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Introduction: Higher body mass index (BMI) is an independent risk factor for incident atrial fibrillation (AF). However, its impact on management strategies and clinical outcomes among patients with prevalent AF is unclear. Methods: The study cohort included patients with AF enrolled in the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF) registry from June 2010 through August 2011. Participants with BMI > 18.5 kg/m2 were stratified into normal (18.5 - 25 kg/m2), overweight (25 - 30 kg/m2), Class I obese (30 - 35 kg/m2), Class II obese (35 - 40 kg/m2), and Class III obese (>40 kg/m2) categories. Unadjusted and adjusted Cox frailty models were constructed to assess the categorical and continuous association of BMI with AF progression, mortality, and incidence of thromboembolic events. Results: We evaluated 9,606 patients with AF (mean age: 74 + 11 years; 42% women) from 174 US ORBIT participating practices. Patients in the higher BMI categories were younger and had a higher prevalence of comorbidities such as diabetes, hypertension, and obstructive sleep apnea. AF symptom burden was greatest among patients in extreme BMI categories. Proportional use of anticoagulation, antiarrhythmic drugs, and invasive rhythm control strategies was significantly greater among patients in higher BMI categories. Rates for mortality and stroke/non-CNS embolism decreased in a near linear fashion across successively higher BMI categories (P<0.001; Table). After multivariable adjustment, higher BMI categories were associated with lower risk for mortality (p = 0.0002), with the lowest risk observed among overweight patients [Hazard Ratio (HR) (95% CI): 0.65 (0.54 - 0.79) ref. group: normal weight]. For every 5-kg/m2 increase in BMI, the odds of risk-adjusted mortality were 6% lower [HR (95% CI): 0.94 (0.89 - 0.98)]. In contrast, the association between BMI and risk for stroke/non-CNS embolism was significant on unadjusted analysis (P <0.001) but attenuated after adjustment for risk factors (P = 0.78; Table). No significant association was observed between BMI and AF progression rates in either unadjusted (P = 0.35) or adjusted analyses (P = 0.17). Conclusion: Among patients with AF, higher BMI was associated with a greater use of anticoagulation, rhythm control strategies, and lower mortality risk.

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<0.0001), cardiovascular hospitalization (4.3% vs. 2.3%, p=0.02), and bleeding hospitalization (2.2% vs. 0.7%, p=0.002) within 30 days. 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.

Background: Health insurance coverage has been recently expanded to millions of Americans with the goal of improving access and quality of care. We evaluated long-term outcomes for patients with ST-elevation myocardial infarction (STEMI) with different insurance types. Methods: From 2004 to 2010, 970 consecutive STEMI patients who presented to 29 hospitals in Minnesota, Iowa or Wisconsin were treated according to the Mayo STEMI protocol. Demographic, clinical, procedural, and long-term follow up data were prospectively collected. 953 patients were categorized into groups by insurance type - private insurance (PI, n=430), Medicare (MC, n=420), Medicaid (MD, n=68), and uninsured (UN, n=35). Results: Median duration of follow-up was 32 months, and mean ages (years) were 55±8 for PI, 75±10 for MC, 49±10 for MD, and 52±9 for UN (p<0.001). Compared to PI patients, MC and MD patients were more likely to have diabetes (both 21% vs 10%, p<0.001); MC patients had more renal failure (4% vs <1%, p=0.012) but UN patients did not differ significantly (DM 12% and CRF 0%). All groups had similar frequency of cardiogenic shock (PI 9%, MC 14%, MD 9%, UN 6%, p=0.08) and comparable door-to-balloon (in minutes(Q1,Q3): PI 69(54,107), MC 79(61,114), MD 83(55,124), UN 76(58,94), p=0.09) and door-to-needle times (in minutes(Q1,Q3): PI 26(19,34), MC 29 (21,39), MD 27(22,34), UN 17(13,21), p=0.06). MC patients had the highest incidence of in-hospital death (7.6%; p=0.003 vs PI 3.0%). Significant differences in all cause mortality between insurance groups were present on 5-year follow-up (Figure). After risk factor adjustment for age (HR 1.89 per decade, p<0.001), female sex (HR 1.16, p=0.40), diabetes (HR 1.89, p<0.001), peripheral artery disease (HR 2.06, p=0.004), heart failure (HR 1.40, p=0.14), cardiogenic shock (4.22, p<0.001) and renal failure (HR 1.62, p=0.20); insurance type was not an independent risk factor for death (p=0.26). When compared to PI, the hazard ratio for UN was associated with a trend for worse survival (HR 2.69, 95%CI 0.94, 7.67, p=0.06) while MC (HR 0.94, 95%CI 0.55, 1.61, p=0.83) and MD patients (HR 1.37, 95%CI 0.52, 3.59, p=0.53) had similar survival after adjustment for covariates. Conclusion: Timeliness of reperfusion was similar across all insurance groups. After adjustment for baseline clinical variables, there was no significant difference in long-term survival according to insurance type.

