warfarin and Carotid-Artery-Thrombosis

A 49-year-old man was transferred to our hospital with chief complaint of global aphasia and weakness of right upper and lower limbs. Brain MRI showed ultra-acute cerebral infarction in left anterior cerebral artery and middle cerebral artery territory and MRA showed occlusion of A2 and M2. Although t-PA was administrated intravenously, symptoms didn't improve and giant internal carotid thrombus (size 6 × 7 × 17 mm) was recognized at left internal carotid artery by carotid ultrasonography. After started anticoagulant therapy, thrombus was miniaturized gradually and finally disappeared. Anticoagulant therapy is effective to internal carotid thrombus and carotid ultrasonography is useful to confirm the effectiveness. We suggest that clinicians should enforce anticoagulant therapy for the first choice to internal carotid thrombus.

Topics: Anticoagulants; Brain Infarction; Carotid Artery Thrombosis; Carotid Artery, Internal; Heparin; Humans; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Male; Middle Aged; Treatment Outcome; Ultrasonography; Warfarin

The presence of a carotid stenosis, a floating thrombus, and a patient with clinical and CT evidence of a stroke represents a significant therapeutic dilemma to the clinician. The evidence of a stroke precludes any active treatment of the carotid stenosis safely, while the floating thrombus demands immediate attention. We recently were involved with just such a patient and chose a conservative approach of anticoagulation followed by operative intervention several weeks later.

Topics: Anticoagulants; Carotid Artery Thrombosis; Carotid Artery, Internal; Carotid Stenosis; Cerebral Angiography; Clopidogrel; Endarterectomy, Carotid; Heparin; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Stroke; Ticlopidine; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; Warfarin

The aim of this study was to define the optimal treatment for patients with symptomatic intraluminal carotid artery thrombus (ICAT).. The authors performed a retrospective chart review of patients who had presented with symptomatic ICAT at their institution between 2001 and 2011.. Twenty-four patients (16 males and 8 females) with ICAT presented with ischemic stroke (18 patients) or transient ischemic attack ([TIA], 6 patients). All were initially treated using anticoagulation with or without antiplatelet drugs. Eight of these patients had no or only mild carotid artery stenosis on initial angiography and were treated with medical management alone. The remaining 16 patients had moderate or severe carotid stenosis on initial angiography; of these, 10 underwent delayed revascularization (8 patients, carotid endarterectomy [CEA]; 2 patients, angioplasty and stenting), 2 refused revascularization, and 4 were treated with medical therapy alone. One patient had multiple TIAs despite medical therapy and eventually underwent CEA; the remaining 23 patients had no TIAs after treatment. No patient suffered ischemic or hemorrhagic stroke while on anticoagulation therapy, either during the perioperative period or in the long-term follow-up; 1 patient died of an unrelated condition. The mean follow-up was 16.4 months.. Results of this study suggest that initial anticoagulation for symptomatic ICAT leads to a low rate of recurrent ischemic events and that carotid revascularization, if indicated, can be safely performed in a delayed manner.

Topics: Adult; Aged; Anticoagulants; Aspirin; Brain Ischemia; Carotid Arteries; Carotid Artery Thrombosis; Carotid Stenosis; Cerebral Angiography; Endarterectomy, Carotid; Female; Humans; Male; Middle Aged; Platelet Aggregation Inhibitors; Retrospective Studies; Stroke; Treatment Outcome; Warfarin

Topics: Adult; Angiography, Digital Subtraction; Anticoagulants; Aphasia; Carotid Artery Thrombosis; Coronary Angiography; Humans; International Normalized Ratio; Magnetic Resonance Imaging; Male; Middle Aged; Neurologic Examination; Paresis; Patient Care Planning; Recovery of Function; Stroke; Tomography, X-Ray Computed; Warfarin

