Incidence and patterns of atrial fibrillation after catheter ablation of typical atrial flutter-the FLUTFIB study.

AIMS: In patients with atrial flutter (AFL), ablation of the cavotricuspid isthmus (CTI) is a highly effective procedure to prevent AFL recurrence, but atrial fibrillation (AF) may occur during follow-up. The presented FLUTFIB study was designed to identify the exact incidence, duration, timely occurrence, and associated symptoms of AF after CTI ablation using continuous cardiac monitoring via implantable loop recorders. METHODS AND RESULTS: One hundred patients with AFL without prior AF diagnosis were included after CTI ablation (mean age 69.7 ± 9.7 years, 18% female) and received an implantable loop recorder for AF detection. After a median follow-up of 24 months 77 patients (77%) were diagnosed with AF episodes. Median time to first AF occurrence was 180 (43-298) days. Episodes lasted longer than 1 h in most patients (45/77, 58%). Forty patients (52%) had AF-associated symptoms.Patients with and without AF development showed similar baseline characteristics and neither HATCH- nor CHA2DS2-VASc scores were predictive of future AF episodes. Oral anticoagulation (OAC) was stopped during FU in 32 patients (32%) and was re-initiated after AF detection in 15 patients (15%). No strokes or transient ischaemic attack episodes were observed during follow-up. CONCLUSION: This study represents the largest investigation using implantable loop recorders (ILRs) to detect AF after AFL ablation and shows a high incidence of AF episodes, most of them being asymptomatic and lasting longer than 1 h. In anticipation of trials determining the duration of AF episodes that should trigger OAC initiation, these results will help to guide anticoagulation management after CTI ablation.

Association of sleep duration with atrial fibrillation/flutter mortality in the United States: a cross-sectional analysis.

BACKGROUND: The association between sleep duration and atrial fibrillation risk is poorly understood, with inconsistent findings reported by several studies. We sought to assess the association between long sleep duration and mortality due to atrial fibrillation/atrial flutter (AF/AFL). METHODS: The 2016-2020 Centers for Disease Control and Prevention (CDC) Wide-Ranging Online Data for Epidemiologic Research dataset was used to identify death records secondary to AF/AFL in the United States population. We used the 2018 Behavioral Risk Factor Surveillance System (BRFSS) dataset of sleep duration at the county level. All counties were grouped into quartiles based on the percentage of their population with long sleep duration (i.e., ≥ 7 h), Q1 being the lowest and Q4 the highest quartile. Age-adjusted mortality rates (AAMR) were calculated for each quartile. County Health Rankings for Texas were used to adjust the AAMR for comorbidities using linear regression. RESULTS: Overall, the AAMR for AF/AFL were highest in Q4 (65.9 [95% CI, 65.5-66.2] per 100,000 person-years) and lowest in Q1 (52.3 [95% CI, 52.1-52.5] per 100,000 person-years). The AAMR for AF/AFL increased stepwise from the lowest to highest quartiles of the percentage population with long sleep duration. After adjustment for the county health ranks of Texas, long sleep duration remained associated with a significantly higher AAMR (coefficient 220.6 (95% CI, 21.53-419.72, p-value = 0.03). CONCLUSIONS: Long sleep duration was associated with higher AF/AFL mortality. Increased focus on risk reduction for AF, public awareness about the importance of optimal sleep duration, and further research to elucidate a potential causal relationship between sleep duration and AF are warranted.

Localized Re-Entry Is a Frequent Mechanism of De Novo Atypical Flutter.

