Idarucizumab for Dabigatran Reversal in the Management of Patients With Gastrointestinal Bleeding.

BACKGROUND: Although dabigatran has a favorable risk-benefit profile compared with vitamin K antagonist therapy for venous thromboembolism and nonvalvular atrial fibrillation, major bleeding events, including gastrointestinal (GI) bleeding, may occur. Therefore, our aim was to provide insights into the efficacy and safety of idarucizumab for urgent dabigatran reversal in patients with major GI bleeding. METHODS: Patients with uncontrollable GI bleeding requiring reversal were enrolled from June 2014 through July 2016 in the RE-VERSE AD study (Reversal of Dabigatran Anticoagulant Effect With Idarucizumab), a prospective, multicenter, open-label study of idarucizumab, and were followed up for 90 days for primary and secondary outcomes. Patients were to receive a 5-g dose of intravenous idarucizumab, administered as 2 bolus infusions of 2.5 g no more than 15 minutes apart. The primary end point was the maximum reversal of dabigatran anticoagulation within 4 hours after administration of idarucizumab as measured by the dabigatran-specific assays diluted thrombin time and ecarin clotting time. Further end points included investigator-reported bleeding cessation within the first 24 hours and incidence of rebleeding, thromboembolic events, or mortality. RESULTS: GI bleeding occurred in 137 patients enrolled in RE-VERSE AD, of which 84% was adjudicated as major or life-threatening, 48 (35.0%) was upper GI tract in origin, 43 (31.4%) was lower GI in origin, and 46 (33.6%) was either both or unknown. Complete reversal of dabigatran was observed in 118 of 121 patients (97.5%) with an elevated diluted thrombin time at presentation and 95 of 131 patients (72.5%) with an elevated ecarin clotting time and was similar for upper and lower GI bleeding. Bleeding cessation within 24 hours was reported in 92 of 134 evaluable patients (68.7%) after a median duration of 2.4 hours (interquartile range, 2.0-3.9 hours). During the 90-day follow-up, 6 patients (4.4%) had a postreversal thromboembolic event, and 20 patients (14.6%) died. CONCLUSIONS: Idarucizumab showed a rapid and complete reversal of dabigatran activity in nearly all patients presenting with GI bleeding, facilitating emergency patient care without the additional presence of anticoagulation. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02104947.

Gastrointestinal Bleeding With Edoxaban Versus Warfarin: Results From the ENGAGE AF-TIMI 48 Trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis In Myocardial Infarction).

BACKGROUND: The ENGAGE AF-TIMI 48 trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis In Myocardial Infarction) compared higher-dose edoxaban regimen (HD-ER) and lower-dose edoxaban regimen with well-managed warfarin in 21 105 patients with atrial fibrillation. The risk factors and clinical impact of gastrointestinal bleeding (GIB) in this trial have not been described in detail. METHODS AND RESULTS: This analysis was undertaken to identify risk factors for major GIB (MGIB) and compare the severity and outcomes of GIB with edoxaban and warfarin. During 2.8 years mean follow-up, there were 579 MGIB (1.22% per year), of which 63 were life-threatening or fatal (0.13% per year). Male sex, increased age, prior GIB, concomitant aspirin, lower baseline hemoglobin, renal dysfunction, and higher HAS-BLED and CHADS2 scores were independently associated with the risk of MGIB. Whereas the annual rate of MGIB was higher with HD-ER than with warfarin (1.53% and 1.25%, respectively; hazard ratio, 1.23; 95% confidence interval, 1.02-1.48; P=0.033), the annual rates of life-threatening or fatal GIB were similar (0.15% and 0.18%, respectively). Several indicators of more severe GIB, including hemodynamic instability, hospitalization, ≥ 4 U transfusion, and hemoglobin loss ≥5 g/dL, were similar with HD-ER and warfarin, whereas surgery required to manage bleeding was less frequent with HD-ER. Lower-dose edoxaban regimen, which achieved 50% lower trough edoxaban levels, was associated with significantly less MGIB than warfarin. CONCLUSIONS: MGIB occurred more frequently with HD-ER than warfarin. The rates of life-threatening or fatal GIB were low and similar with both HD-ER and warfarin. Clinical outcomes were generally favorable. The correlation between dose, trough edoxaban level, and the risk of GIB risk suggests GIB is exposure-related. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT00781391.

