done in 42 patients: 13 patients were taking ASA and DIP at operation, 21 were placed on warfarin postoperatively and 8 received no medication. SV late patency (33 months) was again superior (43%) to UV (31%); no PTFE or Dacron grafts functioned after 24 months. Patients who took warfarin and ASA had the best early (16 months) patency results. Above-knee prosthetic grafts achieved late patency rates similar to SV while reducing operative time, shortening recuperation, and sparing the saphenous vein for use in the coronary or infrapopliteal vessels. In below-knee bypasses SV was superior to prosthetic grafts, with or without the use of ASA and DIP or warfarin.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; Aged, 80 and over; Arteriosclerosis Obliterans; Arteriovenous Shunt, Surgical; Aspirin; Blood Vessel Prosthesis; Dipyridamole; Drug Evaluation; Female; Femoral Artery; Graft Occlusion, Vascular; Humans; Male; Middle Aged; Popliteal Artery; Retrospective Studies; Saphenous Vein; Thrombosis; Umbilical Veins; Warfarin

Platelet deposition can occur in areas of vascular damage and on prosthetic materials such as heart valves or grafts; mural thrombus formation, with eventual organization, progression to fatal occlusion, thrombolysis, or arterial embolization can follow. Use of antiplatelet drugs in patients undergoing certain cardiovascular surgical procedures or having rapid progression of atherosclerosis may reduce the thromboembolic risk.

Topics: Angioplasty, Balloon; Anticoagulants; Aspirin; Bioprosthesis; Blood Platelets; Coronary Disease; Dipyridamole; Double-Blind Method; Drug Therapy, Combination; Graft Occlusion, Vascular; Heart Valve Prosthesis; Heparin; Humans; Prothrombin Time; Random Allocation; Sulfinpyrazone; Thromboembolism; Time Factors; Warfarin