Low-dose aspirin for secondary cardiovascular prevention - cardiovascular risks after its perioperative withdrawal versus bleeding risks with its continuation - review and meta-analysis

OBJECTIVES: Low-dose aspirin given for secondary prevention of cardiovascular disease is frequently withdrawn prior to surgical or diagnostic procedures to reduce bleeding complications. This may expose patients to increased cardiovascular morbidity and mortality. Aim of the study was to review and quantify cardiovascular risks because of periprocedural aspirin withdrawal and bleeding risks with the continuation of aspirin. METHODS: We screened MEDLINE (January 1970-October 2004) with additional manual cross-referencing for clinical studies, surveys on the opinions of doctors and guidelines. RESULTS: Studies reporting the relative risk of acute cardiovascular events after aspirin withdrawal when compared with its continuation were not found. However, retrospective investigations revealed that aspirin withdrawal precedes up to 10.2% of acute cardiovascular syndromes. The time interval between discontinuation and acute cerebral events was 14.3 +/- 11.3 days, 8.5 +/- 3.6 days for acute coronary syndromes, and 25.8 +/- 18.1 days for acute peripheral arterial syndromes (P < 0.02 versus acute coronary syndromes). On aspirin-related bleeding risks, we obtained 41 (12 observational retrospective, 19 observational prospective, 10 randomized) studies, reporting on 49 590 patients (14 981 on aspirin). Baseline frequency of bleeding complications varied between 0 (skin lesion excision, cataract surgery) and 75% (transrectal prostate biopsy). Whilst aspirin increased the rate of bleeding complications by factor 1.5 (median, interquartile range: 1.0-2.5), it did not lead to a higher level of the severity of bleeding complications (exception: intracranial surgery, and possibly transurethral prostatectomy). Surveys amongst doctors on the management of this problem demonstrate wide variations. Available guidelines are scarce and in part contradictory. CONCLUSIONS: Only if low-dose aspirin may cause bleeding risks with increased mortality or sequels comparable with the observed cardiovascular risks after aspirin withdrawal, it should be discontinued prior to an intended operation or procedure. Controlled clinical studies are urgently needed.     

Risk and management of upper gastrointestinal bleeding associated with prolonged dual-antiplatelet therapy after percutaneous coronary intervention

Prolonged dual-antiplatelet therapy with aspirin and clopidogrel is mandatory after drug-eluting stent implantation because of the potential increased risk of late stent thrombosis. The concern regarding prolonged antiplatelet therapy is the increased risk of bleeding. Gastrointestinal bleeding is the most common site of bleeding and presents a serious threat to patients due to the competing risks of gastrointestinal hemorrhage and stent thrombosis. Currently, there are no guidelines and little evidence on how best to manage these patients who are at high risk of morbidity and mortality from both the bleeding itself and the consequences of achieving optimum hemostasis by interruption of antiplatelet therapy. Managing gastrointestinal bleeding in a patient who has undergone recent percutaneous coronary intervention requires balancing the risk of stent thrombosis against further catastrophic bleeding. Close combined management between gastroenterologist and cardiologist is advocated to optimize patient outcomes.     

Diagnostische Laparoskopie unter doppelter thrombozytenaggregationshemmender Therapie mit Clopidogrel und ASS

Dual antiplatelet therapy using aspirin and a thienopyridine (e.g. clopidogrel) is known to be essential in patients in whom percutaneous coronary intervention with stent implantation has been performed in order to prevent stent thrombosis and its fatal consequences. On the other hand dual antiplatelet therapy increases the incidence of perioperative bleeding complications. In case of urgent or emergency surgery the risk of perioperative stent thrombosis on the one hand and the perioperative bleeding risk on the other has to be evaluated carefully in order to keep time period without sufficient platelet inhibition as short as possible. The presented case offers a strategy for managing perioperative administration of antiplatelet agents.     

Double jeopardy: balance between bleeding and stent thrombosis with prolonged dual antiplatelet therapy after drug-eluting stent implantation

Prolonged dual antiplatelet therapy with aspirin and clopidogrel is mandatory after drug-eluting stent (DES) implantation because of potential increase risk of stent thrombosis compared to bare-metal stents. As more DES are being implanted, many of these patients will undergo non-cardiac surgery whilst on antiplatelet therapy. The optimal management of perioperative antiplatelet therapy is not well established. The risk of excessive bleeding associated with antiplatelet therapy needs to be balanced against the risk of stent thrombosis with interruption of antiplatelet therapy on a case-to-case basis.     

