Ansell, Jack

BackgroundOral anticoagulation (OAC) therapy is associated with increased periprocedural risks after cardiac implantable electronic device (CIED) implantation. Patterns of anticoagulation management involving non–vitamin K antagonist oral anticoagulants (NOACs) have not been characterized.HypothesisAnticoagulation strategies and outcomes differ by anticoagulant type in patients undergoing CIED implantation.MethodsUsing the nationwide Outcomes Registry for Better Informed Treatment of Atrial Fibrillation, we assessed how atrial fibrillation (AF) patients undergoing CIED implantation were cared for and their subsequent outcomes. Outcomes were compared by oral anticoagulant therapy (none, warfarin, or NOAC) as well as by anticoagulation interruption status.ResultsAmong 9129 AF patients, 416 (5%) underwent CIED implantation during a median follow‐up of 30 months (interquartile range, 24–36). Of these, 60 (14%) had implantation on a NOAC. Relative to warfarin therapy, those on a NOAC were younger (70.5 years [range, 65–77.5 years] vs 77 years [range, 70–82 years]), had less valvular heart disease (15.0% vs 31.3%), higher creatinine clearance (67.3 [range, 59.7–99.0] vs 65.8 [range, 50.0–91.6]), were more likely to have persistent AF (26.7% vs 22.9%), and use concomitant aspirin (51.7% vs 35.2%). OAC therapy was commonly interrupted for CIED in 64% (n = 183 of 284) of warfarin patients and 65% (n = 39 of 60) of NOAC patients. Many interrupted patients received intravenous bridging anticoagulation: 33/183 (18%) interrupted warfarin and 4/39 (10%) interrupted NOAC patients. Thirty‐day periprocedure bleeding and stroke adverse events were infrequent.ConclusionsManagement of anticoagulation among AF patients undergoing CIED implantation is highly variable, with OAC being interrupted in more than half of both warfarin‐ and NOAC‐treated patients. Bleeding and stroke events were infrequent in both warfarin and NOAC‐treated patients.

Abstract Aims The presence of cancer can complicate treatment choices for patients with atrial fibrillation (AF) increasing both the risk of thrombotic and bleeding events. Methods and results Using data from Outcomes Registry for Better Informed Treatment of Atrial Fibrillation, we aimed to characterize AF patients with cancer, to describe their management and to assess the association between cancer and cardiovascular (CV) outcomes. Among 9749 patients, 23.8% had history of cancer (57% solid malignancy, 1.3% leukaemia, 3.3% lymphoma, 40% other type, and 2.2% metastatic cancer). Patients with history of cancer were older, more likely to have CV disease, CV risk factors, and prior gastrointestinal bleeding. No difference in antiarrhythmic and antithrombotic therapy was observed between those with and without cancer. Patients with history of cancer had a significantly higher risk of death (7.8 vs. 4.9 deaths per 100 patient-years follow-up, P = 0.0003) mainly driven by non-CV death (4.2 vs. 2.4 per 100 patient-years follow-up; P = 0.0004) and higher risk of major bleeding (5.1 vs. 3.5 per 100 patient-years follow-up; P = 0.02) compared with non-cancer patients; no differences were observed in risks of strokes/non-central nervous system embolism (1.96 vs. 1.48, P = 0.74) and CV death (2.89 vs. 2.07, P = 0.35) between the two groups. Conclusion A history of cancer is common among AF patients with up to one in four patients having both. Antithrombotic therapy, rates of cerebrovascular accident, other thrombotic events and cardiac death were similar in AF patients with or without a history of cancer. Patients with cancer, however, were at higher risk of major bleeding and non-CV death.

Background— Temporary interruption of oral anticoagulation for procedures is often required, and some propose using bridging anticoagulation. However, the use and outcomes of bridging during oral anticoagulation interruptions in clinical practice are unknown. Methods and Results— The Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry is a prospective, observational registry study of US outpatients with atrial fibrillation. We recorded incident temporary interruptions of oral anticoagulation for a procedure, including the use and type of bridging therapy. Outcomes included multivariable-adjusted rates of myocardial infarction, stroke or systemic embolism, major bleeding, cause-specific hospitalization, and death within 30 days. Of 7372 patients treated with oral anticoagulation, 2803 overall interruption events occurred in 2200 patients (30%) at a median follow-up of 2 years. Bridging anticoagulants were used in 24% (n=665), predominantly low-molecular-weight heparin (73%, n=487) and unfractionated heparin (15%, n=97). Bridged patients were more likely to have had prior cerebrovascular events (22% versus 15%; P =0.0003) and mechanical valve replacements (9.6% versus 2.4%; P <0.0001); however, there was no difference in CHA 2 DS 2 -VASc scores (scores ≥2 in 94% versus 95%; P =0.5). Bleeding events were more common in bridged than nonbridged patients (5.0% versus 1.3%; adjusted odds ratio, 3.84; P <0.0001). The incidence of myocardial infarction, stroke or systemic embolism, major bleeding, hospitalization, or death within 30 days was also significantly higher in patients receiving bridging (13% versus 6.3%; adjusted odds ratio, 1.94; P =0.0001). Conclusions— Bridging anticoagulation is used in one quarter of anticoagulation interruptions and is associated with higher risk for bleeding and adverse events. These data do not support the use of routine bridging, and additional data are needed to identify best practices concerning anticoagulation interruptions. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01165710.