Hemorrhage is a major complication of thrombolytic treatment. Concerns have been raised about the risk of hemorrhage in patients having received warfarin. Therefore, different indications for thrombolytic treatment are in use for stroke patients on warfarin. However, it remains uncertain whether the prior warfarin use actually increases their risk of bleeding in patients treated with thrombolysis.. This study included 179 consecutive patients who had high-risk cardioembolic sources and received thrombolytic treatment. Patients were treated with intravenous thrombolytic agents, or underwent intraarterial thrombolysis if their international normalized ratio (INR) was ≤1.7. We compared the frequency of bleeding complications between patients with prior warfarin use and those without. We also investigated whether there were differences in functional outcome and recanalization rates between them.. A prior warfarin use was present in 28 patients (15.6%). Although INR levels were higher in the prior warfarin group, the frequency of bleeding complications was not different between patients who received prior warfarin and those who did not. No differences were observed in patients with or without prior warfarin use, for successful recanalization rate (Thrombolysis in Myocardial Infarction grade 2 or 3), mortality, or modified Rankin score (≤2) at 3months.. Thrombolytic therapy for patients who previously received warfarin and had an INR≤1.7 did not affect bleeding risk, clinical outcome, or recanalization rate. Our data suggest that patients with a history of prior warfarin use may be safely treated with thrombolytic agents when their INR levels are low.

Topics: Adult; Aged; Aged, 80 and over; Aging; Anticoagulants; Brain Ischemia; Carotid Artery Thrombosis; Cerebral Angiography; Cerebral Hemorrhage; Embolism; Female; Fibrinolytic Agents; Heart; Humans; International Normalized Ratio; Magnetic Resonance Angiography; Magnetic Resonance Imaging; Male; Middle Aged; Prognosis; Risk Factors; Sex Characteristics; Stroke; Tomography, X-Ray Computed; Treatment Outcome; Warfarin

The objective of this study was to evaluate the safety and efficacy of carotid artery stenting (CAS) in high-risk patients. Carotid endarterectomy (CEA) has been shown to be more effective than medical therapy but has limitations. CAS may be a reasonable alternative, particularly in high-risk patients. The authors evaluated prospectively the safety and efficacy of CAS in 299 consecutive patients who underwent CAS of 343 extracranial carotid arteries. Of the patients enrolled, 210 (70%) would have been excluded from the major trials of CEA, and 84 (28%) were referred by vascular surgeons. This series represents a very high-risk group that included patients with unstable angina, previous ipsilateral CEA, contralateral carotid occlusion, and other severe comorbid illnesses. Seventy-four (25%) patients were aged 80 years or more. All patients had independent neurologic examination before and after the procedure. Three hundred seventy-six stents were deployed in 343 arteries. Procedural success was 99%. Mean stenosis was 75 +/- 12% before and 7 +/- 8% after the procedure. Ninety-two patients had coronary intervention. Only 56 (19%) patients were North American Symptomatic Carotid Endarterectomy Trial (NASCET) eligible. During the initial hospitalization and 30 days post-CAS, there were two (0.6%) major and seven (2.3%) minor strokes. There were no myocardial infarctions or deaths during or within 30 days of CAS. None of the NASCET-eligible patients had a stroke. At a mean follow-up period of 26 +/- 13 months, eight (2.7%) patients had asymptomatic restenosis. No additional major strokes or neurologic deaths occurred. In conclusion, CAS is feasible, can be performed even in high-risk patients, and is associated with a low restenosis rate.

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Blood Vessel Prosthesis Implantation; Carotid Artery Thrombosis; Carotid Artery, Common; Carotid Stenosis; Female; Follow-Up Studies; Humans; Male; Maryland; Middle Aged; Postoperative Complications; Radiography; Severity of Illness Index; Stents; Time; Time Factors; Treatment Outcome; Warfarin

The antithrombotic efficacy of AT-1459, a novel, direct thrombin inhibitor (Ki = 4.9 nM) was evaluated in rat models of venous thrombosis combined with a bleeding time test and arterial thrombosis. After drugs were given by i. v. bolus injection plus a continuous infusion, the ID50, (a dose that exhibits 50% inhibition of thrombus formation over each vehicle group) values of AT-1459, argatroban, and dalteparin were 0.04 mg/kg plus 0.04 mg/kg/h, 0.1 mg/kg plus 0.4 mg/ kg/h, and 13.0 IU/kg plus 26.0 IU/kg/h, respectively, in the venous thrombosis study. The BT2 (a dose that causes 2-fold prolongation of bleeding time over each vehicle group) values of AT-1459, argatroban, and dalteparin were 0.9 mg/kg plus 0.9 mg/kg/h, 1.0 mg/kg plus 0.6 mg/kg/h, and 345.5 IU/kg plus 691.0 IU/kg/h in the rat tail transection model. The ratios of BT2/ID50 of AT-1459, argatroban, and dalteparin were 22.5, 10.0, and 26.6, respectively. In a rat model of arterial thrombosis induced by topical FeCl2 application, intravenous administration of AT-1459, argatroban, and dalteparin improved the vessel patency significantly (P < 0.01) at 0.6 mg/kg plus 0.6 mg/kg/h, 0.6 mg/kg plus 2.4 mg/kg/h, and 300 IU/kg plus 600 IU/kg/h, respectively. The oral antithrombotic effect of AT-1459 lasted for 6 after administering 30 mg/kg and improved the vessel patency significantly 1 h after administering the same dose in venous and arterial thrombosis models, respectively, with a rapid onset of action. Warfarin also inhibited thrombus weight and improved the vessel patency significantly after oral administration of 0.3 mg/kg for three consecutive days in the same study. The antithrombotic and hemorrhagic effects of all drugs studied were correlated with plasma concentration or clotting times. These results suggest that AT-1459 may be clinically useful as an orally available antithrombotic agent for the prevention of venous and arterial thrombosis.

