|Year : 2019 | Volume
| Issue : 1 | Page : 11-20
Risk of gastrointestinal bleed and endoscopic procedures on antiplatelet and antithrombotic agents
Partha Pal, Manu Tandan, Duvvuru Nageshwar Reddy
Department of Medical Gastroenterology, Asian Institute of Gastroenterology, Hyderabad, Telangana, India
|Date of Web Publication||19-Jun-2019|
Department of Medical Gastroenterology, Asian Institute of Gastroenterology, 6-3-661, Somajiguda, Hyderabad, Telangana
Source of Support: None, Conflict of Interest: None
The use of antiplatelet and antithrombotic agents has increased hand in hand with the number and complexity of endoscopic procedures. Hence, the endoscopists are often faced with considering endoscopy in patients on these agents. In this setting, to make informed decision, four key aspects are need to be considered. The type of antithrombotic or antiplatelet agent used and its characteristics, risk of thromboembolic events (which can lead to ischemic stroke or acute coronary syndrome, both of which carry high morbidity) due to withholding the drug, risk of bleeding (increases with invasiveness of procedure), and timing of procedure (elective or urgent) are the key factors to consider. We aim to discuss the risk of gastrointestinal bleed and endoscopic procedures on antiplatelet and antithrombotic agents focusing on Indian context based on recent Asia-pacific guidelines along with other existing guidelines.
Keywords: Antiplatelets, antithrombotic agents, endoscopy, gastrointestinal bleeding
|How to cite this article:|
Pal P, Tandan M, Reddy DN. Risk of gastrointestinal bleed and endoscopic procedures on antiplatelet and antithrombotic agents. J Dig Endosc 2019;10:11-20
|How to cite this URL:|
Pal P, Tandan M, Reddy DN. Risk of gastrointestinal bleed and endoscopic procedures on antiplatelet and antithrombotic agents. J Dig Endosc [serial online] 2019 [cited 2019 Aug 21];10:11-20. Available from: http://www.jdeonline.in/text.asp?2019/10/1/11/259954
| Introduction|| |
Gastrointestinal (GI) bleed is one of the most common medical emergencies in day-to-day practice. With increase in age and comorbidities, the use of antithrombotic agents (antiplatelet and anticoagulant agents) is widely prevalent, and this has added an additional dimension in the management of patients with GI bleed or those requiring a therapeutic endoscopic procedure. A balance between the risk of procedural hemorrhage and the risk of thromboembolism on discontinuation of antithrombotic agents is essential. Knowledge of drug pharmacokinetics and urgency of the procedure are the other facts to consider [Table 1]. A close cooperation is essential between physician, cardiologist, and the endoscopist for the proper management of such patients who require GI endoscopy.
|Table 1: Key factors to consider for periprocedural management of patients on antiplatelets and anticoagulants undergoing endoscopy|
Click here to view
| Types of Antiplatelet or Antithrombotic Drug|| |
The endoscopist should inquire about the drugs (antiplatelet and antithrombotic agents) that the patient is taking. The knowledge of mechanism of action, onset and offset of action, pharmacokinetics, drug interactions, and risk of bleeding with each agent is essential for periendoscopic management of patients on antiplatelet or antithrombotic agents. The timing of discontinuation before endoscopy and resumption after endoscopic hemostasis is discussed in detail later in the manuscript. Summary of properties of oral antiplatelets and anticoagulant agents is given in [Table 2].,
|Table 2: Summary of properties of commonly used oral antiplatelets and anticoagulant agents|
Click here to view
| Host's Risk Of Thrombosis|| |
Risk of thrombosis on stopping antithrombotic agents depends on underlying cardiovascular/cerebrovascular/peripheral vascular status or presence of prothrombotic states. This determines the risk of thrombosis and timing of resumption of antiplatelets or antithrombotic agents.