Clinical outcomes associated with per‐operative discontinuation of aspirin in patients with coronary artery disease: A systematic review and meta‐analysis

Background: Postoperative state is characterized by increased thrombotic risk by virtue of platelet activation. Whether aspirin ameliorates this risk in patients with established coronary artery disease undergoing cardiac or noncardiac surgery is unknown. We conducted a systematic review and meta‐analysis to compare the risk of major adverse cardiac events (MACE) and the risk of bleeding in patients with early (3–5 or more days before surgery) vs. late discontinuation(<3–5 days)/no discontinuation of aspirin. Methods: Multiple databases were searched from inception of these databases until March 2015 to identify studies that reported discontinuation of aspirin in patients undergoing surgery. The outcomes measured were all cause mortality, nonfatal myocardial infarction and other relevant thrombotic events (MACE) which also may include, fatal and nonfatal MI, stent thrombosis and restenosis, stroke, perioperative cardiovascular complications (heart failure, MI, VTE, acute stroke) and perioperative bleeding during the perioperative period to up to 30 days after surgery. Results: A total of 1,018 titles were screened, after which six observational studies met the inclusion criteria. Our analysis suggests that there is no difference in MACE with planned discontinuation of aspirin (OR = 1.17, 95% CI = 0.76–1.81; P = 0.05; I² = 55%). Early discontinuation of aspirin showed a decreased risk of peri‐operative bleeding (OR 0.82, 95% CI = 0.67–0.99; P = 0.04; I² = 42%). Conclusion: Our analysis suggests that planned short‐term discontinuation in the appropriate clinical setting appears to be safe in the correct clinical setting with no increased risk of thrombotic events and with a decreased risk of bleeding. © 2016 Wiley Periodicals, Inc.     

Therapie mit Thrombozytenfunktionshemmern bei operativen Eingriffen

The platelet function inhibitors (PFI) acetylsalicylic acid (ASA) and clopidogrel are widely used in a broad spectrum of atherothrombotic diseases, either as mono- or dual antiplatelet therapy. Platelet function is inhibited for the whole lifespan of platelets (10 days). In case of surgical procedures the bleeding risk under continued antiplatelet therapy has to be balanced against the risk of ischemic complications due to withdrawal of antiplatelet therapy. Especially after stent implantation, the high risk and unfavorable prognosis of stent thrombosis have to be considered. Whereas surgical procedures with a low bleeding risk may be performed with continued antiplatelet therapy, there is a need for partial or total discontinuation of antiplatelet therapy in surgical procedures with higher bleeding risks.     

Perioperative management of a patient with recently placed drug-eluting stents requiring urgent spinal surgery

Patients receiving drug-eluting coronary stents (DES) require antiplatelet therapy for at least 12 months to prevent stent thrombosis (ST), a potentially calamitous event. Since interruption of antiplatelet therapy is the greatest risk factor for ST, it is imperative that the decision to discontinue these agents be based on an accurate assessment of the patient’s risk for bleeding complications. Individuals who are regarded as being at a high risk are those undergoing intracranial, spinal or intraocular surgeries. These patients require alternative agents during the perioperative period to minimize both their risk of perioperative thrombosis and intraoperative hemorrhage. We report the case of a woman who required spinal surgery 3 months after she underwent placement of two drug-eluting stents. The patient’s clopidogrel was stopped 5 days prior to surgery and an infusion of eptifibatide was used to “bridge” antiplatelet therapy during the perioperative period. Postoperatively, anticoagulation therapy was reinstituted using aspirin with clopidogrel. This case serves as a successful example of bridging therapy using a short acting and gycoprotein (GP) IIb/IIIa inhibitor as a means of maintaining antiplatelet therapy during the perioperative period to minimize the risk of stent thrombosis and the risk of intraoperative bleeding.KEY WORDS: antiplatelet management, stents, surgery     

