Alteplase as an alternative to urokinase. Advisory Panel on Catheter-Directed Thrombolytic Therapy

Hepatic artery vasospasm masquerading as early hepatic artery thrombosis in progressive familial intrahepatic cholestasis 3: a case report

Post-liver transplant (LT) hepatic artery vasospasm is a vascular complication that is not well recognized and its incidence is not known. As a possible sequela to vasospasm, hepatic artery thrombosis is the second major cause of allograft failure after primary nonfunction and its reported incidence is 2.9% in adults and 8.3% in pediatric LT. Lacuna in knowledge regarding early hepatic artery vasospasm post-LT makes it a difficult condition to diagnose and treat, as the initial ischemic insult on graft can have devastating consequences. We report a case of pediatric progressive familial intrahepatic cholestasis type 3-related chronic liver disease who underwent cadaveric orthotopic LT and postoperatively developed fever, worsening hypotension, and elevated liver enzymes with an absence of arterial flow in intrahepatic branches on Doppler ultrasound. Suspecting early hepatic artery thrombosis, the patient was re-explored and the graft hepatic artery was found to be in a state of vasospasm. Following the infusion of intra-arterial papaverine, urokinase, and intravenous nicorandil, there was an improvement in blood flow. The patient responded well and was discharged on postoperative day 23 with normal liver enzymes.

Major Bleeding During Thrombolytic Therapy for Acute Lower Limb Ischaemia: Value of Laboratory Tests for Clinical Decision Making, 17 Years of Experience

OBJECTIVE

Regular measurement of fibrinogen as dose guidance in catheter directed thrombolysis (CDT) for acute limb ischaemia (ALI) has recently been dropped from European guidelines based on inconsistent literature. This study aimed to determine whether low fibrinogen levels and high activated partial thromboplastin time (APTT) are associated with an increased major bleeding risk during CDT.

METHODS

All consecutive patients treated with CDT for ALI in two Dutch hospitals between January 2004 and April 2021 were analysed retrospectively. Patients were treated with two dosing regimens (low dose: 50 000 IU/hour; high dose: 100 000 IU/hour) of urokinase and, after 2018, with a single low dose regimen of alteplase (rtPA) due to urokinase manufacturing problems. The incidence of major bleeding and associated APTT and fibrinogen levels were reviewed from patient charts.

RESULTS

Of the 443 included cases, 277 underwent CDT with urokinase and 166 with rtPA. The incidence of major bleeding in the whole cohort was 7%. Patients with a fibrinogen levels < 1.0 g/L developed more major bleeding than those in whom the fibrinogen level did not drop below 1.0 g/L (15% vs. 6%; p = .041). Systemic heparinisation during CDT or high (> 80 seconds) APTT were not significantly associated with major bleeding. Angiographic success (47% vs. 72%; p = .003) and 30 day amputation free survival (53% vs. 82%; p < .001) were lower for cases with major bleeding. Older age (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.02 - 1.11), cardiac history (OR 3.35, 95% CI 1.39 - 8.06), high dose regimens (≥ 75 000 IU/hour urokinase; OR 2.67, 95% CI 1.18 - 6.04), and fibrinogen values < 1.0 g/L (OR 5.59, 95% CI 1.98 - 15.77) were independent predictors for major bleeding during CDT.

CONCLUSION

High dose thrombolytic regimens and fibrinogen levels of ≤ 1.0 g/L are associated with more major bleeding during thrombolytic therapy. Major bleeding significantly worsened the clinical outcome. A prospective comparative study is needed to assess the benefit of monitoring fibrinogen levels.

A Brief Review of Thrombolytics for Venous Interventions

Anticoagulation continues to be the mainstay of therapy for the management of venous thromboembolism. However, anticoagulation does not lead to the breakdown or dissolving of the thrombus. In an acute pulmonary embolism, extensive thrombus burden can be associated with a high risk for early decompensation, and in acute deep venous thrombosis, it can be associated with an increased risk for phlegmasia. In addition, residual thrombosis can be associated with chronic thromboembolic pulmonary hypertension and postthrombotic syndrome in a chronic setting. Thrombolytic therapy is a crucial therapeutic choice in treating venous thromboembolism for thrombus resolution. Historically, it was administered systemically and was associated with high bleeding rates, particularly major bleeding, including intracranial bleeding. In the last two decades, there has been a significant increase in catheter-based therapies with and without ultrasound, where lower doses of thrombolytic agents are utilized, potentially reducing the risk for major bleeding events and improving the odds of reducing the thrombus burden. In this article, we provide an overview of several thrombolytic therapies, including delivery methods, doses, and outcomes.

Comparative study on the efficacy and safety of alteplase and urokinase in the treatment of acute cerebral infarction

BACKGROUND

Acute cerebral infarction (ACI) is a common cerebrovascular disease in clinical practice.

OBJECTIVE

The present study aims to investigate the efficacy and safety of alteplase and urokinase in treating ACI.

METHODS

A total of 96 patients with ACI, who were treated with alteplase and urokinase, were selected as the main subjects. Among these patients, 45 patients with ultra-early acute cerebral infarction, who received intravenous thrombolysis with RT-PA (alteplase), were included in the treatment group, while 51 patients with acute cerebral infarction, who were treated with urokinase in the same time period, were included in the control group.

RESULTS

The National Institute of Health Stroke Scale (NIHSS) scores were significantly lower in the treatment group and control group (P< 0.05) at two hours, seven days and 14 days after thrombolysis, when compared to those before thrombolysis. The bleeding rate was significantly lower in the control group, when compared to the treatment group (P< 0.05).

CONCLUSION

The intravenous thrombolysis with urokinase or alteplase in the ultra-early stage of acute cerebral infarction can reduce the neurological injury symptoms and effectively improve the prognosis of patients with stroke. Urokinase is lower in risk of bleeding, but better in safety, when compared to alteplase.

