Introduction: The concept of clopidogrel resistance, first described in biology is being strengthened by recent data from clinical epidemiology. The cardiologists have been sensitized to this concept because of its po...Introduction: The concept of clopidogrel resistance, first described in biology is being strengthened by recent data from clinical epidemiology. The cardiologists have been sensitized to this concept because of its possible involvement in the occurrence of coronary stent thrombosis. Purpose of the study: The purpose of this study was to investigate the genetic variant of the gene CYP 2C19 inour population and to assess the involvement of this genetic profile in the occurrence of major cardiovascular events (MACE) during the follow-up period. Methods: Our prospective study was conducted between May 2009 and September 2010 including 100 patients admitted to the cardiology department for percutaneous coronary stenting. The patients were divided into 2 groups: those with at least one CYP2C19*2 allele (*2 carriers) and non-carriers. Results: The mean age of our patients was 56.7 years ± 10, 5. No remarkable differences in the baseline characteristics were noted between the two groups. The prevalence of CYP2C19*2 allele in our population was 11.5%. Hospital mortality was estimated at 3%. No statistically significant differences were noted between the two groups regarding the occurrence of intra hospital MACE. The mean follow up was 7.5 ± 4.87 months for the entire study population. The rate of MACE during the follow-up of patients receiving clopidogrel was 8.2% throughout the study population: 5.3% in the *2 non-carriers versus 18.2% in the *2 carriers with a statistically significant difference (p = 0.075) at the risk of error of 10%. Concerning the occurrence of stent thrombosis, there was no significant statistical difference between the two study groups. Conclusion: From these results it is suggested that CYP2C19*2 polymorphism is associated with increase in the occurrence of MACE among Tunisian patients receiving clopidogrel. A larger study is needed to assess the role of genotyping in the evaluation of the phenomenon of clopidogrel resistance.展开更多
Background Dual anti-platelet treatment with aspirin and clopidogrel is established foundation for patients undergoing percutaneous coronary intervention （PCI） to prevent thrombotic events. The present study was con...Background Dual anti-platelet treatment with aspirin and clopidogrel is established foundation for patients undergoing percutaneous coronary intervention （PCI） to prevent thrombotic events. The present study was conducted to examine whether the CYP2C19 681G〉A polymorphism and cigarette smoking had independent or interactive effect on response to clopidogrel. Methods Among 722 Chinese Han patients undergoing elective coronary stent placement due to stable angina pectoris, a loading dose of 300 mg clopidogrel was given to all patients and a daily maintenance dose of 75 mg for a minimum of 12 months. CYP2C19 681G〉A polymorphism was genotyped. The platelet reactivity was measured by light transmittance aggregometry （LTA） with 5 lumol/L adenosine diphosphate （ADP） induced. The poor response was defined as 10% or less absolute difference between aggregation at baseline and 24 hours after loading dose of clopidogrel. Results The results showed that the poor-response to clopidogrel was presented in 105 patients （14.5%）. Overall, the genotype GA/AA carriers were likely to be poor-responsive cases （19.6% vs. 11.0%, P=-0.001） with odds ratio （OF/） of 1.971 （95% CI： 1.296-2.998, P=0.002）, compared with the GG homozygotes. Meanwhile, compared with nonsmokers, the smokers showed lower rate of poor-response （10.9% vs. 17.3%, P=0.015） with OR of 0.582 （95% C/： 0.374-0.904, P=-0.016）. The smokers with GG genotype had the lowest risk with OR of 0.487 （95% CI： 0.246-0.961, P=-0.038） while nonsmokers with GA/AA genotype had the highest risk of poor-response with OR of 1.823 （95% C/： 1.083-3.068, P=0.024）, compared with nonsmokers with GG genotype. However, there was no significant interaction between genotype and smoking. Conclusion Our study indicated that both CYP2C19 polymorphism and smoking independently affected response to clopidogrel.展开更多
文摘Introduction: The concept of clopidogrel resistance, first described in biology is being strengthened by recent data from clinical epidemiology. The cardiologists have been sensitized to this concept because of its possible involvement in the occurrence of coronary stent thrombosis. Purpose of the study: The purpose of this study was to investigate the genetic variant of the gene CYP 2C19 inour population and to assess the involvement of this genetic profile in the occurrence of major cardiovascular events (MACE) during the follow-up period. Methods: Our prospective study was conducted between May 2009 and September 2010 including 100 patients admitted to the cardiology department for percutaneous coronary stenting. The patients were divided into 2 groups: those with at least one CYP2C19*2 allele (*2 carriers) and non-carriers. Results: The mean age of our patients was 56.7 years ± 10, 5. No remarkable differences in the baseline characteristics were noted between the two groups. The prevalence of CYP2C19*2 allele in our population was 11.5%. Hospital mortality was estimated at 3%. No statistically significant differences were noted between the two groups regarding the occurrence of intra hospital MACE. The mean follow up was 7.5 ± 4.87 months for the entire study population. The rate of MACE during the follow-up of patients receiving clopidogrel was 8.2% throughout the study population: 5.3% in the *2 non-carriers versus 18.2% in the *2 carriers with a statistically significant difference (p = 0.075) at the risk of error of 10%. Concerning the occurrence of stent thrombosis, there was no significant statistical difference between the two study groups. Conclusion: From these results it is suggested that CYP2C19*2 polymorphism is associated with increase in the occurrence of MACE among Tunisian patients receiving clopidogrel. A larger study is needed to assess the role of genotyping in the evaluation of the phenomenon of clopidogrel resistance.
文摘Background Dual anti-platelet treatment with aspirin and clopidogrel is established foundation for patients undergoing percutaneous coronary intervention （PCI） to prevent thrombotic events. The present study was conducted to examine whether the CYP2C19 681G〉A polymorphism and cigarette smoking had independent or interactive effect on response to clopidogrel. Methods Among 722 Chinese Han patients undergoing elective coronary stent placement due to stable angina pectoris, a loading dose of 300 mg clopidogrel was given to all patients and a daily maintenance dose of 75 mg for a minimum of 12 months. CYP2C19 681G〉A polymorphism was genotyped. The platelet reactivity was measured by light transmittance aggregometry （LTA） with 5 lumol/L adenosine diphosphate （ADP） induced. The poor response was defined as 10% or less absolute difference between aggregation at baseline and 24 hours after loading dose of clopidogrel. Results The results showed that the poor-response to clopidogrel was presented in 105 patients （14.5%）. Overall, the genotype GA/AA carriers were likely to be poor-responsive cases （19.6% vs. 11.0%, P=-0.001） with odds ratio （OF/） of 1.971 （95% CI： 1.296-2.998, P=0.002）, compared with the GG homozygotes. Meanwhile, compared with nonsmokers, the smokers showed lower rate of poor-response （10.9% vs. 17.3%, P=0.015） with OR of 0.582 （95% C/： 0.374-0.904, P=-0.016）. The smokers with GG genotype had the lowest risk with OR of 0.487 （95% CI： 0.246-0.961, P=-0.038） while nonsmokers with GA/AA genotype had the highest risk of poor-response with OR of 1.823 （95% C/： 1.083-3.068, P=0.024）, compared with nonsmokers with GG genotype. However, there was no significant interaction between genotype and smoking. Conclusion Our study indicated that both CYP2C19 polymorphism and smoking independently affected response to clopidogrel.