Betreuung von Patienten nach Koronarstentimplantation

The introduction of Drug Eluting Stents was an important step to reduce restenosis rate after coronary stent implantation. Unfortunately, reduction of restenosis was paid off by the price of potential increased late (>30 days) stent thrombosis. However, current data are not completely conclusive with respect to extent and duration of stent thrombosis and cardiovascular risk after drug eluting stent implantation. Until now, especially for patients at risk for stent thrombosis a prolonged (12 instead of 6 months) dual antiplatelet therapy with aspirin and clopidogrel is recommended. Thereby, the quality of physician instructions is predictive for patient’s compliance. Premature termination of dual antiplatelet therapy should be avoided; many small surgical interventions (e.g. tooth extraction) can be performed under dual antiplatelet therapy. Patients with “triple therapy” (aspirin, clopidogrel and coumarin derivate) should be monitored carefully, since they have an excessive bleeding risk. An elective coronary angiography after coronary stent implantation is not routinely necessary. However in selected high-risk patients (e.g. left main or multivessel stent implantation) control angiography may be useful. Medical therapy of risk factors (hyperlipidemia, hypertension, and diabetes mellitus) is essential also after coronary stent implantation. It is important to screen patients for diabetes mellitus, since approximately 1/3 of patients after coronary intervention have an otherwise unrecognized diabetes mellitus or glucose tolerance disturbance.     

Cilostazol added to aspirin and clopidogrel reduces revascularization without increases in major adverse events in patients with drug-eluting stents: A meta-analysis of randomized controlled trials

Background

The effects of cilostazol added to aspirin and clopidogrel (triple antiplatelet therapy: TAT) on clinical outcomes after drug-eluting stent (DES) implantation are unknown.

Methods

We conducted a meta-analysis of randomized controlled trials (RCTs) comparing TAT with aspirin and clopidogrel (dual antiplatelet therapy: DAT) in DES patients. Clinical end points were target lesion (TLR) and/or vessel (TVR) revascularization, death, myocardial infarction (MI), stent thrombosis (ST), bleeding, rash, gastrointestinal (GI) side effects, and drug discontinuation. We calculated the pooled estimate based on a fixed-effects model using Peto odds ratio (OR) for rare events. If heterogeneity was observed across an individual RCT, an analysis based on a random-effects model was performed.

Results

Eight RCTs were included in this meta-analysis, involving 3590 patients (TAT:DAT = 1800:1790). Up to 24 months, TAT showed a significant reduction in TLR (OR: 0.58, 95% confidence interval (CI): 0.43 to 0.78, p < 0.001) and TVR (OR: 0.58, 95% CI: 0.40 to 0.83, p = 0.003) compared with DAT. The incidence of death, MI, ST, or overall or major bleeding was comparable between the 2 groups, whereas the proportion of rash (OR: 2.50, 95% CI: 1.52 to 4.10, p < 0.001), GI side effects (OR: 3.14, 95% CI: 1.79 to 5.50, p < 0.001), or drug discontinuation (OR: 6.81, 95% CI: 2.12 to 21.86, p < 0.001) was higher in TAT than DAT.

Conclusions

In this meta-analysis, TAT was associated with significantly effective outcomes for TLR and TVR without any increase in major adverse events but was associated with tolerance issues compared with DAT after DES implantation.     

Focused clinical review: periprocedural management of antiplatelet therapy in patients with coronary stents

Coronary stent implantation, particularly drug eluting stents, is now the major method of coronary revascularisation. Following drug-eluting stent implantation dual antiplatelet therapy with aspirin and thienopyridine is recommended for at least 12 months. Premature discontinuation, often at the time of noncardiac surgery, has been associated with stent thrombosis which has a significant risk of death and myocardial infarction. Late (>30 days) and very late (>365 days) stent thrombosis appears to more common with DES and poses the questions of when is it safe to stop antiplatelet therapy post coronary stenting and how to manage patients who need non-cardiac surgery. This article reviews the evidence for stent thrombosis and the peri-operative management of patients with coronary stents and provides an algorithm for patient management based on multidisciplinary assessment of bleeding risk, perioperative cardiac event and stent thrombosis risk.     

