Coronary stents: factors contributing to perioperative major adverse cardiovascular events

Patients with coronary stents undergoing non-cardiac surgery are at increased risk of major adverse cardiovascular events perioperatively. Impeccable patient care and communication between all members of the healthcare team will minimize this risk. The dominant risk factor for stent thrombosis and major adverse cardiovascular events is the interruption of dual antiplatelet therapy (e.g. aspirin and clopidogrel). If clopidogrel therapy has to be interrupted due to increased risk of bleeding, continuation of aspirin is strongly recommended to reduce the risk of stent thrombosis. The interval between percutaneous coronary interventions and operation is the next major risk factor for stent thrombosis. The incidence of major adverse cardiovascular events is inversely related to this interval, with the highest mortality rate occurring <30 days after stent implantation. Ideally, for patients with drug-eluting stents, elective surgery should be delayed for at least 1 yr and for patients with bare-metal stents, the recommended minimum period is 6 weeks. The use of a neuraxial anaesthetic technique must be carefully considered due to the risk of an epidural haematoma. Perioperative monitoring should focus on early recognition of myocardial ischaemia, infarction, or both. If stent thrombosis is present, rapid triage to an interventional catheterization laboratory is essential for restoration of coronary blood flow.     

Intraoperative thrombosis of right coronary artery drug-eluting stent after 2 years of dual antiplatelet therapy

This study presents the case of intraoperative thrombosis of a right coronary drug-eluting stent and subsequent right heart ischemia more than 2 years poststent placement and after recent withdrawal of clopidogrel therapy. Dual antiplatelet therapy had been continued uninterrupted since placement until 7 days prior to surgery when clopidogrel was stopped. This case highlights the emerging evidence that drug-eluting stents are susceptible to late occlusive thrombosis on acute withdrawal of antiplatelet therapy. Right heart ischemia resolved with rapid intraoperative management and emergent cardiac catheterization. This emphasizes the necessity of immediate availability to cardiac interventional facilities, which can influence outcomes.     

Systematic review of survival after acute mesenteric ischaemia according to disease aetiology

BACKGROUND: Differentiation of acute mesenteric ischaemia on the basis of aetiology is of great importance because of variation in disease progression, response to treatment and outcome. The aim of this study was to analyse the published data on survival following acute mesenteric ischaemia over the past four decades in relation to disease aetiology and mode of treatment. METHOD: A systematic review of the available literature from 1966 to 2002 was performed. RESULTS: Quantitative analysis of data derived from 45 observational studies containing 3692 patients with acute mesenteric ischaemia showed that the prognosis after acute mesenteric venous thrombosis is better than that following acute arterial mesenteric ischaemia; the prognosis after mesenteric arterial embolism is better than that after arterial thrombosis or non-occlusive ischaemia; the mortality rate following surgical treatment of arterial embolism and venous thrombosis (54.1 and 32.1 per cent respectively) is less than that after surgery for arterial thrombosis and non-occlusive ischaemia (77.4 and 72.7 per cent respectively); and the overall survival after acute mesenteric ischaemia has improved over the past four decades. CONCLUSION: There are large differences in prognosis after acute mesenteric ischaemia depending on aetiology. Surgical treatment of arterial embolism has improved outcome whereas the mortality rate following surgery for arterial thrombosis and non-occlusive ischaemia remains poor.     

下肢动脉支架内再狭窄的诊断和治疗

随着人口老龄化的加重,下肢动脉狭窄与闭塞性疾病的发生率越来越高,同时伴随着腔内支架的广泛应用,支架内再狭窄的发生率也逐渐升高。目前治疗支架内再狭窄的技术主要有药物治疗、普通球囊、药涂球囊、金属裸支架、药物洗脱支架、腔内减容（激光、旋切）和旁路搭桥术等。单一治疗方法效果均有限,而腔内减容与药涂球囊联合既可以机械去除增生的内膜,又可以有效抑制内膜再增生,是目前治疗支架内再狭窄较为合理的方法。     

Late coronary stent thrombosis complicating urologic surgery

The current practice of withdrawing antiplatelet therapy before major surgery has been challenged by the introduction of coronary drug-eluting stents (DESs) since evidence is accumulating that a DES requires dual antiplatelet therapy for at least a year. The authors present a case demonstrating difficulty in decision-making when it comes to appropriate perioperative antiplatelet therapy. The patient experienced a coronary stent thrombosis possibly due to discontinuation of clopidogrel prior to urologic surgery.     

