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This study sought to evaluate inappropriate prescribing practices in an atrial fibrillation (AF) population, as outlined by the 2016 ACC/AHA Clinical Performance and Quality Measures for Adults with Atrial Fibrillation or Atrial Flutter document. The 2016 AF quality measures document specified medications to avoid in certain AF populations, including aspirin and anticoagulant combination therapy in patients without cardiovascular disease, and non-dihydropyridine calcium channel blockers in patients with reduced ejection fraction. Using data from the NCDR PINNACLE registry, a national outpatient cardiology practice registry, we assessed rates of inappropriate prescription of two types of medications among AF outpatients from 5/1/2008-5/1/2016. Overall rates of inappropriate prescription and variation by practice were calculated. Patient and practice factors associated with inappropriate prescription were assessed in adjusted analyses. A total of 107,759 of 658,250 (16.4%) patients without cardiovascular disease were inappropriately prescribed an antiplatelet and anticoagulant together, and 5,731 of 150,079 (3.8%) patients with reduced ejection fraction were inappropriately prescribed a non-dihydropyridine calcium channel blocker. Overall, 14.8% of AF patients were prescribed medications that were not recommended. Both patient and practice factors were associated with inappropriate prescribing, and the adjusted practice-level median odds ratio for inappropriate prescription was 1.70 (95% CI: 1.61-1.82), indicating a 70% likelihood that 2 random practices would treat identical AF patients differently. In a large registry of AF patients treated in cardiology practices, overall rates of inappropriate prescription practices, as defined by the 2016 AF quality measures, were relatively low, but significant practice variation was present., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Previous studies examining the use of direct oral anticoagulants (DOACs) in atrial fibrillation (AF) have largely focused on patients newly initiating therapy. Little is known about the prevalence/patterns of switching to DOACs among AF patients initially treated with warfarin., Hypothesis: To examine patterns of anticoagulation among patients chronically managed with warfarin upon the availability of DOACs and identify patient/practice-level factors associated with switching from chronic warfarin therapy to a DOAC., Methods: Prospective cohort study of AF patients in the NCDR PINNACLE registry prescribed warfarin between May 1, 2008 and May 1, 2015. Patients were followed at least 1 year (median length of follow-up 375 days, IQR 154-375) through May 1, 2016 and stratified as follows: continued warfarin, switched to DOAC, or discontinued anticoagulation. To identify significant predictors of switching, a three-level multivariable hierarchical regression was developed., Results: Among 383 008 AF patients initially prescribed warfarin, 16.3% (n = 62 620) switched to DOACs, 68.8% (n = 263 609) continued warfarin, and 14.8% (n = 56 779) discontinued anticoagulation. Among those switched, 37.6% received dabigatran, 37.0% rivaroxaban, 24.4% apixaban, and 1.0% edoxaban. Switched patients were more likely to be younger, women, white, and have private insurance (all P < .001). Switching was less likely with increased stroke risk (OR, 0.92; 95%CI, 0.91-0.93 per 1-point increase CHA 2 DS 2 -VASc), but more likely with increased bleeding risk (OR, 1.12; 95%CI, 1.10-1.13 per 1-point increase HAS-BLED). There was substantial variation at the practice-level (MOR, 2.33; 95%CI, 2.12-2.58) and among providers within the same practice (MOR, 1.46; 95%CI, 1.43-1.49)., Conclusions: Among AF patients treated with warfarin between October 1, 2010 and May 1, 2016, one in six were switched to DOACs, with differences across sociodemographic/clinical characteristics and substantial practice-level variation. In the context of current guidelines which favor DOACs over warfarin, these findings help benchmark performance and identify areas of improvement., (© 2020 The Authors. Clinical Cardiology published by Wiley Periodicals, Inc.)