Risk of thrombosis post coronary stent/coronary artery disease/cerebrovascular or peripheral arterial disease
The risk of stent thrombosis due to discontinuation of antithrombotic agents can be very high, high, and moderate/low based on timing of discontinuation after acute coronary syndrome/percutaneous coronary intervention (ACS/PCI): <6 weeks, 6 weeks–6 months, and >6 months, respectively, according to APAGE/APSDE guidelines. Stable coronary artery disease, cerebrovascular disease, and peripheral arterial disease also fall under low-risk category. For very high-risk category, the procedure should be deferred, and for high-risk cases, defer procedure if possible to >6 months. For low-risk cases, the procedure should not be deferred. The difference between high and low risk is that for discontinuing antithrombotic agents, high-risk patients need heparin-bridging therapy. These have been detailed in [Table 3].
|Table 3: Thrombotic risk category and antithrombotic therapy management in elective endoscopic procedures|
Click here to view
This recommendation is based on a recent retrospective cohort study based on data of 42,000 patients undergoing surgery within 24 months of placement of coronary stent. The incidence of major adverse cardiac events (MACEs) after surgery within 6 weeks, 6 weeks to 6 months, 6–12 months, and >12–24 months was 11.6%, 6.4%, 4.2%, and 3.5%, respectively. MACE incidence was not different between drug-eluting stent (DES) and bare metal stent (BMS), and risk of MACEs was stable after 6 months in both DES and BMS.
On the other hand, the British Society of Gastroenterology/European Society of GI Endoscopy (BSG-ESGE) and the American Society of Gastroenterology (ASGE) guidelines are based on the 2014 American College of Cardiology/American Heart Association guidelines that stated that the risk of noncardiac surgery is high in patients with BMS placed within 1 month or DES placed within 12 months. The American College of Chest Physicians recommends delaying noncardiac surgery for 6 weeks for BMS and 6 months in case of DES.
Risk of thrombosis in prothrombotic states
Different societies have stratified patients according to their risk of thromboembolism during discontinuation of warfarin. The criteria for bridging therapy differ in different guidelines. In ESGE guidelines, nonvalvular atrial fibrillation (AF) was considered low risk irrespective of their CHA2DS2VASc score (congestive heart failure – 1 point, hypertension – 1 point, age ≥75 years – 2 points, diabetes mellitus –1 point, stroke – 2 points, vascular disease – 1 point, age 65–74 years – 1 point, female sex – 1 point, and total points – 9) as there is a significantly higher risk of bleeding with bridging therapy compared to no bridging therapy in RE-LY trial. However, the data could not be extrapolated to patients with mitral stenosis or CHA2DS2VASc score >5 due to small number of such patients. The role of bridge therapy in AF with mitral stenosis is also controversial, and the result of BRIDGE trial which showed foregoing bridging therapy is noninferior to periprocedural heparin bridging to prevent arterial thromboembolism with lower risk of bleeding. In ESGE guidelines, AF with mitral stenosis is regarded as high risk of thromboembolism, but in APAGE/APSDE guidelines, it is regarded as low risk with no need for bridging therapy. As patients of nonvalvular AF with CHA2DS2VASc score >5 have a high risk of thromboembolism, bridging therapy has been recommended by APAGE/APSDE guidelines. In contrast, the cutoff of the same score is >2 in ASGE guidelines.,,
Although there are differences in the various guidelines, the basic concept is either there is a high or low risk of thromboembolism in the absence of anticoagulant, and the high-risk patients need bridging therapy by unfractionated heparin (UFH) (ASGE and APAGE/APSDE) or low-molecular-weight heparin (LMWH) (BSG/ESGE). The most recent guidelines are by APAGE/APSDE which has stratified patients according to the need for bridging therapy which is required obviously in high-risk patients [Table 4].,,
|Table 4: Risk stratification for discontinuation of warfarin therapy with respect to the requirement of heparin bringing|
Click here to view
Host's risk of bleeding
Incidence of gastrointestinal bleeding in the setting of acute coronary syndrome
Risk of bleeding from any site in the setting of ACS is between 3.2% and 9.1%, and majority of the life-threatening bleed are GI. Reported rates of GI bleeding in the setting of ACS are estimated to be 1%–3%, and those who develop GI bleed have a 4–7-fold increased risk of mortality.,,,, Abbas et al. reported bleeding rate of 2.3% and mortality of 10%. Increasing age, female sex, previous bleeding, and renal impairment are predictors of bleeding from any site after PCI according to GRACE study, whereas risk factors for GI bleed are age, prior history of ulcer, Helicobacter pylori infection, nonsteroidal anti-inflammatory drugs usage, sepsis, and mechanical ventilation.,
Among the antiplatelets, aspirin is ulcerogenic whereas clopidogrel is not. Hence, risk of GI bleeding with aspirin is more than clopidogrel alone, and similar risk with dual antiplatelets is more than aspirin alone. Interestingly, statins which are almost always used in the setting of ACS, lower risk of GI bleed probably by increasing gastric mucosal prostaglandin production.,
Minor bleeding is not uncommon during endoscopic procedures, but bleeding is considered to be clinically significant if hemoglobin falls by >2 g/dl or there is a need for blood transfusion and hospitalization. Bleeding can be immediate or delayed up to 2 weeks following the procedure. The odd's ratio of serious GI bleed with aspirin, clopidogrel, and dual antiplatelet therapy (DAPT) according to a population-based study is 1.9, 1.8, and 7.4, respectively.