Background Dabigatran is a novel oral anticoagulant approved for thromboprophylaxis in atrial fibrillation. Adoption patterns of this new agent in community practice are unknown. Methods and Results We studied patterns of dabigatran use among patients enrolled in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT‐AF) Registry between June 2010 and August 2011 and followed for 12 months. Among 9974 atrial fibrillation patients included, 1217 (12%) were treated with dabigatran during the study. Overall, patients receiving dabigatran were younger (median age 72 versus 75 years, P <0.0001), more likely to be white (92% versus 89%, P =0.005), more likely to have private insurance (33% versus 25%, P <0.0001), and less likely to have prior cardiovascular disease (4% versus 33%, P <0.0001). They had more new‐onset atrial fibrillation (8.8% versus 4.1%, P <0.0001), lower CHADS 2 scores (estimated risk based on the presence of congestive heart failure, hypertension, aged ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack; mean 2.0 versus 2.3, P <0.0001), and lower Anticoagulation and Risk Factors in Atrial Fibrillation scores (mean 2.4 versus 2.8, P <0.0001). More than half (n=14/25, 56%) of patients with severe kidney disease were not prescribed reduced dosing, whereas 10% (n=91/920) with preserved renal function received lower dosing. Among patients not on dabigatran at baseline, 8% had dabigatran initiated during follow‐up. Patient education was significantly associated with switching from warfarin to dabigatran (adjusted odds ratio for postgraduate 1.73, P =0.007), whereas antiarrhythmic drug use significantly correlated with de novo adoption of dabigatran (adjusted odds ratio 2.4, P <0.0001). Conclusions Patients receiving dabigatran were younger and at a lower risk of stroke and bleeding. Patients appeared to drive switching from warfarin, whereas clinical characteristics influenced de novo start of dabigatran. These data suggest cautious early uptake of dabigatran, and more careful attention to dosing adjustments is warranted. Clinical Trial Registration URL : Clinicaltrials.gov. Unique identifier: NCT 01165710.

Background— Patients with atrial fibrillation (AF) at the highest stroke risk derive the largest benefit from oral anticoagulation (OAC). Those with the highest stroke risk have been paradoxically less likely to receive OAC. This study assessed the association between stroke and bleeding risk on rates of OAC. Methods and Results— We analyzed OAC use among 10 098 patients with AF from 174 community-based outpatient practices enrolled in 2010–2011 in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). OAC was defined as warfarin or dabigatran use at study enrollment. Stroke and bleeding risk were calculated using congestive heart failure, hypertension, age, diabetes mellitus, prior stroke (CHADS 2 ), and anticoagulation and risk factors in AF (ATRIA) scores, respectively. The mean subject age was 73 years; 58% were men. Overall, 76% of patients received OAC (71% warfarin and 5% dabigatran). The use of OAC increased among those with higher CHADS 2 scores, from 53% for CHADS 2 =0 to 80% for CHADS 2 ≥2 ( P <0.001). OAC use fell slightly with increasing ATRIA bleeding risk score, from 81% for ATRIA=3 to 73% for ATRIA≥5 ( P <0.001). A significant interaction existed between ATRIA and CHADS 2 scores ( P =0.021). Among those with low bleeding risk, use of OAC increased significantly with increasing stroke risk. Among those with high bleeding risk, CHADS 2 stroke risk had a smaller impact on use of OAC. Conclusions— In community-based outpatients with AF, use of OAC was high and driven by not only predominantly stroke but also bleeding risk. Stroke risk significantly affects OAC use among those with low bleeding risk, whereas those with high bleeding risk demonstrate consistently lower use of OAC regardless of stroke risk.