Direct oral anticoagulants (DOACs) have a favorable bleeding risk profile in patients with atrial fibrillation (AF). However, the safety of individual DOACs relative to warfarin for specific bleeding outcomes is less certain. We identified 423,450 patients with AF between 2013 to 2015 in the NCDR PINNACLE national ambulatory registry matched to the Centers for Medicare and Medicaid Services database. Outcomes included time to first major bleed, intracranial hemorrhage (ICH), major gastrointestinal bleed (GIB), or other major bleed. We estimated the association of OAC with bleeding using Cox proportional hazard models. The median duration of follow-up was 1.4 years. OACs were used in 64% of AF patients (66% warfarin, 15% rivaroxaban, 12% dabigatran, and 7% apixaban). A major bleeding event occurred in 6.9% of patients. Compared with warfarin users, fewer patients experienced ICH with the use of rivaroxaban (HR 0.73; 95% CI 0.64 to 0.84), dabigatran (HR 0.56; 95% CI 0.48 to 0.65), and apixaban (HR 0.70; 95% CI 0.55 to 0.90). The risk of major GIB was higher in rivaroxaban users (HR 1.20; 95% CI 1.12 to 1.27), and lower in dabigatran (HR 0.88; 95% CI 0.82 to 0.95) and apixaban (HR 0.84; 95% CI 0.74 to 0.95) users. For any DOAC versus warfarin, age (≥75 or <75 years) interacted with major bleeding (HR 0.93 vs 0.78; p <0.001), GIB (HR 1.10 vs 0.82; p <0.001), and other major bleeding (HR 0.93 vs 0.80; p <0.001). In conclusion, our results suggest that the safety of DOACs is superior to warfarin in AF patients, except with rivaroxaban and GIB. Age ≥75 years attenuated the relative safety benefits of DOACs., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: In non-valvular atrial fibrillation (NVAF) patients, congestive heart failure (CHF) confers an increased risk of stroke or systemic thromboembolism. This risk is present in both heart failure (HF) with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). It is unclear if clinicians account for both types of CHF in their NVAF anticoagulation practices. Accordingly, we characterized current outpatient anticoagulation trends in NVAF patients with HFpEF compared to patients with HFrEF., Methods: The outpatient NCDR PINNACLE-AF registry was analyzed to identify patients with NVAF and CHF. The study population was subdivided into HFpEF (ie, LVEF ≥ 40%) and HFrEF (LVEF < 40%). Anticoagulation rates by CHF group were compared and stratified by CHA 2 DS 2 -VASc score., Results: A total of 340 127 patients with NVAF and CHF were identified, of whom 248 136 (73.0%) were classified as HFpEF and 91 991 (27.0%) as HFrEF. Patients with HFpEF had higher mean CHA 2 DS 2 -VASc scores and were more likely to be female, older, and have hypertension (P < 0.001). Unadjusted anticoagulation rates were significantly lower in patients with HFpEF compared to those with HFrEF (60.6% vs 64.2%, respectively). Lower rates of anticoagulation in the HFpEF group persisted after risk adjustment (RR: 0.93 [95% CI: 0.91, 0.94]). Stratification by CHA 2 DS 2 -VASc score demonstrated that lower rates of anticoagulation in patients with HFpEF persisted until a score of ≥5., Conclusions: Patients with NVAF and HFpEF have significantly lower anticoagulation rates when compared to their HFrEF counterparts. These findings suggest a potential underappreciation of HFpEF as a risk factor in patients with NVAF., (© 2018 The Authors. Clinical Cardiology Published by Wiley Periodicals, Inc.)

Background: Many patients with atrial fibrillation (AF) and elevated stroke risk are not prescribed oral anticoagulation (OAC) despite evidence of benefit. Identification of factors associated with OAC non-prescription could lead to improvements in care., Methods and Results: Using NCDR PINNACLE, a United States-based ambulatory cardiology registry, we examined factors associated with OAC non-prescription in patients with non-valvular AF at elevated stroke risk (CHA 2 DS 2 -VASc ≥2) between January 5, 2008 and December 31, 2014. Among 674,841 patients, 57% were treated with OAC (67% of whom were treated with warfarin). OAC prescription varied widely (28%-75%) across preselected strata of age, stroke risk (CHA 2 DS 2 -VASc), and bleeding risk (HAS-BLED), generally indicating that older patients at high stroke and low bleeding risk are commonly treated with OAC. Other factors associated with OAC non-prescription included reversible AF etiology; female sex; liver, renal, or vascular disease; and physician versus non-physician provider. Antiplatelet use was common (57%) and associated with the greatest risk of OAC non-prescription (odds ratio [OR] 4.44, 95% confidence interval [CI] 4.39-4.49)., Conclusions: In this registry of AF patients, older patients at elevated stroke and low bleeding risk were commonly treated with OAC. However, a variety of factors were associated with OAC non-prescription. Specifically, antiplatelet use was prevalent and associated with the highest likelihood of OAC non-prescription. Future studies are warranted to understand provider and patient rationale that may underlie observed associations with OAC non-prescription., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: It is poorly understood whether insurance type may be a major contributor to the underuse of oral anticoagulation (OAC) among patients with atrial fibrillation (AF), particularly for novel oral anticoagulants (NOACs)., Methods: We performed a retrospective cohort registry study of patients with insurance, AF, CHA 2 DS 2 -VASc ≥2, and at least one outpatient encounter recorded in the ACC NCDR's PINNACLE Registry between January 1, 2011 and December 31, 2014. We used hierarchical regression, adjusting for patient characteristics and clustering by physician, to evaluate the association of insurance type (Private, Military, Medicare, Medicaid, Other) with receipt of OAC (any OAC, warfarin, or NOAC)., Results: In 363,309 patients (age 75±10; 48% female), we found a significant difference in proportions of OAC and NOAC prescription across insurance types (OAC: Military 53%, Private 53%, Medicare 52%, Other 41%, Medicaid 41%, P<.001; NOAC: Military 24%, Private 19%, Medicare 17%, Other 17%, Medicaid 8%, P<.001). After adjustment for patient characteristics and facility, private, Medicaid, and other insurance were independently associated with a lower odds of OAC prescription relative to Medicare, but military insured patients were not significantly different. After adjustment, military and private insurance were independently associated with a higher odds of NOAC prescription relative to Medicare, while Medicaid and other insurance were associated with a lower odds of NOAC prescription., Conclusions: In a contemporary US AF population, there was significant variation of OAC prescription across insurance plans, with the highest among private and Medicare insured patients. These differences may indicate that insurance plan, and its associated pharmacy benefits, affect the pace of diffusion of new therapies., (Copyright © 2017. Published by Elsevier Inc.)