Accelerated treatment with rtPA for pulmonary embolism induced circulatory arrest

Patients with circulatory arrest due to pulmonary embolism (PE) should be treated with fibrinolytics. Current guidelines do not specify which regimen to apply, and it has been suggested that the regimen of 100 mg rtPA/2 h should be used, because this is recommended for hemodynamic instable PE in the ESC/ERS Guideline. This two hour regimen, however, is incompatible with key principles of cardiopulmonary resuscitation (CPR), such as employment of interventions that allow fast evaluation of effectiveness, and limitation of the total duration of CPR to avoid poor neurological outcomes. Additionally, the low flow-state during CPR has important consequences for the pharmacokinetic properties of rtPA. Arguably, the volume of distribution is lower, the metabolism reduced and the half life time longer. Therefore, these changes largely discard the rationale to use high dosages of rtPA over a prolonged period of time. More importantly, these changes highlight that the guideline recommendations, based on studies in patients without circulatory arrest, cannot be easily translated to the situation of circulatory arrest. An accelerated regimen of rtPA (0.6 mg/kg/15 min., max 50 mg) is mentioned by the 2019 ESC/ERS Guideline. However, empirical support or a rationale is not provided. Due to the rarity of the situation and ethical difficulties associated with randomizing unconscious patients, a randomized head-to-head comparison between the two regimens is unlikely to ever be performed. With this comprehensive overview of the pharmacokinetics of rtPA and current literature, a strong rationale is provided that the accelerated protocol is the regimen of choice for patients with PE-induced circulatory arrest.

Management of early hepatic artery thrombosis following living-donor liver transplantation: feasibility, efficacy and potential risks of endovascular therapy in the first 48 hours post-transplant-a retrospective cohort study

This retrospective cohort study aims to review our 18-year experience with early hepatic artery thrombosis (e-HAT) following living-donor liver transplantation (LDLT), as well as to assess the feasibility, efficacy and potential risks of endovascular management of e-HAT in the first 48 hours (hrs) post-LDLT. Medical records of 730 patients who underwent LDLT were retrospectively reviewed. In all cases who had developed e-HAT, treatment modalities employed and their outcomes were evaluated. Thirty-one patients developed e-HAT(4.2%). Definite technical success and 1-year survival rates of surgical revascularization[11/31 cases(35.5%)] were 72.7% & 72.7%, whereas those of endovascular therapy[27/31 cases(87.1%)] were 70.4% & 59.3%, respectively. Endovascular therapy was carried out in the first 48hrs post-transplant in 9/31 cases(29%) [definite technical success:88.9%, 1-year survival:55.6%]. Four procedure-related complications were reported in 3 of those 9 cases(33.3%). In conclusion, post-LDLT e-HAT can be treated by surgical revascularization or endovascular therapy, with comparable results. Endovascular management of e-HAT in the first 48hrs post-LDLT appears to be feasible and effective, but is associated with a relatively higher risk of procedure-related complications, compared to surgical revascularization. Hence, it can be reserved as a second-line therapeutic option in certain situations where surgical revascularization is considered futile, potentially too complex, or potentially more risky.

Catheter-directed intra-arterial thrombolysis for lower extremity arterial occlusions

Catheter-directed intra-arterial thrombolysis (CDT) is a rational treatment method in patients with acute/subacute and even some chronic occlusions of lower extremity arteries and bypass grafts having salvageable limb ischemia. Immediate vessel patency can be achieved with an acceptable complication rate in many patients, especially those with fresh thrombus or emboli. It can be also an adjuvant treatment modality for endovascular interventions for chronic occlusions. There is no standard method of CDT including thrombolytic agent dose and technique. Selection of treatment strategy should be based on individual judgment based on viability of limb, lesion characteristics, and risks of hemorrhage.

Comparison of alteplase and urokinase for pharmacomechanical thrombolysis of clotted hemodialysis access

BACKGROUND

Percutaneous pharmacomechanical thrombolysis is increasingly used to salvage thrombosed hemodialysis access. We aim to evaluate the effectiveness of alteplase compared to urokinase in percutaneous pharmacomechanical thrombolysis clotted access.

METHODS

Records of patients who underwent pharmacomechanical thrombolysis at Interventional Nephrology Suite in a tertiary teaching hospital from 1 January 2016 to 31 December 2016 were reviewed. Technical and clinical success rates, thrombosis-free and cumulative survivals, procedure time, and radiation dose imparted to patients were compared for pharmacomechanical thrombolysis with urokinase versus alteplase.

RESULTS

A total of 122 incident patients underwent pharmacothrombolysis (n = 53 for urokinase, n = 69 for alteplase) during the study period. The mean dose of urokinase and alteplase used was 176,897 ± 73,418 units and 3.7 ± 0.8 mg, respectively. Pharmacomechnical thrombolysis using urokinase versus alteplase has similar technical success rate (98.1% vs 97.1%, p = 0.599), clinical success rate (88.7% vs 97.1%, p = 0.068), complication rate (9.4% vs 13.0%, p = 0.373), and primary patency rates at 3 months (57.1% vs 70.1%, p = 0.106). Thrombosis-free survivals of the vascular access were 113.2 (35.3, 196) days versus 122 (84, 239) days (p = 0.168). Cumulative survivals were 239 (116, 320) vs 213 (110.5, 316.5) days (p = 0.801). Procedure time, fluoroscopy time, skin dose, and dose were significantly lower for pharmacomechanical thrombolysis using alteplase compared to urokinase (p = 0.045, p < 0.0001, p = 0.006, p = 0.001, respectively). Stenting was found to be associated with successful dialysis following thrombolysis on univariate analysis (odds ratio: 9.167, 95% confidence interval: 1.391-19.846, p = 0.021), although this was no longer significant in multivariate analysis (p = 0.078).

CONCLUSION

Alteplase is an effective and safe alternative to urokinase for pharmacomechanical thrombolysis of clotted vascular access.

Circulatory collapse, right ventricular dilatation, and alveolar dead space: A triad for the rapid diagnosis of massive pulmonary embolism

A triad of circulatory collapse, right ventricular dilatation, and large alveolar dead space is proposed for the rapid diagnosis and treatment of massive pulmonary embolism. A 17year-old female on oral contraceptives collapsed at home becoming incoherent with shallow breathing. Paramedics initiated mechanical chest compression and transported the patient to our emergency department, arriving minimally responsive with undetectable blood pressure but having positive corneal reflexes and bradycardia with wide QRS. The trachea was intubated and goal-directed echocardiography revealed marked right ventricular dilatation with septal flattening. The arterial PCO₂ was 40mmHg with an end-tidal PCO₂ of 8mmHg, revealing a large alveolar dead space. Persistent hypotension, bradycardia, and fading alertness despite epinephrine and norepinephrine infusions prompted resumption of chest compression. Intravenous alteplase (10mg bolus over 10min followed by 90mg over 110min) begun 125min after collapse improved hemodynamic function within 10min allowing discontinuation of chest compression. Five and a half hours after starting alteplase, the patient was hemodynamically stable and had normal end-tidal PCO₂. A CT-angiogram showed the pulmonary arteries free of emboli but a thrombus in the right common iliac vein. The patient recovered fully and was discharged home on warfarin 8days later. Based on this and other reports, we propose a triad of circulatory collapse, right ventricular dilatation, and large alveolar dead space for the rapid diagnosis and treatment of massive pulmonary embolism, with systemic fibrinolysis as the first-line intervention.