Risk stratification of elective endoscopic procedures
Based on complexity and nature of therapeutic intervention, endoscopic procedures can be high risk (>1% risk of bleeding) or low risk (<1% risk of bleeding). These have been listed in [Table 5]. Low-risk procedures do not warrant discontinuation of antithrombotics (irrespective of type of agent except for warfarin if INR is supratherapeutic, i.e., >3.5). For high-risk procedures, anticoagulants and P2Y12 antagonists should be discontinued, and aspirin can be continued. In high-risk procedures such as colonoscopic polypectomy and endoscopic sphincterotomy, aspirin has been found to be safe.,, Few procedures have ultrahigh risk of bleeding such as endoscopic submucosal dissection (ESD) and endoscopic mucosal resection of large polyps (>2 cm) and aspirin should be stopped during these procedures as there is a high risk of hemorrhage with continued use of aspirin.,, Current APAGE/APSDE guidelines have added an additional ultrahigh-risk group which was not included in earlier ASGE guidelines although BSG-ESGE guidelines have recognized this very high-risk group but did not stratify this group [Table 1].,,
|Table 5: Classification of elective endoscopic procedures according to risk of bleeding|
Click here to view
| Timing Of Procedure|| |
Other than balancing risk of GI bleed/procedure and risk of thrombosis on discontinuation of antithrombotic agents, important factors to consider are the settings of endoscopy (elective or urgent). Yet another important fact to consider is timing of resumption of antithrombotic agents after endoscopic hemostasis. Various societies have developed different guidelines for the management of those patients. In this review, we shall stress on Asia-Pacific guidelines.
Single antiplatelet agent
Aspirin primarily used for secondary prevention of cardiovascular diseases in Asia-Pacific region including India reduces vascular events and deaths by one-third and one-sixth, respectively. Patients with ACS usually require DAPT as all intraplatelet pathways are not blocked by aspirin, a cyclooxygenase inhibitor. Other nonaspirin antiplatelets are used usually along with aspirin and are hence discussed in section of DAPT.
Emergency endoscopy should not be delayed in aspirin users. If emergency endoscopy is not available, then aspirin can be withheld. This is because the effect of aspirin usually lasts up to 7–9 days after cessation.
Resumption of aspirin
Aspirin should be started promptly after endoscopic hemostasis. APAGE/APSDE recommends resumption of aspirin 3–5 days after hemostasis. ESGE also recommends stopping aspirin for 3 days after treatment of high-risk stigmata during endoscopic hemostasis. Available evidence resumption of aspirin after nonvariceal upper GI bleed comes from a double-blind placebo-controlled trial done in Hong Kong by Sung et al. One hundred and fifty-six aspirin users with cardiovascular disease with actively bleeding peptic ulcers were randomized to resume aspirin or placebo immediately after endoscopic hemostasis. At 8 weeks, ten times all-cause mortality was noted in nonaspirin users compared to aspirin users. A thirty-day rebleeding rate was two times higher in aspirin group., Hence, resumption of aspirin after treatment of nonvariceal GI bleeding is critical as possibility of serious cardiovascular outcomes due to nonresumption of aspirin outweigh risk of rebleeding due to resumption of aspirin.