BACKGROUND: Limited data exist about the origins and mechanisms of atypical atrial flutter that occurs in the absence of prior ablation or surgery. OBJECTIVES: The aims of this study were to report a large cohort of patients who presented for catheter ablation of de novo atypical flutters, to identify the most common locations and mechanisms of arrhythmia, and to describe outcomes after ablation. METHODS: Demographic, electrophysiological, and outcome data were collected for patients who underwent ablation of de novo atypical flutter. RESULTS: The mechanisms of 85 atypical flutters were identified in 62 patients and localized to the left atrium (LA) in 58 and right atrium (RA) in 27. In the LA, mechanisms were classified as macro-re-entry in 29 (50%) and localized re-entry in 29 (50%), whereas in the RA, mechanisms were macro-re-entry in 8 (30%) and localized re-entry in 19 (70%) (proportion of localized re-entry in the LA vs. RA, P = 0.08). Nine patients had both localized and macro-re-entrant atypical flutters. In the LA, localized re-entry was commonly found in the anterior LA, followed by the pulmonary veins and septum. In the RA, localized re-entry was found at various sites, including the lateral or posterior RA, septum, and coronary sinus ostium. During 39.4 months (Q1-Q3: 18.2-65.8 months) of follow-up, atrial arrhythmias occurred in 66% of patients after a single ablation and in 50% after >1 ablation. Among patients who underwent repeat ablation, compared with the index arrhythmia, different tachycardia circuits or arrhythmias were documented in 13 of 18 cases (72%). CONCLUSIONS: Atypical atrial flutters in patients without prior surgery or complex ablation are often due to localized re-entry (approximately 50% in the LA and a higher frequency in the RA). Other atrial tachycardias commonly occur during long-term follow-up following ablation, suggesting progressive atrial myopathy in these patients.

Clinical Outcomes of Decompensated Heart Failure With Reduced Ejection Fraction Admissions With or Without Atrial Fibrillation and Atrial Flutter.

The aim of our retrospective study is to determine the influence of co-morbid atrial fibrillation or flutter (AF) on decompensated congestive heart failure (CHF) admissions using data from the 2020 nationwide inpatient sample. We identified 76,835 adults admitted nonelectively with decompensated CHF. After multivariate adjustment, we found decompensated heart failure with reduced ejection fraction (HFrEF) admissions with AF had 37% higher odds of in-hospital mortality, (OR 1.38 [95% CI 1.1-1.72] P < 0.01), 33% higher odds for mechanical ventilation (MV) (OR 1.33 [95% CI 1.14-1.55] P < 0.01), 39% higher odds of early MV (OR 1.39 [95% CI 1.16-1.66] P < 0.01), 54% higher odds of cardiogenic shock (OR 1.54 [95% CI 1.29-1.84] P < 0.01), 61% increased odds of mechanical circulatory support (MCS) requirement (OR 1.61 [95% CI 1.12-2.31] P < 0.02), significantly higher odds of acute renal failure (AKI) necessitating dialysis (OR 2.20 [95% CI 1.39-2.48] P < 0.01), 1-day increase in mean length of stay (LOS) (6.7 vs 5.7 days, adjusted difference: 0.99, P < 0.01), $13,281 increase in total hospitalization charges ($84,316 vs $74,279, adjusted difference: $13,281, P < 0.05) compared to the non-AF cohort. Moreover, we found decompensated heart failure with preserved ejection fraction (HFpEF) admissions with AF had a 23% increased odds of MV (OR 1.23 [95% CI 1.01-1.50] P < 0.01), 24% higher odds of early MV (OR 1.24 [95% CI 1.00-1.53] P < 0.01), 0.36 days increase in mean LOS (5.5 vs 5.2 days, adjusted difference: 0.36, P = < 0.01), but no significant difference in in-hospital mortality (OR 1.23 [95% CI 0.86-1.75] P = 0.25), cardiogenic shock (OR 1.75 [95% CI 0.96-3.19] P < 0.07), dialysis-dependent AKI (OR 0.46 [95% CI 0.18-1.17] P < 0.10), or mean total hospitalization charges ($52,086 vs $47,990, adjusted difference: $5584, P = 0.06) compared to the non-AF cohort.

Clinical characteristics and outcomes of atrial flutter in neonates.