Locations and Mucosal Lesions Responsible for Major Gastrointestinal Bleeding in Patients on Warfarin or Dabigatran.

BACKGROUND AND AIM: Different oral anticoagulants may be associated with gastrointestinal bleeding (GIB) from different locations or mucosal lesions. We aimed to test this hypothesis. METHODS: Two blinded gastroenterologists independently analyzed source documents from the randomized evaluation of long-term anticoagulant therapy (RE-LY) trial of dabigatran 150 mg BID (D150), dabigatran 110 mg BID (D110) versus warfarin in non-valvular atrial fibrillation (NVAF). RESULTS: Major GIB events (total n = 546) and life-threatening GIB events (n = 258) were more common with D150 versus warfarin (RR 1.57 [1.28-1.92] and RR 1.62 [1.20-2.18], respectively) and similar for D110 compared to warfarin (RR 1.11 [0.89-1.38] and RR 1.16 [0.84-1.61], respectively). Fatal bleeding was similarly rare across treatment groups. Lower GI major bleeding and life-threatening bleeding were more common with D150 compared to warfarin (RR 2.23 [1.47, 3.38] and RR 2.64 [1.36, 5.13], respectively) and with D110 compared to warfarin (RR 1.78 [1.16, 2.75] and RR 2.00 [1.00, 4.00], respectively). MGIB from colonic angiodysplasia was increased with dabigatran versus warfarin (P < 0.01 for both dose comparisons). Subacute and chronic MGIB events were more common with D150 than with warfarin (RR 1.72 [1.06, 2.78] and RR 1.66 [1.12, 2.45], respectively), as were hematochezia or melena (RR 1.67 [1.18, 2.36] and RR 1.72 [1.20, 2.47], respectively). CONCLUSIONS: In a chronic NVAF population, D150 but not D110 is associated with increased major and life-threatening GI bleeding in comparison with warfarin. At both dabigatran doses, increased bleeding from the colorectum, in particular from angiodysplasia, is seen.

Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation: part 1.

Patients with atrial fibrillation (AF) have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants (OAC). Recently, four non-vitamin-K oral anticoagulants (NOACs) were compared with warfarin in large randomized trials for the prevention of stroke and systemic embolism. Today's clinician is faced with the difficult task of selecting a suitable OAC for a patient with a particular clinical profile or a particular pattern of risk factors and concomitant diseases. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. NOACs for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In the first of a two-part review, we discuss the choice of NOAC for stroke prevention in the following subgroups of patients with AF: (i) stable coronary artery disease or peripheral artery disease, including percutaneous coronary intervention with stenting and triple therapy; (ii) cardioversion, ablation and anti-arrhythmic drug therapy; (iii) mechanical valves and rheumatic valve disease, (iv) patients with time in therapeutic range of >70% on warfarin; (v) patients with a single stroke risk factor (CHA2DS2VASc score of 1 in males, 2 in females); and (vi) patients with a single first episode of paroxysmal AF. Although there are no major differences in terms of efficacy and safety between the NOACs for some clinical scenarios, in others we are able to suggest that particular drugs and/or doses be prioritized for anticoagulation.

Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation: part 2.

The choice of oral anticoagulant (OAC) for patients with atrial fibrillation (AF) may be influenced by individual clinical features or by patterns of risk factors and comorbidities. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. non-vitamin K oral anticoagulants (NOACs) for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In addition, we discuss the timing of initiation of anticoagulation. In the second of a two-part review, we discuss the use of NOAC for stroke prevention in the following subgroups of patients with AF: (vii) secondary stroke prevention in patients after stroke or transient ischaemic attack (TIA), (viii) patients with acute stroke requiring thrombolysis or thrombectomy, (ix) those initiating or restarting OAC treatment after stroke or TIA, (x) those with renal impairment on dialysis, (xi) the elderly, (xii) those at high risk of gastrointestinal bleeding, and (xiii) those with hypertension. In addition, we discuss adherence and compliance. Finally, we present a summary of treatment suggestions. In specific subgroups of patients with AF, evidence supports the use of particular NOACs and/or particular doses of anticoagulant. The appropriate choice of treatment for these subgroups will help to promote optimal clinical outcomes.

