Search

Background: Randomized clinical trials have demonstrated that catheter ablation for atrial fibrillation in patients with heart failure with reduced ejection fraction may improve survival and other cardiovascular outcomes. Methods: We constructed a decision-analytic Markov model to estimate the costs and benefits of catheter ablation and medical management in patients with symptomatic heart failure with reduced ejection fraction (left ventricular ejection fraction ≤35%) and atrial fibrillation over a lifetime horizon. Evidence from the published literature informed the model inputs, including clinical effectiveness data from meta-analyses. Probabilistic and deterministic sensitivity analyses were performed. A 3% discount rate was applied to both future costs and benefits. The primary outcome was the incremental cost-effectiveness ratio assessed from the US health care sector perspective. Results: Catheter ablation was associated with 6.47 (95% CI, 5.89–6.93) quality-adjusted life years (QALYs) and a total cost of $105 657 (95% CI, $55 311–$191 934; 2018 US dollars), compared with 5.30 (95% CI, 5.20–5.39) QALYs and $63 040 (95% CI, $37 624–$102 260) for medical management. The incremental cost-effectiveness ratio for catheter ablation compared with medical management was $38 496 (95% CI, $5583–$117 510) per QALY gained. Model inputs with the greatest variation on incremental cost-effectiveness ratio estimates were the cost of ablation and the effect of catheter ablation on mortality reduction. When assuming a more conservative estimate of the treatment effect of catheter ablation on mortality (hazard ratio of 0.86), the estimated incremental cost-effectiveness ratio was $74 403 per QALY gained. At a willingness-to-pay threshold of $100 000 per QALY gained, atrial fibrillation ablation was found to be economically favorable compared with medical management in 95% of simulations. Conclusions: Catheter ablation in patients with heart failure with reduced ejection fraction patients and atrial fibrillation may be considered economically attractive at current benchmarks for societal willingness-to-pay in the United States.

Background: The Atrial Fibrillation Effect on Quality-of-Life (AFEQT) questionnaire has recently been validated to measure the impact of atrial fibrillation on quality of life, but a clinically important difference in AFEQT score has not been well defined. Methods and Results: To determine the clinically important difference in overall AFEQT (score range= 0 [worst] to 100 [best]) and selected subscales, we analyzed data in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry, a United States-based outpatient atrial fibrillation registry. AFEQT was assessed at baseline and 1 year in a subset of 1347 ORBIT-AF patients from 80 US sites participating in ORBIT-AF from June 2010 to August 2011. The mean change method was used to relate changes in 1-year AFEQT scores to clinically important changes in the physician assessment of European Heart Rhythm Association functional status (1 class improvement and separately 1 class deterioration). Clinically important differences and 95% CI corresponding to either a 1 European Heart Rhythm Association class improvement or deterioration were 5.4 (3.6–7.2) and −4.2 (−6.9 to −1.5) AFEQT points, respectively. Similarly, clinically important difference values were seen for a 1 European Heart Rhythm Association class improvement for the AFEQT subscales Activities of Daily Living and Symptoms: 5.1 (2.5–7.6) and 7.1 (5.3–9.0) AFEQT points, respectively. Conclusions: Based on the anchor of 1 European Heart Rhythm Association class change, changes in AFEQT score of + or −5 points are clinically important changes in patients’ health. Clinical Trial Registration: URL: https://clinicaltrials.gov . Unique identifier: NCT01165710.

Background— Antiarrhythmic drugs (AADs) are used to reduce the frequency, severity, and duration of atrial fibrillation (AF) events, which should reduce hospitalizations; however, little is known about the associations between different AADs and hospitalization—particularly among younger AF patients without structural heart disease. Methods and Results— Using MarketScan® claims data, we identified AF patients without coronary artery disease or heart failure who received their first AAD prescription (amiodarone, sotalol, dronedarone, or Class Ic) within 14 days post-first AF encounter. The primary outcome was time from first AAD prescription to AF hospitalization, and secondary outcomes included time to cardiovascular and all-cause hospitalizations. We used inverse probability-weighted estimators to adjust for differences in treatment allocation in the Cox proportional hazards model for each outcome. Among 8562 AF patients with a median age of 56 years (interquartile range 49, 61), risk of AF hospitalization was greater with dronedarone than Class Ic (hazard ratio [HR] 1.59; 95% confidence interval 1.13–2.24), amiodarone (HR 2.63; 1.77–3.89), and sotalol (HR 1.72; 1.17–2.54), but lower with amiodarone versus Class Ic (HR 0.68; 0.57–0.80) and sotalol (HR 0.63; 0.53–0.75). Risk of cardiovascular hospitalization was lower with amiodarone than Class Ic (HR 0.80; 0.70–0.92), but not non-AF cardiovascular hospitalization (HR 1.26; 1.01–1.57). There was no difference in all-cause hospitalization between amiodarone, Class Ic, and sotalol. Conclusions— Differences in hospitalization rates were found between AADs in younger AF patients without structural heart disease. Amiodarone had the lowest risk of AF hospitalization and dronedarone had the greatest risk. Additional research is needed to better understand associations between AADs and hospitalization risk.