Late Coronary Stent Thrombosis Complicating Urologic Surgery

The current practice of withdrawing antiplatelet therapy before major surgery has been challenged by the introduction of coronary drug-eluting stents (DESs) since evidence is accumulating that a DES requires dual antiplatelet therapy for at least a year. The authors present a case demonstrating difficulty in decision-making when it comes to appropriate perioperative antiplatelet therapy. The patient experienced a coronary stent thrombosis possibly due to discontinuation of clopidogrel prior to urologic surgery.     

冠脉支架患者非心脏手术的围手术期处理

背景 近三十年来,心脏冠脉支架患者日益增多,此类患者在接受非心脏手术时其围手术期将面临特殊挑战.目的 现将重点讨论支架血栓的病理生理以及冠脉支架患者非心脏手术围手术期的处理策略.内容 冠脉支架患者为预防支架内血栓的发生,通常接受由阿司匹林和氯吡格雷为主要药物的双联抗血小板治疗,其疗程为裸金属支架bare metal s...     

Koronare Stents, duale Antiplättchentherapie und die perioperative Problematik

Up to 90% of all percutaneous coronary interventions include coronary artery stenting. Dual antiplatelet therapy, usually involving acetylsalicyl acid combined with clopidogrel, is mandatory for patients with coronary artery stents. The duration of antiplatelet therapy for bare metal stents is 3–4 weeks, for drug eluting stents 6–12 months. Preoperative discontinuation of both drugs increases the risk of stent thrombosis, continuation the risk of relevant bleeding. According to the recommendations of anaesthesiological and cardiological societies, perioperative management has to balance the risk of bleeding vs stent thrombosis. Surgery involving a high risk of bleeding can require the discontinuance of both substances. In cases of high thrombosis risk, at least the acetylsalicyl acid should be continued until the day of surgery. For patients under antiplatelet therapy scheduled for local anaesthesia, national recommendations exist. A close collaboration between the anaesthesiologist, cardiologist and surgeon is essential for appropriate pre-, intra- and postoperative management.     

Coronary stents, dual antiplatelet therapy and peri-operative problems

Up to 90% of all percutaneous coronary interventions include coronary artery stenting. Dual antiplatelet therapy, usually involving acetylsalicyl acid combined with clopidogrel, is mandatory for patients with coronary artery stents. The duration of antiplatelet therapy for bare metal stents is 3-4 weeks, for drug eluting stents 6-12 months. Preoperative discontinuation of both drugs increases the risk of stent thrombosis, continuation the risk of relevant bleeding. According to the recommendations of anaesthesiological and cardiological societies, perioperative management has to balance the risk of bleeding vs stent thrombosis. Surgery involving a high risk of bleeding can require the discontinuance of both substances. In cases of high thrombosis risk, at least the acetylsalicyl acid should be continued until the day of surgery. For patients under antiplatelet therapy scheduled for local anaesthesia, national recommendations exist. A close collaboration between the anaesthesiologist, cardiologist and surgeon is essential for appropriate pre-, intra- and postoperative management.     

Novel use of prasugrel for intracranial stent thrombosis

Dual antiplatelet therapy is established for prevention of stent thrombosis in cardiac patients, and widely utilized in neurointerventional stent cases. Aspirin and clopidogrel are typically synergistic. We present a case of clopidogrel resistance due to genetic polymorphism resulting in acute stent thrombosis during elective stent-assisted coiling, with novel use of prasugrel as an alternative platelet inhibitor in the neurovascular setting.     