Should catheter-directed thrombolysis be monitored?

Catheter-directed thrombolysis for deep venous thrombosis is considered the basic treatment modality for intrathrombus removal. This method is preferably used in patients with iliofemoral deep venous thrombosis due to poor spontaneous recanalization in this segment, especially on the left side. The method was published almost 25 years ago and has gained ground in the treatment because of poor results from systemic thrombolysis and because of the possibility of stenting any underlying iliac obstruction during the procedure. However, the publications of catheter-directed thrombolysis reveal a great heterogeneity concerning catheter-directed thrombolysis technique and the lack of high quality evidence about monitoring as a tool to minimize the risk of bleeding and pulmonary embolism. Strict inclusion and exclusion criteria, correct composition and infusion of thrombolysis agent, imaging thrombus clearance during catheter-directed thrombolysis, ensuring flow enhancement during the bedridden situation, careful evaluation of indication for stenting based on imaging, and sufficient conversion to anticoagulation treatment following catheter-directed thrombolysis are essential. The aim of this paper is to discuss different treatment aspects of catheter-directed thrombolysis for iliofemoral thrombosis and to suggest a monitoring model for future treatment.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Antihypertensives

OBJECTIVE

Hypertension remains a common condition in pediatric cardiac intensive care. The physiologic effects of hypertension in this population are complex and are impacted by patient age, comorbidities, and primary cardiac disease. The objective of this study is to review current pharmacotherapies for the management of systemic hypertension in the pediatric cardiac ICU.

DATA SOURCES

Relevant literature to the treatment of systemic hypertension in children was included. Specific focus was given to literature studying the use of therapies in critically ill children and those with heart disease. Reference textbooks and drug packaging inserts were used for drug-specific pediatric guidelines.

STUDY SELECTION

A search of MEDLINE, PubMed, and the Cochrane Database was performed to find literature about the management of hypertension in children. Metaanalyses and pediatric-specific studies were primarily considered and cross-referenced. Pertinent adult studies were included.

DATA EXTRACTION

Once the studies for inclusion were finalized, priority for data extraction was given to pediatric-specific studies that focused on children with heart disease and critical illness.

CONCLUSIONS

Systemic hypertension is common, and there is significant heterogeneity in the patient population with critical heart disease. There are limited large, prospective analyses of safety and efficacy for pediatric drug antihypertensive agents. Despite patient heterogeneity, most pharmacotherapies are safe and efficacious.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Anticoagulation and Thrombolysis

OBJECTIVE

Thrombotic complications are increasingly being recognized as a significant cause of morbidity and mortality in pediatric and congenital heart disease. The objective of this article is to review the medications currently available to prevent and treat such complications.

DATA SOURCES

Online searches were conducted using PubMed.

STUDY SELECTION

Studies were selected for inclusion based on their scientific merit and applicability to the pediatric cardiac population.

DATA EXTRACTION

Pertinent information from each selected study or scientific review was extracted for inclusion.

DATA SYNTHESIS

Four classes of medications were identified as potentially beneficial in this patient group: anticoagulants, antiplatelet agents, thrombolytic agents, and novel oral anticoagulants. Data on each class of medication were synthesized into the follow sections: mechanism of action, pharmacokinetics, dosing, monitoring, reversal, considerations for use, and evidence to support.

CONCLUSIONS

Anticoagulants, antiplatelet agents, and thrombolytic agents are routinely used successfully in the pediatric patient with heart disease for the prevention and treatment of a wide range of thrombotic complications. Although the novel oral anticoagulants have been approved for a limited number of indications in adults, studies on the safety and efficacy of these agents in children are pending.

Use of argatroban and catheter-directed thrombolysis with alteplase in an oncology patient with heparin-induced thrombocytopenia with thrombosis

PURPOSE

The case of an oncology patient who developed heparin-induced thrombocytopenia with thrombosis (HITT) and was treated with argatroban plus catheter-directed thrombolysis (CDT) with alteplase is presented.

SUMMARY

A 63-year-old Caucasian man with renal amyloidosis undergoing peripheral blood stem cell collection for an autologous stem cell transplant developed extensive bilateral upper-extremity deep venous thrombosis (DVT) and pulmonary embolism secondary to heparin-induced thrombocytopenia. A continuous i.v. infusion of argatroban was initiated, and the patient was managed on the general medical floor. After one week of therapy, he was transferred to the intensive care unit with cardiopulmonary compromise related to superior vena cava (SVC) syndrome. A percutaneous mechanical thrombectomy and CDT with alteplase were attempted, but the procedure was aborted due to epistaxis. The epistaxis resolved the next day, and the patient was restarted on argatroban. A second percutaneous mechanical thrombectomy was performed six days later and resulted in partial revascularization of the SVC and central veins. Postthrombectomy continuous CDT with alteplase was commenced while argatroban was withheld, and complete patency of the SVC and central veins was achieved after three days of therapy. Alteplase was discontinued, and the patient was reinitiated on argatroban; ultimately, he was transitioned to warfarin for long-term anticoagulation. Although the patient recovered, he experienced permanent vision and hearing loss, as well as end-stage renal disease.

CONCLUSION

A 63-year-old man with renal amyloidosis and SVC syndrome secondary to HITT was successfully treated with argatroban and CDT with alteplase.

Interventional radiological treatment of perihepatic vascular stenosis or occlusion in pediatric patients after liver transplantation

PURPOSE

Evaluation of the efficacy and safety of percutaneous treatment of vascular stenoses and occlusions in pediatric liver transplant recipients.

METHODS

Fifteen children (mean age 8.3 years) underwent interventional procedures for 18 vascular complications after liver transplantation. Patients had stenoses or occlusions of portal veins (n = 8), hepatic veins (n = 3), inferior vena cava (IVC; n = 2) or hepatic arteries (n = 5). Technical and clinical success rates were evaluated.