Objective: Diabetes is a common among patients with atrial fibrillation (AF). However, little is known on the impact of diabetes on symptoms, health status, care and outcomes among AF patients. We assessed whether symptoms, health status, care and outcomes differ between AF patients with and without diabetes. Methods: This observational cohort study included 9,749 patients with AF from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation registry, a prospective, nationwide, multicenter outpatient registry of patients with incident and prevalent AF enrolled at 174 sites between June 2010 and August 2011. The outcomes were symptoms, health status, and AF treatment, as well as 2-year risks of death, readmission, thrombomebolic events, heart failure (HF) and AF progression. Results: Among AF patients; those with diabetes (29.5%) were younger and more likely to have hypertension, chronic kidney disease, HF, coronary heart disease, and stroke. Patients with diabetes had a lower Atrial Fibrillation Effects on Quality of Life score (80.6 [IQR: 62.5 - 92.6] vs. 82.4 [IQR: 67.6 -93.5]; P = 0.025), but a higher CHA 2 DS 2 -VASc score (5 [IQR: 4 - 6] vs. 4 [2 - 5]; P P Conclusions: Among patients with AF, diabetes was associated with worse AF symptoms and lower quality of life, as well an increased risk of death and hospitalizations, but not with the risk of thromboembolic or bleeding events.

Background: Patient-reported outcomes and satisfaction are important in both trials and clinical practice and may be associated with treatment adherence. Methods: ROCKET-AF was a randomized, double-blind trial of rivaroxaban versus warfarin for prevention of thromboembolism in patients with atrial fibrillation. In a substudy, we compared treatment satisfaction scores: Anti-Clot Treatment Scale (ACTS) and Treatment Satisfaction Questionnaire for Medication version II (TSQM II). Patient-driven discontinuation included stopping study drugs due to withdrawal of consent, non-compliance, or loss to follow-up. Rates of discontinuation were calculated for participants above and below the median scores for each scale. Results: Of 14,264 patients in ROCKET AF, 1,181 (8.3%; median age 75 years; 34% women) patients completed both the ACTS and TSQM II questionnaires 4 weeks after starting the study drug. Over a median follow-up of 1.6 years, 450 premature study drug discontinuations occurred, 116 (26%) patient-driven. Patients less satisfied with treatment by the ACTS Benefits and Burdens and TSQM II scales had higher rates of study drug discontinuation ( Table ). Conclusions: Patient-reported satisfaction was lower in patients with study drug discontinuation, suggesting that collecting patient-reported outcomes early in clinical trials may guide interventions that improve adherence and clinical outcomes.

Introduction: Patient understanding of available therapies for atrial fibrillation (AF) is foundational to shared medical decision making and long term medication adherence. Yet, there is a paucity of data regarding the extent to which patients newly diagnosed with AF in routine community practice understand their options. Hypotheses: 1) Understanding of warfarin, novel oral anticoagulants (NOAC), rhythm control therapy, cardioversion and radio frequency ablation changes little from baseline to 6 months and 2) treatment rates at 6 months are associated with patient understanding of therapies at baseline. Methods: We analyzed survey data from SATELLITE, a substudy of new-onset AF patients enrolled at 56 US sites participating in the ORBIT-AF registry. Patients were surveyed at the baseline and 6 month follow up clinic visit using Likert scales. Agreement between time points was assessed with the McNemar test, and the relationship between understanding and treatment was assessed only for the subset not on treatment at baseline. Results: Of 1000 patients enrolled in SATELLITE, 506 had 6-month survey data (data collection is continuing). Among these, the median age was 69.0 years (IQR 63.0 - 76.0) and 93.7% (474 of 506) were white. There was evidence of improvement in the self-reported understanding of warfarin and NOACs from baseline to 6 months, but not for rhythm control, ablation or cardioversion. The proportion reporting high understanding improved significantly for warfarin (p Conclusions: Patients with new-onset AF had improved self-reported understanding of some treatment options over the first 6-months from diagnosis; however, factors other than patient understanding may influence AF treatments received at 6 months. Patient understanding of AF treatments remains suboptimal at 6 months, and our results suggest a need for ongoing patient education.