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.     

Coronary artery stents: Part I. Evolution of percutaneous coronary intervention

The subspecialty of interventional cardiology has made significant progress in the management of coronary artery disease over the past three decades with the development of percutaneous coronary transluminal angioplasty, atherectomy, and bare-metal and drug-eluting stents (DES). Bare-metal stents (BMS) maintain vessel lumen diameter by acting as a scaffold and prevent collapse incurred by angioplasty. However, these devices cause neointimal hyperplasia leading to in-stent restenosis and requiring reintervention in more than 20% of patients by 6 mo. DES (sirolimus and paclitaxel) prevent restenosis by inhibiting neointimal hyperplasia. However, DESs also delay endothelialization, causing the stents to remain thrombogenic for an extended, yet unknown, period of time. Late stent thrombosis is associated with a 45% mortality rate. Premature discontinuation of antiplatelet therapy, particularly clopidogrel, is the strongest predictor of stent thrombosis. Sixty percent of patients receive stents for off-label (unapproved) indications, which also increases the frequency of stent thrombosis. Clopidogrel and aspirin are the cornerstone of therapy in the prevention of stent thrombosis in both BMS and DES. Recommendations pertaining to the optimal duration of dual-antiplatelet therapy have been debated. Both the Food and Drug Administration and the American Heart Association/American College of Cardiologists, in association with other major societies, have made recommendations to extend the duration of dual-antiplatelet therapy in patients with DES to 1 yr. The 6-wk duration of dual-antiplatelet therapy in patients with BMS remains unchanged. All patients with coronary stents must remain on life-long aspirin monotherapy. Since the introduction of percutaneous transluminal coronary angioplasty for the treatment of coronary atherosclerosis, the practice of percutaneous coronary intervention has undergone a dramatic transformation from simple balloon dilation catheters to sophisticated mechanical endoprostheses. These advancements have impacted the practice of perioperative medicine. In this series of two articles, in Part I we will review the evolution of percutaneous coronary intervention and discuss the issues associated with percutaneous transluminal coronary angioplasty and coronary stenting; in Part II we will discuss perioperative issues and management strategies of coronary stents during noncardiac surgery.     

Antiplatelet therapy and coronary stents in perioperative medicine--the two sides of the coin

New trends in interventional cardiology, e.g. the increasing practice of coronary intervention with stent implantation and the prolonged use of dual antiplatelet therapy--usually a combination of clopidogrel and aspirin--has also increased the number of patients presenting for non-cardiac surgery. The two most commonly used stent types, bare-metal stents (BMSs) and drug-eluting stents (DESs), mandate different lengths of dual antiplatelet drug therapy to avoid stent thrombosis. Perioperative caregivers face a knife-edge dilemma between perioperative stent thrombosis, due to preoperative discontinuation of antiplatelet drugs, or surgical bleeding, by continuation of therapy. Pre- and intraoperatively, the risk factors for thrombosis have to be balanced against the risk factors for surgical bleeding. As long as prospective trials are not available, the recommendations and guidelines of task forces and experts are based on retrospective studies and case reports. The perioperative management, decision trees and the importance of close interdisciplinary collaboration between cardiologists, surgeons and anaesthetists will be described.     

Drug eluting stents and anticoagulation in the perioperative setting - an interdisciplinary challenge

Drug eluting stents are nowadays more frequently used in cardiac risk patients undergoing coronary artery interventions. These stents make prolonged anticoagulation up to one year or longer necessary to avoid acute stent thrombosis. Anti-platelet drugs like clopidogrel and aspirin should therefore be continued perioperatively if possible. Decission to stop anti-plateletts should be made for each individual patient only after interdisciplinary discussion with the cardiologist, surgeon and anaesthesiologist.     

