جستجوی مقالات مرتبط با کلیدواژه « کلوپیدوگرل » در نشریات گروه « پزشکی »

Despite the widespread use of clopidogrel as a prodrug in a wide range of patients, the researchers found that the drug couldn't have sufficient antiplatelet effects at a usual dose in three to forty percent of patients. So on, measuring clopidogrel active metabolite concentration is seems necessary to evaluate the effects of this drug in each patient.

Due to the importance of determining clopidogrel active metabolite plasma level, in this article, we reviewed and compared all the analysis methods for that which could affects on correct pharmacokinetic evaluation of clopidogrel and thus play an important role in prescribing the appropriate dose of that in each individual therapy. Despite numerous reports of the clopidogrel analysis method, only thirteen studies have been published to analyzing the concentration of clopidogrel active metabolite in a biological matrices. As a result of the very low concentration and short half-life of the clopidogrel active metabolite in the biological matrice, the method used for determining itʹs concentration profile should be able to measure values in picogram per millilitre scale.

According to the complete summary of the analyzing methods, employing advanced device analysis systems such as UHPLC lead to much more accurate separation and quantification of analytes. Also, employing the MS / MS detector adding the possibility of measuring the clopidogrel plasma level in the same matrices.

Clopidogrel is an effective anti-platelet drug that is commonly prescribed for patients with atherosclerotic coronary and peripheral vascular diseases, especially after angioplasty and coronary artery bypass graft surgery. Even though this drug seems safe, there are case reports of important side effects with its use.

The patient was 67 years old male admitted with a diagnosis of inferior myocardial infarction who underwent angioplasty on RCA with a drug-eluting stent and was discharged with an uneventful course from hospital with medical treatment, including Clopidogrel. The patient came back to the clinic 30 days later with icter, nausea and loss of appetite. The lab data showed: Bilirubin (total= 5, direct=4), ALT=220, AST=100, Gama GT=830, Alk.phop=445. Virologic and imaging studies were normal. With a possible diagnosis of drug-induced hepatic injury all possible Prescribed drugs were held stepwise but bilirubin and the patient’s symptoms did not relieve until Clopidogrel has been changed. After 10 days bilirubin and his symptom relieved.

Clopidogrel is a common and partially safe drug, but it may cause hepatic injury. Considering Clopidogrel side effects and its interactions seem necessary for patient management.

Clopidogrel is one of the most commonly prescribed drugs to prevent ischemic events following coronary syndromes or stent placement. The objective of this study was to evaluate the prevalence of the cytochrome P450 (CYP450) 2C19 enzyme (CYP2C19) genotypes in the Iranian population. CYP2C19 (*1/*2/*3) variants were analyzed using Polymerase Chain Reaction-Restriction Length Polymorphism (PCR–RFLP) assays in a representative sample of 154 Iranian patients with ischemic heart disease in Peyvand Laboratory. In this study, out of 154 Iranian patients the frequency rates of CYP2C19 *2 were 36 (23.4%) in heterozygous and 6 (3.9%) in homozygous forms; 112 (72.7%) patients had the normal genotype. FDA recommendations are more useful to be practiced in our country than other countries. Physicians should identify patients and advise them to consider other antiplatelet medications or alternative dosing strategies in poor metabolizers.

Platelet activation and aggregation plays an essential role in the for-mation of coronary artery thrombosis. Nowadays, the Clopidogrel is administered oral-ly as an inhibitor of platelet aggregation. Due to the high price of the original brand of Clopidogrel (Plavix), an Iranian brand of Clopidogrel (Osvix) has been produced. This study was conducted to evaluate the effectiveness, side effects and acceptability of lo-cally available brand of Osvix as anti platelet tablet in coronary artery bypass grafting patients in comparison to the original brand (Plavix) by means of platelet aggregation indexes. This clinical study, was conducted at Heart Center of Ekbatan university Hospital in Hamadan in October 2011 to May 2012. In this study 80 patients undergo-ing coronary artery bypass grafting (CABG) were participated in two independent treatment groups. One group used the Iranian brand of Osvix and other one used the original brand (Plavix) as an inhibitor of platelet aggregation. To evaluate the effective-ness of these two in-inhibiting platelets regimens, blood samples were taken from the patients and platelet aggregation test was performed using Helena Biosiences Europe, PACKS4 aggrigometry system (made in France). Mean platelet-rich plasma amount for the Osvix and Plavix treatment group was 236.260 and 153.290 plt/µl respectively. Results showed a statistically significant difference in the rate of platelet-rich plasma by two above mentioned treatment groups. There was no observed statistical difference in side effects of two studied treatment groups. It must be noted that the effectiveness of Plavix tablet regimen as a platelet aggregation inhibitor in patients undergoing CABG was higher than the Osvix tablet treatment regimen. This study showed the Iranian brand of Clopidogrel (Osvix) is significantly different from the original brand (Plavix) in terms of performance factors in preventing platelet aggregation in patients undergoing coronary artery bypass grafting.

