AIM OF THE STUDY: To establish the relationship between CYP2C19 genotype, clopidogrel responsiveness and 1-year MACE.
MATERIALS & METHODS: Aspirin/clopidogrel responses were assessed with Multiplate Analyzer and CYP2C19*2 allele by SpartanRx.
RESULTS: A total of 42.0% carried ≥1 CYP2C19*2 allele. Prevalences of aspirin and clopidogrel high on-treatment platelet reactivity (HPR; local cutoffs: 300 AU*min for aspirin and 600 AU*min for clopidogrel) were 11.5% and 19.8% respectively. In multivariate ana-lysis, clopidogrel HPR was found to be an independent predictor for 1-year MACE (adj HR: 3.48, p = 0.022 ).
CONCLUSION: Having clopidogrel HPR could be a potentially modifiable risk factor guided by phenotyping.
OBJECTIVE: This study aimed to investigate the prevalence and impact of CYP2C19*2, *3 and *17 genotypes on clopidogrel responsiveness in a multiethnic Malaysian population planned for percutaneous coronary intervention.
SETTING: Between October 2010 and March 2011, a total of 118 consecutive patients planned for percutaneous coronary intervention were enrolled in Sarawak General Hospital, Borneo. All patients received at least 75 mg aspirin daily for at least 2 days and 75 mg clopidogrel daily for at least 4 days prior to angiography.
METHOD: Genotyping for CYP2C19*2 (rs4244285, 681G > A), *3 (rs4986893, 636G > A) and *17 (rs11188072, -3402C > T) alleles were performed by polymerase chain reaction-restriction fragment linked polymorphism method. Whole blood ADP-induced platelet aggregation was assessed with multiple electrode platelet aggregometry (MEA) using the Multiplate Analyzer.
MAIN OUTCOME MEASURES: The distribution of CYP2C19*2, *3 and *17 among different ethnic groups and the association between genotype, clopidogrel responsiveness and clinical outcome were the main outcome measures.
RESULTS: The highest prevalence of poor metabolisers (carriers of at least one copy of the *2 or *3 allele) was among the Chinese (53.7 %), followed by the Malays (26.9 %), Ibans (16.4 %) and other races (3.0 %). Poor metabolisers (PMs) had the highest mean MEA (303.6 AU*min), followed by normal metabolisers (NMs) with 270.5 AU*min and extensive metabolisers (EMs) with 264.1 AU*min (p = 0.518). Among poor responders to clopidogrel, 65.2 % were PMs and NMs, respectively, whereas none were EMs (p = 0.350). Two cardiac-related deaths were reported.
CONCLUSION: There was a diverse inter-ethnic difference in the distribution of CYP2C19 polymorphism. The findings of this study echo that of other studies where genotype appears to have a limited impact on clopidogrel responsiveness and clinical outcome in low-risk patients.
MATERIALS AND METHODS: We report 20 consecutive patients with end-stage renal failure (ESRF) who had central vein occlusion and were not amenable to endovascular intervention. They underwent extra-anatomical vein to vein surgical bypass. The axillary and iliac or femoral veins were approached via infraclavicular and extraperitoneal groin incisions respectively. In all the patients, an externally supported 6 or 8 mm polytetrafluoroethylene (PTFE) graft was used as a conduit and was tunnelled extra-anatomical. All patients had double antiplatelet (Aspirin and Clopidogrel) therapy post-operatively.
RESULTS: Substantial improvement in the facial, neck and upper limb swelling was noticed following this diversion surgery. The vein to vein bypass was patent at 12 months in 10 out of 20 patients. Graft infection occurred in two (10%) cases. Re-thrombectomy or assisted patency procedure (stent/plasty) was done in four (20%) cases. The patients with preoperative fistula flow rate of more than 1500 ml/min and post-operative graft flow rate of more than a 1000 ml/min were patent at 12 months (P=0.025 and p=0.034 respectively).
CONCLUSION: Axillary to iliac/femoral vein bypass can salvage functioning ipsilateral fistula threatened by occluded upper central vein.