Peak frequency mapping of atypical atrial flutter.

INTRODUCTION: Peak frequency (PF) mapping is a novel method that may identify critical portions of myocardial substrate supporting reentry. The aim of this study was to describe and evaluate PF mapping combined with omnipolar voltage mapping in the identification of critical isthmuses of left atrial (LA) atypical flutters. METHODS AND RESULTS: LA omnipolar voltage and PF maps were generated in flutter using the Advisor HD-Grid catheter (Abbott) and EnSite Precision Mapping System (Abbott) in 12 patients. Normal voltage was defined as ≥0.5 mV, low-voltage as 0.1-0.5 mV, and scar as <0.1 mV. PF distributions were compared with ANOVA and post hoc Tukey analyses. The 1 cm radius from arrhythmia termination was compared to global myocardium with unpaired t-testing. The mean age was 65.8 ± 9.7 years and 50% of patients were female. Overall, 34 312 points were analyzed. Atypical flutters most frequently involved the mitral isthmus (58%) or anterior wall (25%). Mean PF varied significantly by myocardial voltage: normal (335.5 ± 115.0 Hz), low (274.6 ± 144.0 Hz), and scar (71.6 ± 140.5 Hz) (p < .0001 for all pairwise comparisons). All termination sites resided in low-voltage regions containing intermediate or high PF. Overall, mean voltage in the 1 cm radius from termination was significantly lower than the remaining myocardium (0.58 vs. 0.95 mV, p < .0001) and PF was significantly higher (326.4 vs. 245.1 Hz, p < .0001). CONCLUSION: Low-voltage, high-PF areas may be critical targets during catheter ablation of atypical atrial flutter.

Advances in Cardiac Electrophysiology.

Despite the global COVID-19 pandemic, during the past 2 years, there have been numerous advances in our understanding of arrhythmia mechanisms and diagnosis and in new therapies. We increased our understanding of risk factors and mechanisms of atrial arrhythmias, the prediction of atrial arrhythmias, response to treatment, and outcomes using machine learning and artificial intelligence. There have been new technologies and techniques for atrial fibrillation ablation, including pulsed field ablation. There have been new randomized trials in atrial fibrillation ablation, giving insight about rhythm control, and long-term outcomes. There have been advances in our understanding of treatment of inherited disorders such as catecholaminergic polymorphic ventricular tachycardia. We have gained new insights into the recurrence of ventricular arrhythmias in the setting of various conditions such as myocarditis and inherited cardiomyopathic disorders. Novel computational approaches may help predict occurrence of ventricular arrhythmias and localize arrhythmias to guide ablation. There are further advances in our understanding of noninvasive radiotherapy. We have increased our understanding of the role of His bundle pacing and left bundle branch area pacing to maintain synchronous ventricular activation. There have also been significant advances in the defibrillators, cardiac resynchronization therapy, remote monitoring, and infection prevention. There have been advances in our understanding of the pathways and mechanisms involved in atrial and ventricular arrhythmogenesis.

Social Media Influence Does Not Reflect Scholarly or Clinical Activity in Real Life.

BACKGROUND: Social media has become a major source of communication in medicine. We aimed to understand the relationship between physicians' social media influence and their scholarly and clinical activity. METHODS: We identified attending US electrophysiologists on Twitter. We compared physician Twitter activity to (1) scholarly publication record (h-index) and (2) clinical volume according to Centers for Medicare and Medicaid Services. The ratio of observed versus expected (obs/exp) Twitter followers was calculated based on each scholarly (K-index) and clinical activity. RESULTS: We identified 284 physicians, with mean Twitter age of 5.0 (SD, 3.1) years and median 568 followers (25th, 75th: 195, 1146). They had a median 34.5 peer-reviewed articles (25th, 75th: 14, 105), 401 citations (25th, 75th: 102, 1677), and h-index 9 (25th, 75th: 4, 19.8). The median K-index was 0.4 (25th, 75th: 0.15, 1.0), ranging from 0.0008 to 29.2. The median number of electrophysiology procedures was 77 (25th, 75th: 0, 160) and evaluation and management visits 264 (25th, 75th: 59, 516) in 2017. The top 1% electrophysiologists for followers accounted for 20% of all followers, 17% of status updates, had a mean h-index of 6 (versus 15 for others, P=0.3), and accounted for 1% of procedural and evaluation and management volumes. They had a mean K-index of 21 (versus 0.77 for others, P<0.0001) and clinical obs/exp follower ratio of 17.9 and 18.1 for procedures and evaluation and management (P<0.001 each, versus others [0.81 for each]). CONCLUSIONS: Electrophysiologists are active on Twitter, with modest influence often representative of scholarly and clinical activity. However, the most influential physicians appear to have relatively modest scholarly and clinical activity.