BACKGROUND: Atrial flutter is an uncommon arrhythmia that can cause severe morbidity, including heart failure and even death in refractory cases. This study investigated the clinical characteristics, treatment, and long-term outcomes of patients with neonatal atrial flutter and its association with heart failure. METHODS: We retrospectively reviewed atrial flutter cases observed in our center between 1999 and 2021 and analyzed the clinical characteristics, treatment, and recurrence according to the presence of heart failure. RESULTS: The study comprised 15 patients with atrial flutter, with median bodyweight and gestational age of 2.7 kg, 37+4 weeks, respectively. Twelve patients were diagnosed with atrial flutter on the first day of life. The median atrial and ventricular rates were 440/min, 220/min, respectively. Four patients exhibited congestive heart failure. Episodic recurrence was noted in five patients and occurred at a higher rate in patients with congestive heart failure (p = 0.004). Antiarrhythmic drugs for maintenance treatment were administered more often in patients with heart failure (p = 0.011). Initial treatment included direct current cardioversion (n = 9), digoxin (n = 4), and observation (n = 2). Four patients treated with cardioversion experienced recurrence during the neonatal period, and none of those treated with digoxin experienced recurrence. The median follow-up duration was 7 years, during which no atrial flutter recurrence was evident. CONCLUSION: Neonates with congestive heart failure had a higher recurrence of atrial flutter. Direct current cardioversion is the most reliable treatment for neonatal atrial flutter, whereas digoxin may be a viable treatment option in refractory and recurrent cases.

Global Burden of Atrial Fibrillation and Flutter by National Income: Results From the Global Burden of Disease 2019 Database.

Background Atrial fibrillation (AF) and atrial flutter (AFL) are common conditions that can lead to significant morbidity and death. We aimed to understand the distribution and disparities of the global burden of AF/AFL as well as the underlying risk factors. Methods and Results Data on the AF/AFL burden from the Global Burden of Disease data set were analyzed for the years 1990 to 2019, with countries grouped into low, lower-middle, upper-middle, and high national income classes according to World Bank categories. Data were supplemented with World Health Organization and World Bank information. The prevalence of AF/AFL has more than doubled (+120.7%) since 1990 in all income groups, though with a larger increment in middle-income countries (+146.6% in lower-middle- and +145.2% in upper-middle-income countries). In absolute numbers, 63.4% of AF/AFL cases originate from upper-middle-income countries, although the relative prevalence is highest in high-income countries. Prevalence of AF/AFL appears to be correlated with medical doctor rate and life expectancy. The most relevant AF/AFL risk factors are unevenly distributed among income classes, with elevated blood pressure as the only risk factor that becomes less common with increasing income. The development of these risk factors differed over time. Conclusions The global burden of AF/AFL is increasing in all income groups and is more pronounced in middle-income countries, with further growth to be expected. Underdiagnosis of AF/AFL in low- and middle-income countries may contribute to lower reported prevalence. The risk factor distribution varies between income groups.

Interatrial Block Association With Adverse Cardiovascular Outcomes in Patients Without a History of Atrial Fibrillation.

BACKGROUND: Interatrial block (IAB) is associated with thromboembolism and atrial arrhythmias. However, prior studies included small patient cohorts so it remains unclear whether IAB predicts adverse outcomes particularly in context of atrial fibrillation (AF)/atrial flutter (AFL). OBJECTIVES: This study sought to determine whether IAB portends increased stroke risk in a large cohort in the presence or absence of AFAF/AFL. METHODS: We performed a 5-center retrospective analysis of 4,837,989 electrocardiograms (ECGs) from 1,228,291 patients. IAB was defined as P-wave duration ≥120 ms in leads II, III, or aVF. Measurements were extracted as .XML files. After excluding patients with prior AF/AFL, 1,825,958 ECGs from 458,994 patients remained. Outcomes were analyzed using restricted mean survival time analysis and restricted mean time lost. RESULTS: There were 86,317 patients with IAB and 355,032 patients without IAB. IAB prevalence in the cohort was 19.6% and was most common in Black (26.1%), White (20.9%), and Hispanic (18.5%) patients and least prevalent in Native Americans (9.2%). IAB was independently associated with increased stroke probability (restricted mean time lost ratio coefficient [RMTLRC]: 1.43; 95% CI: 1.35-1.51; tau = 1,895), mortality (RMTLRC: 1.14; 95% CI: 1.07-1.21; tau = 1,924), heart failure (RMTLRC: 1.94; 95% CI: 1.83-2.04; tau = 1,921), systemic thromboembolism (RMTLRC: 1.62; 95% CI: 1.53-1.71; tau = 1,897), and incident AF/AFL (RMTLRC: 1.16; 95% CI: 1.10-1.22; tau = 1,888). IAB was not associated with stroke in patients with pre-existing AF/AFL. CONCLUSIONS: IAB is independently associated with stroke in patients with no history of AF/AFL even after adjustment for incident AF/AFL and CHA2DS2-VASc score. Patients are at increased risk of stroke even when AF/AFL is not identified.