Background— Patients with heart failure and atrial fibrillation are at higher risk of thromboembolic events than patients with heart failure alone. Yet, the use of anticoagulation therapy varies in clinical practice, especially among older patients, for whom its effectiveness is poorly understood. Methods and Results— Using clinical registry data linked to Medicare claims from 2005 to 2011, we examined outcomes of older patients hospitalized with heart failure and atrial fibrillation who newly initiated anticoagulation therapy at discharge. We used Cox proportional hazards models and inverse probability-weighted treatment estimates to adjust for selection bias. Main outcomes were mortality and readmission at 1 and 3 years. Among 5105 patients in 195 hospitals, 1623 (31.8%) started anticoagulation therapy at discharge. Treated patients had lower unadjusted rates of all-cause mortality (26.4% versus 42.8%; P P Conclusions— Initiation of anticoagulation therapy at hospital discharge was associated with improved mortality at 1 and 3 years but was not associated with improved cardiovascular readmission among older patients with heart failure and atrial fibrillation.

Background— To evaluate the previously reported excess of thromboembolic events during the 30 days after the end of study (EOS) visit when participants transitioned from blinded therapy to open-label vitamin K antagonist. Methods and Results— At the EOS visit, open-label vitamin K antagonist was recommended, and the international normalized ratio (INR) was not to be measured until 3 days later to preserve blinding. We analyzed transition strategies, clinical outcomes, and INR values. Event rates are per 100 patient-years. A total of 9248 (65%) participants were taking study drug at EOS, and, between days 3 and 30, an excess of stroke and systemic embolic events were observed in participants assigned to rivaroxaban (rivaroxaban 22 events, event rate 6.42; warfarin 6 events, event rate 1.73; hazard ratio, 3.72; 95% confidence interval, 1.51–9.16; P =0.0044). No INR values were reported for ≈5% of participants transitioned to warfarin. By 30 days after EOS, 83% of the warfarin group and 52% of the rivaroxaban group had ≥1 therapeutic INR value. Median time to first therapeutic INR was 3 days in the warfarin group and 13 days in the rivaroxaban group. Conclusions— The excess of events at EOS was likely because of a period of inadequate anticoagulation in rivaroxaban participants switched to vitamin K antagonist therapy. If transition from rivaroxaban to vitamin K antagonist is needed, timely monitoring and careful dosing should be used to ensure consistent and adequate anticoagulation.

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 P 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.

Background: The Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT) survey has recently been validated to measure the impact of atrial fibrillation on patients’ quality of life, but a clinically important difference (CID) in AFEQT score has not been defined. Knowing the CID is needed to interpret the meaningfulness of differences between treatments in clinical trials; or patient populations for quality assessment. Objectives: To calculate CID values in AFEQT in the ORBIT registry. Methods: ORBIT-AF is a US-based outpatient AF registry that measured disease-specific QoL with the AFEQT tool (score range= 0 (worst) to 100) at baseline and at 1 year follow-up. Two anchor-based methods were used to relate changes in AFEQT to clinically important differences in the more established European Heart Rhythm Association (EHRA) measure of functional status. Ranging from 1 (no symptoms) to 4 (disabling), a change of 1 EHRA class was defined as an important change in the anchor. Both the mean change and receiver operating characteristics (ROC) methods were then used to identify CIDs in AFEQT at 1 year follow-up. This was done for both improvement and worsening on the anchor. The mean change method defines a CID as the mean change in AFEQT score among patients with a 1 EHRA class change. The ROC method identifies a CID as the point on the ROC curve that best discriminates patients who experienced an important change in the anchor (≥ 1 EHRA class change) from those who experienced no change. Results: AFEQT was assessed in 2008 AF patients at baseline and 1347 patients at 1 year from 99 US sites participating in ORBIT-AF. CIDs and 95% confidence intervals (CI) corresponding to an improvement in EHRA for the mean change method were 5.4 (3.6, 7.2) AFEQT points and 1.9 (0.4, 9.3) AFEQT points for the ROC method. CIDs corresponding to worsening in EHRA for the mean change method were -4.2 (-6.9,-1.5) AFEQT points and -7.4 (-13.9,-4.6) AFEQT points for the ROC method. Conclusions: Changes in AFEQT as small as 2 points may be clinically relevant, although CIDs vary depending on the method of calculation. The variability suggests identifying a single universal CID to assess improvement in quality of life in AF patients may not be ideal and improvement may relate to the nature of a patient’s symptoms and their baseline level of activity.