Artificial Intelligence and Machine Learning in Arrhythmias and Cardiac Electrophysiology.

Artificial intelligence (AI) and machine learning (ML) in medicine are currently areas of intense exploration, showing potential to automate human tasks and even perform tasks beyond human capabilities. Literacy and understanding of AI/ML methods are becoming increasingly important to researchers and clinicians. The first objective of this review is to provide the novice reader with literacy of AI/ML methods and provide a foundation for how one might conduct an ML study. We provide a technical overview of some of the most commonly used terms, techniques, and challenges in AI/ML studies, with reference to recent studies in cardiac electrophysiology to illustrate key points. The second objective of this review is to use examples from recent literature to discuss how AI and ML are changing clinical practice and research in cardiac electrophysiology, with emphasis on disease detection and diagnosis, prediction of patient outcomes, and novel characterization of disease. The final objective is to highlight important considerations and challenges for appropriate validation, adoption, and deployment of AI technologies into clinical practice.

Phrenic Nerve Stimulation for the Treatment of Central Sleep Apnea: A Pooled Cohort Analysis.

STUDY OBJECTIVES: Early evidence with transvenous phrenic nerve stimulation (PNS) demonstrates improved disease severity and quality of life (QOL) in patients with central sleep apnea (CSA). The goal of this analysis is to evaluate the complete prospective experience with PNS in order to better characterize its efficacy and safety, including in patients with concomitant heart failure (HF). METHODS: Using pooled individual data from the pilot (n = 57) and pivotal (n = 151) studies of the remede System in patients with predominant moderate to severe CSA, we evaluated 12-month safety and 6- and 12-month effectiveness based on polysomnography data, QOL, and cardiac function. RESULTS: Among 208 combined patients (June 2010 to May 2015), a remede device implant was successful in 197 patients (95%), 50/57 pilot study patients (88%) and 147/151 pivotal trial patients (97%). The pooled cohort included patients with CSA of various etiologies, and 141 (68%) had concomitant HF. PNS reduced apnea-hypopnea index (AHI) at 6 months by a median of -22.6 episodes/h (25th and 75th percentile; -38.6 and -8.4, respectively) (median 58% reduction from baseline, P < .001). Improvement in sleep variables was maintained through 12 months of follow-up. In patients with HF and ejection fraction ≤ 45%, PNS was associated with improvement in systolic function from 27.0% (23.3, 36.0) to 31.1% (24.0, 41.5) at 12 months (P = .003). In the entire cohort, improvement in QOL was concordant with amelioration of sleep measures. CONCLUSIONS: Transvenous PNS significantly improves CSA severity, sleep quality, ventricular function, and QOL regardless of HF status. Improvements, which are independent of patient compliance, are sustained at 1 year and are associated with acceptable safety.

Selective Serotonin Reuptake Inhibitors and Bleeding Risk in Anticoagulated Patients With Atrial Fibrillation: An Analysis From the ROCKET AF Trial.