Antiplatelet drugs: mechanisms and risks of bleeding following cardiac operations

Preoperative antiplatelet drug use is common in patients undergoing coronary artery bypass grafting (CABG). The impact of these drugs on bleeding and blood transfusion varies. We hypothesize that review of available evidence regarding drug-related bleeding risk, underlying mechanisms of platelet dysfunction, and variations in patient response to antiplatelet drugs will aid surgeons as they assess preoperative risk and attempt to limit perioperative bleeding. The purpose of this review is to (1) examine the role that antiplatelet drugs play in excessive postoperative blood transfusion, (2) identify possible mechanisms to explain patient response to antiplatelet drugs, and (3) formulate a strategy to limit excessive blood product usage in these patients. We reviewed available published evidence regarding bleeding risk in patients taking preoperative antiplatelet drugs. In addition, we summarized our previous research into mechanisms of antiplatelet drug-related platelet dysfunction. Aspirin users have a slight but significant increase in blood product usage after CABG (0.5 U of nonautologous blood per treated patient). Platelet adenosine diphosphate (ADP) receptor inhibitors are more potent antiplatelet drugs than aspirin but have a half-life similar to aspirin, around 5 to 10 days. The American Heart Association/American College of Cardiology and the Society of Thoracic Surgeons guidelines recommend discontinuation, if possible, of ADP inhibitors 5 to 7 days before operation because of excessive bleeding risk, whereas aspirin should be continued during the entire perioperative period in most patients. Individual variability in response to aspirin and other antiplatelet drugs is common with both hyper- and hyporesponsiveness seen in 5 to 25% of patients. Use of preoperative antiplatelet drugs is a risk factor for increased perioperative bleeding and blood transfusion. Point-of-care tests can identify patients at high risk for perioperative bleeding and blood transfusion, although these tests have limitations. Available evidence suggests that multiple blood conservation techniques benefit high-risk patients taking antiplatelet drugs before operation. Guidelines for patients who take aspirin and/or thienopyridines before cardiac procedures include some or all of the following: (1) preoperative identification of high-risk patients using point-of-care testing; (2) withdrawal of aspirin or other antiplatelet drugs for a few days and delay of operation in patients at high risk for bleeding if clinical circumstances permit; (3) selective perioperative use of evidence-based blood conservation interventions (e.g., short-course erythropoietin, off-pump procedures, and use of intraoperative blood conservation techniques), especially in high-risk patients; and (4) platelet transfusions if clinical bleeding occurs.     

Care of patients after coronary stent implantation: what is important in practice?

The introduction of Drug Eluting Stents was an important step to reduce restenosis rate after coronary stent implantation. Unfortunately, reduction of restenosis was paid off by the price of potential increased late (>30 days) stent thrombosis. However, current data are not completely conclusive with respect to extent and duration of stent thrombosis and cardiovascular risk after drug eluting stent implantation. Until now, especially for patients at risk for stent thrombosis a prolonged (12 instead of 6 months) dual antiplatelet therapy with aspirin and clopidogrel is recommended. Thereby, the quality of physician instructions is predictive for patient's compliance. Premature termination of dual antiplatelet therapy should be avoided; many small surgical interventions (e.g. tooth extraction) can be performed under dual antiplatelet therapy. Patients with "triple therapy" (aspirin, clopidogrel and coumarin derivate) should be monitored carefully, since they have an excessive bleeding risk. An elective coronary angiography after coronary stent implantation is not routinely necessary. However in selected high-risk patients (e.g. left main or multivessel stent implantation) control angiography may be useful. Medical therapy of risk factors (hyperlipidemia, hypertension, and diabetes mellitus) is essential also after coronary stent implantation. It is important to screen patients for diabetes mellitus, since approximately 1/3 of patients after coronary intervention have an otherwise unrecognized diabetes mellitus or glucose tolerance disturbance.     