RESULTS

Stent angioplasty was performed in seven cases (portal vein, hepatic artery and IVC), and sole balloon angioplasty was performed in eight cases. One child underwent thrombolysis (hepatic artery). Clinical and technical success was achieved in 14 of 18 cases of vascular stenoses or occlusions (mean follow-up 710 days).

CONCLUSION

Pediatric interventional radiology allows effective and safe treatment of vascular stenoses after pediatric liver transplantation (PLT). Individualized treatment with special concepts for each pediatric patient is necessary. The variety, the characteristics, and the individuality of interventional management of all kinds of possible vascular stenoses or occlusions after PLT are shown.

Review of pharmacology and physiology in thrombolysis interventions

Reperfusion therapy using thrombolytic agents has been shown to be a safe and effective treatment strategy for arterial ischemia, venous thrombosis, massive pulmonary embolism, and acute stroke. Thrombolytic agents have evolved over the course of a few decades, from nonfibrin selective to fibrin-selective agents. The development and modification of these agents have resulted in improved understanding of their pharmacologic attributes, and their effects on the complex molecular events that occur during thrombolysis goal-directed therapies. The current review focuses on the physiology and pharmacology of the thrombolytic agents that have been or are currently in use for interventional thrombolysis interventions. Attention is also given to the particular role that thrombolytic agents play in the current management of peripheral vascular disease and acute stroke.

Endovascular management of early hepatic artery thrombosis after living donor liver transplantation

To study the feasibility of endovascular management of early hepatic artery thrombosis (HAT) after living-donor liver transplantation (LDLT) and to clarify its role as a less invasive alternative to open surgery. A retrospective review of 360 recipients who underwent LDLT. Early HAT developed in 13 cases (3.6%). Diagnosis was performed using Doppler, CT angiography, and digital subtraction angiography. Intra-arterial thrombolysis (IAT) was performed using streptokinase or tPA. In case of underlying stricture, PTA was attempted. If the artery did not recanalize, continuous infusion was performed and monitored using Doppler US. Initial surgical revascularization was successful in 2/13 cases. IAT was performed in 11/13 cases. The initial success rate was 81.8% (9/11), the failure rate was 18.2% (2/11). Rebound thrombosis developed in 33.3% (3/9). Hemorrhage developed after IAT in 2/11 cases (18.2%). Definite endovascular treatment of HAT was achieved in 6/11 cases (54.5%) and definite treatment (surgical, endovascular or combined) in 9/13 cases (69%). (Follow-up 4 months-4 years). Endovascular management of early HAT after LDLT is a feasible and reliable alternative to open surgery. It plays a role as a less invasive approach with definite endovascular treatment rate of 54.5%.

Quality improvement guidelines for percutaneous catheter-directed intra-arterial thrombolysis and mechanical thrombectomy for acute lower-limb ischemia

Percutaneous catheter-directed intra-arterial thrombolysis is a safe and effective method of treating acute and subacute lower limb ischemia, as long as accurate patient selection and procedural monitoring are ensured. Although larger, controlled trials are needed to establish the role of PTDs in ALI, mechanical thrombectomy could currently be applied combined with lytic infusion in selected cases where rapid recanalization is required or as a stand-alone therapy when the administration of thrombolytic agents is contraindicated.

Acute limb ischemia

Acute limb ischemia is a medical emergency with management options ranging from urgent revascularization to limb amputation. The best patient outcome requires tailoring the treatment to the individual patient. This article describes a step-by-step approach for diagnosis and management of patients presenting with acute limb ischemia.

Percutaneous options for acute deep vein thrombosis

Anticoagulant therapy is associated with poor late limb outcomes in many patients with deep vein thrombosis (DVT). Because systemic thrombolysis and surgical thrombectomy have inherent limitations, image-guided percutaneous thrombus removal is currently favored. Pharmacologic thrombolysis is effective in removing thrombus, but long-term benefit has not been conclusively demonstrated and major bleeding rates appear to be higher than those observed with anticoagulation alone. Percutaneous mechanical thrombectomy is limited as a stand-alone DVT treatment method by inability to clear large thrombosed veins completely and by pulmonary embolism. Pharmacomechanical thrombolysis represents the most promising currently available method to treat DVT. Randomized trials with long-term follow-up are needed to determine the appropriate indications for these procedures. In the meantime, a highly individualized approach to selection of patients is recommended, taking into account the chronicity and anatomic extent of DVT, the presence of circulatory compromise, the patient's bleeding risk profile, life expectancy, and anticipated activity level.

Differentiating pharmacologic agents used in catheter-directed thrombolysis

The use of catheter-directed thrombolysis is a proven treatment for arterial ischemia, deep vein thrombosis, and severe pulmonary embolism. For arterial ischemia, thrombolysis has resulted in improved amputation-free survival and fewer subsequent surgeries to reestablish blood flow to the ischemic limb. The management of patients with thromboembolic diseases is complex, and the multiple thrombolytic drugs available to choose from compound this complexity. Although some believe the available thrombolytic agents are interchangeable, real biochemical differences exist that may prove otherwise. This article describes these pharmacologic differences and how they may affect the clinical practice of catheter-directed thrombolysis.

Low-dose, once-daily, intraclot injections of alteplase for treatment of acute deep venous thrombosis

PURPOSE

To evaluate the safety and efficacy of once-daily intraclot injections of low doses (≤ 10 mg) of tissue plasminogen activator (tPA) for thrombolysis of venous thrombosis.

MATERIALS AND METHODS

In prospective studies, 33 patients with subclavian, jugular, and central venous thrombosis (SJ-CVT) (all but two cases associated with central catheters) were treated once a day with ≤ 4 mg/day of tPA, and 30 patients with acute deep vein thrombosis of the lower extremity (DVT-LE) < 14 days old were treated once a day with ≤ 10 mg/leg/day of tPA by intraclot "lacing" of thrombus without continuous infusions of tPA.

RESULTS

Patency was restored in 26 (79%) of 33 patients with SJ-CVT using an average total dose of 7.1 mg of tPA/per patient and average of 2.1 treatments or days of therapy. Five patients received thrombolytic therapy for SJ-CVT as outpatients. Initial patency was restored in 29 (97%) of 30 patients with acute DVT-LE using an average total dose of 20 mg of tPA per patient over an average of 2.7 treatments/or days per patient. Follow-up imaging examinations at 6 months showed continued patency in 27 (96%)/of 28 patients. There were no major bleeding complications, and no patient required a blood transfusion.

