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Dan Atar

Publications and source records attributed to Dan Atar.

At least 19 recordsLinked to original sources
PubMed2006

Assessment of bleeding events in clinical trials--proposal of a new classification.

Present classifications of bleeding events used in antithrombotic and/or antiplatelet clinical trials are based on the criteria developed by the Thrombolysis In Myocardial Infarction (TIMI) and Global Use of Strategies to Open Coronary Arteries (GUSTO) groups. Introduced more than a decade ago, the 2 classifications used the criteria to better categorize hemorrhagic events after therapy with thrombolytic agents. Recent advances in interventional cardiology, resulting in a domination of percutaneous intracoronary procedures over systemic drug-induced thrombolysis, have substantially changed the clinical characteristics and magnitude of bleeding complications. Moreover, disturbances of the coagulation cascade, as well as platelet inhibition caused directly by antithrombotic and antiplatelet agents, share very specific and well-recognized clinical features not reflected in the existing classifications. Bleeding events after aspirin or clopidogrel, and especially those after more delicate antiplatelet regimens with dipyridamole used in patients after ischemic stroke or transient ischemic attack, are impossible to classify by the present guidelines, other than categorically triaging them altogether to the "minor" category. Uniting entirely different bleeding events as "minor" under-rates their importance and diminishes affiliated risks, creating an illusion that they do not require monitoring and/or changes in antiplatelet or antithrombotic regimens. In reality, such unrecognized and unreported mild complications may transform into more serious bleeds or lead to noncompliance. Unauthorized withdrawal from antiplatelet agents in turn causes rebound platelet activation and higher risk for secondary vascular events. In conclusion, a new classification of bleeding events is introduced (the BleedScore), based on a point accumulation depending on the severity of hemorrhage, which is believed to be more suitable for the assessment of modern, more delicate antithrombotic and antiplatelet therapies, particularly for their realistic assessment in clinical trials.

Clinical Trials as Topic↗
PubMed2006

Frequency and significance of troponin T elevation in acute ischemic stroke.

Elevated levels of troponin have been reported in patients with acute ischemic stroke. In this prospective study, the prevalence and characteristics of troponin elevation were examined in 244 patients with acute ischemic stroke but without overt ischemic heart disease. Troponin T (TnT) and creatine kinase-MB (CK-MB) concentrations were measured and 12-lead electrocardiograms obtained daily during the first 5 days of admission. Myocardial perfusion scintigraphy was performed in patients with TnT levels of 0.10 micro g/L and in comparable controls without elevation of TnT. Patients were followed for a mean of 19 +/- 7 months, with all-cause mortality as the clinical end point. Elevated levels of TnT (>0.03 micro g/L) and creatine kinase-MB (> or =10 micro g/L) were observed in 10% and 9% of patients, respectively. Patients with elevated TnT had higher frequencies of heart and/or renal failure. Perfusion abnormalities on myocardial perfusion scintigraphy at rest were not more frequent or pronounced in patients with TnT levels of > or =0.10 micro g/L than in the control group. Only 7 patients (3%) had elevations of TnT or creatine kinase-MB and electrocardiographic changes suggesting acute myocardial infarctions. According to univariate and multivariate analyses, elevation of TnT was significantly associated with mortality. In conclusion, elevated levels of TnT are rare in patients presenting with ischemic stroke but without overt ischemic heart disease. Heart and renal failure rather than myocardial infarction are the most likely causes. When present, elevation of TnT seems to be useful in identifying patients who are at increased risk of dying within the following 2 years.

Aged↗
PubMed2006

Time course of degradation of cardiac troponin I in patients with acute ST-elevation myocardial infarction: the ASSENT-2 troponin substudy.