Need antiplatelet therapy be interrupted in drug eluting stent recipients throughout the periendoscopic period? A very late stent thrombosis case report and review of the literature

In-stent thrombosis after cessation of antiplatelet medications in patients with drug-eluting stents （DES） is a significant problem in medical practice, particularly in the perioperative period. We report a case of an 87-year-old man with a medical history of hypertension, coronary artery disease and chronic atrophic gastritis. Very late thrombosis of a sirolimus-eluting stent occurred 1207 days after implantation, seven months after discontinuation of clopidogrel, and the interruption of aspirin 13 days in preparation of an elective endoscopic gastroin-testinal procedure presented with acute myocardial infarction. The patient was treated with thrombectomy and successfully revascularized with superimposition of two sirolimus-eluting stents. Medications administered in the catheterization laboratory included low molecular weight heparin and nitroglycerin. Flow was defined as grade 2 according to the thrombolysis in myocardial infarction scale. Electrocardio-gram after the procedure revealed persistent, but decreased, ST-segment elevation in the anterolateral leads. The patient recovered and was discharged on aspirin and clopidogrel indefinitely. There was no cardiac event during the two year follow-up period. This case underlines the importance of maintaining the balance of thrombosis and bleeding during perioperation of non-cardiac procedure and the possible need for continuation of aspirin therapy during periendoscopic procedures among patients with low bleeding risks who received DES.     

Combined antiplatelet therapy with ticlopidine and aspirin: A simplified approach to intracoronary stent management

Intravascular metallic stents are increasingly used in the non-surgicalmanagement of coronary atherosclerosis. Despite intensive anticoagulation,subacute stent thrombosis, which usually has serious clinicalconsequences, and major haemorrhagic complications remain majorproblems after stent implantation. In addition, conventionalmanagement with anticoagulant therapy requires prolonged hospitalization. In a prospective multicentre study, we investigated the efficacyof a combination of two antiplatelet agents, ticlopidine 500mg daily and aspirin 200 mg daily, without oral anticoagulationafter stent implantation. Since November 1993, 529 consecutivepatients, in whom 545 vessels were successfully stented withconventional (non-hepann coated) stents have been enrolled.Stenting was performed as a bailout procedure for failed angioplastyin 112 patients, for a suboptimal result after angioplasty in314 patients, and electively in the remaining 103 patients. Coronary events related, or possibly related, to stent thrombosisoccurred in 54% of patients stented as a bailout procedure andin 1.8% of patients stented for a suboptimal result. Seriousbleeding complications occurred in 5.4% of patients stentedas a bailout procedure and 1.5% of patients stented for a suboptimalresult. Neither stent thrombosis nor serious bleeding complicationswere seen in patients stented electively. Ticlopidine therapywas discontinued in 1.9% of patients due to neutropenia (0.6%)or rash (1.3%). Mean hospital stay decreased from 6.16 ±2.14 days to 4.2±2.15 days during the study period. A combination of two antiplatelet agents can be employed inthe vast majority of patients after coronary stent implantation.Subacute stent thrombosis rates and bleeding com plicationscompare favourably with those reported using conventional therapyand the duration of hospitalization is reduced.     

Cilostazol combined with P2Y12 receptor inhibitors: A substitute antiplatelet regimen for aspirin‐intolerant patients undergoing percutaneous coronary stent implantation

BackgroundCilostazol combined with P2Y₁₂ receptor inhibitor has been used as a substitute regimen for aspirin‐intolerant patients undergoing percutaneous coronary stent implantation on a small scale. Its exact impact on platelet functions and clinical benefits of aspirin‐intolerant patients is unknown.HypothesisCilostazol combined with P2Y₁₂ receptor inhibitors could be used as a substitute antiplatelet regimen for aspirin‐intolerant patients undergoing percutaneous coronary stent implantation.MethodsIn this multicenter prospective cohort trial, patients undergoing elective percutaneous coronary stent implantation were assigned to the cilostazol group (cilostazol plus P2Y₁₂ receptor inhibitors), based on aspirin intolerance criteria, or the aspirin group (aspirin plus P2Y₁₂ receptor inhibitors). Platelet PAC‐1, CD62p, and vasodilator‐stimulated phosphoprotein phosphorylation (VASP‐P) were detected by flow cytometry. The primary endpoints were major adverse cardiovascular and cerebrovascular events (MACCE) including all‐cause death, acute myocardial infarction, emerging arrhythmia, nonfatal stroke, and heart failure. The secondary endpoints were the Bleeding Academic Research Consortium (BARC) bleeding events.ResultsOne hundred and fifty‐four aspirin‐intolerant percutaneous coronary stent implantation patients and 154 matched aspirin‐tolerant patients from a total of 2059 percutaneous coronary stent implantation patients were enrolled. The relative activation level of PAC‐1, CD62p, and platelet reaction index reflected by the VASP‐P test were similar in the two groups (p > .05). After 12 months of follow‐up, the incidence of all‐cause death was 1.9% in the cilostazol group and 1.3% in the aspirin group (risk ratio [RR], 1.500; 95% confidence interval [CI], 0.254–8.852; p = 1.000); the incidence of acute myocardial infarction was 0.6% in the cilostazol group and 1.3% in the aspirin group (RR, 0.500; 95% CI, 0.046–5.457; p = 1.000). No significant difference was seen in other MACCE events, or in any types of BARC bleeding events.ConclusionsCilostazol combined with P2Y₁₂ inhibitors was not inferior to aspirin‐based standard therapy and could be used as a reasonable substitute antiplatelet regimen for aspirin‐intolerant patients undergoing percutaneous coronary stent implantation, but again with limitations, which required a larger sample and longer follow‐up to confirm its efficacy.     