Major Gastrointestinal Bleeding Often Is Caused by Occult Malignancy in Patients Receiving Warfarin or Dabigatran to Prevent Stroke and Systemic Embolism From Atrial Fibrillation.

BACKGROUND & AIMS: Gastrointestinal (GI) bleeding in patients receiving anticoagulation agents can be caused by occult malignancies. We investigated the proportions and features of major GI bleeding (MGIB) events related to occult GI cancers in patients receiving anticoagulation therapy. METHODS: We analyzed data from the Randomized Evaluation of Long Term Anticoagulant Therapy study (conducted between December 2005 and March 2009 in 951 clinical centers in 44 countries worldwide), which compared the abilities of dabigatran vs warfarin to prevent stroke and systemic embolism in 18,113 patients with atrial fibrillation. Two blinded gastroenterologists independently reviewed source documents of MGIB events (n = 595) that occurred during the study period. We collected data on MGIB events caused by previously unidentified GI malignancies, and compared characteristics of MGIB events in patients who received dabigatran vs warfarin (primary end point), and in patients with bleeding from cancer, vs patients bleeding from a nonmalignant or unidentified source. RESULTS: Of 546 unique MGIB events, 44 (8.1%) were found to be from GI cancers (34 of 398 MGIB events in dabigatran users and 10 of 148 MGIB events in warfarin users; P = .60). Colorectal cancer accounted for 35 of 44 of all cancers identified. There were more colorectal cancer-associated MGIB events in the dabigatran group (30 of 34) than in the warfarin group (5 of 10) (P = .02), but more gastric cancer-associated MGIB events in the warfarin group (5 of 10) than in the dabigatran group (1 of 34) (P = .001). There were no differences in the short-term outcomes of cancer-related MGIB events in the dabigatran vs the warfarin group, but 75% of all cancer-related MGIB events required at least 1 blood transfusion and the mean hospital stay was 10.1 days. Compared with MGIB events from a nonmalignant or unidentified source, MGIB from cancer occurred sooner (343.0 vs 223.1 d; P = .003), but the bleeding was more likely to be chronic (for >7 d) (27.3% vs 63.6%; P < .001). CONCLUSIONS: In evaluating data from a study of the effects of anticoagulation therapy, we found approximately 1 of every 12 MGIB events to be related to an occult cancer. Approximately two thirds of cancer-related MGIB presents with chronic bleeding, and morbidity, and resource utilization is high.

Efficacy of prothrombin complex concentrates for the emergency reversal of dabigatran-induced anticoagulation.

Dabigatran is effective in decreasing the risk of ischaemic stroke in patients with atrial fibrillation. However, like all anticoagulants, it is associated with a risk of bleeding. In cases of trauma or emergency surgery, emergency reversal of dabigatran-induced anticoagulation may be required. A specific reversal agent for dabigatran, idarucizumab, has been approved by the US Food and Drug Administration. Alternative reversal agents are available, such as prothrombin complex concentrates (PCCs) and activated PCCs (aPCCs). In this review we evaluate the role of PCCs and aPCCs in the reversal of dabigatran anticoagulation and consider which tests are appropriate for monitoring coagulation in this setting. Pre-clinical studies, small clinical studies and case reports indicate that PCCs and aPCCs may be able to reverse dabigatran-induced anticoagulation in a dose-dependent manner. However, dosing based on coagulation parameters can be difficult because available assays may not provide adequate sensitivity and specificity for measuring anticoagulation induced by dabigatran or the countering effects of PCCs/aPCCs. In addition, PCCs or aPCCs can potentially provoke thromboembolic complications. Despite these limitations and the fact that PCCs and aPCCs are not yet licensed for dabigatran reversal, their use appears to be warranted in patients with life-threatening haemorrhage if idarucizumab is not available.