Although measurement of troponin is widely used for diagnosing acute myocardial infarction (AMI), its diagnostic potential may be increased by a more complete characterization of its molecular appearance and degradation in the blood. The aim of this study was to define the time course of cardiac troponin I (cTnI) degradation in patients with acute ST-elevation myocardial infarction (STEMI). In the ASSENT-2 substudy, 26 males hospitalized with STEMI were randomized to 2 different thrombolytic drugs within 6 hours after onset of symptoms. Blood samples were obtained just before initiation of thrombolysis and at 30 minutes intervals (7 samples per patient). Western blot analysis was performed using anti-cTnI antibodies and compared with serum concentrations of cTnI. All patients exceeded the cTnI cutoff for AMI during the sampling period; at initiation of therapy, 23 had elevated cTnI values. All patients demonstrated 2 bands on immunoblot: intact cTnI and a single degradation product as early as 90 minutes after onset of symptoms. On subsequent samples, 15 of 26 patients showed multiple degradation products with up to 7 degradation bands. The appearance of fragments was correlated with higher levels of cTnI (P<0.001) and time to initiation of treatment (P=0.058). This study defines for the first time the initial time course of cTnI degradation in STEMI. Intact cTnI and a single degradation product were detectable on immunoblot as early as 90 minutes after onset of symptoms with further degradation after 165 minutes. Infarct size and time to initiation of treatment was the major determinant for degradation.

Adult↗
PubMed2006

Rationale and design of the 'F.I.R.E.' study. A multicenter, double-blind, randomized, placebo-controlled study to measure the effect of FX06 (a fibrin-derived peptide Bbeta(15-42)) on ischemia-reperfusion injury in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention.

Immediate reopening of acutely occluded coronary arteries via primary percutaneous coronary intervention (PCI) is the treatment of choice to salvage the ischemic myocardium in the setting of ST-segment elevation myocardial infarction (STEMI). However, the sudden re-initiation of blood flow achieved with PCI can lead to a local acute inflammatory response with further endothelial and myocardial damage. This phenomenon, described as 'reperfusion injury', has been recognized for several decades, yet no pharmacologic intervention has so far succeeded in reducing myocardial damage linked to reperfusion. FX06 is a naturally occurring peptide derived from the neo-N-terminus of fibrin (Bbeta(15-42)). It prevents leukocyte migration through the gap junctions of endothelial cells. Experimental studies have shown that FX06 inhibits the binding of the proinflammatory fibrin E1 fragment to VE-cadherin expressed in the adherence junction. It represents a novel approach to reducing local and systemic inflammation, including myocardial reperfusion injury, in the adherens junction. The present multicenter, double-blind, randomized, placebo-controlled study is designed to test the hypothesis that FX06 injection during and immediately after primary PCI can reduce infarct size in patients with STEMI. The primary outcome measure of efficacy in this study is the degree of myocardial salvage calculated as the difference between the perfusion defect before and after PCI, determined by myocardial perfusion scintigraphy during rest. Further, infarct size at the end of the index hospitalization, as well as at 4 months, will be measured by cardiac magnetic resonance imaging. The present position paper describes the rationale, design and the methods utilized in this trial.

Angioplasty, Balloon, Coronary↗
PubMed2006

FDA and CPMP rulings on subgroup analyses.

The extent to which subgroup analyses should affect the interpretation and conclusions in a trial report is a contentious matter, and guidelines regarding this issue have been established by the US Food and Drug Administration (FDA) and the EU Committee for Proprietary Medicinal Products (CPMP). Subgroup analyses should be set out in the protocol of clinical trials. The treatment effect itself may vary within a subgroup or covariate. In some cases, interactions are anticipated or are of particular a priori interest; hence a subgroup analysis or a statistical model including interactions is part of the planned analysis. However, subgroup or interaction analyses are often merely exploratory and should be clearly identified as such in the protocol. When exploratory, these analyses should be interpreted cautiously. Market approval of a compound is based on the overall trial results, and, importantly, no drug has so far been approved or not-approved either in the US or in the EU on the basis of subgroup analysis. However, subgroup analysis can influence the approval or can even be required, and therefore it can influence the labelling of the Summary Characteristics of a Product. Two examples in heart failure are given by the Val-HeFT trial comparing valsartan to placebo and the MERIT-HF trial comparing metoprolol to placebo, from which some remarkable regulatory issues arose that were debated by the FDA and CPMP.

Clinical Trials as Topic↗
PubMed2006

Medical and ventilatory treatment of acute heart failure: new insights.

