Does percutaneous coronary stent implantation increase platelet reactivity?

High platelet reactivity (PR) values on treatment with clopidogrel are associated with an increased rate of thrombotic events after a percutaneous coronary intervention (PCI). However, we do not know the optimal timing of the performance of the PR measurements. Platelets might be activated during a PCI, which means that the timing of PR measurements, before or after PCI, could influence the outcome. In turn, this could lead to misinterpretation of the patient's response to antiplatelet therapy and a less accurate prediction of the patient's risk of thrombotic events during follow-up. We aimed to evaluate the effect of stent implantation on PR in patients with and without acute coronary syndromes who undergo PCI to assess the optimal timing of PR measurements. A systematic literature search was performed and the results are summarized in this review.