Combination therapy with aspirin, clopidogrel and warfarin following coronary stenting is associated with a significant risk of bleeding

Dual antiplatelet therapy of aspirin and a thienopyridine is the standard of care following coronary stenting. Patients who are on chronic warfarin therapy and receive a coronary stent need to be treated with the triple therapy of aspirin, clopidogrel and warfarin; however, the bleeding risk in these patients is unknown. To evaluate the bleeding risk in patients requiring chronic warfarin therapy and undergoing stent implantation, we compared 107 consecutive patients on chronic warfarin therapy who underwent coronary stenting and were discharged on aspirin, clopidogrel and warfarin to 107 contemporary patients who were treated with aspirin and clopidogrel. We evaluated their bleeding history before and after coronary stenting. Major bleeding was defined as bleeding that was significantly disabling, intraocular or requiring at least 2 units of blood transfusion. Minor bleeding was defined as other bleeding that led to interruption of the medications. Patients on triple therapy were younger and more likely to have hypertension. This group had significantly higher major bleeding (6.6% vs. 0%; p = 0.03) and minor bleeding (14.9% vs. 3.8%; p = 0.01) compared with the dual antiplatelet therapy group. In the triple therapy group, the international normalized ratio or aspirin dosage did not influence the bleeding risk. In patients requiring warfarin therapy, the addition of dual antiplatelet therapy is associated with an approximately 7% major bleeding risk. Thus, novel regimens are needed to reduce the bleeding risk.     

Incidence,predictors and prognostic value of serious hemorrhagic complications following transcatheter aortic valve implantation

Background

TAVI is an alternative solution for patients with aortic valve stenosis (AS) who are refused for conventional surgery. We sought to evaluate the incidence, characteristics, predictors and prognosis impact of serious hemorrhagic complications following transcatheter aortic valve implantation (TAVI).

Methods

One hundred and seventy one consecutive patients with symptomatic severe AS (83.5 ± 6.1 y; 53% women; mean EuroSCORE = 22.1 ± 12.3) underwent transapical (TA) or transfemoral (TF) TAVI in our institution using Edwards SAPIEN© and Medtronic CoreValve© devices. The primary evaluated criterion was the incidence of any bleeding complication, according to the Valve Academic Research Consortium (VARC) criteria.

Results

VARC serious hemorrhagic complications occurred in 34.5% of patients (n = 23 life-threatening/disabling (LT/D) and n = 36 major bleedings). Most of these complications were related to access site complications (69%). Multivariable analysis revealed that TA access, low weight and underlying coronary artery diseases were independent predictors for development of serious bleeding. The mortality was significantly higher in patients with serious events compared to patients without bleeding (p = 0.008, log-rank analysis). Although the survival didn't significantly differ in patients with major hemorrhagic events, subjects with LT/D bleeding events had a higher mortality than the subjects with no hemorrhagic complications (p < 0.001, log-rank analysis). Occurrence of VARC LT/D event independently predicted all-cause mortality (HR = 5.35 [2.51–11.43], p < 0.001) during the first year following TAVI in multivariate Cox regression analysis.

Conclusion

Severe bleeding is frequent following TAVI procedure and is mainly related to local hemorrhage. VARC LT/D events are associated with decreased survival after AS correction.     