Right atrial dysfunction is associated with atrial arrhythmias in adults with repaired tetralogy of fallot.

BACKGROUND: Adults with repaired tetralogy of Fallot (TOF) have right atrial (RA) remodeling and dysfunction, and RA function can be measured using speckle tracking echocardiography. There are limited data about the role of RA strain imaging for risk stratification in this population. We hypothesized that RA reservoir strain can identify TOF patients at risk of developing atrial arrhythmia. To test this hypothesis, we assessed the relationship between RA reservoir strain and atrial arrhythmias in adults with repaired TOF. METHOD: Retrospective cohort study of adults with repaired TOF, and no prior history of atrial arrhythmias. Atrial arrhythmia was defined as atrial fibrillation, atrial flutter/atrial tachycardia, and categorized as new-onset versus recurrent atrial arrhythmias. RESULTS: We identified 426 patients (age 33 ± 12 years; males 208 (49%)) that met the inclusion criteria. The mean RA reservoir strain, conduit strain, and booster strain were 34 ± 11%, 20 ± 9%, and 15 ± 12%, respectively. Of 426 patients, 73 (17%) developed new-onset atrial arrhythmias (atrial flutter/tachycardia n = 42; atrial fibrillation n = 31); annual incidence 1.9%. RA reservoir strain was associated with new-onset atrial arrhythmias (adjusted HR 0.95, 95% CI 0.93-0.97) after multivariable adjustment. Of 73 patients with new-onset atrial arrhythmia, 41 (56%) had recurrent atrial arrhythmia (atrial flutter/tachycardia n = 18; atrial fibrillation n = 23); annual incidence 11.2%. Similarly, RA reservoir strain was associated with recurrent atrial arrhythmias (adjusted HR 0.92, 95% CI 0.88-0.96) after multivariable adjustment. CONCLUSIONS: RA strain indices can identify patients at risk for atrial arrhythmias, and this can in turn, be used to guide the type/intensity of therapy in such patients.

Effect of dronedarone vs. placebo on atrial fibrillation progression: a post hoc analysis from ATHENA trial.

AIMS: This post hoc analysis of the ATHENA trial (NCT00174785) assessed the effect of dronedarone on the estimated burden of atrial fibrillation (AF)/atrial flutter (AFL) progression to presumed permanent AF/AFL, and regression to sinus rhythm (SR), compared with placebo. METHODS AND RESULTS: The burden of AF/AFL was estimated by a modified Rosendaal method using available electrocardiograms (ECG). Cumulative incidence of permanent AF/AFL (defined as ≥6 months of AF/AFL until end of study) or permanent SR (defined as ≥6 months of SR until end of study) were calculated using Kaplan-Meier estimates. A log-rank test was used to assess statistical significance. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were estimated using a Cox model, adjusted for treatment group. Of the 4439 patients included in this analysis, 2208 received dronedarone, and 2231 placebo. Baseline and clinical characteristics were well balanced between groups. Overall, 304 (13.8%) dronedarone-treated patients progressed to permanent AF/AFL compared with 455 (20.4%) treated with placebo (P < 0.0001). Compared with those receiving placebo, patients receiving dronedarone had a lower cumulative incidence of permanent AF/AFL (log-rank P < 0.001; HR: 0.65; 95% CI: 0.56-0.75), a higher cumulative incidence of permanent SR (log-rank P < 0.001; HR: 1.19; 95% CI: 1.09-1.29), and a lower estimated AF/AFL burden over time (P < 0.01 from Day 14 to Month 21). CONCLUSION: These results suggest that dronedarone could be a useful antiarrhythmic drug for early rhythm control due to less AF/AFL progression and more regression to SR vs. placebo, potentially reflecting reverse remodeling. CLINICAL TRIAL REGISTRATION: NCT00174785.

