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PloS One 2023Abrupt thrombosis is a form of thrombosis that occurs unexpectedly and without being preceded by hemodialysis fistula (AVF) dysfunction during dialysis. We found that...
Characterization of hemodialysis fistulas experienced abrupt thrombosis and determination of a proper follow-up protocol: A retrospective cohort study and an interventionist's perspective.
Abrupt thrombosis is a form of thrombosis that occurs unexpectedly and without being preceded by hemodialysis fistula (AVF) dysfunction during dialysis. We found that AVFs with a history of abrupt thrombosis (abtAVF) appeared to have more episodes of thrombosis and required more frequent interventions than those without such history. Therefore, we sought to characterize the abtAVFs and examined our follow-up protocols to determine which one is optimal. We performed a retrospective cohort study using routinely collected data. The thrombosis rate, AVF loss rate, thrombosis-free primary patency, and secondary patency were calculated. Additionally, the restenosis rates of the AVFs under the follow-up protocol/sub-protocols and the abtAVFs were determined. The thrombosis rate, procedure rate, AVF loss rate, thrombosis-free primary patency, and secondary patency of the abtAVFs were 0.237/pt-yr, 2.702/pt-yr, 0.027/pt-yr, 78.3%, and 96.0%, respectively. The restenosis rate for AVFs in the abtAVF group and the angiographic follow-up sub-protocol were similar. However, the abtAVF group had a significantly higher thrombosis rate and AVF loss rate than AVFs without a history of abrupt thrombosis (n-abtAVF). The lowest thrombosis rate was observed for n-abtAVFs, followed up periodically under the outpatient or angiographic sub-protocols. AVFs with a history of abrupt thrombosis had a high restenosis rate, and periodic angiographic follow-up with a mean interval of 3 months was presumed appropriate. For selected populations, such as salvage-challenging AVFs, periodic outpatient or angiographic follow-up was mandatory to extend their usable lives for hemodialysis.
Topics: Humans; Renal Dialysis; Retrospective Studies; Follow-Up Studies; Vascular Patency; Arteriovenous Shunt, Surgical; Thrombosis; Fistula; Treatment Outcome
PubMed: 36913383
DOI: 10.1371/journal.pone.0282891 -
European Respiratory Review : An... Dec 2012Pulmonary arterial hypertension (PAH) is a common complication of congenital heart disease (CHD), with most cases occurring in patients with congenital cardiac shunts.... (Review)
Review
Pulmonary arterial hypertension (PAH) is a common complication of congenital heart disease (CHD), with most cases occurring in patients with congenital cardiac shunts. In patients with an uncorrected left-to-right shunt, increased pulmonary pressure leads to vascular remodelling and dysfunction, resulting in a progressive rise in pulmonary vascular resistance and increased pressures in the right heart. Eventually, reversal of the shunt may arise, with the development of Eisenmenger's syndrome, the most advanced form of PAH-CHD. The prevalence of PAH-CHD has fallen in developed countries over recent years and the number of patients surviving into adulthood has increased markedly. Today, the majority of PAH-CHD patients seen in clinical practice are adults, and many of these individuals have complex disease or received a late diagnosis of their defect. While there have been advances in the management and therapy in recent years, PAH-CHD is a heterogeneous condition and some subgroups, such as those with Down's syndrome, present particular challenges. This article gives an overview of the demographics, pathophysiology and treatment of PAH-CHD and focuses on individuals with Down's syndrome as an important and challenging patient group.
Topics: Antihypertensive Agents; Bosentan; Clinical Trials as Topic; Comorbidity; Down Syndrome; Eisenmenger Complex; Endothelium, Vascular; Epoprostenol; Health Behavior; Heart Defects, Congenital; Heart Transplantation; Humans; Hypertension, Pulmonary; Lung Transplantation; Oxygen Inhalation Therapy; Phosphodiesterase 5 Inhibitors; Piperazines; Practice Guidelines as Topic; Pulmonary Circulation; Purines; Sildenafil Citrate; Sulfonamides; Sulfones; Thrombosis
PubMed: 23204121
DOI: 10.1183/09059180.00004712 -
Clinical Journal of the American... Aug 2009Patients with end stage renal disease (ESRD) are often prescribed antiplatelet medications. However, these patients are also at increased risk of bleeding compared with... (Review)
Review
BACKGROUND AND OBJECTIVES
Patients with end stage renal disease (ESRD) are often prescribed antiplatelet medications. However, these patients are also at increased risk of bleeding compared with the general population, and an aim was made to quantify this risk with antiplatelet agents.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
A systematic review of the literature (Medline, EMBASE, Cochrane CENTRAL and Google Scholar databases) was done to determine the bleeding risk in ESRD patients prescribed antiplatelet therapy. The secondary outcome was the effect on access thrombosis. All case series, cohort studies and clinical trials were considered if they included ten or more ESRD patients, assessed bleeding risk with antiplatelet agents, and lasted for more than 3 mo.
