The value of high on-treatment platelet reactivity and real time pcr test for cyp2c19 variants for saudi patients with acute coronary syndrome

Background Clopidogrel has been known for its variable response due to genetic variations. Several researchers have suggested genetic testing and or platelet function test (PFT) routinely. Aim: To find out the value of genotyping and PFT in Saudi patient with acute coronary syndrome (ACS). Methodology Thirty Saudipatients with ACS underwent coronary angioplasty with drug eluting stents wereconsecutively enrolled. Patients received clopidogrel as per usual dose of 300mgloading and 75mg per day as maintenance dose. Pre-procedure arterial bloodsample was taken from every patient for assessment of high on treatment PFT (Verify Now P2Y12 point-of-care assay).Ten patients underwent Real time PCR test for CYP2C19 variants. In hospital clinical events (one month F/U) were monitored for all patients. Results The mean baseline platelet reactivity was 196 ± 58u (107:341).The mean P2Y12 reaction units (PRU) was found 188 ± 61u (88:362). High platelet reactivity (HPR) on clopidogrel defined as PRU more than 240 was found in 5 patients (17%); whereas, the mean percent of platelets inhibition was 12 %(range 0%: 48%). Analysis of CYP2C19 variants revealed 8 patients have mild variant 1/1 and 2 patients have moderate resistant variant 2/2. We couldn’t detect allele 3 probably as our sample was small. No in-hospitalclinical events were encountered, including death,MI, stroke or repeatedrevascularization. Conclusion We found a little impact of the usual dose of clopidogrel on the percentage of platelet inhibition. Twenty percent of those underwent CYP2C19 analysis showed modest resistant gene. Irrespectivly weencountered no in-hospital events in our patients.