BACKGROUND: The traditional medical treatment of acute heart failure (AHF) has remained unchanged for many years. It has been based on oxygen supplementation and mechanical ventilatory support as well as the administration of morphine, diuretics, nitrates and inotropic agents. In 2005 the European Society of Cardiology (ESC) published new guidelines on the diagnosis and treatment of AHF. Also, new therapies have been introduced recently, giving rise to changes in therapeutic concepts. MATERIAL/METHOD: Based on these new guidelines and recent studies selected from the literature we here describe the new ESC classification of AHF including its epidemiology and pathophysiology. We further present a state-of-the-art status of the choices of medical treatment for patients with acute decompensated heart failure and pulmonary edema. RESULTS: Mechanical ventilatory support reduces the number of patients who require endotracheal intubation. Nitrates in dosages higher than employed today appear to be beneficiary to patients with pulmonary congestion, probably because of the pronounced afterload-reducing effect. Nesiritide, a synthetic brain natriuretic peptide, has shown better hemodynamic effects than common nitrate dosages in patients with congestive heart failure. Tezosentan, an endothelin antagonist, was tested in the biggest AHF trial ever, which, however, was terminated prematurely because it was futile to proceed given the endpoints dyspnea and death. The beta1-adrenergic drug dobutamine and the phosphodiestherase inhibitor milrinone are associated with increased mortality in patients with pronounced chronic and acute congestive heart failure. Levosimendan, a new inotropic drug, has shown lower mortality compared to dobutamine in patients with acute congestive heart failure. CONCLUSION: New concepts have finally emerged, including the application of old drugs such as nitrates in new (i.e., higher) dosages, as well as the novel compound levosimendan, recommended for patients with AHF and hypoperfused organs. The new ESC classification of AHF provides a valuable and long-awaited guideline to diagnose and treat this severe condition.

Acute Disease↗
PubMed2006

Monitoring platelet inhibition after clopidogrel with the VerifyNow-P2Y12(R) rapid analyzer: the VERIfy Thrombosis risk ASsessment (VERITAS) study.

INTRODUCTION: Clopidogrel inhibits platelet P2Y12 ADP receptors, while ADP, as an inductor of aggregation, stimulates both P2Y12 and P2Y1 platelet receptors. Despite a clinical loading dose routine with clopidogrel, some patients still experience coronary stent thrombosis suggesting persistent platelet activation. The VerifyNow-P2Y12 is a rapid assay that test platelet activity over 3 min and uses of the combination of ADP and prostaglandin E1 (PGE1) to directly measure the effects of clopidogrel on the P2Y12 receptor. ADP is used to maximally activate the platelets by binding to the P2Y1 and P2Y12 platelet receptors, while PGE1 is used to suppress the ADP-induced P2Y1-mediated increase in intracellular calcium levels. OBJECTIVE: The VERIfy Thrombosis risk ASsessment (VERITAS) was a prospective study designed to measure platelet response to clopidogrel therapy in subjects with multiple risk factors or history of vascular disease using this novel point-of-care assay. METHODS: 166 participants were enrolled in 4 participating sites. Data from 147 participants were analyzed after exclusion of 19 patients due to protocol violations. Platelets were assessed twice at baseline (before clopidogrel) and at 24 h post-loading 450 mg (110 participants) or 7 days after chronic clopidogrel treatment (75 mg/day) (37 patients). All participants received aspirin 81-325 mg for at least 2 days before the study enrollment. Results from the VerifyNow-P2Y12 assay are reported in P2Y12 reaction units (PRU). RESULTS: Clopidogrel therapy resulted in a mean 64.0+/-25.3% PRU reduction. No participant reached PRU inhibition below 10% of baseline. Distribution of PRU values for the VerifyNow-P2Y12 assay shows a separation from baseline to post-clopidogrel assay values with some overlap due to high inter-individual variations in response. CONCLUSIONS: VerifyNow-P2Y12 is a reliable, fast and sensitive device suitable for monitoring of platelet inhibition during clopidogrel therapy.

Adenosine Diphosphate↗
PubMed2006

Effects of escalating doses of tirofiban on platelet aggregation and major receptor expression in diabetic patients: hitting the TARGET in the TENACITY trial?