RESULTS
Sixteen studies, including 40,676 patients, were identified that met predefined inclusion criteria. Due to study heterogeneity and weaknesses in methodology, bleeding rates were not pooled across studies. However, the bleeding risk appears to be increased for hemodialysis patients treated with combination antiplatelet therapy. The results are mixed for studies using a single antiplatelet agent. Antiplatelet agents appear to be effective in preventing shunt and central venous catheter thrombosis, but not for preventing thrombosis of arteriovenous grafts.
CONCLUSION
The risks and benefits of antiplatelet agents in ESRD patients remain poorly defined. Until a clinical trial addresses this in the dialysis population, individual risk stratification taking into account the increased risk of bleeding should be considered before initiating antiplatelet agents, especially in combination therapy.
Topics: Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis Implantation; Catheterization, Central Venous; Drug Therapy, Combination; Hemorrhage; Humans; Kidney Failure, Chronic; Platelet Aggregation Inhibitors; Renal Dialysis; Risk Assessment; Thrombosis; Treatment Outcome
PubMed: 19578002
DOI: 10.2215/CJN.00810209 -
Liver Transplantation : Official... Nov 20061. Diagnosis of Budd-Chiari syndrome can be made on the basis of radiological imaging alone without the need for liver biopsy. 2. Ultrasonography, computed tomography,... (Review)
Review
1. Diagnosis of Budd-Chiari syndrome can be made on the basis of radiological imaging alone without the need for liver biopsy. 2. Ultrasonography, computed tomography, and magnetic resonance imaging all show various degrees of occlusion of the hepatic veins and/or inferior vena cava. Hypertrophy of the caudate lobe may also be seen. 3. Computed tomographic and magnetic resonance imaging give a better idea of hepatic perfusion. Image reconstruction of the inferior vena cava is also possible. 4. Hepatic venography demonstrates a spiderweb pattern diagnostic of Budd-Chiari syndrome. 5. Pressure measurements in the portal vein and infrahepatic inferior vena cava are necessary to determine whether a surgical portosystemic shunt will be successful. 6. Transjugular intrahepatic portosystemic shunt provides definitive treatment in many patients; this is not discussed.
Topics: Anticoagulants; Budd-Chiari Syndrome; Humans; Liver Transplantation; Portasystemic Shunt, Transjugular Intrahepatic; Radiography; Stents
PubMed: 17051559
DOI: 10.1002/lt.20939 -
JACC. Cardiovascular Interventions Jan 2010More than 1 in 1,000 patients in the U.S. has end-stage renal disease, and most patients who require renal-replacement therapy undergo hemodialysis. By the year 2020,... (Review)
Review
More than 1 in 1,000 patients in the U.S. has end-stage renal disease, and most patients who require renal-replacement therapy undergo hemodialysis. By the year 2020, more than 750,000 patients are expected to have end-stage renal disease, and over 500,000 will require hemodialysis. The greatest limitation of hemodialysis is the finite durability of hemodialysis accesses, which on average remain patent for <3 years but are the lifeline for hemodialysis patients. Catheter-based interventions are successful in restoring flow in more than 80% of hemodialysis accesses that undergo thrombosis and have replaced surgical revision as the treatment of choice for failing or thrombosed accesses. Catheter-based interventions have improved the quality of life for hemodialysis patients by reducing the need for temporary hemodialysis catheters and have prolonged total survival time by preserving existing access sites and by saving venous segments for future access creation. This review discusses the pathophysiology of dialysis access failure, presents the success rates of catheter-based treatments, and illustrates the interventional approaches for treating failing and thrombosed fistulas and grafts.