Clopidogrel is an adenosine-5' diphosphate (ADP) receptor antagonist that eventually inhibits platelet aggregation. It is used concomitantly with percutaneous coronary interventions and in patients with acute coronary diseases. This study was conducted to determine the effects of preoperative clopidogrel administration on perioperative blood loss and transfusion requirements in patients undergoing coronary artery bypass graft (CABG) surgery. For 100 patients who underwent nonurgent first-time coronary artery bypass grafting surgery participated in this study. clopidogrel was discontinued in 2, 3, 5-6 or 7-8 days before surgery. A cell salvage device was used during surgery and salvaged blood was recorded. After surgery, chest tube output and need for blood transfusion were measured and recorded. Patient's mean age was 61.7 ± 8.0 years (range: 50 to 77). There was a reverse relation between the time clopidogrel had been discontinued and blood loss and need for transfusion of packed cell and blood products during and after surgery (P < 0.05 for all). Preoperative clopidogrel administration increases perioperative blood loss and need for blood transfusion in patients undergoing coronary artery bypass grafting surgery.

Platelets have a crucial role in homeostasis and thrombosis. Their haemostatic role is to prevent from bleeding after activation in the platelet aggregation pathway. In pathologic cases, they contribute to atherothrombosis. Antiplatelet drugs inhibit platelet aggregation so they are used successfully in treatment courses. Clopidogrel, an antiplatelet drug, is an ADP analogue. It inhibits ADP coupling with its receptor and prevents atherothrombosis. Despite its great success, some patients do not display an adequate antiplatelet response due to genetic resistance. Genetic investigations have displayed CYP2C19 polymorphism as the most prevalence factor of genetic resistance. Use of higher doses of Clopidogrel, combined antiplatelet therapies or new potent drugs is a potential alternative strategy.

In patients who undergo coronary angioplasty, Clopidogrel resistance is accompanied with increased risk of cardiovascular events (unstable angina, recurrent MI, death, etc). In different studies resistance to Clopidogrel has been reported to be up to 30%. Identification of these patients and determining the contributing factors can help us to reduce cardiovascular events. This cross-sectional study was carried out on candidates of elective percutaneous coronary intervention (PCI) in Shahid Modarres Hospital. Resistance to Clopidogrel was evaluated by platelet aggregometry in platelet-rich-plasma (PRP) using a routine aggregometer (Helena Biosciences Europe). The platelet aggregation was measured before and after exposure to 20 µ mol ADP as a reagent. Contributing factors such as age, gender, metabolic factors and medications were examined by Chi-square test. This study was run on 90 candidates for elective PCI. Their mean age was 62.6±10.2 years and 52.2% were male. 20% were semi-responder and 7.8% was non-responder. Gender, hypertension, obesity, using angiotensin-converting enzyme inhibitors and calcium channel blockers did not have any role in Clopidogrel resistance, but diabetes, hyperlipidemia, using beta blockers and statins were more common in Clopidogrel resistant patients (p<0.005). ‍ Considering both non-responders and semi-responders, prevalence of resistance to Clopidogrel was 27.8%, so we must be worried about it. Further larger studies should be designed to determine and manage the contributing factors.

Patients who have transient ischemic attack (TIA) or ischemic stroke are at a high risk of having a first or recurrent stroke. Secondary prevention includes antithrombotic therapy, treatment of risk factors, and interventional treatment of carotid stenosis. The merits of antiplatelet therapy with different protocols in primary and secondary stroke prevention have been demonstrated across numerous trials which lead to somewhat contradictory findings. Our objective was to compare the effects of aspirin, clopidogrel, and clopidogrel plus aspirin in the prevention of recurrent stroke. Ninety-two patients with TIA or minor ischemic stroke were randomly assigned in three groups: Group A (aspirin, 80-100 mg/day 29 patients), group B (clopidogrel, 75 mg/day 31 patients) and group C (clopidogrel 75 mg/day plus aspirin 80-100 mg/day 32 patients). All patients were followed for a period of 18 months. Rather than demographic data, the number of new attacks and the time it occurs were recorded for each patient. Kaplan-Meier analysis was performed to compare the median time to stroke outcome in each group. The patients were 53 (57.6%) male and 39 (42.4%) female with the mean age of 65.47(SD=8.36) year which was not significantly different in three groups of study (P>0.05). After 18 months of follow-up, the mortality rate was 13.8%, none and 3.1% in groups A, B and C, respectively. The mean number of attacks was significantly lower in group C [0.63(standard deviation (SD)=0.49)] than groups A [1.59(SD=0.95)] and B [0.81(SD=0.65)] (P<0.001). Moreover, the mean time to stroke outcome was significantly longer in group C [16.12(Standard error (SE)=0.57) month] than groups A [6.76(SE=1.21) month] and B [13.71(SD=1.02) month] (Log rank P<0.001). Antiplatelet therapy is effective in secondary stroke prevention. Current recommendations are applied in clinical�practice, but great variability between different centers remains. Our results showed that aspirin combined use with clopidogrel have better efficacy and decreased rate of recurrence in patients with TIA or minor ischemic stroke in this single-center study.