INTRODUCTION: Ongoing search for the optimal dosing regimens, and valid concerns that some GPIIb/IIIa inhibitors may cause rebound platelet activation are limiting the use of these agents in patients with acute vascular events. MATERIALS AND METHODS: We assessed the in vitro effects of preincubation with escalating (12.5-200 ng/mL) concentrations of tirofiban on platelet biomarkers in 20 diabetic patients. Platelet activity was assessed by ADP-, and collagen-induced conventional plasma aggregometry, and by whole blood flow cytometry measuring expression of PECAM-1, GPIb, GP IIb/IIIa antigen and activity, vitronectin, P-selectin, LAMP-1, GP 37, LAMP-3, activated and intact PAR-1 thrombin receptors, GPIV, and platelet-monocyte formation. All patients were treated with aspirin (at least 81 mg daily for 1 month); other antiplatelet agents were not allowed. RESULTS: Significant decrease of ADP-induced platelet aggregation was observed starting at the low 12.5 ng/mL concentration (p=0.0001), with total inhibition occurring at 50 ng/mL of tirofiban dose. Inhibition of collagen-induced platelet aggregability requires 25 ng/ml of tirofiban (p=0.002), and was complete at 100 ng/mL. Dose-dependent blockade of GP IIb/IIIa activity was observed with tirofiban concentrations over 50 ng/mL (p=0.003). Other receptors were unaffected even with the high doses of tirofiban (100-200 ng/mL). CONCLUSION: Tirofiban completely inhibits ADP- and, with the higher dose, collagen-induced platelet aggregation. Higher loading dose of tirofiban used in the ongoing TENACITY trial (100 ng/mL) may be superior with regard to clinical outcomes to the regimens used in PRISM-PLUS (25 ng/mL), or TARGET (50 ng/mL). Selective inhibition of GPIIb/IIIa activity, and lack of alternative platelet activation beyond the GP IIb/IIIa blockade may represent the therapeutic advantage of tirofiban over other agents.

Aged↗
PubMed2006

[Medical and ventilatory treatment of acute heart failure].

BACKGROUND: Traditional medical treatment of acute heart failure has remained unchanged for many years. It has been based on oxygen supplementation and mechanical ventilatory support as well as the administration of morphine, diuretics, nitrates and inotropic agents. In 2005 the European Society of Cardiology published new guidelines on diagnosis and treatment. Also, new therapies have been introduced recently, giving rise to changes in therapeutic concepts. MATERIAL AND METHOD: The article is based on these new guidelines and recent studies selected from the literature. RESULTS: Mechanical ventilatory support reduces the number of patients who require endotracheal intubation. Nitrates in higher dosages than employed today appear to be beneficial to patients with pulmonary congestion, probably because of the pronounced afterload reducing effect. Nesiritide has shown better haemodynamic effects than common nitrate dosages in patients with congestive heart failure. Tezosentan was tested in the biggest trial ever which, however, was terminated prematurely, because of futility with regard to the endpoints dyspnoea and death. Dobutamine and milrinone are associated with increased mortality in patients with pronounced chronic and acute congestive heart failure. Levosimendan has shown lower mortality compared to dobutamine in patients with acute congestive heart failure. INTERPRETATION: New concepts have finally emerged, including the application of old drugs such as nitrates in new (i.e., higher) dosages, as well as the novel compound levosimendan, and hypoperfused organs without severe hypotension. The new European Society of Cardiology classification provides a valuable and long-awaited guideline to diagnosis and treatment.

Acute Disease↗
PubMed2006

Escitalopram, but not its major metabolites, exhibits antiplatelet activity in humans.

BACKGROUND: Clinical depression has been identified as an independent risk factor for increased mortality during follow-up in patients suffered from acute coronary events, whereas increased platelet activity has been proposed as one of the mechanisms for this association. Some evidence suggests that selective serotonin reuptake inhibitors and/or their metabolites exhibit potent antiplatelet properties. METHODS: We assessed the in vitro effects of preincubation with escalating (50-200 nmol/L) concentrations of escitalopram (ESC) S-desmethyl-citalopram (S-DCT), and S-di-desmethyl-citalopram, (S-DCT) on platelet aggregation through the expression of major surface receptors using flow cytometry and quantitatively using platelet function analyzers in 20 healthy volunteers. RESULTS: Pretreatment of blood samples with ESC with ESC resulted in a significant inhibition of platelet aggregation induced by ADP (P = 0.0001) and by collagen with the highest dose (P = 0.001). Surface platelet expressions of glycoprotein Ib (CD42) (P = 0.04), lysosome associated membrane protein-3 (CD63) (P = 0.02), and GP37 (CD165) (P = 0.03) was decreased in the ESC-pretreated samples. Closure time by the Platelet Function Analyzer-100 analyzer was prolonged for the 200 nmol/L dose (P = 0.02), indicating platelet inhibition under high shear conditions. Two major metabolites of ESC, namely S-DCT and S-DDCT, did not affect platelet activity. CONCLUSION: Escitalopram, but not its metabolites, exhibited selective inhibition of human platelet properties. The direct antiplatelet effect of ESC requires further prospective or ex vivo testing to determine the possible clinical advantage of this finding.