Topics: Angioplasty, Balloon; Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis Implantation; Cardiovascular Agents; Graft Occlusion, Vascular; Humans; Kidney Failure, Chronic; Phlebography; Quality of Life; Radiography, Interventional; Renal Dialysis; Thrombectomy; Thrombosis; Time Factors; Treatment Outcome; Upper Extremity; Vascular Patency
PubMed: 20129561
DOI: 10.1016/j.jcin.2009.10.021 -
Kidney International Jan 2012Hemodialysis vascular access surveillance continues to be widely recommended despite ongoing controversy as to its benefit in prolonging access patency compared with... (Review)
Review
Hemodialysis vascular access surveillance continues to be widely recommended despite ongoing controversy as to its benefit in prolonging access patency compared with clinical monitoring alone. The most common screening tests are access blood flow and dialysis venous pressure measurements. When surveillance test results cross a predetermined threshold, accesses are referred for intervention with correction of stenosis to reduce future thrombosis and prolong access survival. Current surveillance strategies have four components: (1) underlying condition; (2) screening test; (3) intervention; and (4) outcomes. However, limitations exist within each component that may prevent achieving the desired outcomes. This review discusses these limitations and their consequences. To date, randomized controlled trials have not consistently shown that surveillance improves outcomes in grafts, and there is limited evidence that surveillance reduces thrombosis without prolonging the life of native fistulae. In conclusion, current evidence does not support the concept that all accesses should undergo routine surveillance with intervention.
Topics: Arteriovenous Shunt, Surgical; Constriction, Pathologic; Graft Occlusion, Vascular; Humans; Kidney Failure, Chronic; Practice Guidelines as Topic; Renal Dialysis; Thrombosis
PubMed: 21975864
DOI: 10.1038/ki.2011.337 -
Liver Transplantation : Official... Mar 2003Transjugular intrahepatic portosystemic shunts (TIPS) have been used in the treatment of complications of portal hypertension. TIPS is used for the control of acute... (Review)
Review
Transjugular intrahepatic portosystemic shunts (TIPS) have been used in the treatment of complications of portal hypertension. TIPS is used for the control of acute variceal bleeding and for the prevention of vericeal rebleeding when pharmacologic therapy and endoscopic therapy have failed. Patients with refractory ascites with adequate hepatic reserve and renal function who fail to respond to large volume paracentesis may be reasonable candidates for TIPS. Promising indications for TIPS are Budd-Chiari syndrome uncontrolled by medical therapy, severe portal hypertensive gastropathy, refractory hepatic hydrothorax, and hepatorenal syndrome. TIPS cannot be recommended for preoperative portal decompression solely to facilitate liver transplantation. Special care should be taken to insure proper placement of the stent to avoid increasing the technical difficulty of the transplantation procedure. The major limiting factors for TIPS success are shunt dysfunction and hepatic encephalopathy. Because shunt stenosis is the most important cause of recurrent complications of portal hypertension, a surveillance program to monitor shunt patency is mandatory. The MELD score may be useful in predicting post-TIPS survival, and also in counseling patients and their families.
Topics: Budd-Chiari Syndrome; Humans; Hypertension, Portal; Portasystemic Shunt, Transjugular Intrahepatic; Randomized Controlled Trials as Topic
PubMed: 12619016
DOI: 10.1053/jlts.2003.50045 -
Current Hypertension Reports Oct 2011Establishing whether large vessel occlusive disease threatens tissue oxygenation and viability in the post-stenotic kidney is difficult for clinicians. Development of... (Review)
Review
Establishing whether large vessel occlusive disease threatens tissue oxygenation and viability in the post-stenotic kidney is difficult for clinicians. Development of blood oxygen level-dependent (BOLD) MRI methods can allow functional evaluation of regional differences in deoxyhemoglobin levels within the kidney without requiring contrast. The complex renal circulation normally provides a gradient of oxygenation from a highly vascular cortex to much reduced levels in the deep sections of medulla, dependent upon adjustments in renal afferent arterioles, oxygen consumption related to solute transport, and arteriovenous shunting related to the juxtaposition of descending and ascending vasa recta. Studies with BOLD imaging have identified adaptation to substantial reductions in renal blood flow, volume, and glomerular filtration rate in post-stenotic kidneys that preserves medullary and cortical oxygenation during medical therapy. However, extreme vascular compromise overwhelms these adaptive changes and leads to cortical hypoxia and microvascular injury.