CONCLUSIONS

Intraclot injection of low doses of alteplase is effective for acute venous thrombosis, and pharmacokinetic data suggest potentially greater safety.

Peripherally inserted central catheters

Peripherally inserted central catheters are increasingly used in the pediatric and adolescent population for long-term central access. This article reviews the indications, insertion techniques, and complications of peripherally inserted central catheter lines.

Successful thrombolytic therapy with recombinant tissue-type plasminogen activator for massive pulmonary embolism -A case report-

Massive pulmonary embolism is associated with significant perioperative morbidity and mortality. We report here on a case of a 69-year-old man who suffered a massive pulmonary embolism with pulseless electrical activity during knee arthroscopic surgery. After a diagnosis was made by performing transthoracic echocardiography, the patient was treated with recombinant tissue-type plasminogen activator. The patient was transferred to the intensive care unit after his hemodynamic status improved. The patient went on to make a full cardiopulmonary recovery without any complications.

Endovascular thrombolysis using monteplase for non-chronic deep venous thrombosis

This study was designed to evaluate the usefulness of endovascular thrombolysis using monteplase for deep venous thrombosis (DVT). Between December 2005 and October 2009, at our institution nine endovascular thrombolysis treatments with monteplase were performed for symptomatic DVT in eight patients (6 women, 2 men; mean age, 56 (range, 15-80) years). In all, systemic anticoagulation administered by the peripheral intravenous route with heparin and/or thrombolysis with urokinase followed by anticoagulation with orally administered warfarin had been performed, and subsequently six endovascular treatments without monteplase were administered. However, DVT persisted, and endovascular treatments with monteplase were tried. In six (67%) of the nine procedures, DVT completely or almost completely disappeared after endovascular thrombolysis with monteplase. Mean dose of monteplase used was 2,170,000 IU. There was only one procedure-related complication. In one patient, just after thrombolysis with monteplase, bleeding at the puncture site and gingival bleeding occurred. Bleeding was stopped by manual astriction only. Endovascular thrombolysis with monteplase may be an effective treatment for DVT, even in cases resistant to traditional systemic anticoagulation and thrombolysis and endovascular procedures without monteplase.

Continuous Intraarterial Thrombolysis for Early Hepatic Artery Thrombosis Following Liver Transplantation: Case Report

Hepatic Artery thrombosis remains one of the major causes of graft failure and mortality in liver transplant recipients. Urgent re-transplantation has been considered as mainstay therapy; however, even with re-transplantation mortality of more than 50% has been reported by many series. Early detection on Doppler ultrasonography and subsequent revascularization in asymptomatic patients can avoid graft loss. Endovascular therapy including intra-arterial thrombolysis, percutaneous transluminal angioplasty, and stent placement have shown encouraging results in recent years; nevertheless, their use remains controversial due to potential risk of bleeding. We present a case of early hepatic artery thrombosis following liver transplantation treated successfully with continuous transcatheter intra-arterial thrombolysis using tissue plasminogen activator (t-PA).

Endovascular treatment of hepatic artery thrombosis following liver transplantation

Hepatic artery thrombosis (HAT) is the most frequent vascular complication following orthotopic liver transplantation. Urgent retransplantation has been considered as the mainstay therapy. Surgical revascularization is an effective alternative in asymptomatic patients. Endovascular therapies including intra-arterial thrombolysis, percutaneous transluminal angioplasty (PTA), and stent placement have shown encouraging results in recent years; however, their use remains controversial because of potential risk of hemorrhage. Until June 2009, 69 cases were published in 16 reports describing therapeutic potential of endovascular modalities. Interventions were performed as early as within 4 h to as late as 120 days in patients ranging from 4 months to 64 years of age. Majority of published reports suggested the use of urokinase. Thrombolysis was successful in 47 out of 69 (68%) patients. Bleeding was the most common complication including fatal intra-abdominal hemorrhage in three patients. Twenty-nine out of 47 (62%) patients underwent further intervention in the form of PTA, stenting, or both. The follow-up patency ranged from 1 month to 26 months. In conclusion, whenever possible, efforts should be made to rescue the liver grafts through urgent revascularization (surgical and/or endovascular) depending on patient's condition and interventional expertise at the transplant center; reserving the option of retransplantation for failure, complications, and cases with severe clinical symptoms or allograft dysfunction.

Efficacy of intrapleural tissue-type plasminogen activator in the treatment of loculated parapneumonic effusions

PURPOSE

To assess the feasibility and effectiveness of intrapleural recombinant tissue-type plasminogen activator (r-tPA) in the treatment of loculated parapneumonic effusions (PPEs).

MATERIALS AND METHODS

A single-arm prospective study of 25 consecutive patients with loculated PPEs was analyzed. All patients received 6-mg doses of intrapleural r-tPA on a defined schedule via a thoracostomy tube. The volume of output from the tubes was recorded and analysis of the fluid composition performed. Follow-up was both clinical and radiographic, with all patients undergoing pre- and postprocedural computed tomography.

RESULTS

Eighteen of the 25 patients (72%) required no additional intervention and had a complete clinical and radiographic response with the fibrinolytic therapy. Seven patients (28%) were treated with video-assisted thoracoscopic surgery, but no patient required thoracotomy for total decortication. There were no hemorrhagic complications.

CONCLUSIONS

Intrapleural r-tPA is effective in the treatment of loculated PPEs. It can be performed safely and in some patients may avoid the need for additional surgical intervention.

Catheter-directed thrombolysis with the Endowave system in the treatment of acute massive pulmonary embolism: a retrospective multicenter case series

PURPOSE

To evaluate the efficacy of thrombolysis with the EndoWave peripheral infusion system in the treatment of patients with massive pulmonary embolism (PE) as compared to patients treated with catheter-directed thrombolysis.

MATERIALS AND METHODS

Ten patients (five men and five women; age range, 31-85 years; mean age, 54.20 years) with massive acute PE (17 lesions) were treated with ultrasonography (US)-assisted catheter-directed thrombolysis with the Endowave system. All patients had hypoxia and dyspnea. No patient had contraindication for thrombolysis. Angiographic findings, duration of lysis, dose of thrombolytics used, and procedural complications were recorded. Thrombolytics used were urokinase, tissue-type plasminogen activator (tPA), and Reteplase.