Adult↗
PubMed2006

Bilateral simultaneous rupture of the quadriceps tendon in an adult amateur tennis player.

Bilateral simultaneous quadriceps tendon rupture is a relatively rare injury, requiring prompt diagnosis and surgical repair. It is more common in patients older than 50 years and is usually associated with underlying metabolic or inflammatory diseases. Its occurrence is very rare in healthy individuals. We report a case of bilateral quadriceps tendon rupture in a healthy young adult that occurred while he was playing tennis. This patient presented with acute knee swellings, total inability to extend the legs, and a palpable gap above the patella.

Humans↗
PubMed2005

Dipyridamole decreases protease-activated receptor and annexin-v binding on platelets of post stroke patients with aspirin nonresponsiveness.

BACKGROUND: Although controversial, the phenomenon of aspirin resistance (AR) has been correlated in some small studies with poor clinical outcomes in patients with coronary artery disease. Even less is known regarding the role of AR in the post stroke population. The reason for and the underlying mechanism of AR is unknown. We hypothesized that excessive formation of thrombin on the platelet surface may contribute to this phenomenon and assessed how dipyridamole affects multiple platelet and thrombin generation biomarkers in AR patients after ischemic stroke. METHODS: Whole blood samples from 20 post stroke AR patients were pretreated with dipyridamole, simulating the therapeutic range, and then incubated for 45 min at 37 degrees C. Platelet characteristics were assessed by aggregometry, cartridge-based analyzer, and receptor expression by flow cytometry. Markers of thrombin generation were measured in the autologous plasma by ELISA. RESULTS: Pretreatment of blood with dipyridamole resulted in 22-26% diminished expression of intact PAR-1 receptor (p=0.021 and p=0.024) and 28-31% decrease of annexin V binding (p=0.031 and p=0.02) after incubation with 2 microg/ml and 4 microg/ml of dipyridamole, respectively. Platelet aggregation and thrombin generation markers were not affected in vitro by dipyridamole. CONCLUSIONS: Dipyridamole may be capable of overcoming increased prothrombinase complex formation and be in part able to compensate for AR in patients with moderate carotid stenosis. This phenomenon may explain the clinical advantages of Aggrenox, known to reduce ischemic events in post stroke patients as proven in clinical trials, though an additional antithrombotic benefit beyond the platelet inhibition by aspirin alone.

Aged↗
PubMed2005

A critical appraisal of the phenomenon of aspirin resistance.

Aspirin is the mainstay antiplatelet treatment in patients with high risk of cardiovascular atherothrombotic events, and its beneficial effect is documented in several clinical trials. Nevertheless, the effectiveness of aspirin has been questioned by the emergence of the concept of 'aspirin resistance' (AR). This phenomenon, although lacking a precise definition, covers the fact that some patients do not exhibit the expected platelet inhibition by use of various techniques for measuring platelet function. In this critical review, we evaluate the methods used for measuring AR. We will discuss the available data regarding the prevalence and the clinical importance of the phenomenon. Finally, the potential mechanisms underlying AR are considered.

Aspirin↗
PubMed2005

Prevalence of diastolic dysfunction as a possible cause of dyspnea in the elderly.

PURPOSE: Symptoms in patients with heart failure and preserved left ventricular ejection fraction may be caused by isolated diastolic dysfunction. The purpose of this study was to assess the prevalence of diastolic dysfunction as a potential cause of dyspnea in a sample of elderly subjects, as well as of isolated diastolic dysfunction as a potential cause of dyspnea in a subgroup with a preserved left ventricular ejection fraction and normal lung function. METHODS: A total of 152 subjects with dyspnea underwent echocardiography, electrocardiography, and lung function testing. Subjects with normal lung function test results (n = 60) underwent cardiac magnetic resonance imaging, chest radiography, bicycle exercise tests, and blood tests. Left ventricular diastolic function was assessed by a variety of echocardiographic/Doppler techniques. RESULTS: Of 129 subjects with dyspnea, 81 (63%) had signs of lung disease or 'obvious' cardiac disease. In the remaining 48 subjects, 32 (67%) had a potential cardiac/noncardiac cause of dyspnea. In all subjects with dyspnea, 1% to 11% had diastolic dysfunction, and in the 48 remaining subjects, 0% to 10% had isolated diastolic dysfunction, depending on the definition used. CONCLUSION: The frequency of diastolic dysfunction was low in the sample of elderly subjects with dyspnea as well as in the subgroup of persons with no signs of lung disease, left ventricular systolic dysfunction, atrial fibrillation, or valvular heart disease. Diastolic dysfunction was infrequent as a possible cause of dyspnea, and coexisting potential causes of dyspnea were often present.