Topics: Administration, Oral; Amidines; Animals; Arginine; Azepines; Bleeding Time; Carotid Artery Thrombosis; Dalteparin; Drug Evaluation, Preclinical; Fibrinolytic Agents; Hemorrhage; Humans; Infusions, Intravenous; Injections, Intravenous; Male; Molecular Structure; Pipecolic Acids; Rats; Rats, Sprague-Dawley; Sulfonamides; Thrombin; Vena Cava, Inferior; Venous Thrombosis; Warfarin

Topics: Animals; Aspirin; Blood Cell Count; Carotid Artery Thrombosis; Catheterization; Disease Models, Animal; Fibrinolytic Agents; Heparin; Male; Rats; Time Factors; Warfarin

These studies describe experimental conditions where aspirin is less effective than other antiplatelet and anticoagulant drugs in inhibiting acute arterial thrombosis. External electrolytic injury of the rat carotid artery was used to induce occlusive thrombi in 97% of vehicle-treated rats. Thrombi were revealed by light and electron microscopy to be comprised primarily of platelets enmeshed in a fibrin network. The thrombin inhibitor D-phenylalanyl-L-prolyl-L-arginyl chloromethylketone (PPACK; 6 mg/kg, i.v.) decreased thrombus weight by 90%. Aspirin alone (1, 10 and 30 mg/kg, i.v.), dipyridamole alone (5 mg/kg i.v.) and aspirin (1 and 10 mg/kg, i.v.) in combination with dipyridamole (5 mg/kg, i.v.) did not inhibit thrombosis. The platelet-activating factor (PAF) antagonist, WEB 2086, (1 mg/kg i.v.) was also ineffective. Other drugs had intermediate activity. Thrombi were decreased 56% by the thromboxane receptor antagonist, BMS 180,291, either alone (5.8 mg/kg i.v.) or in combination with aspirin (10 mg/kg, i.v.). Heparin (900 U/kg, i.v.), warfarin (0.25 mg/kg, p.o. once daily for 3 days) and ticlopidine (200 mg/kg, p.o. once daily for 3 days) reduced thrombus weight by 63, 73 and 43% respectively. Reductions in thrombus weight were always associated with improvements in either average blood flow or vessel patency.

Topics: Amino Acid Chloromethyl Ketones; Animals; Aspirin; Azepines; Bridged Bicyclo Compounds, Heterocyclic; Carotid Artery Thrombosis; Dipyridamole; Fibrinolytic Agents; Heparin; Male; Oxazoles; Propionates; Rats; Rats, Sprague-Dawley; Thrombolytic Therapy; Ticlopidine; Triazoles; Warfarin