RESULTS

Complete thrombus removal was achieved in 13 of the 17 lesions (76%), near complete thrombolysis was achieved in three lesions (18%), and partial thrombolysis was achieved in one lesion (6%). The mean time of thrombolysis was 24.76 hours +/- 8.44 (median, 24 hours). The mean dose of tPA used for the Endowave group was 0.88 mg/h +/- 0.19 (13 lesions).

CONCLUSIONS

US-assisted catheter-directed thrombolysis is an effective method for treating massive thrombolysis. It has the potential to shorten the time of lysis and lower the dose of thrombolytics.

Catheter-directed thrombolysis for acute limb ischemia

Acute limb ischemia is a potentially life-threatening clinical event. Thrombosis in situ, bypass graft thrombosis, and embolic occlusion are the three major precipitating events leading to acute limb ischemia. Management of acute ischemia depends on the clinical status of the affected limb and patient comorbidities. Catheter-directed thrombolysis (CDT) is the treatment of choice for patients with relatively mild acute limb ischemia (Rutherford categories I and IIa) with no contraindications to thrombolytic therapy. Patients with severe acute limb ischemia (Rutherford category IIb) need emergent revascularization. CDT should be considered, nonetheless, if the relative risks compared with primary operation are favorable. CDT is a life- and limb-saving treatment for many patients despite limitations of efficacy and associated complications. This article is a review of the etiology of acute arterial occlusion; clinical triage of patients presenting with acute limb ischemia; catheter guide wire techniques, pharmacological agents, and devices in current use for CDT; as well as the outcomes of CDT.

Peripheral Arteries: Treatment with Antibodies of Platelet Receptors and Reteplase for Thrombolysis—APART Trial

PURPOSE

To prospectively compare the safety and efficacy of combination therapy with the glycoprotein IIb/IIIa antagonist abciximab plus the third-generation thrombolytic agent reteplase versus those of therapy with the standard thrombolytic agent urokinase plus abciximab.

MATERIALS AND METHODS

The study was approved by the local ethics committee, and patient informed consent was obtained. Patients with peripheral arterial occlusions less than 60 days old (n=120) were enrolled in the study: 50 patients (32 men, 18 women; mean age, 67 years; range, 23-88 years) received reteplase plus abciximab and 70 patients (36 men, 34 women; mean age, 68 years; range, 28-88 years) received urokinase plus abciximab. Study end points were the rate of major complications at 30 days, therapeutic success, and survival without open surgery or major amputation at follow-up. Fisher exact test was used to compare treatment groups with respect to dichotomous variables, and the event-free-survival probabilities were calculated with the Kaplan-Meier method. For the comparison of the lengths of occlusions among the groups, a two-sample t test was used.

RESULTS

Therapeutic success (P=.7) did not differ between the groups, whereas the time required for thrombolysis was lower in the urokinase-plus-abciximab group (P=.001). Patients who received reteplase plus abciximab tended to develop more minor complications (mainly bleeding events) (P<.001). During long-term follow-up (2-4 years), no group differences were observed. The reocclusion rate was 48% (22 of 46) in the reteplase-plus-abciximab group and 45% (29 of 64) in the urokinase-plus-abciximab group. Only two of 120 major amputations were counted in the follow-up period.

CONCLUSION

The proposed regimen resulted in only a limited number of major complications, and the low amputation rate in both groups may be attributed to abciximab.

Successful intraoperative use of recombinant tissue plasminogen activator during liver transplantation complicated by massive intracardiac/pulmonary thrombosis

During orthotopic liver transplantation a patient received epsilon-aminocaproic acid and clotting factors. Shortly after hepatic artery clamping the patient developed a massive intracardiac/intravascular thrombosis that resulted in cardiac arrest. After diagnosis by transesophageal echocardiography, the patient was treated with recombinant tissue plasminogen activator through a central venous catheter advanced into the right atrium. After treatment with recombinant tissue plasminogen activator, the patient's hemodynamic status improved, permitting the liver transplant to be completed. The patient was ultimately discharged to home. We report the successful intraoperative resuscitation of a patient with acute intracardiac/intravascular thrombosis during an orthotopic liver transplantation using thrombolytic therapy.

Comparative Safety and Efficacy of Urokinase and Recombinant Tissue Plasminogen Activator for Peripheral Arterial Occlusion: A Meta-Analysis

STUDY OBJECTIVE

To evaluate differences in the efficacy and safety of recombinant tissue plasminogen activator (rt-PA) and urokinase in the treatment of peripheral arterial occlusion.

DESIGN

Systematic review and meta-analysis of prospective comparative trials.

DATA SOURCE

PubMed/MEDLINE database from 1966-October 2004.

MEASUREMENTS AND MAIN RESULTS

The literature was systematically searched to identify prospective comparative trials of urokinase and rt-PA for the treatment of peripheral arterial occlusion. The primary outcome measure was successful complete lysis of the occlusion. Other outcome measures were hemorrhage (major, minor, or combined), intracranial hemorrhage, limb loss, and mortality. Six trials were identified, five of which were randomized. On meta-analysis, the rate of clot lysis was higher with rt-PA than with urokinase (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.12-2.10, p=0.007). However, urokinase was associated with lower rates of minor (OR 0.52, 95% CI 0.28-0.97, p=0.04) and total (OR 0.51, 95% CI 0.29-0.91, p=0.02) bleeding. Rates of major hemorrhage, intracranial hemorrhage, limb loss, and mortality were similar between agents.

CONCLUSION

Urokinase was less effective than rt-PA in successfully lysing acute peripheral arterial occlusion, but it was associated with lower rates of total and minor bleeding. Overall, rt-PA was a reasonable substitute for urokinase, now that urokinase has been removed from the market in the United States. However, judicious monitoring for minor bleeding is necessary.

Usefulness of catheter-directed thrombolysis using alteplase in peripheral vascular occlusion

This study evaluated the safety and efficacy of alteplase in catheter-directed treatment for peripheral arterial and venous thrombosis and considered the optimal dosing regimen. Forty-four patients (49 encounters) underwent transcatheter therapy using alteplase between January and November 1999. The most common indications for thrombolysis were peripheral arterial occlusion (PAO) and venous thrombosis (38 patients, 43 encounters). Each encounter was reviewed for indication, dosage of alteplase, duration of infusion, concomitant use of anticoagulation, degree of lysis, and complications. Patients were divided into low-dose (0.5 to 1.0 mg/hr), mid-dose (1.0 to 1.5 mg/hr), and high-dose (>1.5 mg/hr) groups. For PAO, there was no significant difference in the success rate between the 3 dose groups. A lower complication rate was achieved in the low-dose group. For venous thrombosis, there was no difference in the overall success or complication rates for each of the 3 groups. Partial lysis was achieved more readily in the mid and high-dose groups, but the risk of serious complications was greater. Overall, the complete thrombolysis rate was 71% for PAO and 55% for venous thrombosis. Major and minor complication rates were 7% and 19%, respectively. An equivalent success rate with a lower complication rate can be achieved using a low-dose constant catheter-directed infusion of alteplase for cases of PAO. Cases of venous thrombosis had a lower overall success rate compared with PAO. A mid-dose infusion of alteplase can achieve greater complete and partial thrombolysis rates without increasing the complication rate. Major and minor complication rates were similar to the rates given in the published literature.