Right atrial tachycardia after atrial fibrillation ablation: prevalence, clinical characteristics, electrophysiological mechanisms, and long-term outcomes.

BACKGROUND: This study aims to evaluate the prevalence, clinical characteristics, electrophysiological mechanisms, and long-term outcomes of right atrial tachycardia (AT) in patients who underwent ablation for atrial fibrillation (AF). METHODS: From March 2010 to December 2020, 220 consecutive patients undergoing index AF ablation were referred for post-ablation AT recurrence. Thirty-five patients (35/220, 15.9%) with right AT recurrence (25 men; mean age 59.3 ± 10.2 years) were enrolled. These patients were divided into groups with right ATs exclusively (group 1) and right combined with left ATs (group 2). RESULTS: Fifty-three ATs were mapped in all patients, with thirty-nine ATs originating from the right atrium. The detailed distribution of all right ATs was 22 in the cavo-tricuspid isthmus (CTI), 6 in the ostium of superior vein cava (SVC), 4 in the right free wall, 4 in the right anterior atrial septum, 2 in coronary sinus ostium, and 1 in crista terminalis. Group 2 had a significantly higher incidence of typical atrial flutter (AFL) than group 1 (11/12, 90.9% vs. 12/24, 50.0%, P = 0.03). During the mean follow-up of 43.6 ± 25.2 months after the index AT ablation, the recurrence rate of AT/AF was 22.9% (8/35), and it was lower in group 1 than in group 2 (8.3% vs. 54.5%, P = 0.01). CONCLUSION: Right AT is relatively less common post-AF ablation. The CTI-dependent AFL and the ostium of SVC-derived focal AT constituted the major components of right ATs, suggesting the importance of ablation- and anatomy-related arrhythmogenic effects in the right atrium.

Global burden of atrial fibrillation/atrial flutter and its attributable risk factors from 1990 to 2019.

AIMS: The aim of this study was to estimate the global burden of atrial fibrillation (AF)/atrial flutter (AFL) and its attributable risk factors from 1990 to 2019. METHODS AND RESULTS: The data on AF/AFL were retrieved from the Global Burden of Disease Study (GBD) 2019. Incidence, disability-adjusted life years (DALYs), and deaths were metrics used to measure AF/AFL burden. The population attributable fractions (PAFs) were used to calculate the percentage contributions of major potential risk factors to age-standardized AF/AFL death. The analysis was performed between 1990 and 2019. Globally, in 2019, there were 4.7 million [95% uncertainty interval (UI): 3.6 to 6.0] incident cases, 8.4 million (95% UI: 6.7 to 10.5) DALYs cases, and 0.32 million (95% UI: 0.27 to 0.36) deaths of AF/AFL. The burden of AF/AFL in 2019 and their temporal trends from 1990 to 2019 varied widely due to gender, Socio-Demographic Index (SDI) quintile, and geographical location. Among all potential risk factors, age-standardized AF/AFL death worldwide in 2019 were primarily attributable to high systolic blood pressure [34.0% (95% UI: 27.3 to 41.0)], followed by high body mass index [20.2% (95% UI: 11.2 to 31.2)], alcohol use [7.4% (95% UI: 5.8 to 9.0)], smoking [4.3% (95% UI: 2.9 to 5.9)], diet high in sodium [4.2% (95% UI: 0.8 to 10.5)], and lead exposure [2.3% (95% UI: 1.3 to 3.4)]. CONCLUSION: Our study showed that AF/AFL is still a major public health concern. Despite the advancements in the prevention and treatment of AF/AFL, especially in regions in the relatively SDI quintile, the burden of AF/AFL in regions in lower SDI quintile is increasing. Since AF/AFL is largely preventable and treatable, there is an urgent need to implement more cost-effective strategies and interventions to address modifiable risk factors, especially in regions with high or increased AF/AFL burden.