Large Sessile Serrated Polyps Can Be Safely and Effectively Removed by Endoscopic Mucosal Resection.

BACKGROUND & AIMS: As many as 50% of large sessile serrated adenomas/polyps (SSPs) are removed incompletely, which is significant because SSPs have been implicated in the development of interval cancers. It is unclear if endoscopic mucosal resection (EMR) is an optimal method for removal of SSPs. We assessed the efficacy and safety of removal of SSPs 10 mm and larger using a standardized inject-and-cut EMR technique. METHODS: We performed a retrospective analysis of colonoscopy data, collected over 7 years (2007-2013) at 2 centers, from 199 patients with proximal colon SSPs 10 mm and larger (251 polyps) removed by EMR by 4 endoscopists. The primary outcome measure was local recurrence. The secondary outcome measure was safety. RESULTS: At the index colonoscopy, patients had a median of 1 serrated lesion (range, 1-12) and 1 nonserrated neoplastic lesion (range, 0-15). The mean SSP size was 15.9 ± 5.3 mm; most were superficially elevated (84.5%) and located in the ascending colon (51%), and 3 SSPs (1.2%) had dysplasia. Surveillance colonoscopies were performed on 138 patients (69.3%) over a mean follow-up period of 25.5 ± 17.4 months. Of these patients, 5 had local recurrences (3.6%; 95% confidence interval, 0.5%-6.7%), detected after 17.8 ± 15.4 months, with a median size of 4 mm. No patients developed postprocedural bleeding, perforation, or advanced colon cancer, or had a death related to the index colorectal lesion during the study period. CONCLUSIONS: Inject-and-cut EMR is a safe and effective technique for the resection of SSPs. Less than 5% of patients have a local recurrence, which is usually small and can be treated endoscopically.

Does Better Specimen Orientation and a Simplified Grading System Promote More Reliable Histologic Interpretation of Serrated Colon Polyps in the Community Practice Setting? Results of a Nationwide Study.

INTRODUCTION: Colonoscopic surveillance guidelines for serrated polyps (SPs) are predicated upon the histologic characteristics of the index polyp. However, discrimination between SP subtypes [hyperplastic polyps vs. sessile serrated adenoma/polyps (SSA/P)] is often unreliable. MATERIALS AND METHODS: We studied the impact of (1) a novel tissue orientation method, performed in the endoscopy laboratory, whereby polyps are flattened in a small paper envelope immediately after resection (modified protocol); and (2) 2012 consensus-modified criteria (CM-2012). These interventions were compared with conventional tissue-handling protocol (CP) and traditional 2008 World Health Organization criteria (WHO). Twenty blinded community pathologists from around the United States scored 100, independent, 0.5 to 2.0 cm, proximal colonic SPs randomly selected from a 2-site tissue section archive. We compared interobserver agreement and diagnostic grading. RESULTS: Interobserver agreement was higher using CM-2012 than WHO criteria (absolute agreement: 13% vs. 4%, P<0.01; 75% agreement: 54% vs. 38%, P<0.01). Interobserver agreement was higher with the modified protocol than with CP (WHO absolute agreement: 6% vs. 2%, P>0.05; WHO 75% agreement: 46% vs. 30%, P>0.05, and CM-2012 absolute agreement: 20% vs. 6%, P=0.07; CM-2012 75% agreement: 66% vs. 42%, P=0.03). Compared with WHO, use of CM-2012 criteria resulted in fewer diagnoses of "indeterminate"; more diagnoses of SSA/P (P<0.01); and "upgraded" the diagnosis from hyperplastic polyps to SSA/P in approximately 7% of cases. These observations were independent of polyp size, patient gender, and study site. CONCLUSIONS: Simple enhancements to postresection SP handling and diagnostic criteria markedly improve interobserver agreement of SP diagnosis among nongastrointestinal community pathologists. This finding, if confirmed, has important implications for SP colonoscopy surveillance guidelines.

Chromoendoscopy Is More Effective Than Standard Colonoscopy in Detecting Dysplasia During Long-term Surveillance of Patients With Colitis.