Background: The direct oral anticoagulants (DOACs) reduce the risk of stroke in moderate to high-risk patients with non-valvular atrial fibrillation (AF). Yet, concerns remain regarding its routine use in real world practice. We sought to describe adherence patterns and the association between adherence and outcomes to the DOACs among outpatients with AF., Methods: We performed a retrospective cohort study of patients in the VA Healthcare System who initiated pharmacotherapy with dabigatran, rivaroxaban, or apixaban between November 2010 and January 2015 for non-valvular AF with CHA 2 DS 2 -VASc score ≥ 2. Adherence was determined using pharmacy refill data and estimated by the proportion of days covered (PDC) over the first year of therapy. Clinical outcomes, including all-cause mortality and stroke, were measured at 6 months and used to assess measures of adherence for each DOAC., Results: A total of 2882 patients were included. Most were prescribed dabigatran (72.7%), compared with rivaroxaban (19.8%) or apixaban (7.5%). The mean PDC was 0.84 ± 0.20 for dabigatran, 0.86 ± 0.18 for rivaroxaban, and 0.89 ± 0.14 for apixaban (p < 0.01). The proportion of non-adherent patients, PDC <0.80, was 27.6% for all and varied according DOAC. Lower adherence to dabigatran was associated with higher risk of mortality and stroke (HR 1.07; 1.03-1.12 per 0.10 decline in PDC)., Conclusions: In a real-world VA population being prescribed anticoagulation for AF, more than one quarter had sub-optimal adherence. Lower adherence was associated with a higher risk of mortality and stroke. Efforts identifying non-adherent patients, and targeted adherence interventions are needed to improve outcomes.

Background: Atrial fibrillation (AF) and heart failure with reduced ejection fraction frequently coexist. The AATAC (Ablation versus Amiodarone for Treatment of persistent Atrial fibrillation in patients with Congestive heart failure and an implantable device) trial suggests that catheter ablation may benefit these patients. However, applicability to contemporary ambulatory cardiology practice is unknown., Methods and Results: Using the outpatient National Cardiovascular Data Registry ® Practice Innovation and Clinical Excellence Registry, we identified participants meeting AATAC enrollment criteria between 2013 and 2014. Treatment with medications and procedures was assessed at registry inclusion. From 164 166 patients with AF and heart failure, 8483 (7%) patients potentially met AATAC inclusion criteria. Eligible subjects, compared to AATAC trial participants, were older (mean age, 71.2±11.4 years) and had greater comorbidity (coronary artery disease 79.2%, hypertension 82.4%, and diabetes mellitus 31.8%). AF was predominantly paroxysmal (65.5%), rather than persistent/permanent (16.7%) or new onset (17.8%), whereas all patients in the AATAC trial had persistent AF. Commonly used atrioventricular-nodal blocking agents were carvedilol (71.2%), digoxin (31.9%), and metoprolol (27.1%). Rhythm control with anti-arrhythmic drugs was reported in 29.0% of AATAC eligible patients (predominantly amiodarone [24.6%]) and 9.3% had undergone catheter ablation. Patients who underwent ablation were more likely to be younger and have less comorbidities than those who did not., Conclusions: Among the contemporary ambulatory AF/heart failure with reduced ejection fraction population, treatment is predominantly rate control with few catheter ablations. Application of AATAC findings has the potential to markedly increase the use of catheter ablation in this population, although significant differences in clinical profiles might influence ablation outcomes in practice., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Despite higher thromboembolism risk, women with atrial fibrillation have lower oral anticoagulation (OAC) use compared to men. The influence of the CHA 2 DS 2 -VASc score or the introduction of non-vitamin K OACs on this relationship is not known., Methods and Results: Using the PINNACLE National Cardiovascular Data Registry from 2008 to 2014, we compared the association of sex with OAC use (warfarin or non-vitamin K OACs) overall and by CHA 2 DS 2 -VASc score and examined temporal trends in OAC use by sex. Multivariable regression models assessed the association between sex and OAC use in those with CHA 2 DS 2 -VASc scores ≥2. Temporal analyses assessed changes in OAC use by sex over time. Of the 691 906 atrial fibrillation patients, 48.5% were women. Women were significantly less likely than men to use any OAC overall (56.7% versus 61.3%; P <0.001) and at all levels of CHA 2 DS 2 -VASc score (adjusted risk ratio 9% to 33% lower, all P <0.001). Compared to other thromboembolic risk