Background— Several studies that used claims and registry data have reported that 40% to 80% of patients eligible for an implantable cardioverter defibrillator (ICD) fail to receive one in clinical practice, and the rates are especially high among women and blacks. The extent and documented reasons for nonuse of ICDs among patients with left ventricular systolic dysfunction are unknown. Methods and Results— Using hospital claims and clinical data, we identified patients hospitalized with a heart failure diagnosis and left ventricular ejection fraction ≤30% between January 1, 2007, and August 30, 2007, at a tertiary-care center. Using claims data, we determined placement of an ICD or cardiac resynchronization therapy with defibrillation device at any time up to 1 year after hospitalization. Medical records for patients without an ICD were abstracted to determine reasons for nonuse. Patients with an ICD were compared with patients without an ICD and also with patients without an ICD who did not have any contraindication for an ICD as identified through chart abstraction. Of the 542 potentially eligible patients identified, 224 (41%) did not have an ICD. In the initial adjusted analysis, female sex (odds ratio=1.90; 95% CI, 1.28 to 2.81) and increasing age (odds ratio=1.07; 95% CI, 1.04 to 1.11) were associated with a higher likelihood of not having an ICD. After detailed chart review, of the 224 patients without an ICD, 117 (52%) were ineligible for the device and 38 (17%) patients refused the device, resulting in only 69 (13%) patients eligible for an ICD who failed to receive one. In this subsequent adjusted analysis, remaining factors associated with a higher likelihood of not having an ICD were absence of ventricular arrhythmias (odds ratio=4.93; 95% CI, 2.56 to 9.50), noncardiology hospital service (odds ratio=3.73; 95% CI, 1.98 to 7.04), and lack of health insurance (odds ratio=3.10; 95% CI, 1.48 to 6.46). Conclusions— On the basis of a detailed chart review, the true rate of ICD underuse may be substantially lower than previous estimates. In addition, after accounting for ICD eligibility criteria, patient sex and age disparities in ICD therapy were no longer present.

Background: Little is known about whether insurance status affects the presentation and treatment of patients with atrial fibrillation (AF). Methods: We used data from the ORBIT-AF Registry (2010 - 2011), a national, large outpatient registry, to evaluate clinical characteristics and oral anticoagulation (OAC) use. We examined differences in comorbidities and receipt of OAC among patients enrolled in the Medicaid program at baseline compared with those not enrolled in Medicaid. After restricting to patients who were taking OAC, we compared receipt of novel oral anticoagulants (dabigatran or rivaroxaban) versus warfarin by Medicaid status during 2 years of followup. We used logistic regression models adjusting for demographic and clinical covariates to evaluate baseline OAC receipt by Medicaid status. Results: Of 10,133 patients, N=470 (4.6%) were classified as having Medicaid insurance. Compared with those with other insurance, Medicaid patients were younger (70.0 years; IQR=61.0 - 79.0 vs. 75.0 years; IQR=67.0 - 82.0), more likely to be female (53.0% vs. 41.8%), and less likely to be white (58.7% vs. 90.7%; all p=2, p=2, Medicaid patients were more likely than patients with other insurance to have “unable to adhere/monitor” listed as a contraindication to OAC (p Conclusions: In a contemporary, community-based AF cohort, Medicaid patients had a greater comorbidity burden and higher stroke risk, yet were less likely to receive OAC compared with those with other forms of insurance.

Introduction: Warfarin and non-vitamin K antagonist oral anticoagulants (NOACs) such as dabigatran are effective for the prevention of stroke and systemic embolism in patients with atrial fibrillation (AF). However, few analyses have compared persistence rates of warfarin vs. dabigatran-treated patients. Methods: The ORBIT-AF registry enrolled patients with AF from 173 clinical practices across the US. One-year persistence of warfarin vs. dabigatran was defined as treatment at baseline visit and at 1-year follow-up. Multivariable logistic regression analysis was used to identify characteristics associated with warfarin or NOAC persistent use. Results: At baseline, 6.4% (N=459/7,150) were treated with dabigatran and 93.6% (N=6,691/7,150) with warfarin. Patients treated with warfarin at baseline were older (74 vs. 71, p Conclusion: Persistence rates for warfarin were higher at one year than those on dabigatran. In addition, factors associated with persistence of warfarin include: African American and Hispanic race, type of AF including permanent and persistent, LVH, and CHA2DS2-VASc risk scores ≥ 2.