Management der interventionellen Therapie von Patienten mit akutem Koronarsyndrom und Vorhofflimmern

Atrial fibrillation (AF) is a common arrhythmia following acute myocardial infarction and the overall percentage observed in previous studies ranges between 10 and 12%. Acute coronary syndrome (ACS) and AF are associated with a higher in-hospital and long-term mortality. Predisposing factors are higher bleeding complications, higher incidence of stroke, heart failure and cardiogenic shock. Access site complications can be significantly reduced using the transradial approach for PCI which improves the clinical outcome of these patients. Stroke is an important complication in patients hospitalized with ACS. The incidence of acute stroke in patients with ACS and AF varies between 0.5 and 1.3%. The increasing use of drug-eluting stents (DES) to minimize in-stent restenosis necessitates long-term dual antiplatelet therapy with aspirin plus a thienopyridine (at present most frequently clopidogrel) to reduce the risk of early and late stent thrombosis. Combined aspirin-clopidogrel therapy, however, is less effective in preventing stroke compared with oral anticoagulation (OAC) alone—and OAC alone is insufficient to prevent stent thrombosis. In patients with ACS and AF a triple therapy consisting of aspirin, clopidogrel and OAC (INR 2.0–2.5) is recommended according to the risk stratification (CHA₂DS₂-VASc score), the bleeding risk (HAS-BLED score), and the implanted stent (DES vs BMS). Triple therapy is associated with a higher bleeding risk and should be administered as briefly as necessary. Using beta-blockers, ACE inhibitors, direct current cardioversion or intravenous administration of amiodarone may reduce the incidence of AF and restore sinus rhythm which can reduce the duration of triple therapy.     

冠心病支架术后行非心脏手术围手术期的抗栓治疗

目的探讨冠心病药物涂层支架置入患者行非心脏手术围手术期的抗栓治疗策略。方法选择2010年1月至2013年6月,因冠心病置入药物涂层支架服用双联抗血小板药物期间因外科疾病需手术治疗的16例患者,术前3～5 d停用双联抗血小板药物,应用替罗非班0.1μg/(kg.min)持续泵入,术前8 h停用替罗非班,外科手术后若无明显出血情况,在术后24～48 h恢复氯吡格雷、阿司匹林双联抗血小板治疗。观察围手术期及3个月随访期主要心血管事件以及出血事件的发生情况。结果 16例患者围手术期未发生心血管事件,未发生大出血事件,发生轻微出血2例。结论药物涂层支架置入术后近期行非心脏手术患者围手术期应用血小板表面糖蛋白Ⅱb/Ⅲa受体拮抗剂替代双联抗血小板药物是有效和安全的。但本研究的例数偏少,有必要进行大规模随机对照研究进一步证实     

Coronary syndromes following aspirin withdrawal: a special risk for late stent thrombosis

OBJECTIVES: We sought to determine whether aspirin withdrawal is an encountered situation in coronary disease patients who relapsed. BACKGROUND: Despite the recognized benefits of aspirin in coronary disease, and because of the threat of bleeding or poor compliance, aspirin intake is sometimes stopped. It is not known whether withdrawal of aspirin can be harmful in coronary-disease patients. METHODS: Between September 1999 and April 2002, a total of 1,236 patients hospitalized for acute coronary syndrome (ACS) were questioned in order to determine whether aspirin intake had been interrupted. RESULTS: Fifty-one of these ACSs occurred within 1 month after aspirin withdrawal. This represents 4.1% of all coronary events but 13.3% of recurrences. Among those patients who relapsed, the incidence of ST-segment elevation ACS was higher in those who stopped aspirin when compared to the 332 patients who did not stop aspirin (39% vs. 18%; p = 0.001). Ten (20%) cases involved a thrombosis of an uncoated stent implanted on average 15.5 +/- 6.5 months previously. Mean delay between aspirin withdrawal and the acute coronary event was 10 +/- 1.9 days. Reasons for aspirin withdrawal included minor surgery in 7 cases, fibroscopy in 8 cases, dental treatment in 13 cases, bleeding in 3 cases, and patient non-compliance in 20 cases. CONCLUSIONS: Our results support the hypothesis that aspirin withdrawal in coronary patients may represent a real risk for the occurrence of a new coronary event. Many cases involved late uncoated-stent thrombosis. Assessment of the exact incidence of coronary recurrences after aspirin withdrawal will need prospective studies.