factors, female sex was associated with lower use of OAC (risk ratio 0.90, 95%CI 0.90-0.91). Over time, non-vitamin K OAC use increased at a slightly higher rate in women (56.2% increase per year, 95%CI 54.6% to 57.9%) compared to men (53.6% increase per year, 95%CI 52.0% to 55.2%), yet women remained less likely to receive any OAC at all time points ( P <0.001)., Conclusions: Among patients with atrial fibrillation, women were significantly less likely to receive OAC at all levels of the CHA 2 DS 2 -VASc score. Despite increasing non-vitamin K OAC use, women had persistently lower rates of OAC use compared to men over time., (© 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Oral anticoagulation (OAC) with warfarin is underused for atrial fibrillation (AF). The availability of direct oral anticoagulants (DOACs) may improve overall OAC rates in AF patients, but a large-scale evaluation of their effects has not been conducted., Objectives: This study assessed the effect of DOAC availability on overall OAC rates for nonvalvular AF., Methods: Between April 1, 2008 and September 30, 2014, we identified 655,000 patients with nonvalvular AF and a CHA 2 DS 2 -VASc score of >1 in the National Cardiovascular Data Registry PINNACLE registry. Temporal trends in overall OAC and individual warfarin and DOAC use were analyzed. Multivariable hierarchical logistic regression identified patient factors associated with OAC and DOAC use. Practice variation of OAC and DOAC use was also assessed., Results: Overall OAC rates increased from 52.4% to 60.7% among eligible AF patients (p for trend <0.01). Warfarin use decreased from 52.4% to 34.8% (p for trend <0.01), and DOAC use increased from 0% to 25.8% (p for trend <0.01). An increasing CHA 2 DS 2 -VASc score was associated with higher OAC use (odds ratio [OR]: 1.06; 95% confidence interval [CI]: 1.05 to 1.07), but with lower DOAC use (OR: 0.97; 95% CI: 0.96 to 0.98). Significant practice variation was present in OAC use (median odds ratio [MOR]: 1.52; 95% CI: 1.45 to 1.57) and in DOAC use (MOR: 3.58; 95% CI: 3.05 to 4.13)., Conclusions: Introduction of DOACs in routine practice was associated with improved rates of overall OAC use for AF, but significant gaps remain. In addition, there is significant practice-level variation in OAC and DOAC use., (Copyright © 2017 American College of Cardiology Foundation. All rights reserved.)

Background: Decisions to use rhythm control in atrial fibrillation (AF) should generally be dictated by patient factors, such as quality of life, heart failure, and other comorbidities. Whether or not other factors affect decisions about the use of rhythm control, and catheter ablation in particular, is unknown., Methods: A cohort of all patients diagnosed with nonvalvular AF were identified from the National Cardiovascular Data Registry's Practice Innovation and Clinical Excellence (PINNACLE) AF registry of US outpatient cardiology practices during the study period from May 1, 2008, to December 31, 2014. Overall and practice-specific rates of rhythm control (cardioversion, antiarrhythmic drug therapy, or catheter ablation) were assessed. We assessed patient and practice factors associated with rhythm control and determined the relative contribution of patient, practice, and unmeasured practice factors with its use., Results: Among 511,958 PINNACLE AF patients, 22.3% were treated with rhythm control and 2.9% underwent catheter ablation. Significant practice variation in rhythm control was present (median rate of rhythm control across practices 22.8%, range 0.2%-62.9%). Significant patient factors associated with rhythm control therapy included white (vs nonwhite) race (odds ratio [OR] 2.43, P<.001), private (vs nonprivate) insurance (OR 1.04, P<.001), and whether a patient was seen by an electrophysiologist (OR 1.77, P<.001). In an analysis of the relative contribution of patient, practice, and unmeasured practice factors with rhythm control, the contribution of unmeasured practice factors (95% range OR 0.29-3.44) exceeded that of either patient (95% range OR 0.46-2.30) or practice (95% range OR 0.15-2.77) factors., Conclusions: One in 5 AF patients in the PINNACLE registry received rhythm control, and 1 in 50 received catheter ablation, suggesting that rhythm control may be underused. A variety of measured and unmeasured practice factors unrelated to patient characteristics play a disproportionate role in the use of rhythm control treatment decisions. Understanding the drivers of these decisions may identify inappropriate treatment variation and better inform optimal use of these therapies., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Use of the CHA 2 DS 2 -VASc score instead of the