Role of platelet transfusion
ASGE guidelines recommend platelet transfusion for life-threatening GI bleed in patients on aspirin, but available evidence is on the contrary. In a retrospective cohort study, rebreeding rate was similar after platelet transfusion but associated with high mortality.
For low- and high-risk procedure, aspirin can be continued, but it has to be stopped prior to ultrahigh-risk procedures [Table 5].
Dual antiplatelet therapy
Given the high risk of stent thrombosis in initial 6 months after coronary stent placement, the APAGE/APSDE guidelines recommend discussion with cardiologist before stopping antiplatelet therapy., If both antiplatelets are stopped, the median time to stent thrombosis is as short as 7 days, whereas it is 122 days if only clopidogrel is stopped. This is the rationale of stopping clopidogrel alone. With higher prevalence (25%) of slow metabolizers of CYP2C19 in Asian population compared to Western population (5%), drug interaction of clopidogrel with high-dose proton-pump inhibitor cannot be ruled out., Although not validated, this represents another cause for stopping clopidogrel rather than aspirin in these settings.
Resuming clopidogrel and other P2Y12 inhibitors
Other P2Y12 inhibitors such as prasugrel (irreversible) and ticagrelor (reversible) are more potent and associated with higher bleeding complications. There is no head-to-head comparison of bleeding risk between prasugrel and ticagrelor. Among DAPTs, the comparative bleeding risk is as follows: prasugrel + aspirin > ticagrelor+ aspirin > clopidogrel + aspirin.,, The days by which platelet function returns to normal in prasugrel, clopidogrel, and ticagrelor are 7 days, 5 days, and 3–5 days. Hence, reinitiation of prasugrel and clopidogrel (both irreversible inhibitor) should be done after 5 days, whereas ticagrelor (reversible inhibitor) can be resumed after 2–3 days. There are no data on GI procedure risk with new antiplatelet agent vorapaxar, a protease-activated receptor 1 antagonist, which is not yet available in India.
Elective endoscopy on dual antiplatelet therapy
For low-risk procedures, stopping DAPT therapy is not recommended. For high-risk procedures stop P2Y12 inhibitors 5 days before endoscopy and continue aspirin and resume DAPT after adequate hemostasis. For ultrahigh-risk procedures, both antiplatelets should be stopped. For high-risk procedures, the management of antithrombotic therapy varies according to thrombotic risk category: very high, high, and moderate to low [Table 3]. As short period of triple antithrombotic therapy (DAPT plus anticoagulant) followed by 1 year of double therapy (DAPT or single antiplatelet and oral anticoagulant) is often used in patients with ACS/PCI and nonvalvular AF, the management of anticoagulants (warfarin and direct-acting oral anticoagulants (DOACs) is mentioned in [Table 3]. The status of anticoagulants and endoscopy procedures will be discussed later.
Stopping warfarin and reversal of anticoagulation
All the guidelines recommend stopping warfarin in case of serious life-threatening bleeding.,, Reversal of anticoagulation is recommended in all patients on warfarin according to irrespective of INR level according to ASGE guidelines, but APAGE/APSDE recommends reversal only if INR >2.5. The basis of this recommendation is a very high success rate of endoscopic hemostasis (>95%) if INR is between 1.5 and 2.5.,
The options of reversal are four-factor prothrombin complex concentrate (PCC) or fresh frozen plasma (FFP). The advantages of the former are faster onset of action, less fluid overload, lower infection risk, and no need for ABO mismatching. Four-factor PCC has to be combined with Vitamin K to replenish factor VII as it has a very short half-life (4 h). The optimal dose of Vitamin K for reversal is also an area of debate. ASGE recommends 5–10 mg of Vitamin K whereas APAGE/APSDE recommends low-dose Vitamin K (1–2.5 mg) based on finding of RCTs which shows that the optimal dose for reversal is 1–2.5 mg., Low dose is also recommended based on the fact that early initiation of warfarin therapy may be required in patients with high thromboembolic risk. In patients with high thromboembolic risk, heparin-bridging therapy should be started given the slow onset of action of warfarin after reinitiation. ESGE recommends LMWH for bridging therapy, whereas ASGE and APAGE/APSDE recommend UFH due to its shorter half-life (1–2 h compared to 4–5 h for LMWH) which allows rapid reversal in the event of rebleeding.