Introduction: Catheter ablation has emerged as an effective intervention for atrial fibrillation (AF) in specific patient populations. However, less is known about outcomes of AF ablation in community-based cohorts and risk factors for recurrent AF hospitalization following ablation. Methods: Using nationwide administrative data from the Veteran’s Health Administration (VHA), we identified patients with a catheter ablation for AF between 2007-2012 by applying a previously validated algorithm based on outpatient and inpatient diagnosis and procedure codes. We excluded sites with fewer than 30 total procedures in the study period. We evaluated descriptive baseline characteristics, 30-day complications, and 1-year outcomes of stroke, heart failure, recurrent AF, and death. Results: The cohort consisted of 1,202 patients who were predominantly middle-aged (mean age 62.5±8.2), male (97%), and Caucasian (91%). Associated comorbidities included hypertension (76%), diabetes (30%), congestive heart failure (27%), and coronary artery disease (10%). Catheter ablation occurred at a median of 31.4 months following AF diagnosis. Medical management prior to ablation included any history of rate (21%) or rhythm (77%) control or anticoagulation therapy (91%). Following ablation, rhythm control (80%) persisted over a strict rate (18%) control strategy (n=634 patients with two years of follow-up). During the index procedure and at 30 days, vascular complications [32 (2.7%) and 63 (5.2%)] and hematomas [32 (2.7%) and 55 (4.6%)] were the most frequent procedural complications. Other rarer complications were pericardial effusion/tamponade [18 (1.5%) and 34 (2.8%)] and pneumothorax/hemothorax [1(0.08%) and 1(0.08%)]. At one year after ablation (n=885 patients with a full year of follow-up), patients were hospitalized for AF (28.9%), repeat ablation (8.5%), heart failure (4.2%), and stroke (0.5%) with an overall mortality of 2.8%. Compared to the overall cohort, recurrent AF hospitalization at one year was worse for patients less than 75 years of age (29.6%) and for those pursuing a rhythm control strategy (31.2%). Conclusion: Veterans undergoing AF ablation are typically older with more comorbidities than the general AF ablation population. Despite these variations, overall outcomes for AF ablation in the VHA are comparable to outcomes in the general population.

Background: Anticoagulation rates remain suboptimal for patients with atrial fibrillation (AF). Although these rates could potentially be improved with performance measures, there is no universal algorithm for identifying AF patients at risk for stroke using the electronic medical record. Methods: Patients with AF seen between 6/1/2011-5/31/2012 were identified. CHADS¬2 and CHA2DS2-Vasc scores were calculated with a broader algorithm that uses codes dating back 10 years, and a restrictive algorithm requiring comorbidity diagnoses within the past year. The accuracies of a claims-based AF definition and of each of four stroke risk classification algorithms (broad and restrictive each using CHADS¬2 and CHA2DS2-Vasc scores ≥2) were evaluated using data obtained from manual chart reviews for 300 patients. Electronic medication data were used to evaluate rates of anticoagulation among AF patients identified as at risk for stroke. Results: 6397 patients with prevalent AF were identified. Chart reviews confirmed a diagnosis of AF or atrial flutter in 95.7%. Patients with AF at risk for stroke were most accurately assessed using a restrictive algorithm based on a CHA2DS2-Vasc score ≥2 (PPV 97.5%, NPV 65.1%). The PPV of the broader algorithm based on CHADS2 score was 88.0%; 12% of those identified as high-risk electronically had CHADS2 scores Discussion: Automated methods can be used to identify patients with prevalent AF indicated for anticoagulation, but may suffer from misclassification of up to 12%. Misclassification is minimized by requiring a diagnosis of AF within the prior year and using a CHA2DS2-Vasc based algorithm. Despite differences in accuracy between definitions, system-wide anticoagulation rates assessed using these definitions were similar. The diagnosis codes validated in this study can be applied for internal quality improvement and observational studies, and might be adapted for use in nationwide quality reporting programs.

Background: Interruption of OAC is often required for invasive procedures, yet the frequency, management, and outcomes of temporary interruptions (TIs) in community practice are unknown. Methods: We assessed the frequency and reasons for TI in outpatients with AF enrolled in the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF). Patient characteristics and use of bridging anticoagulants were analyzed. Endpoints included periprocedural adverse events (bleeding, thrombotic, or other) and cause-specific hospitalization within 30 days after TI. Results: Overall 7,372 patients were treated with OAC at baseline; 30% (n=2200) required at least 1 TI during median follow-up of 1 year. Patients requiring TI were similar in age (mean age 74 for both) and CHADS2 scores (mean 2.4 for both) to those not requiring TI. Among 3104 interruptions, the most commonly-identified reasons were for non-cardiac surgery (n=827, 27%), followed by endoscopic procedures (n=551, 18%) and cardiac catheterization (n=308, 10%). Bridging anticoagulants were used in 23% (n=709) of interruptions, including low-molecular weight heparin (n=512) or unfractionated heparin (n=109). Rates of bridging were highest during cardiac surgery (44%), cardiac catheterization (32%), and catheter ablation (33%). Patients with a prior stroke or TIA were significantly more likely to receive bridging (35% vs. 25%, p=0.0003), however there was no difference between patients with CHADS2 score >=2 vs. 0-1 (27% vs. 25%, p=NS). Adverse events during interruption were more common in bridged patients (5.1% vs. 2.9%, p=0.02), including bleeding events (3.6% vs. 1.8%, p=0.02); thrombotic events were uncommon (0.7 [n=4] vs. 0.5% [n=10], p=NS). After interruption, adverse events occurred early in follow-up (Figure), and bridged patients were more likely to experience any adverse event (13% vs. 6.3%, p Conclusions: Temporary interruptions are common in patients receiving OAC for AF, however, bridging anticoagulation is used in a minority. Bleeding events following TI occurred significantly more often in patients receiving bridging anticoagulation.