CHADS 2 score for thromboembolic risk stratification and initiation of oral anticoagulation (OAC) was recommended in the 2014 American Heart Association/American College of Cardiology/Heart Rhythm Society atrial fibrillation (AF) guidelines. We sought to define the proportion of patients with AF qualifying for and receiving OAC in contemporary practice by applying the CHA 2 DS 2 -VASc score to patients with a low CHADS 2 score., Methods and Results: Among patients with AF enrolled in the American College of Cardiology National Cardiovascular Data Registry's outpatient Practice Innovation and Clinical Excellence registry (2008-2014) CHADS 2 score of 0 or 1, we calculated the impact of adoption of the CHA 2 DS 2 -VASc score on the proportion of patients with an indication for OAC. We examined trends in prescription of OAC overall, direct OAC (dabigatran/rivaroxaban/apixaban), and multivariable associations between clinical characteristics and OAC use. Of 346 068 patients with AF aged 65±12 years, 61% were men and 65% were white. In total, 24% of those with CHADS 2 =0 and 81% of those with a CHADS 2 =1 were reclassified as having a definite indication for OAC (CHA 2 DS 2 -VASc score ≥2). OAC use increased from 37% to 48% during the study period, and direct OAC use increased from 5% to 30%. Increasing CHA 2 DS 2 -VASc score (odds ratio, 2.07; 95% confidence interval, 1.97-2.19 for score of 4 versus 0) and rhythm control strategy (odds ratio, 1.34; 95% confidence interval, 1.30-1.39) were associated with increased OAC use., Conclusions: Adoption of the CHA 2 DS 2 -VASc score reclassifies 64.5% of patients with AF with low CHADS 2 scores into a class I indication for OAC prescription. Overall OAC prescription increased between 2011 and 2014., (© 2017 American Heart Association, Inc.)

The Long-term Effect of Goal Directed Weight Management in an Atrial Fibrillation Cohort: A Long-term Follow-up Study (LEGACY) demonstrated that weight reduction in a cohort of Australian patients with atrial fibrillation (AF) resulted in a reduction in AF burden and improvement in AF symptom severity. The applicability of LEGACY in US cardiovascular practice is not known. A cohort of patients with AF from the National Cardiovascular Data Registry Practice Innovation and Clinical Excellence (PINNACLE) registry of US cardiovascular ambulatory care practices was created. The proportion of PINNACLE AF patients meeting enrollment criteria for LEGACY was assessed. Differences between these patients and LEGACY trial patients were qualitatively compared. Treatment for AF among LEGACY eligible and noneligible patients was compared. Among 349,999 US patients with AF from 179 cardiovascular practices in the PINNACLE registry, 197,255 (56.4%) met enrollment criteria for LEGACY. LEGACY-eligible PINNACLE AF had significantly lower rates of tobacco and alcohol abuse than the LEGACY trial population. There were significant differences in drug therapy comparing LEGACY eligible and LEGACY noneligible PINNACLE AF patients. In this cohort of patients in ambulatory practice in the United States with AF, over 1/2 were potential candidates for a weight management program. Differences between patients in practice and those enrolled in the trial could influence the success and impact of the LEGACY weight management intervention. Our study identifies a potential opportunity to improve AF morbidity and costs to the health care system in the United States by implementing a structured weight reduction program, such as that described in LEGACY., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Oral anticoagulation (OAC), rather than aspirin, is recommended in patients with atrial fibrillation (AF) at moderate to high risk of stroke., Objectives: This study sought to examine patient and practice-level factors associated with prescription of aspirin alone compared with OAC in AF patients at intermediate to high stroke risk in real-world cardiology practices., Methods: The authors identified 2 cohorts of outpatients with AF and intermediate to high thromboembolic risk (CHADS2 score ≥2 and CHA2DS2-VASc ≥2) enrolled in the American College of Cardiology PINNACLE (Practice Innovation and Clinical Excellence) registry between 2008 and 2012. Using hierarchical modified Poisson regression models adjusted for patient and practice characteristics, the authors examined the prevalence and predictors of aspirin alone versus OAC prescription in AF patients at risk for stroke., Results: Of 210,380 identified patients with CHADS2 score ≥2 on antithrombotic therapy, 80,371 (38.2%) were treated with aspirin alone, and 130,009 (61.8%) were treated with warfarin or non-vitamin K antagonist OACs. In the cohort of 294,642 patients