Background There is concern that selective serotonin reuptake inhibitors ( SSRI s) substantially increase bleeding risk in patients taking anticoagulants. Methods and Results We studied 737 patients taking SSRI s in the ROCKET AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Embolism and Stroke Trial in Atrial Fibrillation) trial of rivaroxaban compared with warfarin for the prevention of stroke/systemic embolism in patients with atrial fibrillation. These patients were propensity score matched 1:1 to 737 patients not taking SSRI s. The primary outcome measure was major and nonmajor clinically relevant bleeding events, the principal safety outcome in ROCKET AF . Over a mean 1.6 years of follow-up, the rate of major/ nonmajor clinically relevant bleeding was 18.57 events/100 patient-years for SSRI users versus 16.84 events/100 patient-years for matched comparators, adjusted hazard ratio ( aHR ) of 1.16 (95% confidence interval [CI], 0.95-1.43). The aHR s were similar in patients taking rivaroxaban ( aHR 1.11 [95% CI, 0.82-1.51]) and those taking warfarin ( aHR 1.21 [95% CI, 0.91-1.60]). For the rarer outcome of major bleeding, the aHR for SSRI users versus those not taking SSRI s was 1.13 (95% CI, 0.62-2.06) for rivaroxaban; for warfarin, the aHR was higher, at 1.58 (95% CI , 0.96-2.60) but not statistically significantly elevated. Conclusions We found no significant increase in bleeding risk when SSRI s were combined with anticoagulant therapy, although there was a suggestion of increased bleeding risk with SSRI s added to warfarin. While physicians should be vigilant regarding bleeding risk, our results provide reassurance that SSRI s can be safely added to anticoagulants in patients with atrial fibrillation . Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 00403767.

Obstructive sleep apnea is associated with increased rotor burden in patients undergoing focal impulse and rotor modification guided atrial fibrillation ablation.

Aims: To assess whether obstructive sleep apnea (OSA) was associated with increased rotor burden among atrial fibrillation (AF) patients. Methods and results: We studied 33 consecutive patients who were scheduled for focal impulse and rotor modulation (FIRM) ablation at our institution to describe the mapping, ablation, and outcomes, among patients with and without OSA. Patients underwent biatrial FIRM mapping in AF with ablation of stable rotors in addition to conventional ablation lesion sets. Differences between groups were tested with student's t-tests and Fisher's exact tests, as appropriate. Survival analyses were performed using the Kaplan-Meier method. Twelve of the 33 (36%) patients had OSA and 8 (66%) used continuous positive airway pressure ventilation (CPAP). Obstructive sleep apnea patients had a higher body mass index (BMI) (33.6 vs. 28.8 kg/m2, P = 0.01) and were more commonly on beta blockers (67% vs. 29%, P = 0.03) but were otherwise similar regarding baseline characteristics, medication use, and prior AF treatments, including antiarrhythmic drugs and prior ablation. Focal impulse and rotor modulation mapping demonstrated increased rotor burden in the OSA patients (2.6 ± 0.9 vs. 2.0 ± 1.0, P =0.03). The increased rotor burden was more evident in the right atrium (RA) (1.0 ± 0.7 vs. 0.5 ± 0.7, P =0.04 compared with left atrium (1.7 ± 0.8 vs. 1.4 ± 0.7, P = 0.15). There was no correlation between BMI and total number of rotors (r = 0.0961, P = 0.59). Among the population of patients with OSA, CPAP therapy was associated with a lower number of RA rotors (0.8 ± 0.7 vs. 1.5 ± 0.6, P = 0.05) but no significant difference in overall rotors (P = 0.33). Conclusion: Obstructive sleep apnea patients demonstrate increased rotor prevalence, driven predominantly by an increase in RA rotors. CPAP therapy was associated with fewer RA rotors.

Outcome of Patients Receiving Thrombolytic Therapy While on Rivaroxaban for Nonvalvular Atrial Fibrillation (from Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation).