Objective: Time in the therapeutic range (TTR) of INR 2.0-3.0 is an important measurement of warfarin anticoagulation quality. There are few reports on TTR in United States (US) clinical practice. Methods: Using the US ORBIT AF registry, we analyzed TTR for patients on warfarin with at least 5 recorded INR measurements. The Rosendaal method of linear interpolation was used between each pair of measured INR values. Patients were stratified into quartiles based on TTR. Results: We studied 5,451 patients treated at 169 US sites with 48% of patients being followed at an anticoagulation clinic. Patients had a median age of 76 years [interquartile range (IQR) 68-82 years] and median follow-up was 18.9 months [IQR 12.7-23.3 months], and patients were 42% women. The median number of INR draws was 21 [IQR 12-30]. Patients had an overall median TTR of 68% [IQR 52-80%]. The median TTR by quartile was 40%, 60%, 73%, and 87%. Patients were more likely to be subtherapeutic (median time of 17%) than supratherapeutic (median time of 10%). Patients age 61-80 years and those with a college education had the highest TTRs. Patients with their INR followed at an anticoagulation clinic were more likely to be in the highest TTR quartile than in the lowest (27% vs 23%, p=0.0002). Patients with worsening renal function and higher risk for bleeding (ATRIA) or stroke (CHADS2 score) had lower TTR (p Conclusions: In US clinical practices, warfarin patients have therapeutic INR levels about 2/3 of the time. Those at highest risk for stroke and bleeding paradoxically were the least likely to be in the therapeutic range.

Background. Oral anticoagulation therapy (OAC) reduces the risk of thromboembolic events associated with atrial fibrillation (AF), yet a substantial proportion of patients with AF are not prescribed OAC. The frequencies of and factors associated with contraindications to OAC therapy in clinical practice are not well-described. Methods. We used data from the ORBIT-AF study, a national, prospective, outpatient registry of incident and prevalent AF. OAC contraindications were uniformly collected at study enrollment by site personnel. Patient and provider characteristics were compared between participants with documented OAC contraindications at baseline and those without OAC contraindications. Results. From June 2010 to August 2011, 10124 patients ≥18 years old with electrocardiographically documented AF were enrolled at 176 practices. Of these, 1409 (13.9%) had OAC contraindications documented at the baseline visit: prior bleed (26.2%), patient refusal/preference (26.0%), high bleeding risk (22.6%), frequent falls/frailty (16.6%), other (11.9%), need for dual antiplatelet therapy (9.8%), unable to adhere/monitor warfarin (5.7%), comorbid illness (5.0%), prior intracranial hemorrhage (4.7%), allergy (2.3%), occupational risk (0.8%), and pregnancy (0.2%). Compared to patients without contraindications, those with contraindications had higher stroke risk (CHADS2>2) and were older, more likely to be female, more likely to be seen by a cardiologist and less likely to be seen by an electrophysiologist (Table 1). Among those patients with reported contraindications, 28.4% were taking warfarin. Conclusions. Contraindications to OAC therapy among AF patients are common and often due to high bleeding risk. Furthermore, many patients with reported contraindications are taking warfarin, suggesting that many contraindications to warfarin therapy are minor, relative, or temporary.

Background: Dabigatran is a novel oral anticoagulant approved in October 2010 for thromboprophylaxis in atrial fibrillation (AF), yet patterns of adoption of this novel agent in clinical practice are unknown. Methods: Using the ORBIT-AF Registry, a national outpatient prospective AF registry involving 170 sites, we examined patterns of those switching to dabigatran from warfarin from 2010 to 2012. Results: Of 7,066 patients with AF receiving warfarin at baseline, 511 (7%) were switched to dabigatran during follow-up. Patients switched to dabigatran were younger (median age 73 vs. 76, p2 scores were significantly lower (p Conclusions: Patients receiving warfarin who were switched to dabigatran were younger, with lower CHADS 2 scores, better kidney function, and less concomitant cardiovascular disease than those not switched. This conservative transition pattern suggests greater physician emphasis on bleeding avoidance than on stroke risk reduction.

Background. Warfarin reduces the risk of thromboembolic events associated with atrial fibrillation (AF), but therapeutic persistence is suboptimal. Few studies have investigated the reasons for warfarin discontinuation in community practice. Methods. We used data from ORBIT-AF, the nation’s largest AF database, to examine patterns of warfarin discontinuation over a one-year period. Patients transitioned to non-warfarin oral anticoagulation therapy were excluded. We compared patient and provider characteristics between individuals who discontinued warfarin and those who persisted. Results. From June 2010 to August 2011, 10,126 AF patients 18 years or older were enrolled at 176 ORBIT-AF practices. Of these, 6,559 (64.8%) were taking warfarin at baseline and have follow-up data; 514 (7.8%) of these switched to dabigatran and were excluded from the analysis. Additionally, two patients without follow-up warfarin data were excluded from the analysis. Over one year, 587 patients (9.7%) discontinued warfarin therapy. Compared to persistent users, patients who discontinued warfarin were younger, less likely to be white, had lower stroke risk (CHADS 2 Conclusions. Discontinuation of warfarin is common among patients with atrial fibrillation. Patient and physician preference are major contributors to persistence on warfarin therapy.