Aged↗
PubMed2005

[Clinical and genetic aspects of congenital insensitivity to pain with anhidrosis].

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare autosomal recessive genetic disease, which is characterized by recurrent episodes of fever, anhidrosis, self mutilation, absence of reaction to noxious stimuli, prolonged healing times and mental retardation. The absence of pain sensation combined with mental retardation predisposes the children to recurrent wound infections and deep ulcers that heal at a slower pace than seen in healthy people. The anomalous pain is due to the absence of dorsal root ganglia that are responsible for pain sensation and absence of afferent neurons activated by tissue damaging stimuli. Nerve Growth Factor (NGF) is a growth factor that supports the survival of nociceptive sensory and autonomic sympathetic neurons. Neurotrophin Tyrosine Receptor (NTRK1) encodes a receptor tyrosine kinase that is activated in response to NGF. NTRK1 mutations have been found in mice that presented with clinical signs similar to CIPA, subsequently CIPA patients have been examined for these mutations as well. Currently, 37 different mutations at the NTRK1 are known which cause CIPA. The above syndrome is so rare that until the year 2000 only 84 cases have been reported, not including 28 known cases of CIPA patients from Israeli Bedouins. Since no cure is available, prenatal screening, as conducted in our institution, is the only available preventive option to avoid the birth of an affected child.

Child↗
PubMed2005

[Emergency room consultation policy prevents surgery delay in elderly patients with hip fractures].

Clinical guidelines for the management of hip fractures strongly emphasize the critical role of early surgery as a major factor affecting better health outcomes. Shortening the time from admission to pre-operative consultation by bringing the consultants to the emergency room, before patient admission to the orthopedic ward, is am efficient cost effective hospital policy that enables adherence to guideline recommendations. Early pre-operative specialist consultation is an efficient cost effective policy for preventing delay of surgery following hip fracture in the elderly.

Aged↗
PubMed2004

Magnitude and time course of platelet inhibition with Aggrenox and Aspirin in patients after ischemic stroke: the AGgrenox versus Aspirin Therapy Evaluation (AGATE) trial.

The European Stroke Prevention Study showed greater stroke prevention for Aggrenox than either for aspirin or dipyridamole alone. To test whether Aggrenox has superior antiplatelet properties to aspirin alone we conducted the AGgrenox versus Aspirin Therapy Evaluation (AGATE) trial. Forty patients with prior ischemic stroke not taking aspirin for at least 30 days were randomized to Aggrenox (2 pills/daily) or aspirin (81 mg plus matching placebo/daily) for 30 days. Platelet function was assessed at baseline, 24 h, and days 3, 7, 15, and 30 by aggregometry, flow cytometry and cartridge-based analyzers. Both Aggrenox and aspirin provided fast and sustained platelet inhibition. Aggrenox(R), however, especially after 15 days, showed significant prolongation of the closure time (P=0.04), diminished expression of platelet/endothelial cell adhesion molecule-1 (PECAM-1) (P=0.01), glycoprotein IIb (GPIIb) antigen (P=0.02), and GPIIb/IIIa activity (P=0.01) by PAC-1 C antibody, CD63 (P=0.03), as well as inhibition of Protease Activated Receptors (PAR-1) associated with intact (SPAN12, P=0.01) and cleaved (WEDE15, P=0.01) thrombin receptors as compared with aspirin. Surprisingly, GPIb expression increased, especially after aspirin. In the randomized trial of small sample size, aspirin and Aggrenox produced fast and sustained platelet inhibition. In 25 of 90 direct comparisons, Aggrenox was superior to aspirin, whereas in 4 of 90, aspirin was superior to Aggrenox. In 61 of 90 direct comparisons, aspirin and Aggrenox were equivalent. Aggrenox was associated with a profound reduction of PAR-1 receptors, an observation that may be related to the greater clinical benefit of Aggrenox compared with Aspirin in preventing recurrent stroke.

Aged↗