Resumption of warfarin
The thrombotic risk of individual patient dictates the optimal time of resumption of warfarin. Resuming warfarin at 7–30 days reduces thromboembolism risk significantly without increasing bleeding risk but resuming <7 days increases rebleeding risk by 2-fold. Hence, ESGE guidelines recommend to restart warfarin at 7–15 days following bleeding event. Whereas APAGE/APSDE guidelines recognize that early rebleeding risk significantly decreases after day 3, so early resumption of warfarin is recommended at day 3 in patients with high thromboembolic risk as time to re-anticoagulation may be prolonged.
Bridging therapy based on risk of thromboembolism
Already been discussed earlier in section of risk of thrombosis in prothrombotic states.
Direct-acting oral anticoagulants
Stopping direct-acting oral anticoagulants
The management of acute bleeding in patients on DOACs is covered in details in APAGE/APSDE guidelines, whereas specific recommendations are not provided by ASGE or ESGE guidelines.,,
For management in such situations, the following are to be considered.
Severity of bleeding: if bleeding is not life-threatening, then temporary discontinuation of DOACs will be sufficient with hemodynamic support. For life-threatening bleed, antidotes such as activated charcoal, monoclonal antibody against dabigatran (idarucizumab 5 gm), or dialysis in case of dabigatran (rest are nondialyzable) can be used.,,
- Timing of last DOAC intake: Activated charcoal is effective as antidote if given within the first 3 h as most DOACs have peak action at 3 h
- Creatinine clearance: All the DOACs are contraindicated for creatinine clearance below 15 ml/min. Dabigatran is contraindicated for creatinine clearance below 30 ml/min
- Pharmacokinetic properties of individual DOACs: DOACs have fast onset of action (1–4 h), with a half-life of 12 h. Eighty percent of dabigatran is eliminated by renal route, and hence, it is dialyzable whereas other DOACs are not. Most of the DOACs should be discontinued 2 days before high-risk endoscopic procedure, except for dabigatran for which time of discontinuation varies according to creatinine clearance [Table 2].
The role of FFP or four factor PCC in severe bleeding with DOACs is doubtful in view of the scarcity of clinical data.,
Measurement of anticoagulant activity of DOACs can be done by specific factor assays as recommended in ESGE guidelines but is not recommended by APAGE/APSDE due to nonavailability issues.,
Resumption of direct-acting oral anticoagulants after hemostasis
Early resumption without heparin bridging is recommended as these agents have short half-life (12 h) and fast onset of action (1–4 h). Concerns about early rebleeding should not defer the resumption of DOACs as most of the times rebleed can be controlled in a predictable way.
DOACs should be stopped only before high or ultrahigh-risk procedures at least 48 h before endoscopy (timing may vary according to creatinine clearance: CrCl) [Table 2]. Bridging anticoagulation is not warranted neither before nor after endoscopic hemostasis with resumption of DOACs after adequate hemostasis without undue delay.
For low-risk procedures, although ESGE guidelines recommend stopping morning dose of DOACs, APAGE/APSDE guidelines do not recommend stopping DOAC even on the day of procedure given very low risk of such procedures.,
Triple and double antithrombotic therapies
As discussed in section of DAPT, in patients with nonvalvular AF and ACS/PCI, a short period of triple antithrombotic (DAPT + 1 oral anticoagulant) followed by dual therapy (single antiplatelet + 1 oral anticoagulant) for up to 1 year is recommended. The European Society of Cardiology recommends to stop one of the antiplatelets during bleed with triple therapy and discontinuation of antiplatelet for bleed during dual therapy. In patients with nonvalvular AF and ACS/PCI and low risk of stroke, they recommend DAPT alone for 1 year without anticoagulant. The APAGE/APSDE guidelines recommend discussion with a cardiologist in this complex situation.
