Author + information
- Elad Asher,
- Perry Anarado,
- Myttle Mayuga,
- Martin Bradley,
- Ka Chun Alan Chan,
- Isidore Okere,
- Darwin Jeyaraj,
- Daniel I. Simon and
- Tom Lassar
To assess whether Accumetrix VerifyNow P2Y12 testing directed anti-platelet therapy after acute coronary syndromes (ACS) percutaneous coronary intervention (PCI) in a real world setting, could affect outcomes.
Multiple trials suggest that high residual on-treatment platelet reactivity (HRPR) [Platelet Reactivity Units (PRU) ≥230] increases the incidence of major adverse cardiac events: death, myocardial infarction, target vessel revascularization and stent thrombosis (MACE). Data on routine real world testing of ACS patients is lacking.
371 ACS patients had PCI and platelet function testing after initial background aspirin and ≥ 600 mg of clopidogrel. For PRU at 12-24 hours < 230, maintenance 325 mg/day of aspirin and 75 or 150 mg/day of clopidogrel for 1 week then 75 mg/day were continued unless followup testing at 1-3 weeks demonstrated HRPR. Most patients with initial HRPR were switched to prasugrel or ticagrelor with no further testing, as hyporesponse is rare; or clopidogrel 150 mg/day with repeat testing at 1-3 weeks. Continued HRPR on clopidogrel usually drove switching to prasugrel or ticagrelor unless contraindicated.
There were 148 (40%) HRPR and 223 (60%) responders patients. MACE was similar between the two groups [5/148 (3.4%) vs. 6/223 (2.7%), respectively, p=0.76]. Even after subdividing ACS to unstable angina (UA) and Non ST elevation MI (NSTEMI) vs. ST elevation MI (STEMI) MACE was similar for HRPR and responders [4/113 (3.5%) vs. 6/163 (3.7%), respectively, p=NS, for UA/NSTEMI and 1/35 (2.8%) vs. 2/60 (3.3%), respectively, p=NS, for STEMI]. The 30 day incidence of stent thrombosis was only 1 in the HRPR group and was related to medication noncompliance.
Adjusting anti-platelet therapy for ACS patients on the basis of VerifyNow testing results in low and equivalent MACE at 30 days after PCI, for initial anti-platelet responders and HRPR patients switched to more effective therapy.
- 2013 American College of Cardiology Foundation