The safety of intravenous thrombolysis in patients taking rivaroxaban has not been well established. We retrospectively analyzed the outcomes of all patients who received thrombolytic therapy in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF). A review of medical and adverse event records for patients receiving thrombolytic therapy while enrolled in ROCKET AF was performed to determine their baseline characteristics, indications for thrombolysis, and type of agent used. Safety end points were 30-day post-thrombolytic rates of stroke, bleeding, and mortality. A total of 28 patients in ROCKET AF received thrombolytic therapy, with 19 patients on rivaroxaban and 9 patients on warfarin. Ischemic stroke was the most common indication for thrombolysis (n = 10), and alteplase was the most commonly used fibrinolytic agent (n = 14). Of the 19 patients in the rivaroxaban group, there were 2 nonfatal bleeding events and 2 deaths, mostly occurring when thrombolytic therapy was administered within 48 hours of the last rivaroxaban dose. Of the 9 patients in the warfarin group, there was 1 nonfatal bleeding event and 3 deaths, most occurring when thrombolytic therapy was administered outside of 48 hours from the last warfarin dose. In conclusion, these observations suggest that careful assessment of the time since the last dose may be of clinical significance in patients on novel oral anticoagulants who require emergent thrombolysis.

Factors associated with non-vitamin K antagonist oral anticoagulants for stroke prevention in patients with new-onset atrial fibrillation: Results from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation II (ORBIT-AF II).

BACKGROUND: Several non-vitamin K antagonist oral anticoagulant (NOAC) alternatives to warfarin are available for stroke prevention in atrial fibrillation (AF). We aimed to describe the factors associated with selection of NOACs versus warfarin in patients with new onset AF. METHODS: The ORBIT-AF II study is a national, US, prospective, observational, cohort study of anticoagulation treatment in patients with AF receiving NOACs or warfarin in the United States from 2013 to 2016. We measured factors associated with oral anticoagulant selection in 4,670 patients recently diagnosed with AF. RESULTS: At baseline, 1,169 (25%) patients were started on warfarin and 3,501 (75%) on NOACs: of these latter, 259 (6%) were started on dabigatran, 1858 (40%) on rivaroxaban, and 1384 (30%) on apixaban. Those receiving NOACs were slightly younger patients (median age 71 vs 72, P<.0001); were less likely to have prior stroke (5.3% vs 8.6%; P<.0001) or prior bleeding (2.7% vs 4.4%; P=.005); had better kidney function (mean estimated glomerular filtration rate 91 mL/min vs 80 mL/min, P<.0001); and had fewer patients at high stroke risk (CHA2DS2-VASc score [Congestive heart failure, Hypertension, Age ≥75years, Diabetes mellitus, Prior stroke, transient ischemic attack {TIA}, or thromboembolism,Vascular disease, Age 65-74years, Sex category {female}] ≥2 in 86% vs 93%; P<.0001). In multivariable analysis, factors associated with NOAC selection versus warfarin included renal function, prior stroke or valve replacement, rhythm control AF management strategy, treatment by a cardiologist, and higher patient education level. CONCLUSIONS: In contemporary clinical practice, up to three-fourths of patients with new-onset AF are now initially treated with a NOAC for stroke prevention. Those selected for NOAC treatment had lower stroke and bleeding risk profiles, were more likely treated by cardiologists, and had higher socioeconomic status. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01701817.

Efficacy and safety of rivaroxaban versus warfarin in patients from mainland China with nonvalvular atrial fibrillation: A subgroup analysis from the ROCKET AF trial.

