Coronary stents and non-cardiac surgery: to bridge or not to bridge?

Abstract

Haemost 2015; 114: 423-431. Patients with coronary stents need antiplatelet therapy to reduce the risk of stent thrombosis. The standard therapy is lifelong low-dose aspirin with supplementary P2Y12-inhibitor treatment during the first months. In patients who have suffered from an acute coronary syndrome (ACS), the P2Y12-inhibitor is usually given for 12 months (1–3). In these patients, the new and stronger P2Y12-inhibitors ticagrelor or prasugrel are preferred over clopidogel, unless the patient is at high risk of bleeding (1–3). In stable coronary patients undergoing elective stenting, clopidogrel is used (3), and the recommended treatment duration depends on the type of stent: bare metal stents 1–3 months, first-generation drug-eluting stents (DES) 12 months and second-generation DES usually six months (3). Earlier cessation of dual antiplatelet therapy (DAPT) carries a high risk for stent thrombosis (4, 5). A need for elective or acute surgery for cardiac or non-cardiac disease is not uncommon in patients with recent stent implantation (6–8). This clearly puts the clinician in a difficult dilemma as an operation is associated with bleeding: should surgery be performed during dual or mono antiplatelet therapy or maybe even without any antiplatelet therapy at all? As the risk of stent thrombosis is highest in the weeks after stent implantation, postponing the operation is an attractive option. Surgery in patients on low-dose aspirin is associated with increased risk of bleeding (9), and bleeding rates are higher when surgery is performed on DAPT (10). Bleeding is a particular problem in some surgical scenarios such as spinal and brain surgery, but also in less extensive procedures such as percutaneous organ biopsies, where neither compression nor direct surgical haemostasis can be performed, are major challenges. In these situations, the surgeon may prefer to stop all antithrombotic medication, whereas individualised perioperative management of antiplatelet therapy guided by platelet function testing might be possible in selected patients undergoing elective surgery (11). Difficult dilemmas should be discussed at a multidisciplinary team conference with participation of a cardiologist, a surgeon, an anaesthesiologist and sometimes also other experts (12). As mentioned, postponing surgery in patients on dual antiplatelets is advised if at all possible. Indeed, DES are most often used and the duration of DAPT is usually for 6–12 months, although with newer generation DES, it might be possible to shorten the time interval to three months (3). In life-threatening acute conditions, surgery may have to be performed on ongoing/uninterrupted DAPT. In other cases (e.g. operations for malignancies), surgery cannot be postponed for several months and given that these cases are particularly challenging they would need to be discussed in the multidisciplinary team. The management of antithrombotic therapy in patients with coronary stents undergoing surgery is thus a major challenge and should be based on a balanced decision weighing the risk of perand postoperative bleeding against the risk of stent thrombosis. If surgery on DAPT is considered too risky and the presumed risk of stent thrombosis is low, the operation is performed on low-dose aspirin after stopping the P2Y12 inhibitor prior to surgery: 3–5 days for ticagrelor and 5 days for clopidogrel and prasugrel (1–3, 12). A difficult clinical dilemma arises if surgery has to be performed without any antiplatelet therapy at all, in particular in the first month(s) after coronary stenting, and especially if the P2Y12 inhibitor has to be stopped within the first days or weeks after stenting (13). The latter situation is not uncommon and the risk of adverse cardiac events is very high and might be further enhanced by the proinflammatory and prothrombotic state associated with surgery (14, 15). Patients with recent ACS, diabetes, low ejection fraction, renal failure and patients who have been undergoing extensive stenting for three vessel disease or left main disease are at particularly high risk (16, 17). In such situations, particular attention is needed and it is recommended that these patients are admitted to a hospital with 24/7 PCI facilities (12). In cases where the risk of stent thrombosis is assumed to be very high, initiation of parenteral antithrombotic bridging therapy should be considered (12, 18).