| Conclusion|| |
The literature of endoscopy in patients with antithrombotic is still evolving, and many of the recommendations by various societies are based on indirect evidence. The most recent APAGE/APSDE guidelines published in 2018 are developed specifically to meet the needs of Asia-Pacific region to manage patients on antithrombotic who need elective or emergency endoscopy given the higher incidence of nonvariceal upper GI bleed and more common performance of invasive endoscopic procedures such as ESD in this region. The comparison with other guidelines has been highlighted in [Table 6]. The main aim of this review was to simplify this complex subject of managing patients on antithrombotics requiring endoscopy which has been summarized in [Figure 1].
|Table 6: Comparison and major differences between the existing guidelines|
Click here to view
|Figure 1: Concise algorithmic management outline of patients on antiplatelet or antithrombotic therapy requiring urgent or elective endoscopy|
Click here to view
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Goodman LS, Brunton LL, Chabner B, Knollmann BC. Goodman & Gilman's Pharmacological Basis of Therapeutics. New York: McGraw-Hill; 2011.
Kasper DL, Fauci AS, Hauser SL, Longo DL, Jameson JL, Loscalzo J. Harrison's Principles of Internal Medicine. 19th
ed. New York: McGraw Hill Education; 2015.
Chan FK, Goh KL, Reddy N, Fujimoto K, Ho KY, Hokimoto S, et al.
Management of patients on antithrombotic agents undergoing emergency and elective endoscopy: Joint Asian Pacific Association of Gastroenterology (APAGE) and Asian pacific Society for Digestive Endoscopy (APSDE) practice guidelines. Gut 2018;67:405-17.
Hawn MT, Graham LA, Richman JS, Itani KM, Henderson WG, Maddox TM, et al.
Risk of major adverse cardiac events following noncardiac surgery in patients with coronary stents. JAMA 2013;310:1462-72.
Fleisher LA, Fleischmann KE, Auerbach AD, Barnason SA, Beckman JA, Bozkurt B, et al.
2014 ACC/AHA guideline on perioperative cardiovascular evaluation and management of patients undergoing noncardiac surgery: A report of the American College of Cardiology/American Heart Association task force on practice guidelines. J Am Coll Cardiol 2014;64:e77-137.
Douketis JD, Spyropoulos AC, Spencer FA, Mayr M, Jaffer AK, Eckman MH, et al.
Perioperative management of antithrombotic therapy: Antithrombotic therapy and prevention of thrombosis, 9th
ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest 2012;141:e326S-50S.
Douketis JD, Healey JS, Brueckmann M, Eikelboom JW, Ezekowitz MD, Fraessdorf M, et al.
Perioperative bridging anticoagulation during dabigatran or warfarin interruption among patients who had an elective surgery or procedure. Substudy of the RE-LY trial. Thromb Haemost 2015;113:625-32.
Douketis JD, Spyropoulos AC, Kaatz S, Becker RC, Caprini JA, Dunn AS, et al.
Perioperative bridging anticoagulation in patients with atrial fibrillation. N Engl J Med 2015;373:823-33.
Veitch AM, Vanbiervliet G, Gershlick AH, Boustiere C, Baglin TP, Smith LA, et al.
Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British society of gastroenterology (BSG) and European society of gastrointestinal endoscopy (ESGE) guidelines. Gut 2016;65:374-89.
ASGE Standards of Practice Committee, Acosta RD, Abraham NS, Chandrasekhara V, Chathadi KV, Early DS, et al.
The management of antithrombotic agents for patients undergoing GI endoscopy. Gastrointest Endosc 2016;83:3-16.
Foley P, Foley S, Kinnaird T, Anderson RA. Clinical review: Gastrointestinal bleeding after percutaneous coronary intervention: A deadly combination. QJM 2008;101:425-33.
Leon MB, Baim DS, Popma JJ, Gordon PC, Cutlip DE, Ho KK, et al.
Aclinical trial comparing three antithrombotic-drug regimens after coronary-artery stenting. Stent anticoagulation restenosis study investigators. N Engl J Med 1998;339:1665-71.
