Application Of Thrombolytic Therapy Research Articles

Effect of teleconsultation on the application of thrombolytic therapy in stroke patients in the emergency department.

Recently, telemedicine has become a widely used method worldwide for the treatment of patients with acute ischemic stroke in hospitals where neurologists are unavailable. The purpose of this study was to determine the accuracy and reliability of treatment decisions made by remote neurologists via teleconference assisted by emergency physicians in acute stroke cases and to determine whether the use of teleconsultation would lead to any delays in assessment and treatment decisions. This single-center and prospective study was performed with 104 patients who met the inclusion criteria. Patients were concurrently assessed by a teleneurologist (TN) experienced in stroke and an on-site neurologist (OS-N). The TN performed their assessment via teleconference and assisted by an emergency physician for test results and physical examination. NIHSS (The National Institutes of Health Stroke Scale) scores, assessment times, treatment decisions by the two neurologists, and patient outcomes were recorded separately. The TN was asked to rate the quality of communication. Of the 104 patients in the study, 59.6% (n = 62) were men and the median age was 66 (interquartile range = 56-78) years. The median duration of assessment by the OS-N was 30 (18-45) min and the median duration of assessment by the TN was 6 (5-8) min; the duration of assessment by the TN was significantly shorter (6.56 min vs. 33.35 min; Z = 8.669; p < 0.001). The median rating assigned by the TN to the quality of teleconsultation was 5.0 (4.25-5.0) (Table 1). The NIHSS scores assigned by both neurologists showed significant correlation (p < 0.001). Analysis of the agreement between the OS-N and TN in their treatment decisions yielded a Kappa value of 74.3% for interrater agreement. Teleconsultation was a successful and reliable strategy in assessing patients with ischemic stroke and making decisions for IV-tPA. Moreover, patient assessment via teleconsultation was less time consuming. The results of the study are promising for the use of teleconsultation in the future.

Right cervical internal carotid artery dissection as the initial presentation in a patient with clinically diagnosed segmental arterial mediolysis

A 46-year-old man developed acute-onset right cervical internal carotid artery occlusion at its origin, and concomitant multiple visceral artery aneurysms were also detected during the evaluation of cerebral infarction. Follow-up cerebral angiography confirmed the irregular and beaded appearance of the right cervical internal carotid artery, presumably secondary to dissection. The clinical and radiological findings in the patient were most consistent with segmental arterial mediolysis, and we considered that segmental arterial mediolysis might be the cause of internal carotid artery dissection. The typical presentation of segmental arterial mediolysis is acute fetal intra-abdominal hemorrhage as a result of dissection of visceral artery aneurysms. Hence, physicians should be aware of segmental arterial mediolysis in the differential diagnosis of internal carotid arterydissection and carefully assess the application of thrombolytic therapy.

Magnetic resonance imaging criteria for thrombolysis in hyperacute cerebral infarction.

Purpose: Selection of patients with cerebral infarction for MRI that is suitable for thrombolytic therapy as an emerging application. Although the efficiency of the therapy with i.v. tissue plasminogen activator (tPA) within 3 hours after onset of symptoms has been proven in selected patients with CT, now these criteria are determined by MRI, as the data we gather are fast and accurate in the first hours. Material and methods: MRI screening in patients with acute cerebral infarction before application of thrombolytic therapy was done in a UCC Mannheim in Germany. Unlike trials with CT, MRI studies demonstrated the benefits of therapy up to 6 hours after the onset of symptoms. We studied 21 patients hospitalized in Clinic of Neuroradiology at University Clinical Centre in Mannheim-Germany. They all undergo brain MRI evaluation for stroke. This article reviews literature that has followed application of thrombolysis in patients with cerebral infarction based on MRI. Results: We have analyzed the MRI criteria for i.v. application of tPA at this University Centre. Alongside the personal viewpoints of clinicians, survey reveals a variety of clinical aspects and MRI features that are opened for further more exploration: therapeutic effects, the use of the MRI angiography, dynamics, and other. Conclusions: MRI is a tested imaging method for rapid evaluation of patients with hyperacute cerebral infarction, replacing the use of CT imaging and clinical features. MRI criteria for thrombolytic therapy are being applied in some cerebral vascular centres. In Kosovo, the application of thrombolytic therapy has not started yet.