Platelet-dependent occlusive thrombosis at sites of deep vessel wall injury elicited by electrical stimulation of rat carotid arteries was significantly reduced by thromboxane A2 (TXA2) synthetase inhibition and/or TXA2/prostaglandin endoperoxide receptor antagonism (ridogrel 1.25 mg/kg i.v.; dazoxiben 5 mg/kg i.v.; sulotroban 20 mg/kg i.v.), by inhibition of ADP-dependent platelet responses (ticlopidine 3 x 200 mg/kg orally) and by anticoagulation (heparin 250 U/kg i.v.; warfarin 1.25 mg/kg i.p.). This points to an involvement of arachidonic acid metabolites, ADP and thrombin as modulators of the thrombotic process. The antithrombotic effect of ridogrel (IC50 = 0.22 mg/kg i.v.) was abolished by cyclooxygenase inhibition (suprofen 5 mg/kg i.v.) but enhanced by cAMP phosphodiesterase inhibition (HL 725 6 micrograms/kg/min i.v.), demonstrating the importance of platelet inhibitory prostanoids such as PGD2, and prostacyclin formed after TXA2 synthetase inhibition. High doses of ridogrel (1.25 mg/kg i.v.) producing additional TXA2/prostaglandin endoperoxide receptor antagonism were more effective than lower doses (0.16 mg/kg i.v.) providing TXA2 synthetase inhibition alone. The antithrombotic effect of ridogrel, when combined with ticlopidine or heparin, exceeded that of the single compounds, pointing to interactions between arachidonic acid metabolites, ADP and thrombin in the formation of occlusive thrombosis at sites of arterial injury.

Topics: Adenosine Diphosphate; Animals; Anticoagulants; Arachidonic Acid; Arachidonic Acids; Blood Coagulation; Blood Platelets; Carotid Artery Thrombosis; Electric Stimulation; Heparin; Male; Pentanoic Acids; Pyridines; Rats; Rats, Inbred Strains; Receptors, Prostaglandin; Receptors, Thromboxane; Thrombin; Thromboxane-A Synthase; Ticlopidine; Warfarin

1. Thrombus formation induced by electrical stimulation of the carotid artery was investigated in anesthetized rabbits and rats. Occlusive Grade III thrombi were produced consistently in 34 normal New Zealand rabbits and 58 untreated albino Wistar rats. Thrombus formation was monitored continuously in some of the animals with a magnetic flowmeter or a thermistor probe applied on the carotid. 2. The usefulness of the model for the screening of drugs was tested by treating the animals with warfarin, heparin, prostacyclin (PGI2), dihydroprostacyclin (DiHPGI2), prostaglandin E1 (PGE1), and prostaglandin D2 (PGD2). 3. All of the drugs except warfarin were infused continuously into the venous circulation during the entire experimental period at a rate of 0.2 ml/min. 4. Warfarin (10 mg/kg), administered by gavage 24 h before the experiment, prevented thrombus formation, as did heparin iv (greater than 34 U/kg). 5. Of the four platelet antiaggregatory prostaglandins tested, PGI2 was the most potent inhibitor of thrombus formation and DiHPGI2 the least active, as evaluated by visual inspection of stimulated arterial segments which were excised 30 min (rabbits) or 15 min (rats) after the stimulation was stopped. PGI2 was less active in rats than in rabbits (Threshold Protective Dose ratio ca. 4:1). PGE1 and PGD2 showed intermediate activity in both animal models.

Topics: Animals; Carotid Artery Thrombosis; Disease Models, Animal; Electric Stimulation; Epoprostenol; Female; Heparin; Male; Prostaglandins; Prostaglandins D; Prostaglandins E; Rabbits; Rats; Rats, Inbred Strains; Warfarin

Eight patients with transient ischemic attacks, and three with partial nonprogressive strokes associated with mitral valve prolapse, are reported. No other etiology for their ischemic events was found. Only one episode of ischemia recurred on aspirin treatment, whereas none recurred on sodium warfarin therapy.

Topics: Adult; Aged; Aspirin; Carotid Artery Thrombosis; Cerebrovascular Disorders; Dipyridamole; Echocardiography; Electrocardiography; Female; Heparin; Humans; Ischemic Attack, Transient; Male; Middle Aged; Mitral Valve Prolapse; Recurrence; Warfarin

Topics: Atrial Fibrillation; Carotid Artery Thrombosis; Humans; Male; Mandible; Medical History Taking; Middle Aged; Molar; Patient Care Planning; Periodontal Diseases; Preanesthetic Medication; Prothrombin Time; Tooth Extraction; Warfarin

Topics: Angiography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Carotid Artery Thrombosis; Carotid Artery, Internal; Cerebral Angiography; Geriatrics; Heparin; Humans; Pathology; Warfarin

Topics: Angina Pectoris; Anticoagulants; Carotid Artery Thrombosis; Diabetic Angiopathies; Fibrinolysis; Gangrene; Heart Failure; Humans; Myocardial Infarction; Raynaud Disease; Thromboangiitis Obliterans; Thromboembolism; Warfarin