Mehta SR, Yusuf S, Peters RJ, Bertrand ME, Lewis BS, Natarajan MK, et al.
Effects of pretreatment with clopidogrel and aspirin followed by long-term therapy in patients undergoing percutaneous coronary intervention: The PCI-CURE study. Lancet 2001;358:527-33.
Moscucci M, Fox KA, Cannon CP, Klein W, López-Sendón J, Montalescot G, et al.
Predictors of major bleeding in acute coronary syndromes: The Global Registry of acute Coronary Events (GRACE). Eur Heart J 2003;24:1815-23.
Al-Mallah M, Bazari RN, Jankowski M, Hudson MP. Predictors and outcomes associated with gastrointestinal bleeding in patients with acute coronary syndromes. J Thromb Thrombolysis 2007;23:51-5.
Abbas AE, Brodie B, Dixon S, Marsalese D, Brewington S, O'Neill WW, et al.
Incidence and prognostic impact of gastrointestinal bleeding after percutaneous coronary intervention for acute myocardial infarction. Am J Cardiol 2005;96:173-6.
Atar S, Cannon CP, Murphy SA, Rosanio S, Uretsky BF, Birnbaum Y. Statins are associated with lower risk of gastrointestinal bleeding in patients with unstable coronary syndromes: Analysis of the orbofiban in patients with unstable coronary syndromes-thrombolysis in myocardial infarction 16 (OPUS-TIMI 16) trial. Am Heart J 2006;151:976.e1-6.
Hallas J, Dall M, Andries A, Andersen BS, Aalykke C, Hansen JM, et al.
Use of single and combined antithrombotic therapy and risk of serious upper gastrointestinal bleeding: Population based case-control study. BMJ 2006;333:726.
Hui AJ, Wong RM, Ching JY, Hung LC, Chung SC, Sung JJ, et al.
Risk of colonoscopic polypectomy bleeding with anticoagulants and antiplatelet agents: Analysis of 1657 cases. Gastrointest Endosc 2004;59:44-8.
Nelson DB, Freeman ML. Major hemorrhage from endoscopic sphincterotomy: Risk factor analysis. J Clin Gastroenterol 1994;19:283-7.
Yousfi M, Gostout CJ, Baron TH, Hernandez JL, Keate R, Fleischer DE, et al.
Postpolypectomy lower gastrointestinal bleeding: Potential role of aspirin. Am J Gastroenterol 2004;99:1785-9.
Cho SJ, Choi IJ, Kim CG, Lee JY, Nam BH, Kwak MH, et al.
Aspirin use and bleeding risk after endoscopic submucosal dissection in patients with gastric neoplasms. Endoscopy 2012;44:114-21.
Burgess NG, Metz AJ, Williams SJ, Singh R, Tam W, Hourigan LF, et al.
Risk factors for intraprocedural and clinically significant delayed bleeding after wide-field endoscopic mucosal resection of large colonic lesions. Clin Gastroenterol Hepatol 2014;12:651-61.
Metz AJ, Bourke MJ, Moss A, Williams SJ, Swan MP, Byth K, et al.
Factors that predict bleeding following endoscopic mucosal resection of large colonic lesions. Endoscopy 2011;43:506-11.
Sung JJ, Lau JY, Ching JY, Wu JC, Lee YT, Chiu PW, et al.
Continuation of low-dose aspirin therapy in peptic ulcer bleeding: A randomized trial. Ann Intern Med 2010;152:1-9.
Zakko L, Rustagi T, Douglas M, Laine L. No benefit from platelet transfusion for gastrointestinal bleeding in patients taking antiplatelet agents. Clin Gastroenterol Hepatol 2017;15:46-52.
Kukreja N, Onuma Y, Garcia-Garcia HM, Daemen J, van Domburg R, Serruys PW, et al.
The risk of stent thrombosis in patients with acute coronary syndromes treated with bare-metal and drug-eluting stents. JACC Cardiovasc Interv 2009;2:534-41.