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, p<0.0001), more likely to be White (94% vs. 89%, p=0.001), and had better kidney function (median creatinine clearance (CrCl) 77 mL/min vs. 69 mL/min, p<0.0001), but less likely to have a history of anemia, (14% vs. 18%, p=0.009) or history of any cerebrovascular disease (14% vs. 17%, p=0.04) or CAD (22% vs. 34%, p<0.0001) or be followed in an anticoagulation clinic (36% vs. 45%, p<0.0001). Patients switched to dabigatran were more likely to have been recently diagnosed with AF (5.3% vs. 3.0%, p=0.03), and their CHADS 2 scores were significantly lower (p<0.0001). 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. 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: CHA2DS2-VASc score has been shown to predict occurrences of incident stroke in patients with history of atrial fibrillation (A-Fib)/ Flutter. However, data on whether if CHA2DS2-VASc score would predict incidence of stroke in patients without A-Fib/ Flutter is less clear. Methods: From 1993 through 2010, all patients undergoing a clinically indicated treadmill exercise test (TMET) at the Mayo Clinic, Rochester, MN were identified (N= 76,857). From this, Olmsted and neighboring counties residents were selected (N=14,095). From this, patients with age <18 years; prior history of valvular heart disease or A-Fib/ Flutter were excluded. Patient undergoing only Bruce or accelerated Naughton protocols on TMET were considered. Patients were stratified into 4 groups at baseline based on CHA2DS2-VASc score as determined at the time of TMET; group-0 score=0; group-I=1; group-2=2; group-3≥3. Patients were prospectively followed from the date of TMET until end of January 2016 for occurrence of incident stroke (ischemic and hemorrhagic). Stroke diagnosis was ascertained through retrospective chart review. Traumatic intracranial bleed was not considered. Proportional hazard regression modeling was done to assess relationship of CHA2DS2-VASc score with the stroke outcome while adjusting for METs achieved, sex, obesity, smoking status, and other relevant risk factors. Results: Final study population comprised of 12,624 patients with female comprising 37% of the cohort. Mean age in our study group was 52.2 ± 12.8 years. During an overall median follow-up of 14 (8 to 17) years, 1,255 (9.9%) patients developed incident stroke. While using CHA2DS2-VASc group-3 as referent, patients in CHA2DS2-VASc group-0 [0.18(0.14-0.23, p<.001)], group-1[0.33 (0.28-0.39, p<.001)], and group-2 [0.50 (0.43-0.58, p<.001)] were at significantly lower risk of developing stroke. Each increase of one point on the CHA2DS2-VASc scale was associated with a 51% [1.51(1.45-1.58, p<.001)] increase in incidence of stroke. Conclusion: CHA2DS2-VASc score predicts incidence of stroke in patients without history of A-Fib/ Flutter.