with CHA2DS2-VASc ≥2, 118,398 (40.2%) were treated with aspirin alone, and 176,244 (59.8%) were treated with warfarin or non-vitamin K antagonist OACs. After multivariable adjustment, hypertension, dyslipidemia, coronary artery disease, prior myocardial infarction, unstable and stable angina, recent coronary artery bypass graft, and peripheral arterial disease were associated with prescription of aspirin only, whereas male sex, higher body mass index, prior stroke/transient ischemic attack, prior systemic embolism, and congestive heart failure were associated with more frequent prescription of OAC., Conclusions: In a large, real-world cardiac outpatient population of AF patients with a moderate to high risk of stroke, more than 1 in 3 were treated with aspirin alone without OAC. Specific patient characteristics predicted prescription of aspirin therapy over OAC., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Importance: Patients with atrial fibrillation (AF) are at a proportionally higher risk of stroke based on accumulation of well-defined risk factors., Objective: To examine the extent to which prescription of an oral anticoagulant (OAC) in US cardiology practices increases as the number of stroke risk factors increases., Design, Setting, and Participants: Cross-sectional registry study of outpatients with AF enrolled in the American College of Cardiology National Cardiovascular Data Registry's PINNACLE (Practice Innovation and Clinical Excellence) Registry between January 1, 2008, and December 30, 2012. As a measure of stroke risk, we calculated the CHADS2 score and the CHA2DS2-VASc score for all patients. Using multinomial logistic regression models adjusted for patient, physician, and practice characteristics, we examined the association between increased stroke risk score and prescription of an OAC., Main Outcomes and Measures: The primary outcome was prescription of an OAC with warfarin sodium or a non-vitamin K antagonist OAC., Results: The study cohort comprised 429 417 outpatients with AF. Their mean (SD) age was 71.3 (12.9) years, and 55.8% were male. Prescribed treatment consisted of an OAC (192 600 [44.9%]), aspirin only (111 134 [25.9%]), aspirin plus a thienopyridine (23 454 [5.5%]), or no antithrombotic therapy (102 229 [23.8%]). Each 1-point increase in risk score was associated with increased odds of OAC prescription compared with aspirin-only prescription using the CHADS2 score (adjusted odds ratio, 1.158; 95% CI, 1.144-1.172; P < .001) and the CHA2DS2-VASc score (adjusted odds ratio, 1.163; 95% CI, 1.157-1.169; P < .001). Overall, OAC prescription prevalence did not exceed 50% even in higher-risk patients with a CHADS2 score exceeding 3 or a CHA2DS2-VASc score exceeding 4., Conclusions and Relevance: In a large quality improvement registry of outpatients with AF, prescription of OAC therapy increased with a higher CHADS2 score and CHA2DS2-VASc score. However, a plateau of OAC prescription was observed, with less than half of high-risk patients receiving an OAC prescription.

Background: There is a reported association between high clinical volume and improved outcomes. Whether this relationship is true for outpatients with coronary artery disease (CAD), heart failure (HF), and atrial fibrillation (AF) remains unknown., Methods and Results: Using the PINNACLE Registry (2009-2012), average monthly provider and practice volumes were calculated for CAD, HF, and AF. Adherence with 4 American Heart Association CAD, 2 HF, and 1 AF performance measure were assessed at the most recent encounter for each patient. Hierarchical logistic regression models were used to assess the relationship between provider and practice volume and performance on eligible quality measures. Data incorporated patients from 1094 providers at 71 practices (practice level analyses n=654 535; provider level analyses n=529 938). Median monthly provider volumes were 79 (interquartile range [IQR], 51-117) for CAD, 27 (16-45) for HF, and 37 (24-54) for AF. Median monthly practice volumes were 923 (IQR, 476-1455) for CAD, 311 (145-657) for HF, and 459 (185-720) for AF. Overall, 55% of patients met all CAD measures, 72% met all HF measures, and 58% met the AF measure. There was no definite relationship between practice volume and concordance for CAD, AF, or HF (P=0.56, 0.52, and 0.79, respectively). In contrast, higher provider volume was associated with increased concordance for CAD and AF performance measures (P<0.001 for both), but not for HF (P=0.36)., Conclusions: In the PINNACLE registry, performance was modest and variable. Higher provider volume was positively associated with quality, whereas practice volume was not., (© 2015 American Heart Association, Inc.)