Background: The use of evidence-based therapies to treat cardiovascular comorbidities and risk factors in patients with AF in outpatient clinical practice has not been well characterized. Methods: Using a large, community-based registry of patients with AF in the United States, the prevalence of cardiovascular comorbidities and corresponding use of evidence-based therapies were determined. Results: Among 9,589 enrolled patients with AF, the median age was 75 years; 57.8% were male; 10.7% were non-white; 69.9% had Medicare or Medicaid; 31.8% had coronary heart disease, 32.2% had heart failure, 13.0% had peripheral vascular disease, and 29.5% had diabetes mellitus. Among eligible patients, 62.8% of 3,612 were prescribed an antiplatelet agent, 72.1% of 4,674 were prescribed a β-blocker, 59.7% of 5,121 were prescribed an angiotensin converting enzyme inhibitor or angiotensin receptor blocker, 15.7% of 624 were prescribed an aldosterone antagonist, 70.1% of 6,914 were prescribed a statin, 94.7% of 8,329 were prescribed an antihypertensive, 58.3% of 504 had an ICD, and 44.5% of 9,589 received all indicated evidence-based therapies ( Table ). Conclusion: Cardiovascular comorbidities and risk factors in patients with AF are often inadequately treated with evidence-based therapies in the outpatient practice setting, underscoring opportunities to improve care for patients with AF.

Background Oral anticoagulation (OAC) can reduce stroke risk at the cost of increased bleeding risk in those with atrial fibrillation (AF). Observational data have shown that higher-risk patients with AF most likely to benefit from OAC are less likely to receive OAC at hospital discharge. Methods We used data from ORBIT-AF Registry, a cohort of 9,589 AF patients enrolled among 173 participating outpatient practices. OAC was defined as warfarin or dabigatran use at study enrollment. Stroke and bleeding risk were calculated using the CHADS2 and ATRIA scores, respectively. Results The study population had a mean age of 73.5 years; 57.8% were men. Overall, 76.4% of patients received OAC. Use of OAC rose with increasing CHADS2 stroke risk, from 67% for CHADS2 Conclusions In community-based outpatients with AF, use of OAC rose with increasing thromboembolic risk and declined with higher bleeding risk. These findings suggest that the risk-treatment paradox may be less that previously reported. Provision of OAC in community practice appears to appropriately consider patients' stroke and bleeding risks. Further research is required to understand how quality improvement initiatives can further improve stroke prevention.

Background: Atrial fibrillation (AF) is the most common heart dysrhythmia and risk increases with advancing age. Guidelines advocate catheter ablation as a treatment for AF in patients who have failed antiarrhythmic drug therapy. However, little is known about outcomes associated with AF ablation in elderly patients. Methods: We obtained administrative claims for all Medicare fee-for-service beneficiaries ≥65 years who underwent intracardiac catheter ablation from 7/1/2007 to 12/31/2009. Outcomes included mortality, stroke/TIA, pericardial effusion, new MI, and vascular complications requiring surgery within 30 days, and mortality, stroke/TIA, heart failure, new hospitalization, and repeat AF ablation within 1 year. We used Kaplan-Meier methods to calculate unadjusted outcome rates overall and by age, and multivariable Cox models to examine predictors of 1-year outcomes. Results: Overall, 15,423 Medicare beneficiaries underwent AF ablation (mean age 72 years, 41% female and 96% white). Common comorbidities included hypertension (78%) and ischemic heart disease (51%). Dementia (0.6%) and stroke/TIA (6%) were relatively rare. Adverse outcomes at 30 days were fairly infrequent, including death (0.8%), stroke/TIA (0.8%), pericardial effusion (2%), MI (0.3%) and vascular complications (0.5%). Within 1 year, 4% of patients died, 43% required new hospitalization, and 11% had repeat ablation. AF or atrial flutter was the primary discharge diagnosis in a minority of new hospitalizations (38%). The death rate among patients aged ≥80 years (10%) was 5 times higher than among patients aged 65-69 years (2%). Whereas stroke/TIA, heart failure and hospitalization (Figure) also increased with age, repeat ablation was more common in younger patients. After multivariable adjustment, renal impairment (HR 2.07 [1.66, 2.58]), advanced age (HR for age ≥ 80 years, =3.09 [2.32, 4.11]), and heart failure (HR 2.54 [2.07, 3.13]) were notable risk factors for 1-year mortality following AF ablation. Conclusion: While major complications following AF ablation were fairly infrequent, new hospitalization was common. Given the association of complications and death with increasing age, randomized trials should inform the risk-benefit of AF ablation for elderly patients.