Longitudinal risk of death, hospitalizations for atrial fibrillation, and cardiovascular events following catheter ablation of atrial fibrillation: a cohort study.

AIMS: Population studies reporting contemporary long-term outcomes following catheter ablation of atrial fibrillation (AF) are sparse.We evaluated long-term clinical outcomes following AF ablation and examined variation in outcomes by age, sex, and the presence of heart failure. METHODS AND RESULTS: We identified 30 601 unique patients (mean age 62.7 ± 11.8 years, 30.0% female) undergoing AF ablation from 2008 to 2017 in Australia and New Zealand using nationwide hospitalization data. The primary outcomes were all-cause mortality and rehospitalizations for AF or flutter, repeat AF ablation, and cardioversion. Secondary outcomes were rehospitalizations for other cardiovascular events. During 124 858.7 person-years of follow-up, 1900 patients died (incidence rate 1.5/100 person-years) with a survival probability of 93.0% (95% confidence interval (CI) 92.6-93.4%) by 5 years and 84.0% (95% CI 82.4-85.5%) by 10 years. Rehospitalizations for AF or flutter (13.3/100 person-years), repeat ablation (5.9/100 person-years), and cardioversion (4.5/100 person-years) were common, with respective cumulative incidence of 49.4% (95% CI 48.4-50.4%), 28.1% (95% CI 27.2-29.0%), and 24.4% (95% CI 21.5-27.5%) at 10 years post-ablation. Rehospitalizations for stroke (0.7/100 person-years), heart failure (1.1/100 person-years), acute myocardial infarction (0.4/100 person-years), syncope (0.6/100 person-years), other arrhythmias (2.5/100 person-years), and new cardiac device implantation (2.0/100 person-years) occurred less frequently. Elderly patients and those with comorbid heart failure had worse survival but were less likely to undergo repeat ablation, while long-term outcomes were comparable between the sexes. CONCLUSION: Patients undergoing AF ablations had good long-term survival, a low incidence of rehospitalizations for stroke or heart failure, and about half remained free of rehospitalizations for AF or flutter, including for repeat AF ablation, or cardioversion.

Association between sodium-glucose cotransporter-2 inhibitors and incident atrial fibrillation/atrial flutter in heart failure patients with reduced ejection fraction: a meta-analysis of randomized controlled trials.

Atrial fibrillation (AF) and atrial flutter (AFL) are associated with adverse outcomes in patients with heart failure and reduced ejection fraction (HFrEF). We investigated the effects of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on the incidence of AF and/or AFL in HFrEF patients. PubMed and ClinicalTrials.gov were systematically searched until March 2022 for randomized controlled trials (RCTs) that enrolled patients with HFrEF. A total of six RCTs with 9467 patients were included (N = 4731 in the SGLT2i arms; N = 4736 in the placebo arms). Compared to placebo, SGLT2i treatment was associated with a significant reduction in the risk of AF [relative risk (RR) 0.62, 95% confidence interval CI 0.44-0.86; P = 0.005] and AF/AFL (RR 0.64, 95% CI 0.47-0.87; P = 0.004). Subgroup analysis showed that empagliflozin use resulted in a significant reduction in the risk of AF (RR 0.55, 95% CI 0.34-0.89; P = 0.01) and AF/AFL (RR 0.50, 95% CI 0.32-0.77; P = 0.002). By contrast, dapagliflozin use was not associated with a significant reduction in the risk of AF (RR 0.69, 95% CI 0.43-1.11; P = 0.12) or AF/AFL (RR 0.82, 95% CI 0.53-1.27; P = 0.38). Additionally, a "shorter" duration (< 1.5 years) of treatment with SGLT2i remained associated with a reduction in the risk of AF (< 1.5 years; RR 0.58, 95% CI 0.36-0.91; P = 0.02) and AF/AFL (< 1.5 years; RR 0.52, 95% CI 0.34-0.80; P = 0.003). In conclusion, SGLT2i therapy was associated with a significant reduction in the risk of AF and AF/AFL in patients with HFrEF. These results reinforce the value of using SGLT2i in this setting.