Atrial fibrillation (AF) is a very common arrhythmia and significantly increases stroke risk. This risk can be mitigated with oral anticoagulation, but AF is often asymptomatic, or occult, preventing timely detection and treatment. Accordingly, occult AF may cause stroke before it is clinically diagnosed. Currently, guidelines for the early detection and treatment of occult AF are limited. This review addresses recent advancements in occult AF detection methods, identification of populations at high risk for occult AF, the treatment of occult AF with oral anticoagulation, as well as ongoing trials that may answer critically important questions regarding occult AF screening., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Patients with paroxysmal and persistent atrial fibrillation experience a similar risk of thromboembolism. Therefore, consensus guidelines recommend anticoagulant therapy in those at risk for thromboembolism irrespective of atrial fibrillation classification. We sought to examine whether there are differences in rates of appropriate oral anticoagulant treatment among patients with paroxysmal vs persistent atrial fibrillation in real-world cardiology practices., Methods: We studied 71,316 outpatients with atrial fibrillation and intermediate to high thromboembolic risk (CHADS2 score ≥2) enrolled in the American College of Cardiology PINNACLE Registry between 2008 and 2012. Using hierarchical modified Poisson regression models adjusted for patient characteristics, we examined whether anticoagulant treatment rates differed between patients with paroxysmal vs persistent atrial fibrillation., Results: The majority of outpatients (78.4%, n = 55,905) had paroxysmal atrial fibrillation. In both unadjusted and multivariable adjusted analyses, patients with paroxysmal atrial fibrillation were less frequently prescribed oral anticoagulant therapy than those with persistent atrial fibrillation (50.3% vs 64.2%; adjusted risk ratio [RR] 0.74; 95% confidence interval [CI], 0.72-0.76). Instead, patients with paroxysmal atrial fibrillation were prescribed more frequently only antiplatelet therapy (35.1% vs 25.0%; adjusted RR 1.77; 95% CI, 1.69-1.86) or neither antiplatelet nor anticoagulant therapy (14.6% vs 10.8%; adjusted RR 1.35; 95% CI, 1.26-1.44; P < .0001 for differences across all 3 comparisons)., Conclusions: In a large, real-world cardiac outpatient population, patients with paroxysmal atrial fibrillation with a moderate to high risk of stroke were less likely to be prescribed appropriate oral anticoagulant therapy and more likely to be prescribed less effective or no therapy for thromboembolism prevention., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Warfarin is a complex but highly effective treatment for decreasing thromboembolic risk in atrial fibrillation (AF). We examined contemporary warfarin treatment rates in AF before the expected introduction of newer anticoagulants and extent of practice-level variation in warfarin use. Within the National Cardiovascular Data Registry Practice Innovation and Clinical Excellence program from July 2008 through December 2009, we identified 9,113 outpatients with AF from 20 sites who were at moderate to high risk for stroke (congestive heart failure, hypertension, age, diabetes, stroke score >1) and would be optimally treated with warfarin. Using hierarchical models, the extent of site-level variation was quantified with the median rate ratio, which can be interpreted as the likelihood that 2 random practices would differ in treating "identical" patients with warfarin. Overall rate of warfarin treatment was only 55.1% (5,018 of 9,913). Untreated patients and treated patients had mean congestive heart failure, hypertension, age, diabetes, stroke scores of 2.5 (p = 0.38) and similar rates of heart failure, hypertension, diabetes mellitus, and previous stroke, suggesting an almost "random" pattern of treatment. At the practice level, however, there was substantial variation in treatment ranging from 25% to 80% (interquartile range for practices 50 to 65), with a median rate ratio of 1.31 (1.22 to 1.55, p <0.001). In conclusion, within the Practice Innovation and Clinical Excellence registry, we found that warfarin treatment in AF was suboptimal, with large variations in treatment observed across practices. Our findings suggest important opportunities for practice-level improvement in stroke prevention for outpatients with AF and define a benchmark treatment rate before the introduction of newer anticoagulant agents., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Autonomic dysfunction appears to play a significant role in the development of atrial fibrillation (AF), and impaired heart rate recovery (HRR) during exercise treadmill testing (ETT) is a known marker for autonomic dysfunction. However, whether impaired HRR is associated with incident AF is unknown. We studied the association of impaired HRR with the development of incident AF, after controlling for demographic and clinical confounders., Methods: We studied 8236 patients referred for ETT between 2001 and 2004, and without a prior history of AF. Patients were categorized by normal or impaired HRR on ETT. The primary outcome was the development of AF. Cox proportional hazards modeling was used to control for demographic and clinical characteristics. Secondary analyses exploring a continuous relationship between impaired HRR and AF, and exploring interactions between cardiac medication use, HRR, and AF were also conducted., Results: After adjustment, patients with impaired HRR were more likely to develop AF than patients with normal HRR (HR 1.43, 95% confidence interval (CI) 1.06, 1.93). In addition, there was a linear trend between impaired HRR and AF (HR 1.05 for each decreasing BPM in HRR, 95% CI 0.99, 1.11). No interactions between cardiac medications, HRR, and AF were noted., Conclusion: Patients with impaired HRR on ETT were more likely to develop new-onset AF, as compared to patients with normal HRR. These findings support the hypothesis that autonomic dysfunction mediates the development of AF, and suggest that interventions known to improve HRR, such as exercise training, may delay or prevent AF.