Perioperatives Management von Patienten mit Koronarstents bei nichtherzchirurgischen Eingriffen

In patients with coronary stents scheduled for surgery the question arises whether and how antiplatelet therapy should be continued. Risks of perioperative bleeding and of acute stent thrombosis have to be considered simultaneously. The bleeding risk depends primarily on the kind of surgery and on patient comorbidity. The risk of stent thrombosis is increased in these patients due to the thrombogenic surface of the stents. The main determinants are hereby the time duration after stent implantation, the kind of the stent [uncoated (bare-metal stent, BMS) or coated (drug-eluting stent, DES)], as well as angiographic and clinical patient factors. Therefore, perioperative antiplatelet therapy has to be individually adapted for each patient. Bridging with heparin is ineffective. Bridging with intravenous antiplatelet drugs during the perioperative interruption of oral antiplatelet therapy might be a potential procedure in high-risk patients. Whether bedside monitoring of antiplatelet therapy improves the perioperative management of these patients and reduces adverse outcome is object of current studies.     

Der Patient mit Koronarstent

Nowadays stents are implanted in over 90% of percutaneous coronary interventions. Depending on the type of stent implanted, dual antiplatelet therapy combining a cyclooxygenase inhibitor such as acetylsalicylic acid and an adenosine diphosphate receptor antagonist (thienopyridine) such as clopidogrel is required for 1–12 months. Premature termination of antiplatelet therapy during non-cardiac surgery significantly increases the risk of stent thrombosis and consequently myocardial infarction, whereas continuation of dual antiplatelet therapy during surgery increases the risk of severe bleeding. Accordingly, treatment recommendations have to be based on the individual relative risk. In cases with a high risk for major bleeding during surgery, interruption of antiplatelet therapy may be required, whereas in cases of a high risk of stent thrombosis, both antiplatelet drugs should be continued throughout surgery. Patients on dual antiplatelet therapy should be counseled by a team of anesthesiologists, surgeons and cardiologists, to devise the right point in time for the operation, the best perioperative antiplatelet therapy and the appropriate perioperative monitoring.     

Mechanical rotational thrombectomy in long femoropopliteal artery and stent occlusion in COVID-19 patient: Case report

IntroductionCoronavirus disease-19 (COVID-19) has been increasingly associated with thromboembolic complications. COVID-19 infection has a thrombogenic potential for stents. Herein, we report a case of stent thrombosis in diabetic obese patient COVID-19 positive where was previously released a Multilayer Flow Modulator stent (MFM) for large popliteal aneurysm.Case reportA 78-year-old male was referred to our hospital for fever and acute pain in the left leg. At history, the same patient had endovascular procedure for a large symptomatic popliteal aneurysm, treated through release of three MFM. The pulmonary CT scan showed COVID-19 infection with confirm of rhino-laryngeal swab. Duplex ultrasound and CT-angiography showed complete thrombosis of stents. The treatment consisted of mechanical thrombectomy using an 8Fr catheter Rotarex plus release of Vibahn stent-graft.DiscussionCOVID-19 patients can present arterial occlusion. In literature are not reported cases about thrombosis peripheral stent. Minimally invasive approaches in redo-procedure reduce risk of infection. Rotarex device was used in revascularization of acute and subacute iliac and femoropopliteal arteries. The goal is to have a debulking, to avoid an incomplete deployment of stent-graft. In our precedent experience, MFM and stent-graft to treatment of popliteal aneurism were safe. It is important to monitor these patients for early identification of failure and rapprochement. In this case, the COVID-19 infection was determinant in promoting thrombosis.ConclusionsCOVID-19 increases risk of thrombosis stent. In our experience debulking through Rotarex and stenting, were decisive factors for revascularization and limb salvage.     