BACKGROUND: The ROCKET AF study evaluated once-daily rivaroxaban versus dose-adjusted warfarin for the prevention of stroke and systemic embolism in patients with atrial fibrillation (AF). In this analysis, we compared rivaroxaban with warfarin in patients with AF from China, East Asia, and the rest of the world (ROW). METHODS AND RESULTS: We assessed baseline demographics and interaction of treatment effects of rivaroxaban versus warfarin among patients from mainland China, other East Asian countries, and ROW. Of the 14,236 patients enrolled in the per-protocol population, 495 were from mainland China, 433 from other East-Asian regions, and 13,308 from the rest of the world (ROW). At baseline, patients from China had significantly higher rates of previous stroke/transient ischemic attack (TIA) compared with patients from other East Asian regions and ROW (79.6%, 44.6%, 51.6% respectively; p<0.0001) and lower rates of VKA use (33.7%, 66.7%, 63.4%, respectively; p<0.0001). The rates of stroke or systemic embolism among those on warfarin while on treatment was 5.23% in patients from China, 1.82% in those from other East Asian regions, and 2.07% from ROW; on rivaroxaban, the rates were 2.29% in patients from China, 1.86% in those from other east Asian regions, and 1.67% from ROW. There were no significant treatment-by-region interactions for any efficacy or safety outcome (all p>0.12). Numerically higher rates of intracranial bleeding were seen in patients from China receiving warfarin versus rivaroxaban. CONCLUSIONS: In patients from China, rates of intracranial hemorrhage were numerically lower among those receiving rivaroxaban and consistent with the overall trial. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT00403767.

Use of concomitant aspirin in patients with atrial fibrillation: Findings from the ROCKET AF trial.

BACKGROUND: We aimed to investigate the relationship between aspirin use and clinical outcomes in patients enrolled in Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF), in particular, those with known coronary artery disease (CAD). METHODS: Patients in ROCKET AF, comparing rivaroxaban and warfarin, were analyzed. Aspirin use was assessed at baseline. Stroke and systemic embolism, myocardial infarction, death, and major or nonmajor clinically relevant (NMCR) bleeding were compared between groups. Multivariable modeling was done adjusting for baseline risk factors. RESULTS: A total of 5,205 (36.5%) patients were receiving aspirin at baseline (mean dose 99.2mg); 30.6% of those had known CAD. Patients receiving aspirin were more likely to have prior myocardial infarction (22% vs 14%; P<.001) and heart failure (68% vs 59%; P<.001). Relative efficacy of rivaroxaban versus warfarin was similar with and without aspirin use for both stroke/systemic embolism (P=.95 for interaction), and major or NMCR bleeding (P=.76 for interaction). After adjustment, aspirin use was associated with similar rates of stroke/systemic embolism (hazard ratio [HR] 1.16, 95% CI 0.98-1.37; P=.094) but higher rates of all-cause death (HR 1.27, 95% CI 1.13-1.42; P<.0001) and major or NMCR bleeding (HR 1.32, 95% CI 1.21-1.43; P<.0001). There was a significant interaction between no CAD at baseline and aspirin for all-cause death (P=.009). CONCLUSIONS: Aspirin use at baseline was associated with an increased risk for bleeding and all-cause death in ROCKET AF, a risk most pronounced in patients without known CAD. Although these findings may reflect unmeasured clinical factors, further investigation is warranted to determine optimal aspirin use in patients with AF.

Use of Dual Antiplatelet Therapy and Patient Outcomes in Those Undergoing Percutaneous Coronary Intervention: The ROCKET AF Trial.

OBJECTIVES: The authors assessed the use of dual antiplatelet therapy (DAPT) and outcomes in patients undergoing percutaneous coronary intervention (PCI) during the ROCKET AF (Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation). BACKGROUND: The frequency, patterns, and outcomes when adding DAPT to non-vitamin K antagonist oral anticoagulants in the setting of PCI in patients with AF are largely unknown. METHODS: The study population included all patients in the treatment group of the ROCKET AF trial divided by the receipt of PCI during follow-up. Clinical characteristics, PCI frequency, and rates of DAPT were reported. Clinical outcomes were adjudicated independently as part of the trial. RESULTS: Among 14,171 patients, 153 (1.1%) underwent PCI during a median 806 days of follow-up. Patients treated with rivaroxaban were significantly less likely to undergo PCI compared with warfarin-treated patients (61 vs. 92; p = 0.01). Study drug was continued during PCI in 81% of patients. Long-term DAPT (≥30 days) was used in 37% and single antiplatelet therapy in 34%. A small number switched from DAPT to monotherapy within 30 days of PCI (n = 19 [12.3%]) and 15% of patients received no antiplatelet therapy after PCI. Rates of stroke/systemic embolism and major bleeding events were high in post-PCI patients (4.5/100 patient-years and 10.2/100 patient-years) in both treatment groups. CONCLUSIONS: In patients with AF at moderate to high risk for stroke, PCI occurred in <1% per year. DAPT was used in a variable manner, with the majority of patients remaining on study drug after PCI. Rates of both thrombotic and bleeding events were high after PCI, highlighting the need for studies to determine the optimal antithrombotic therapy.