Background: Use of the CHA2DS2-VASc score instead of the CHADS2 score for thromboembolic risk stratification and initiation of oral anticoagulation (OAC) was recommended in the 2014 American Heart Association/American College of Cardiology/Heart Rhythm Society atrial fibrillation (AF) guidelines. We sought to define the proportion of patients with AF qualifying for and receiving OAC in contemporary practice by applying the CHA2DS2-VASc score to patients with a low CHADS2 score.Methods and Results: Among patients with AF enrolled in the American College of Cardiology National Cardiovascular Data Registry's outpatient Practice Innovation and Clinical Excellence registry (2008-2014) CHADS2 score of 0 or 1, we calculated the impact of adoption of the CHA2DS2-VASc score on the proportion of patients with an indication for OAC. We examined trends in prescription of OAC overall, direct OAC (dabigatran/rivaroxaban/apixaban), and multivariable associations between clinical characteristics and OAC use. Of 346 068 patients with AF aged 65±12 years, 61% were men and 65% were white. In total, 24% of those with CHADS2=0 and 81% of those with a CHADS2=1 were reclassified as having a definite indication for OAC (CHA2DS2-VASc score ≥2). OAC use increased from 37% to 48% during the study period, and direct OAC use increased from 5% to 30%. Increasing CHA2DS2-VASc score (odds ratio, 2.07; 95% confidence interval, 1.97-2.19 for score of 4 versus 0) and rhythm control strategy (odds ratio, 1.34; 95% confidence interval, 1.30-1.39) were associated with increased OAC use.Conclusions: Adoption of the CHA2DS2-VASc score reclassifies 64.5% of patients with AF with low CHADS2 scores into a class I indication for OAC prescription. Overall OAC prescription increased between 2011 and 2014. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies have examined patterns of DOACs in AF, but have exclusively focused on patients newly initiating therapy, and neglect the large reservoir of patients who were chronically receiving warfarin. We sought to examine predictors and patterns of care for patients switched from warfarin to DOACs. Methods: The study cohort included all patients in the NCDR PINNACLE registry with at least one prescription for warfarin for AF between May 1, 2008 and May 1, 2015. Patients were followed longitudinally and stratified based on their anticoagulation between October 1, 2010 and May 1, 2016 as follows: 1) continued warfarin, 2) switched to a DOAC, or 3) discontinued anticoagulation. To identify significant predictors of switching, a three level multivariable hierarchical regression was conducted, with patient baseline characteristics, comorbidities and medication use included as fixed effects, and practices and providers within the same practice modeled as random effects. Results: Of the 383,008 patients included, 62,620 (16.3%) switched to a DOAC while 263,609 (68.8%) continued on warfarin. Patients switching from warfarin to a DOAC were younger, white, have private insurance, and history of prior stroke; while those who were not switched tended to have diabetes, coronary artery disease, and heart failure (p<0.001 for all, Figure). The mean (SD) CHADS2-VASC for those switched was 3.5±1.7 and for those not switched 3.7±1.6; the mean (SD) HAS-BLED for those switched was 2.2±1.0 and for those not switched 2.2±0.9. There was substantial variation in switching patterns with a median odds ratio at the practice level of 2.42 (95% CI, 2.20-2.68) and for providers within the same practice 1.47 (95% CI, 1.44-1.50). Conclusions: There is substantial variation in patterns of switching from warfarin to DOACs with significant disparities based on sociodemographic characteristics without differences based on bleeding risk. [ABSTRACT FROM AUTHOR]

Background: Multilevel models for non-normal outcomes are widely used in medical and health sciences research. While methods for interpreting fixed effects are well-developed, methods to quantify and interpret random cluster variation and compare it with other sources of variation are less established. Random cluster variation, sometimes referred to as general contextual effects (GCE), may be the main focus of a study; therefore, easily interpretable methods are needed to quantify GCE. We propose a Reference Effect Measure (REM) approach to 1) quantify GCE and compare it to individual subject and cluster covariate effects, and 2) quantify relative magnitudes of GCE and variation from sets of measured factors.Methods: To illustrate REM, we consider a two-level mixed logistic model with patients clustered within hospitals and a random intercept for hospitals. We compare patients at hospitals at given percentiles of the estimated random effect distribution to patients at a median or 'reference' hospital. These estimates are then compared numerically and graphically to individual fixed effects to quantify GCE in the context of effects of other measured variables (aim 1). We then extend this approach by comparing variation from the random effect distribution to variation from sets of fixed effects to understand their magnitudes relative to overall outcome variation (aim 2).Results: Using an example of initiation of rhythm control treatment in atrial fibrillation (AF) patients within the Veterans Affairs (VA), we use REM to demonstrate that random variation across hospitals (GCE) in initiation of treatment is substantially greater than that due to most individual patient factors, and explains at least as much variation in treatment initiation as do all patient factors combined. These results are contrasted with a relatively small GCE compared with patient factors in 1 year mortality following hospitalization for AF patients.Conclusions: REM provides a means of quantifying random effect variation (GCE) with multilevel data and can be used to explore drivers of outcome variation. This method is easily interpretable and can be presented visually. REM offers a simple, interpretable approach for evaluating questions of growing importance in the study of health care systems. [ABSTRACT FROM AUTHOR]