Objective: Several studies using claims or registry data have reported high rates of under-utilization of ICDs in clinical practice. Women and elderly were reported to be particular subgroups at risk for non-use. We used detailed chart review to determine the true extent of ICD non-use in patients with left ventricular systolic dysfunction. Methods: Using hospital claims and clinical data, we identified patients hospitalized between 1/07 through 8/07 at a tertiary care center with a heart failure (HF) diagnosis and LVEF ≤ 30% who also had follow-up at the same institution. Placement of an ICD or CRT-D up to 1 year after hospitalization was determined. Medical records for patients without an ICD were abstracted to determine reasons for non-use. Results: Of the 542 patients identified as potentially eligible for an ICD, 224 (41%) did not have an ICD up to 1 year after hospitalization. Among these, women (adjusted OR 1.93; 95% CI 1.28-2.93) and those with advanced age (adjusted OR 1.08; 95%CI 1.04-1.12) were more likely to not have an ICD ( Table ). Detailed chart review found that 38 (7%) patients refused an ICD and 117 (22%) were ineligible for an ICD (53 had improvement in EF after index hospitalization, 54 had limited life expectancy, 1 had complicated anatomy precluding ICD implant, and 9 had Class IV HF). Therefore, with only 69 patients found to be eligible for an ICD after chart review, the true rate of ICD non-use was 13%. In this population, factors significantly associated with non-use of an ICD are shown in the Table. Of note, women and those of advanced age were not significantly more likely to be non-recipients of an ICD. Conclusion: Previously reported rates of ICD under-utilization using claims or registry data may be an overestimate. After detailed record review, only 13% of truly eligible hospitalized HF patients failed to receive an ICD. Gender and age differences in ICD use may also be accounted for by ICD eligibility differences. Adjusted Odds Ratios and 95% Confidence Intervals for Characteristics Associated with No ICD Characteristics All ICD Recipients versus All Non-Recipients All ICD Recipients versus Non-Recipients Without Refusal/Contraindication No Ventricular Arrhythmia 3.32 (2.21, 5.00) 5.62 (2.82, 11.11) Index Hospitalization on Non-Cardiology Service 3.36 (2.03, 5.56) 4.59 (2.33, 9.09) Age (per 1 year) 1.08 (1.04, 1.12) 1.02 (1.00, 1.04) Female 1.93 (1.28, 2.93) 1.00 (0.52, 1.92) Qualifying EF (per 1% increase) 1.03 (1.00, 1.07) 1.05 (1.00, 1.10) Days from Qualifying EF to Index Hospital discharge (per 10 days) 0-200 days 200+ days - - 0.92 (0.89, 0.95) 1.01 (1.00, 1.03) - - 0.91 (0.87, 0.97) 1.01 (0.99, 1.03) No Health Insurance 1.58 (0.89, 2.80) 2.96 (1.39, 6.29) African American race 1.38 (0.90, 2.11) 1.27 (0.66, 2.45) Ischemic Heart Disease 1.15 (0.75, 1.75) 1.03 (0.54, 1.94) Diabetes 0.87 (0.65, 1.44) 0.58 (0.32, 1.07)

Background: Little data are available regarding differences in prognosis and health status between new-onset and prior atrial fibrillation (AF) among patients with acute myocardial infarction (AMI). Methods: The TRIUMPH study enrolled 4340 AMI patients who received longitudinal follow-up including SF-12 health status assessments through 1 year post-AMI. We compared 1-year mortality, rehospitalization, and functional status according to AF type (none, prior, new) after adjusting for differences in baseline characteristics. Results: A total of 212 AMI patients (4.9%) had prior AF and 254 (5.9%) had new-onset AF. Compared with no AF, new AF was associated with older age, male sex, first MI, worse baseline physical function, home atrioventricular nodal blocker use, and worse ventricular function (c-index 0.77). Rates of 1-year mortality were 6.2%, 14.5%, and 13.0%, and 1-year rehospitalization rates were 29.1%, 44.2%, and 36.8% for no, prior, and new AF, respectively. After multivariable adjustment, neither prior nor new AF was associated with increased 1-year mortality, and only prior AF was associated with increased risk of 1-year rehospitalization (Figure). After adjusting for baseline SF-12 physical function scores, patients with prior AF had lower 1-year scores than those with no AF (40.6 vs. 43.7, p Conclusion: New-onset AF during AMI is associated with a number of comorbidities but, unlike prior AF, is not associated with adverse outcomes. These results raise the question of whether AF is itself a cause of or simply a marker of comorbidities leading to downstream adverse outcomes after AMI.