Blood pressure control and stroke or bleeding risk in anticoagulated patients with atrial fibrillation: Results from the ROCKET AF Trial.

BACKGROUND: We conducted a retrospective analysis examining the association between systolic blood pressure (SBP) or hypertension bracket and stroke risk in patients with atrial fibrillation (AF). METHODS: The study included 14,256 anticoagulated patients in the ROCKET AF trial. Cox proportional hazards models were used to compare the risk of adverse outcomes by European Society of Cardiology hypertension bracket and screening SBP. RESULTS: In total, 90.5% of patients had hypertension (55.8% controlled, 34.6% uncontrolled). The adjusted risk of stroke or systemic embolism (SE) increased significantly for every 10-mm Hg increase in screening SBP (hazard ratio [HR] 1.07, 95% CI 1.02-1.13). There was a trend toward an increased adjusted risk of stroke or SE in patients with controlled (HR 1.22, 95% CI 0.89-1.66) and uncontrolled hypertension (HR 1.42, 95% CI 1.03-1.95) (P = .06). In contrast, the adjusted risk of major bleeding was similar between hypertensive brackets and did not vary significantly by screening SBP. The benefit of rivaroxaban versus warfarin in preventing stroke or SE was consistent among patients regardless of SBP (P interaction = .69). CONCLUSIONS: In a trial of anticoagulated patients with AF, increasing screening SBP was independently associated with stroke and SE, and one-third of patients had uncontrolled hypertension. The relative effectiveness and safety of rivaroxaban versus warfarin were consistent across all levels of screening SBP. A single SBP may be an important factor in reducing the overall risk of stroke and SE in anticoagulated patients with AF.

On-Treatment Outcomes in Patients With Worsening Renal Function With Rivaroxaban Compared With Warfarin: Insights From ROCKET AF.

BACKGROUND: Despite rapid clinical adoption of novel anticoagulants, it is unknown whether outcomes differ among patients with worsening renal function (WRF) taking these new drugs compared with warfarin. We aimed to determine whether the primary efficacy (stroke or systemic embolism) and safety (major bleeding and nonmajor clinically relevant bleeding) end points from the ROCKET AF trial (Rivaroxaban Once-Daily, Oral, Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation trial) differed among participants with WRF taking rivaroxaban and those taking warfarin. METHODS: After excluding patients without at least 1 follow-up creatinine measurement (n=1624), we included all remaining patients (n=12 612) randomly assigned to either rivaroxaban or dose-adjusted warfarin. On-treatment WRF (a decrease of >20% from screening creatinine clearance measurement at any time point during the study) was evaluated as a time-dependent covariate in Cox proportional hazards models. RESULTS: Baseline characteristics were generally similar between patients with stable renal function (n=9292) and WRF (n=3320). Rates of stroke or systemic embolism, myocardial infarction, and bleeding were also similar, but WRF patients experienced a higher incidence of vascular death versus stable renal function (2.21 versus 1.41 events per 100 patient-years; P=0.026). WRF patients who were randomized to receive rivaroxaban had a reduction in stroke or systemic embolism compared with those taking warfarin (1.54 versus 3.25 events per 100 patient-years) that was not seen in patients with stable renal function who were randomized to receive rivaroxaban (P=0.050 for interaction). There was no difference in major or nonmajor clinically relevant bleeding among WRF patients randomized to warfarin versus rivaroxaban. CONCLUSIONS: Among patients with on-treatment WRF, rivaroxaban was associated with lower rates of stroke and systemic embolism compared with warfarin, without an increase in the composite bleeding end point. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00403767.