Introduction: Randomized trials have not demonstrated significant differences in stroke, heart failure or mortality between rhythm and rate control strategies for management of atrial fibrillation (AF). The comparative outcomes in contemporary clinical practice are not well described. The objective of this study was to evaluate outcomes in clinical practice with rhythm control versus rate control strategy. Methods: Patients managed with a rhythm control strategy targeting maintenance of sinus rhythm were retrospectively compared with a strategy of rate control alone in a AF registry across various US practice settings. Unadjusted and adjusted (inverse-propensity weighted) outcomes were estimated. Results: The overall study population (n=6988) had a median age of 74 (25th, 75th percentile 65, 81) years, 56% were males, 77% had first detected or paroxysmal AF and 89% had CHA2DS2-VASc score ≥2. In unadjusted analyses, rhythm control was associated with lower all-cause death, cardiovascular death, first stroke/non-central nervous system systemic embolization/transient ischemic attack, or first major bleeding event (all p<0.05); however, rhythm control was associated with more cardiovascular hospitalizations (HR 1.24, 95% CI 1.10-1.39, p=0.0003; Figure). Conclusion: Among patients with AF in clinical practice, rhythm control was not superior to rate control strategy for outcomes of stroke, heart failure, or mortality, but was associated with more cardiovascular hospitalizations.

Background: Little information exists on clinical characteristics and treatment patterns of patients with atrial fibrillation (AF) following a major bleeding event in clinical practice. Methods: We used data from a large, national outpatient registry, ORBIT-AF (2010 – 2011), to evaluate event characteristics and oral anticoagulation (OAC) management following a major bleeding event. Major bleeds were defined according to ISTH criteria. We compared baseline characteristics among patients who persisted on OAC therapy at the first clinic visit following a major bleed and those in whom OAC was discontinued using chi-squared tests. Results: Of 10135 patients enrolled in ORBIT-AF, n=791 (7.8%) bleeding events occurred during 2 years of follow-up. Among patients who were receiving OA, n=632 (3.5 per 100 person years) experienced a major bleed. Of these, 67.3% experienced a fall in hemoglobin and 46.8% required transfusion of 2 of more units of red blood cells. Critical site bleeding occurred in 150 OAC patients, with the majority of these classified as intracranial bleeding (n= 89), followed by retroperitoneal (n=25) and intraocular (n=17). Fatal bleeds occurred in 37 patients (5.9% of all major bleeds). Nearly one-third of patients (31.0%) discontinued OAC therapy following the major bleeding event. Compared with those who persisted on OAC, patients who discontinued OAC were more likely to have hypertension and CKD. Those who discontinued OAC were more likely to have gastrointestinal or CNS site bleeding compared with those who persisted (Table). Conclusions: One in three patients who experienced a major bleed were no longer optimally anticoagulated after the event. Those who discontinued OAC had a greater comorbidity burden and more likely to have bleeding in a critical site those who persisted on OAC.

Background: There are limited data on uninsured patients presenting with acute myocardial infarction-cardiogenic shock (AMI-CS). This study sought to compare the management and outcomes of AMI-CS between uninsured and privately insured individuals. Methods: Using the National Inpatient Sample (2000–2016), a retrospective cohort of adult (≥18 years) uninsured admissions (primary payer—self-pay or no charge) were compared with privately insured individuals. Interhospital transfers were excluded. Outcomes of interest included in-hospital mortality, temporal trends in admissions, use of cardiac procedures, do-not-resuscitate status, palliative care referrals, and resource utilization. Results: Of 402 182 AMI-CS admissions, 21 966 (5.4%) and 93 814 (23.3%) were uninsured and privately insured. Compared with private insured individuals, uninsured admissions were younger, male, from a lower socioeconomic status, had lower comorbidity, higher rates of acute organ failure, ST-segment elevation AMI-CS (77.3% versus 76.4%), and concomitant cardiac arrest (33.8% versus 31.9%; all P <0.001). Compared with 2000, in 2016, there were more uninsured (adjusted odds ratio, 1.15 [95% CI, 1.13–1.17]; P <0.001) and less privately insured admissions (adjusted odds ratio, 0.85 [95% CI, 0.83–0.87]; P <0.001). Uninsured individuals received less frequent coronary angiography (79.5% versus 81.0%), percutaneous coronary intervention (60.8% versus 62.2%), mechanical circulatory support (54% versus 55.5%), and had higher palliative care (3.8% versus 3.2%) and do-not-resuscitate status use (4.4% versus 3.2%; all P <0.001). Uninsured admissions had higher in-hospital mortality (adjusted odds ratio, 1.62 [95% CI, 1.55–1.68]; P <0.001) and resource utilization. Conclusions: Uninsured individuals have higher in-hospital mortality and lower use of guideline-directed therapies in AMI-CS compared with privately insured individuals.