Short and long alteplase dwells in dysfunctional hemodialysis catheters

BACKGROUND

Hemodialysis catheter dysfunction (CD) is the inability to attain adequate blood pump speeds (BPS) and is attributed to thrombus or catheter malposition; alteplase (TPA) is often given in a variety of dwell times to treat CD. The purpose of this study was to determine if TPA dwell time affects short- or long-term catheter patency rates.

METHODS

Sixty hemodialysis (HD) patients with CD, as defined by BPS of < 250 mL/min, were randomized to receive either 1- or > 48-hr (to subsequent HD run) TPA dwell. The primary outcomes were catheter patency (BPS of > 250 mL/min) at the subsequent HD run and catheter patency at 2 weeks. The secondary outcome was the time from study entry to the next catheter intervention (including subsequent TPA installation).

RESULTS

After TPA installation, a 78% overall catheter patency rate was observed at the subsequent HD run, falling to 48% patency at 2 weeks. There is no statistically significant difference between the short and long TPA dwell groups for catheter patency at the subsequent HD run (76.9% vs. 79.4%) or at 2 weeks (42.3% vs. 52.9%). Multivariate analysis demonstrates that the use of TPA on two or more previous occasions is a predictor of TPA failure both at the subsequent HD run and at 2 weeks. TPA installation achieves a median catheter function time of only 14 days, after which CD reoccurs.

CONCLUSION

This study demonstrates that although patency for the next HD run can be achieved with either short or long TPA dwell, neither is reliable in terms of long-term patency. Strategies that employ TPA for CD are temporary and allow a 2-week window during which more definitive therapies for HD access should be sought.

Pharmacomechanical Thrombolysis and Early Stent Placement for Iliofemoral Deep Vein Thrombosis

PURPOSE

To evaluate an approach to the treatment of iliofemoral deep vein thrombosis (DVT) that included pharmacomechanical catheter-directed thrombolysis with reteplase and the Helix mechanical thrombectomy device, followed by early stent placement.

MATERIALS AND METHODS

During 3-year period, 23 symptomatic limbs in 18 patients with iliofemoral DVT were treated with reteplase catheter-directed thrombolysis. After an initial infusion of 8 to 16 hours, any residual acute thrombus over a long segment (> 10 cm) was treated by maceration with use of the Helix thrombectomy device. Residual short-segment (< 10 cm) iliac vein thrombus and/or stenosis were treated with stent placement. Technical success, clinical success, complications, thrombolytic infusion time, total thrombolytic agent dose, fibrinogen level changes, and late limb status were retrospectively analyzed.

RESULTS

Technical success was achieved in 23 of 23 limbs (100%). Clinical success was achieved in 22 of 23 limbs (96%). Complete or partial thrombolysis was observed in 19 of 23 limbs (83%). Major bleeding was observed in one patient (6%) and necessitated blood transfusion. Mean per-limb thrombolytic infusion time and total dose were 19.6 hours +/- 8.1 and 13.8 U +/- 5.3 reteplase, respectively. Mean serum fibrinogen nadir and percentage drop in serum fibrinogen were 282 mg/dL +/- 167 and 47% +/- 24%, respectively. Late (mean, 19.8 +/- 11.6 months) modified Venous Disability Scores were 0 (none) for six limbs, 1 (mild) for 10 limbs, 2 (moderate) for two limbs, and 3 (severe) for no limbs.

CONCLUSION

In a preliminary experience, pharmacomechanical catheter-directed iliofemoral DVT thrombolysis with early stent placement was safe and effective.

Comparison of Urokinase, Alteplase, and Reteplase for Catheter-directed Thrombolysis of Deep Venous Thrombosis

PURPOSE

To compare the efficacy, safety, and costs associated with catheter-directed thrombolysis with urokinase (UK) and the recombinant agents alteplase (tissue plasminogen activator [TPA]) and reteplase (recombinant plasminogen activator [RPA]) in the treatment of symptomatic deep vein thrombosis (DVT).

MATERIALS AND METHODS

The authors conducted a retrospective analysis on 74 patients (82 limbs) who underwent treatment for DVT. Thrombosed extremities were treated with either urokinase with therapeutic heparin dosing (UK group; 38 limbs), alteplase with subtherapeutic heparin dosing (TPA group; 32 limbs), or reteplase with subtherapeutic heparin dosing (RPA group; 12 limbs). Infusion times, dosages, drug costs, success rates, and complications were compared among the groups.

RESULTS

Gender, age, disease location, duration of symptoms, and use of additional interventional therapies did not differ statistically among the three cohorts. Median hourly infused doses, total doses, infusion times, drug costs, and success rates per limb were: UK, 11.3 (10(4)) U/hour, 4.361 million U, 40.6 hours, US dollars 6577, 97.4%; TPA, 0.57 mg/hour, 21.6 mg, 30.8 hours, US dollars 488, 96.9%; RPA, 0.74 U/hour, 21.4 U, 24.3 hours, US dollars 1787, 100.0%. Major and overall complication rates were: UK, 5.3% and 10.5%; TPA, 3.1% and 12.5%; RPA, 8.3% and 16.7%. Infusion times, success rates, and complications were not statistically different among the three groups. Alteplase and reteplase were significantly less expensive than urokinase (P <.001 and P <.01, respectively).

CONCLUSION

Catheter-directed thrombolysis for the treatment of DVT is safe and effective, regardless of the agent used. However, the new recombinant agents are significantly less expensive than urokinase.