BACKGROUND & AIMS: Patients with colitis have an increased risk of colorectal cancer, compared with persons without colitis. Many studies have shown chromoendoscopy (CE) to be superior to standard methods of detecting dysplasia in patients with colitis at index examination. We performed a prospective, longitudinal study to compare standard colonoscopy vs CE in detecting dysplasia in patients with inflammatory bowel diseases in a surveillance program. METHODS: We analyzed data from 68 patients (44 men, 24 women) diagnosed with ulcerative colitis (n = 55) or Crohn's disease (n = 13) at Mount Sinai Medical Center from September 2005 through October 2011. The patients were followed from June 2006 through October 2011 (median, 27.8 months); each patient was analyzed by random biopsy, targeted white light examination (WLE), and CE. Specimens were reviewed by a single blinded pathologist. The 3 methods were compared by using the generalized estimating equations method, and the odds ratios (ORs) for detection of dysplasia were calculated (primary outcome). Time to colectomy was analyzed by using the Cox model. RESULTS: In the 208 examinations conducted, 44 dysplastic lesions were identified in 24 patients; 6 were detected by random biopsy, 11 by WLE, and 27 by CE. Ten patients were referred for colectomy, and no carcinomas were found. At any time during the study period, CE (OR, 5.4; 95% confidence interval [CI], 2.9-9.9) and targeted WLE (OR, 2.3; 95% CI, 1.0-5.3) were more likely than random biopsy analysis to detect dysplasia. CE was superior to WLE (OR, 2.4; 95% CI, 1.4-4.0). Patients identified as positive for dysplasia were more likely to need colectomy (hazard ratio, 12.1; 95% CI, 3.2-46.2). CONCLUSIONS: In a prospective study of 68 patients with inflammatory bowel diseases, CE was superior to random biopsy or WLE analyses in detecting dysplasia in patients with colitis during an almost 28-month period. A negative result from CE examination was the best indicator of a dysplasia-free outcome, whereas a positive result was associated with earlier referral for colectomy.

Accuracy of capsule colonoscopy in detecting colorectal polyps in a screening population.

BACKGROUND & AIMS: Capsule colonoscopy is a minimally invasive imaging method. We measured the accuracy of this technology in detecting polyps 6 mm or larger in an average-risk screening population. METHODS: In a prospective study, asymptomatic subjects (n = 884) underwent capsule colonoscopy followed by conventional colonoscopy (the reference) several weeks later, with an endoscopist blinded to capsule results, at 10 centers in the United States and 6 centers in Israel from June 2011 through April 2012. An unblinded colonoscopy was performed on subjects found to have lesions 6 mm or larger by capsule but not conventional colonoscopy. RESULTS: Among the 884 subjects enrolled, 695 (79%) were included in the analysis of capsule performance for all polyps. There were 77 exclusions (9%) for inadequate cleansing and whole-colon capsule transit time fewer than 40 minutes, 45 exclusions (5%) before capsule ingestion, 15 exclusions (2%) after ingestion and before colonoscopy, and 15 exclusions (2%) for site termination. Capsule colonoscopy identified subjects with 1 or more polyps 6 mm or larger with 81% sensitivity (95% confidence interval [CI], 77%-84%) and 93% specificity (95% CI, 91%-95%), and polyps 10 mm or larger with 80% sensitivity (95% CI, 74%-86%) and 97% specificity (95% CI, 96%-98%). Capsule colonoscopy identified subjects with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity (95% CI, 82%-93) and 82% specificity (95% CI, 80%-83%), and 10 mm or larger with 92% sensitivity (95% CI, 82%-97%) and 95% specificity (95% CI, 94%-95%). Sessile serrated polyps and hyperplastic polyps accounted for 26% and 37%, respectively, of false-negative findings from capsule analyses. CONCLUSIONS: In an average-risk screening population, technically adequate capsule colonoscopy identified individuals with 1 or more conventional adenomas 6 mm or larger with 88% sensitivity and 82% specificity. Capsule performance seems adequate for patients who cannot undergo colonoscopy or who had incomplete colonoscopies. Additional studies are needed to improve capsule detection of serrated lesions. Clinicaltrials.gov number: NCT01372878.