A novel hollow flexible wire allows the safe and effective local application of thrombolytic therapy in a mouse model of deep vein thrombosis

Purpose: Severe cases of deep vein thrombosis (DVT) may require thrombolysis in order to prevent further complications such as embolism, postthrombotic syndrome, or edema. Moreover, patients with thrombotic occlusion of small vessels of the eye or brain may benefit from a precisely guided application of local thrombolytic therapy. Small veins are particularly fragile and require gentle means of local drug infusion to avoid vessel wall perforation. Here, we introduce a new way of thrombolysis therapy application using a hollow flexible wire. Aims: To test the feasibility of local thrombolytic therapy via hollow flexible wire in a mouse model of DVT. Methods: Inferior vena cava (IVC) thrombosis was induced in C57Bl/6 mice by vessel wall exposure to a filter paper saturated with 10% ferric chloride for 15 minutes after laparatomy in anesthesized mice. Thrombus formation was visualized by intravital microscopy of rhodamine-labeled platelets and leukocytes. A nitinol hypotube coronary wire with perforated platinum tip was inserted via a 0,8 x 40 mm canula into the IVC lumen distal to the site of ferric chloride exposure. Either tPA (alteplase, 1.5mg/kg) or saline (control) was administered for 1 minute via the platinum wire without mechanical fragmentation of the thrombus. Thrombus size was assessed by immunohistochemistry (platelet CD41 staining). Results: Intravital microscopy of the ferric chloride-exposed IVC depicted platelet-containing thrombus growth until initiation of local thrombolytic treatment. Alteplase administration resulted in the resolution of thrombi within 2-5 minutes. Histology revealed a marked decrease in thrombus size in IVC cross-sections of alteplase-treated mice (22.7%±0.9% vein occlusion as compared to 85.6%±7.5% vein occlusion in saline treated mice). Bleeding complications were not increased in alteplase treated mice. Conclusions: We demonstrate that a flexible hollow wire enables the successful application of thrombolytic therapy to IVC thrombi in mice without vessel wall perforation. Flexible wire based-thrombolytic therapy appears to be a safe and reliable method for thrombus dissolution in fragile small veins. Wire-based thrombolytic therapy may become a promising strategy in the management of small vessel thrombosis and may improve targeted therapy.

Early CT signs of cerebral infarction: Incidence and significance

Objective. Computerized tomography (CT), as an imaging method, has a key role in brain infarct diagnosis, and from aspect of modern therapy the most important are the first three hours of disease ('therapeutic window'), when application of thrombolytic therapy is possible, which leads to the more favorable outcome. Study aim was to determine possibilities of CT in detection and evaluation of early signs of brain infarct. Methods. Investigation represents four-year long prospective study, in period March 2002 - February 2006, and included 187 patients with suspicion of having acute ischemic stroke. Among early signs of ischemic stroke, hemisphere hypodensity (or part of it), 'insular ribbon' sign, obscuration of lentiform nucleus, cortical sulci loss and hyperdensity of middle cerebral artery (HMCAS), internal carotid artery (HICAS) and posterior cerebral artery (HPCAS), were monitored. Results. Confirmation of stroke did not much influence loss of 'insular ribbon' and lentiform nucleus, and hyperdensity in regions of MCA, ICA and PCA. Only appearance of hypodensity, loss of cortical sulci and timing had an effect on infarct confirmation. Conclusion. Our results suggest that in early infarct detection CT is of great importance, and that the key early infarct signs are hypodensity and cortical sulci loss, and to a lesser degree insular ribbon loss and MCA hyperdensity. An early appearance of brain edema has the highest influence on mortality rate. Appearance of early signs of embolism (HICAS and HMCAS) in the first three hours after attack, combined with early appearance of hyperdensity, represent a bad prognostic sign.

Thrombolysis in the Treatment of Acute Ischaemic Stroke

Stroke kills 4.4 million individuals annually and is the most significant cause of somatic disability. Ultra-acute thrombolysis is the only proven specific medical therapy for stroke, but the pharmacoeconomic consequences of wide application of thrombolytic therapy have not been broadly reported. This review analyses available data on costs incurred by stroke morbidity and estimates how these might be influenced by thrombolytic therapy. These analyses are supported by: (i) estimated lifetime costs of stroke therapy (approximately $US60 000 per patient); (ii) a speculative example of thrombolytic therapy simulated in the setting of a comprehensive urban stroke centre; and (iii) recent data on the efficacy of thrombolysis in reducing disability. It is estimated that only 5% of acute stroke patients are eligible for thrombolysis, which prevents 1 case of long term disability among every 7 patients treated.

