High post-clopidogrel platelet reactivity assessed by a point-of-care assay predicts long-term clinical outcomes in patients with ST-segment elevation myocardial infarction who underwent primary coronary stenting.
BACKGROUND
Recent studies have shown that post-clopidogrel high platelet reactivity (HPR), assessed by a point-of-care assay, is associated with a higher risk of adverse events after percutaneous coronary intervention (PCI). We assessed the clinical impact of HPR by the VerifyNow P2Y12 point-of-care assay in 181 patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary PCI with drug-eluting stents (DES) at 3 hospitals.


METHODS
The primary endpoint of the study was the 12-month major adverse cardiovascular events (MACE), which comprised cardiovascular death, nonfatal MI and ischemic stroke. All patients received a single loading dose of 600 mg clopidogrel and 300 mg aspirin followed by a daily maintenance dose of 75 mg clopidogrel and 100mg aspirin.


RESULTS
A P2Y12 reaction unit (PRU) ≥ 282 (AUC 0.719, 95% CI 0.588-0.851, p=0.004, sensitivity 68.8%, specificity 73.8%) was the optimal cut-off value in predicting 12-month MACE by receiver operating characteristic curve analysis. Occurrence of MACE was significantly more frequent in patients with HPR (PRU ≥ 282) compared to patients without HPR (20.4% vs. 3.9%, HR 6.24, 95% CI 2.05-18.99, p=0.001). By multivariate analysis, HPR (HR 3.84, 95% CI 1.17-12.58, p=0.026) and elderly patients above 80 years of age (HR: 8.13, 95% CI 1.79-37.03, p=0.007) were found to be the significant predictors of 12-month MACE. The MACE-free survival rate was significantly lower in patients with HPR compared to patients without HPR (p<0.001).


CONCLUSIONS
HPR assessed by a point-of-care assay was able to predict 12-month MACE in patients with STEMI who underwent primary PCI with DES.
Division of Cardiology, Department of Internal Medicine, Inje University College of Medicine, Cardiovascular Research Institute, Busan Paik Hospital, Busan, South Korea.
Han-Young
HY
Jin
Tae-Hyun
TH
Yang
Doo-Il
DI
Kim
Sang-Ryul
SR
Chung
Jeong-Sook
JS
Seo
Jae-Sik
JS
Jang
Dae-Kyeong
DK
Kim
Dong-Kie
DK
Kim
Ki-Hun
KH
Kim
Sang-Hoon
SH
Seol
Chang-Wook
CW
Nam
Seung-Ho
SH
Hur
Woong
W
Kim
Jong-Seon
JS
Park
Young-Jo
YJ
Kim
Dong-Soo
DS
Kim
D000368:Aged; D001241:Aspirin / Q000008:administration & dosage; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D000077144:Clopidogrel; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000175:diagnosis / Q000628:therapy*; D062645:Percutaneous Coronary Intervention / Q000379:methods* / Q000639:trends; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D019095:Point-of-Care Systems / Q000639:trends; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015607:Stents; D013988:Ticlopidine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D016896:Treatment Outcome
D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D013988:Ticlopidine; D001241:Aspirin