A simple tissue-handling technique performed in the endoscopy suite improves histologic section quality and diagnostic accuracy for serrated polyps.

BACKGROUND AND STUDY AIMS: Surveillance intervals after colonoscopic resection of serrated polyps are partially predicated on the histology of the polyp(s) removed during the index exam. Histologic discrimination between sessile serrated adenomas/polyps (SSA/P) and hyperplastic polyps is challenging. We devised and tested a simple tool--an envelope--that gastroenterologists can integrate into routine colonoscopy practice to address this problem. METHODS: In the "modified protocol," immediately after polypectomy each serrated polyp was flattened and enclosed in a paper envelope before being placed in formalin. In the pathology laboratory, each polyp was sectioned after processing. A two-site, prospective, randomized, single-blinded trial was performed to compare this modified protocol with the conventional protocol. Serrated polyps located proximal to the splenic flexure and 5-20 mm in diameter were included. A novel orientation score that measured the number of well-oriented crypts per unit area of polyp (higher orientation score = better orientation) was validated. Orientation score, SSA/P diagnosis rate, and inter-pathologist agreement were measured. RESULTS: A total of 375 polyps were enrolled, of which 264 were identified for analysis. The mean orientation scores in the modified and conventional protocol groups were 3.11 and 1.13, respectively (P < 0.0001). SSA/Ps were diagnosed in 103/135 cases (76.3%) in the modified protocol group vs. 54/129 (41.9%) in the conventional protocol group (P < 0.0001). Inter-pathologist agreement was higher with the modified than the conventional protocol (77.0% vs. 62.8%; P = 0.015). CONCLUSION: Standard polyp handling techniques may be sub-optimal for interpretation of serrated polyps resected at colonoscopy, and may lead to inadvertent histologic "under-grading" of many lesions. Our intervention improved histopathologic interpretation and increased the SSA/P diagnosis rate.

Analysis of upper gastrointestinal adverse events among patients given dabigatran in the RE-LY trial.

BACKGROUND & AIMS: Dabigatran is an oral and direct inhibitor of thrombin. In a study of patients with atrial fibrillation (the RE-LY trial), twice as many subjects given dabigatran reported dyspepsia-like symptoms compared with those given warfarin (controls). We analyzed data from this trial to quantify upper gastrointestinal nonbleeding adverse events (NB-UGI AEs). METHODS: We analyzed the AE database from the RE-LY trial (18,113 subjects) and assigned NB-UGI AEs to 4 groups: those associated with gastroesophageal reflux (GERD), upper abdominal pain and dyspepsia, dysmotility, or gastroduodenal injury. We analyzed frequency, timing, and severity, and clinical variables associated with NB-UGI AEs. RESULTS: NB-UGI AEs occurred in 16.9% of subjects given dabigatran and in 9.4% of controls (relative risk [RR], 1.81; 95% confidence interval [CI], 1.66%-1.97%; P < .001). Rates of AEs were not associated with the dose of dabigatran. Among subjects with any UGI symptom who were given dabigatran (n = 2045), symptoms were rated as mild in 46.3%, moderate in 44.8%, and severe in 8.9%; these values were similar to those of controls. GERD-associated NB-UGI AEs were most frequent among the 4 groups (compared with controls, RR, 3.71; 95% CI, 2.98%-4.62%; P < .001). Four percent of subjects stopped taking dabigatran because of NB-UGI AEs (most within 3 months of starting therapy), compared with 1.7% of controls (RR, 2.34; 95% CI, 1.90%-2.88%; P < .001). NB-UGI AEs slightly increased risk of major GI bleeding among subjects given dabigatran and controls (6.8% vs 2.3%, P < .001). CONCLUSIONS: Among patients given dabigatran for atrial fibrillation, NB-UGI AEs are generally mild or moderate; 4% stopped taking the drug over a median of 21.7 months. The greatest increase was in GERD-type NB-UGI AEs. These observations should guide management and prevention strategies.