Pharmacologic Agents in Stroke Prevention, Acute Stroke Therapy, and Interventional Procedures

Pharmaceutical agents have moved far beyond just the aspirin and heparin that were the mainstays of stroke and interventional therapy as recently as 10 to 15 years ago. Our understanding of the mechanisms of thrombus formation and vascular response to damage as well as our armamentarium has tremendously improved in the past decade. Direct thrombin inhibitors, powerful antiplatelet agents, new fibrinolytic agents, and statins now allow far greater manipulation of the intraprocedural and postprocedural clot cascade and atherogenesis. It is mandatory that current-day interventionists understand the correct and appropriate use of these agents to achieve the desired outcomes of therapy.

Intrapleural fibrinolysis for parapneumonic effusion and empyema in children

PURPOSE

To assess the safety and efficacy of urokinase and alteplase for intrapleural fibrinolysis in children with parapneumonic pleural fluid collections.

MATERIALS AND METHODS

A retrospective review was performed of 71 children with parapneumonic pleural fluid accumulations who were treated with thoracostomy tube placement and intrapleural instillation of either urokinase or alteplase. The procedures were performed with urokinase between September 2, 1995, and March 27, 1998, and with alteplase between March 30, 1998, and January 2, 2002. The medical records and daily chest radiographs were reviewed by a pediatric radiologist to ascertain demographic information, signs and symptoms, laboratory results, thoracostomy tube output, treatment details, and radiographic pleural thickness and lung opacification. Multiple variables were compared for the alteplase and urokinase groups by using univariate and multivariate statistics. We defined primary treatment success as resolution of signs and symptoms at the time of discharge, without surgical intervention.

RESULTS

Primary treatment success was 98% for alteplase and 100% for urokinase, with no major complications. Greater pleural fluid drainage occurred with alteplase than urokinase during the 1st (P =.001) and 2nd (P =.002) days of fibrinolytic therapy, and for the duration of thoracostomy drainage (P <.001). Multivariate models showed greater total drainage with alteplase (P <.001), greater patient age (P <.001), larger tube size (P =.002), and greater volume of drainage during the 24 hours prior to fibrinolysis (P <.001).

CONCLUSION

Intrapleural fibrinolysis with urokinase or alteplase facilitates thoracostomy tube drainage of parapneumonic pleural fluid. With the dosing regimen used in this study, alteplase produces greater thoracostomy tube output than does urokinase.

The safety, efficacy, and pharmacoeconomics of low-dose alteplase compared with urokinase for catheter-directed thrombolysis of arterial and venous occlusions

PURPOSE

The purpose of this study was to compare the efficacy, complications, and costs associated with low-dose (<2 mg/h) alteplase (tissue plasminogen activator [t-PA]) versus urokinase for the catheter-directed treatment of acute peripheral arterial occlusive disease (PAO) and deep vein thrombosis (DVT).

MATERIALS AND METHODS

A retrospective review was performed during sequential time periods on two groups with involved extremities treated with either t-PA with subtherapeutic heparin (TPA group) or urokinase with full heparin (UK group) at a single center. Treatment group characteristics, success rates, complications, dosages, infusion time, and costs were compared.

RESULTS

Eighty-nine patients with 93 involved limbs underwent treatment (54 with DVT, 39 with PAO). The treatment groups were statistically identical (TPA: 45 limbs; 24 with DVT, 53.3%; 21 with PAO, 46.7%; UK: 48 limbs; 30 with DVT, 62.5%; 18 with PAO, 37.5%). The overall average hourly infused dose, total dose, infusion time, success rates, and cost of thrombolytic agent were as follows (+/- standard deviation): TPA, 0.86 +/- 0.50 mg/h, 21.2 +/- 15.1 mg, 24.6 +/- 11.2 hours, 89.4%, $466 +/- $331; and UK, 13.5 +/- 5.6 (10(4)) U/h, 4.485 +/- 2.394 million U, 33.3 +/- 13.3 hours, 85.7%, $6871 +/- $3667, respectively. Major and minor complication rates were: TPA, 2.2% and 8.9%; and UK, 2.1% and 10.4%, respectively. No statistical differences in success rates or complications were observed; however, t-PA was significantly (P <.05) less expensive and faster than urokinase.

CONCLUSION

Low-dose t-PA combined with subtherapeutic heparin is equally efficacious and safe compared with urokinase. Infusions with t-PA were significantly shorter and less expensive than those with urokinase.

Reteplase for dysfunctional hemodialysis catheter clearance

STUDY OBJECTIVE

To evaluate the efficacy of reteplase administration in clearing hemodialysis catheters.

DESIGN

Open-label, uncontrolled, observational trial.

SETTING

University medical center.

PATIENTS

Thirty-four patients with end-stage renal disease undergoing long-term hemodialysis.

INTERVENTION

Patients had dual-lumen, cuffed, tunneled dialysis catheters placed for long-term vascular access. Reteplase 3 U was instilled into each catheter lumen (total dose 6 U) in the first 20 episodes, 2 U in each catheter lumen (total dose 4 U) in the next 20, and 0.5 U in each catheter lumen (total dose 1 U) in the final 45.

MEASUREMENTS AND MAIN RESULTS

Over 12 months, 85 episodes of catheter dysfunction were documented. Catheter dysfunction was defined as absence of flow from the catheter lumen, inability to aspirate heparin from the lumen, blood flow rates below 150 ml/minute, or venous pressure greater than 250 mm Hg at blood flow rates below 200 ml/minute. Reteplase was instilled into the catheter lumens and allowed to dwell there until the next hemodialysis session. Successful catheter recanalization was defined as return of aspiration and infusion function allowing dialysis to be completed at blood flow rates above 300 ml/minute. Reteplase restored catheter function in 74 (87%) instances of catheter dysfunction. In the first 40 episodes in which 4- or 6-U doses were given, catheter function was restored in 36 instances (90%). There was no difference in restoration of catheter function between 4 U (18/20, 90%) and 6 U (18/20, 90%). In the last 45 cases in which 1 U was administered, function was restored in 38 catheters (84%). Mean overall dwell times were not different between the first 40 (32 +/- 7 hrs) and the last 45 episodes (33 +/- 10 hrs). The overall mean duration of catheter patency was 45 +/- 39 days. Durations of patency in the three dose groups were not significantly different (44 +/- 38, 46 +/- 40, 45 +/- 39 days). No patient suffered adverse effects related to reteplase.

CONCLUSION

Reteplase installation in dysfunctional hemodialysis catheters was effective in restoring catheter function in 87% of episodes. A dose of 1 U appears to be as effective as 4 and 6 U.