Percutaneous Coronary Interventions and Antiplatelet Therapy in the Perioperative Period

The Management of Antiplatelet Therapy in Patients With Coronary Stents Undergoing Noncardiac Surgery

Whereas the development of coronary stents has been a major breakthrough in the treatment of coronary artery disease, stent thrombosis, associated with myocardial infarction and death, has introduced a new challenge in the care of patients with coronary stents undergoing noncardiac surgery. This review presents the authors’ recommendations regarding the optimal management of such patients. Elective surgery should be postponed for at least 6 weeks and optimally 3 months for a bare-metal stent and at least 1 year for a drug-eluting stent. On the other hand, managing a patient undergoing non-elective surgery is more difficult and necessitates a case-by-case assessment of bleeding risk versus thrombotic risk based on patient comorbidities, type of stents present, details of the coronary intervention, and type of surgical procedure. Patients with a risk of bleeding that outweighs the risk of stent thrombosis should discontinue at least clopidogrel, whereas all other patients should continue dual antiplatelet therapy throughout the perioperative period.

Progress in platelet medicine: focus on stent thrombosis and drug resistance

The outcome importance of coronary stent thrombosis has mandated the careful management of these devices and their associated platelet blockade during the perioperative period. Recent trials have highlighted the catastrophic outcomes after stent thrombosis. The maintenance of clinically effective platelet blockade not only is essential to prevent stent thrombosis but also to optimize outcome in the integrated management of acute coronary syndromes. Dual antiplatelet blockade with aspirin and clopidogrel must balance the risks of ischemia and bleeding in patients with acute coronary syndromes, especially in the subset who require urgent surgical coronary revascularization. Platelet resistance to thienopyridines such as clopidogrel and prasugrel may be a significant risk factor for adverse cardiovascular outcomes. This phenomenon is detectable by point-of-care assays although standardized definitions and standardized testing batteries have yet to be formulated. The determinants of platelet resistance to thienopyridine therapy include genetic polymorphisms (especially related to hepatic drug metabolism) and drug interactions (especially the proton pump inhibitors). Novel platelet blockers are currently in late clinical development and will likely induce more consistent platelet blockade because of pharmacokinetic advantages including the lack of hepatic metabolism for activation. These agents will likely supersede clopidogrel and prasugrel if randomized trials show superior efficacy and clinical safety.

[Perioperative discontinuation of antiplatelet therapy of patients with coronary stents. Reevaluating the risks]

According to the present guidelines, patients with coronary stents are to be treated with dual antiplatelet therapy. In case surgery is needed, the risk of a fatal stent thrombosis by withdrawing antithrombotics needs to be balanced in each individual case against the risk of haemorrhagic complications on continued antiplatelet medication. We present a case of fatal stent thrombosis and discuss the current evidence regarding perioperative continuation and interruption of antiplatelet therapy for this patient population. In summary the haemorrhagic risk with acetylsalicylic acid for secondary prevention seems very low, and it should be discontinued only in selected cases. Continued dual anticoagulation concepts are also discussed.