Perioperative complications in patients with drug-eluting stents: a three-year audit at Geelong Hospital

Drug-eluting stents are a recommended treatment for lesions in the coronary arteries. Stent insertion requires the patient remain on anti-platelet medication for a minimum of six months after insertion. A serious consequence of ceasing anti-platelet medication is late stent thrombosis leading to myocardial infarction in the territory of the drug-eluting stent. Continuing anti-platelet medication can lead to excessive bleeding at the time of surgery. Understanding the risk of complications attributable to bleeding or myocardial ischaemia will help in defining the optimal management of these patients at the time of non-cardiac surgery. This study is a retrospective database analysis and case note review of all patients with drug-eluting stents presenting for non-cardiac surgical procedures over a three-year period in one centre. Twenty-four patients with drug-eluting stents inserted presented for 43 non-cardiac surgical procedures. Severe bleeding problems were encountered in one case. Three of 15 patients (20%) who ceased clopidogrel prior to surgery without alternative anti-thrombotic prophylaxis suffered myocardial infarction due to stent thrombosis. Four patients who received alternative anti-thrombotic prophylaxis did not suffer complications. All 19 patients who ceased clopidogrel remained on aspirin prior to surgery. Patients treated with drug-eluting stents for coronary artery stenosis represent a challenging group of patients for subsequent perioperative management. The risk of myocardial infarction when clopidogrel is stopped prior to surgery is 20%, if alternative anti-thrombotic prophylaxis is not used. This risk persists beyond one year after insertion of drug-eluting stents. Some treatments appear to be effective in reducing the risk of myocardial infarction.     

Clopidogrel dilemma for orthopaedic surgeons

Background: Patients medicated with clopidogrel who require orthopaedic surgery present a particular challenge. Whether in an emergency or elective situation the orthopaedic surgeon must balance the risks of ceasing clopidogrel versus the risk of increased bleeding that dual antiplatelet therapy generates. Method: This paper reviews the current published evidence regarding the risks of continuing clopidogrel, the risks of discontinuing clopidogrel and associated considerations such as venous thromboprophylaxis. Results: Little good quality evidence exists in regard to perioperative clopidogrel for orthopaedic surgery. Available evidence across non‐cardiac and cardiac surgery were assessed and presented in regards to current practices, blood loss for orthopaedic operations, risks when continuing clopidogrel, risks of stopping clopidogrel and also the consideration of venous thromboembolism. Conclusions: The patients at greatest risk, when discontinuing clopidogrel therapy, are those with drug eluting stents who may be at risk of stent thrombosis. Where possible, efforts should be made to continue clopidogrel therapy through the perioperative period, taking precautions to minimize bleeding. If the risk of bleeding is too high, antiplatelet therapy must be reinstated as soon as considered reasonable after surgery. In addition, patients on clopidogrel who sustain a fall or other general trauma need to be carefully assessed because of the possibility of occult bleeding, such as into the retroperitoneal space. Until more definitive evidence becomes available, this review aims to provide a guide for the orthopaedic surgeon in dealing with the difficult dilemma of the patient on clopidogrel therapy, recommending that orthopaedic surgeons take a team approach to assess the individual risks for all patients and consider continuation of clopidogrel therapy perioperatively where possible.     

Blood flow and thrombus formation determine the development of stent neointima

To establish a relationship between flow, acute thrombus formation, and late intimal formation in implanted arterial stents, canine femoral arteries with normal blood flow were compared to contralateral femoral arteries with restricted blood flow. Thrombocyte activity over the stent segment was evaluated for 3 h after stent placement with nuclear scanning, following administration of In-111 labeled platelets. To evaluate long-term stent patency in relationship to arterial flow, an additional group of dogs were subjected to long-term observation. Matched, symmetrically implanted femoral stents with normal and restricted flow were explanted at 1, 12, and 24 weeks for histological analysis and comparative measurement of neointimal thickness. Angiographic studies were performed before and after nuclear scan in the acute animals and before explant in the chronic animals. Acutely, heparinization prevented subocclusive or occlusive thrombus, regardless of flow. In the absence of heparinization, normal arterial blood flow did not prevent thrombus formation on stents. Chronically, stents with flow restriction had significantly greater neointimal formation in comparison with unrestricted stents. Histological studies suggested that the stent neointima resulted from progressive replacement of stent thrombus.