Efficacy and Safety of Non-Vitamin K Antagonist Oral Anticoagulants After Cardioversion for Nonvalvular Atrial Fibrillation.

BACKGROUND: Non-vitamin K oral anticoagulants (NOACs) are proven alternatives to vitamin K antagonists (VKAs) for the prevention of thromboembolism in patients with nonvalvular atrial fibrillation. However, there are few data on the efficacy and safety of NOAC therapy after cardioversion, where the risk of thromboembolic events is heightened. METHODS: We performed a random-effects meta-analysis of patients who underwent both electrical and pharmacologic cardioversion for atrial fibrillation in the RE-LY, ROCKET-AF, ARISTOTLE, ENGAGE AF-TIMI 48, and X-VeRT trials. We assessed Mantel-Haenszel pooled estimates of risk ratio (RR) and 95% confidence intervals (CIs) for stroke/systemic embolism and major bleeding at ≤42 days of follow-up. RESULTS: The analysis pooled 3949 patients in whom a total of 4900 cardioversions for atrial fibrillation were performed. Compared with VKAs, NOAC therapy was associated with a similar risk of stroke/systemic embolism (RR 0.84; 95% CI, 0.34-2.04) and major bleeding (RR 1.12; 95% CI, 0.52-2.42); no significant statistical heterogeneity was found among studies (Cochrane Q P = .59, I(2) = 0% for stroke/systemic embolism; P = .47; I(2) = 0% for major bleeding). CONCLUSIONS: The short-term incidences of thromboembolic and major hemorrhagic events after cardioversion on NOACs were low and comparable to those observed on dose-adjusted VKA therapy. Non-vitamin K oral anticoagulants are a reasonable alternative to VKAs in patients undergoing cardioversion.

Clinical Characteristics, Oral Anticoagulation Patterns, and Outcomes of Medicaid Patients With Atrial Fibrillation: Insights From the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF I) Registry.

BACKGROUND: Whereas insurance status has been previously associated with care patterns, little is currently known about the association between Medicaid insurance and the clinical characteristics, treatment, or outcomes of patients with atrial fibrillation (AF). METHODS AND RESULTS: We used data from adults with AF enrolled in the Outcomes Registry for Better Informed Treatment of AF (ORBIT-AF), a national outpatient registry conducted at 176 community, multispecialty sites. The primary outcome of interest was the proportion of patients prescribed any oral anticoagulation (OAC; warfarin or novel oral anticoagulants [NOAC]). Secondary outcomes of interest included the proportion of patients prescribed NOACs (dabigatran or rivaroxaban); time in therapeutic range (TTR) for warfarin users, all-cause mortality, stroke/systemic embolism, and major bleed. Of 10 133 patients, N=470 (4.6%) had Medicaid insurance. Medicaid patients were similarly likely to receive OAC at baseline (72.8% vs 76.3%; unadjusted P=0.079), but less likely to receive NOAC at baseline or follow-up (12.1% vs 16.3%; unadjusted P=0.019). After risk adjustment, Medicaid status was associated with lower use of OAC at baseline among patients with high stroke risk (odds ratio [OR]=0.68; 95% CI=0.49, 0.94), but was not associated with OAC use overall (OR=0.82; 95% CI=0.61, 1.09). Among warfarin users, median TTR was lower among Medicaid patients (60% vs 68%; P<0.0001; adjusted TTR difference, -2.9; 95% CI=-5.7, -0.2; P=0.04). Use of an NOAC over 2 years of follow-up was not statistically different by insurance. Compared with non-Medicaid patients, Medicaid patients had higher unadjusted rates of mortality, stroke/systemic embolism, and major bleeding; however, these differences were attenuated following adjustment for clinical characteristics. CONCLUSIONS: In a contemporary AF cohort, use of OAC overall and use of NOACs were not significantly lower among Medicaid patients relative to others. However, among warfarin users, Medicaid patients spent less time in therapeutic range compared with those with other forms of insurance.