Eisenberg MJ, Richard PR, Libersan D, Filion KB. Safety of short-term discontinuation of antiplatelet therapy in patients with drug-eluting stents. Circulation 2009;119:1634-42.
Yamada S, Onda M, Kato S, Matsuda N, Matsuhisa T, Yamada N, et al.
Genetic differences in CYP2C19 single nucleotide polymorphisms among four Asian populations. J Gastroenterol 2001;36:669-72.
Wallentin L, Becker RC, Budaj A, Cannon CP, Emanuelsson H, Held C, et al.
Ticagrelor versus clopidogrel in patients with acute coronary syndromes. N Engl J Med 2009;361:1045-57.
Wiviott SD, Braunwald E, McCabe CH, Montalescot G, Ruzyllo W, Gottlieb S, et al.
Prasugrel versus clopidogrel in patients with acute coronary syndromes. N Engl J Med 2007;357:2001-15.
Zeymer U, Hochadel M, Lauer B, Kaul N, Wöhrle J, Andresen D, et al.
Use, efficacy and safety of prasugrel in patients with ST segment elevation myocardial infarction scheduled for primary percutaneous coronary intervention in clinical practice. Results of the prospective ATACS-registry. Int J Cardiol 2015;184:122-7.
Choudari CP, Rajgopal C, Palmer KR. Acute gastrointestinal haemorrhage in anticoagulated patients: Diagnoses and response to endoscopic treatment. Gut 1994;35:464-6.
Wolf AT, Wasan SK, Saltzman JR. Impact of anticoagulation on rebleeding following endoscopic therapy for nonvariceal upper gastrointestinal hemorrhage. Am J Gastroenterol 2007;102:290-6.
Karaca MA, Erbil B, Ozmen MM. Use and effectiveness of prothrombin complex concentrates vs. fresh frozen plasma in gastrointestinal hemorrhage due to warfarin usage in the ED. Am J Emerg Med 2014;32:660-4.
Patel RJ, Witt DM, Saseen JJ, Tillman DJ, Wilkinson DS. Randomized, placebo-controlled trial of oral phytonadione for excessive anticoagulation. Pharmacotherapy 2000;20:1159-66.
Crowther MA, Julian J, McCarty D, Douketis J, Kovacs M, Biagoni L, et al.
Treatment of warfarin-associated coagulopathy with oral vitamin K: A randomised controlled trial. Lancet 2000;356:1551-3.
Eikelboom JW, Hankey GJ. Low molecular weight heparins and heparinoids. Med J Aust 2002;177:379-83.
Lee JK, Kang HW, Kim SG, Kim JS, Jung HC. Risks related with withholding and resuming anticoagulation in patients with non-variceal upper gastrointestinal bleeding while on warfarin therapy. Int J Clin Pract 2012;66:64-8.
Wang X, Mondal S, Wang J, Tirucherai G, Zhang D, Boyd RA, et al.
Effect of activated charcoal on apixaban pharmacokinetics in healthy subjects. Am J Cardiovasc Drugs 2014;14:147-54.
Pollack CV Jr., Reilly PA, van Ryn J, Eikelboom JW, Glund S, Bernstein RA, et al.
Idarucizumab for dabigatran reversal – Full cohort analysis. N Engl J Med 2017;377:431-41.
Khadzhynov D, Wagner F, Formella S, Wiegert E, Moschetti V, Slowinski T, et al.
Effective elimination of dabigatran by haemodialysis. A phase I single-centre study in patients with end-stage renal disease. Thromb Haemost 2013;109:596-605.
Eerenberg ES, Kamphuisen PW, Sijpkens MK, Meijers JC, Buller HR, Levi M, et al.
Reversal of rivaroxaban and dabigatran by prothrombin complex concentrate: A randomized, placebo-controlled, crossover study in healthy subjects. Circulation 2011;124:1573-9.
Halvorsen S, Storey RF, Rocca B, Sibbing D, Ten Berg J, Grove EL, et al.
Management of antithrombotic therapy after bleeding in patients with coronary artery disease and/or atrial fibrillation: Expert consensus paper of the European Society of Cardiology Working Group on Thrombosis. Eur Heart J 2017;38:1455-62.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]