Successful Thrombolytic Therapy for Massive Pulmonary Embolism

The use and scope of thrombolytic therapy in the management of pulmonary embolism (PE) continues to evolve. The results of small studies suggest that thrombolytic therapy might have an impact on survival in massive PE with cardiogenic shock; however, no large studies to further this notion exist. Furthermore, the expanded application of thrombolytic therapy to patients with PE and right ventricular dysfunction (RVD) but without overt hemodynamic collapse remains controversial. We report successful use of the thrombolytic agent tissue plasminogen activator (tPA) in the management of life-threatening PE with RVD without overt cardiovascular collapse. We present evidence for the meritorious use of thrombolytic therapy in this category of PE patients. We believe that a broadened application of thrombolytic therapy to patients with PE and RVD but without cardiogenic shock, especially in younger patients, is beneficial and worth the risk.

Development and Pathophysiological Basis of Thrombolytic Therapy in Acute Myocardial Infarction Part II. 1977‐1980 The Pathogenetic Role of Thrombus Is Established by the Goettingen Pilot Studies of Mechanical Interventions and Intracoronary Thrombolysis in Acute Myocardial Infarction

Between 1977 and 1980, our group performed immediate coronary angiography in 158 patients admitted with acute myocardial infarction (MI) at the University of Goettinger, Germany. From June 1978 to May 1979, our pioneering study of mechanical transcatheter recanalization of acute total coronary artery occlusions using guidewires and tapered catheters was performed. Restoration of antegrade flow in 7 of 13 patients was associated with an improvement in left ventricular function not seen in historical controls. From June 1979 to December 1980, the pathogenetic role of thrombus and spasm in acute coronary syndromes was explored in our pioneering study of intracoronary streptokinase infusion. Following injection of nitroglycerin, streptokinase was selectively infused at a rate of 2000 U/minute for 50–95 minutes. Only four of the initial 22 infarct patients showed improvement of antegrade flow following intracoronary nitroglycerin alone. Reopening of the completely obstructed vessel or increase in lumen diameter at the site of subtotal occlusion occurred in 22 of 29 infarct patients within 15–90 minutes of streptokinase infusion but in none of the five patients with unstable angina. Chest pain was alleviated and left ventricular function was improved significantly after successful lysis. The first presentation of both our mechanical and pharmacological interventions in acute MI to a large international audience at the annual American Heart Association meeting in 1979 convinced clinicians of the etiologic role of fibrin‐rich coronary thrombus in acute MI. The demonstration of rapid restoration of antegrade flow initiated a worldwide renaissance in the application of thrombolytic therapy and paved the way for primary angioplasty in acute MI.

Thrombolysis for acute pulmonary embolism: Are the risks worth the benefits?

The successful application of thrombolytic therapy to the treatment of acute myocardial infarction has stimulated similar attempts to apply thrombolytic therapy to the treatment of acute pulmonary embolism. The development of newer thrombolytic agents and improved protocols for dosing and delivering thrombolytic therapy have provided additional insight into the risks and potential benefits of thrombolysis for acute pulmonary embolism. The purpose of the present review is to examine the risks and benefits of thrombolytic therapy for pulmonary embolism in light of recent investigations.

Application of thrombolytic therapy in vascular occlusive disease: A surgical view

The use of fibrinolytic agents to control the fibrinolytic enzyme system and lyse pathologic fibrin deposits or thrombus has now assumed a position with anticoagulants and vascular surgery in the physician's therapeutic armamentarium. The principal exogenous activators that are used clinically are streptokinase, urokinase, and tissue plasminogen activator. Acute arterial occlusions are more likely than chronic occlusions to respond to thrombolytic therapy, especially if treatment is instituted within a few hours of onset of symptoms and if the disease is due to embolic material rather than in situ thrombosis. Since the duration of drug infusion necessary to lyse arterial thrombus cannot be predicted, patients in whom tissue viability cannot be determined or in whom ischemia cannot be tolerated during the drug infusion interval are not candidates for intraarterial fibrinolytic drug infusion. In treating patients with venous occlusion, thrombolytic therapy is more effective against proximal clots than in calf thrombosis. No protective effect from pulmonary embolism has been noted in trials comparing heparin with streptokinase. Fifty percent of patients with an initial episode of deep venous thrombosis treated within 72 hours of onset will have complete resolution of thrombus with preservation of valve function.