Topics: Glomerular Filtration Rate; Humans; Hypertension, Renovascular; Hypoxia; Kidney; Magnetic Resonance Imaging; Oxidative Stress; Oxygen; Oxygen Consumption; Renal Artery Obstruction; Thrombosis
PubMed: 21833688
DOI: 10.1007/s11906-011-0218-7 -
The Journal of Extra-corporeal... Sep 2006Combined anti-platelet-anticoagulant therapy is increasingly being used to reduce the risk of device-induced thrombosis and thromboembolism. However, direct quantitative...
Combined anti-platelet-anticoagulant therapy is increasingly being used to reduce the risk of device-induced thrombosis and thromboembolism. However, direct quantitative confirmation of the effectiveness of this combination approach is lacking. This study was undertaken to quantify the effects of various combinations of heparin (anticoagulant) and tirofiban (antiplatelet agent) on device-induced thrombosis and thromboembolism using a coronary stent as a prototype device. Adult sheep were implanted with ex vivo carotid-carotid shunts containing replaceable tubing segments in which nitinol stents were deployed. Nine combinations of heparin (average activated clot time = 129, 199, and 355 seconds) and tirofiban (0%, 50%, and 100% platelet inhibition) were tested at random with three replicates per animal. Thrombus weight on the stent at the end of each experiment (1 hour) was measured, and emboli released from the stent were continuously monitored during the experiment using a light scattering microemboli detector. With no tirofiban, increasing the heparin concentration was associated with a decreased endpoint thrombus weight (p < .05) but with a slight (non-significant) increase in the number of downstream thromboemboli. However, the presence of tirofiban decreased both thrombus weight and thromboemboli numbers (p < .05), regardless of the heparin concentration. In the presence of medium or high tirofiban, an increase of heparin from low to medium levels also decreased both thrombus weight and thromboemboli numbers (p < .05). Heparin alone does not provide adequate protection against thromboembolism (and may actually increase it by reducing thrombus cohesive strength). However, the combination of heparin and tirofiban is effective in reducing both thrombus and thromboemboli, and an optimal combination may exist.
Topics: Animals; Anticoagulants; Drug Therapy, Combination; Heparin; In Vitro Techniques; Male; Platelet Aggregation Inhibitors; Sheep; Stents; Thromboembolism; Thrombosis; Tirofiban; Tyrosine
PubMed: 17089509
DOI: No ID Found -
Alimentary Pharmacology & Therapeutics Mar 2006Treatment options for patients with portal vein thrombosis are limited.
BACKGROUND
Treatment options for patients with portal vein thrombosis are limited.
AIM
To evaluate the feasibility and efficacy of transjugular intrahepatic portosystemic shunt for portal vein thrombosis with/without cavernomatous transformation.
METHODS
A survey of such patients, referred for transjugular intrahepatic portosystemic shunt between 1994 and 2005, was performed. Success rates, complications, transjugular intrahepatic portosystemic shunt patency and clinical progression were examined.
RESULTS
Transjugular intrahepatic portosystemic shunt was attempted in 28 patients (13 cirrhotics). Indications were: presurgery/transplantation (2), worsening of ascites (2), variceal bleeding (15 - 8 elective), refractory ascites (3), portal biliopathy (3) and portal vein thrombosis complicating Budd-Chiari syndrome (2). Transjugular intrahepatic portosystemic shunt was placed successfully in 19 of 28 (73%); 23 of 28 had complete portal vein thrombosis and 9 of 23 had cavernous transformation and transjugular intrahepatic portosystemic shunt was successfully placed in six of these. In the 19 patients with transjugular intrahepatic portosystemic shunt, the mean follow-up was 18.1 months (range 5-70): six patients had stent revisions; three had liver transplantation, one died of bleeding. Most cirrhotic patients had an improvement in the Child-Pugh score. In the failed transjugular intrahepatic portosystemic shunt group, two of nine died, and three had further bleeding.
CONCLUSIONS
Transjugular intrahepatic portosystemic shunt should be considered for selected patients with symptomatic complete portal vein thrombosis with/without cavernous transformation, as clinical improvement and less rebleeding occur when transjugular intrahepatic portosystemic shunt placement is successful.
Topics: Adolescent; Adult; Aged; Anticoagulants; Cohort Studies; Emergencies; Feasibility Studies; Female; Humans; Hypertension, Portal; Male; Middle Aged; Portal Vein; Portasystemic Shunt, Surgical; Radiography; Stents; Treatment Failure; Treatment Outcome; Venous Thrombosis
PubMed: 16556179
DOI: 10.1111/j.1365-2036.2006.02820.x