Data standards for atrial fibrillation/flutter and catheter ablation: the European Unified Registries for Heart Care Evaluation and Randomized Trials (EuroHeart).

AIMS: Standardized data definitions are essential for monitoring and assessment of care and outcomes in observational studies and randomized controlled trials (RCTs). The European Unified Registries for Heart Care Evaluation and Randomized Trials (EuroHeart) project of the European Society of Cardiology aimed to develop contemporary data standards for atrial fibrillation/flutter (AF/AFL) and catheter ablation. METHODS AND RESULTS: We used the EuroHeart methodology for the development of data standards and formed a Working Group comprising 23 experts in AF/AFL and catheter ablation registries, as well as representatives from the European Heart Rhythm Association and EuroHeart. We conducted a systematic literature review of AF/AFL and catheter ablation registries and data standard documents to generate candidate variables. We used a modified Delphi method to reach a consensus on a final variable set. For each variable, the Working Group developed permissible values and definitions, and agreed as to whether the variable was mandatory (Level 1) or additional (Level 2). In total, 70 Level 1 and 92 Level 2 variables were selected and reviewed by a wider Reference Group of 42 experts from 24 countries. The Level 1 variables were implemented into the EuroHeart IT platform as the basis for continuous registration of individual patient data. CONCLUSION: By means of a structured process and working with international stakeholders, harmonized data standards for AF/AFL and catheter ablation for AF/AFL were developed. In the context of the EuroHeart project, this will facilitate country-level quality of care improvement, international observational research, registry-based RCTs, and post-marketing surveillance of devices and pharmacotherapies.

Atrial flutter and fibrillation in patients with pulmonary arterial hypertension or chronic thromboembolic pulmonary hypertension in the ASPIRE registry: Comparison of rate versus rhythm control approaches.

BACKGROUND: The development of atrial flutter and fibrillation (AFL/AF) in patients with pre-capillary pulmonary hypertension has been associated with an increased risk of morbidity and mortality. Rate and rhythm control strategies have not been directly compared. METHODS: Eighty-four patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) with new-onset AFL/AF were identified in the ASPIRE registry. First, baseline characteristics and rates of sinus rhythm (SR) restoration of 3 arrhythmia management strategies (rate control, medical rhythm control and DC cardioversion, DCCV) in an early (2009-13) and later (2014-19) cohort were compared. Longer-term outcomes in patients who achieved SR versus those who did not were then explored. RESULTS: Sixty (71%) patients had AFL and 24 (29%) AF. Eighteen (22%) patients underwent rate control, 22 (26%) medical rhythm control and 44 (52%) DCCV. SR was restored in 33% treated by rate control, 59% medical rhythm control and 95% DCCV (p < 0.001). Restoration of SR was associated with greater improvement in functional class (FC) and Incremental Shuttle Walk Distance (p both <0.05). It also independently predicted superior survival (3-year survival 62% vs 23% in those remaining in AFL/AF, p < 0.0001). In addition, FC III/IV independently predicted higher mortality (HR 2.86, p = 0.007). Right atrial area independently predicted AFL/AF recurrence (OR 1.08, p = 0.01). DCCV was generally well tolerated with no immediate major complications. CONCLUSIONS: Restoration of SR is associated with superior functional improvement and survival in PAH/CTEPH compared with rate control. DCCV is generally safe and is more effective than medical therapy at achieving SR.

Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter.

OBJECTIVE: We aimed to compare cryoballoon pulmonary vein isolation (PVI) with standard radiofrequency cavotricuspid isthmus (CTI) ablation as first-line treatment for typical atrial flutter (AFL). METHODS: Cryoballoon Pulmonary Vein Isolation as First-Line Treatment for Typical Atrial Flutter was an international, multicentre, open with blinded assessment trial. Patients with CTI-dependent AFL and no documented atrial fibrillation (AF) were randomised to either cryoballoon PVI alone or radiofrequency CTI ablation. Primary efficacy outcome was time to first recurrence of sustained (>30 s) symptomatic atrial arrhythmia (AF/AFL/atrial tachycardia) at 12 months as assessed by continuous monitoring with an implantable loop recorder. Primary safety outcome was a composite of death, stroke, tamponade requiring drainage, atrio-oesophageal fistula, pacemaker implantation, serious vascular complications or persistent phrenic nerve palsy. RESULTS: Trial recruitment was halted at 113 of the target 130 patients because of the SARS-CoV-2 pandemic (PVI, n=59; CTI ablation, n=54). Median age was 66 (IQR 61-71) years, with 98 (86.7%) men. At 12 months, the primary outcome occurred in 11 (18.6%) patients in the PVI group and 9 (16.7%) patients in the CTI group. There was no significant difference in the primary efficacy outcome between the groups (HR 1.11, 95% CI 0.46 to 2.67). AFL recurred in six (10.2%) patients in the PVI arm and one (1.9%) patient in the CTI arm (p=0.116). Time to occurrence of AF of ≥2 min was significantly reduced with cryoballoon PVI (HR 0.46, 95% CI 0.25 to 0.85). The composite safety outcome occurred in four patients in the PVI arm and three patients in the CTI arm (p=1.000). CONCLUSION: Cryoballoon PVI as first-line treatment for AFL is equally effective compared with standard CTI ablation for preventing recurrence of atrial arrhythmia and better at preventing new-onset AF. TRIAL REGISTRATION NUMBER: NCT03401099.

Atrial flutter without structural heart disease in pediatrics: a retrospective review of cases in the Hospital Infantil Miguel Servet, Zaragoza, Spain.

BACKGROUND: Atrial flutter is a rare condition in pediatrics that usually occurs as a late complication after surgery for congenital heart diseases, although it can also appear in structurally normal hearts. CLINICAL CASES: We conducted a retrospective study of cases of atrial flutter with no structural heart disease diagnosed in a pediatric population (between 0 and 15 years of age) during 2015-2021 in a tertiary hospital. A total of seven cases were diagnosed, with a clear predominance of males (6/7). Of the seven patients, five debuted in the perinatal period: two were diagnosed at 20 and 36 hours of life, and three, prenatally. Among these perinatal cases, more than half (3/5) were preterm. The treatment was electrical cardioversion. The evolution was satisfactory in these cases, and there were no tachycardias in their subsequent development. In contrast, when the debut occurred at a later age (5-7 years), it was associated with channelopathy (Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia), and electrical ablation of the ectopic focus was required due to poor response to pharmacological treatment. CONCLUSIONS: This study confirms the low incidence of this pathology in pediatrics and the benignity and good prognosis of neonatal flutter in most cases. The prognosis worsens when atrial flutter is diagnosed in older children, and the probability of concomitant associated heart disease increases.

INTRODUCCIÓN: El flutter o aleteo auricular es una patología poco frecuente en pediatría que suele presentarse como complicación tardía tras la cirugía de cardiopatías congénitas, aunque también puede aparecer en corazones estructuralmente normales. CASOS CLÍNICOS: Se llevó a cabo un estudio retrospectivo de los casos de flutter auricular sin cardiopatía estructural diagnosticados en una población pediátrica (entre 0 y 15 años de edad) durante el periodo 2015-2021 en un hospital terciario. En total fueron diagnosticados siete casos, con un claro predominio de varones (6/7). De los siete, cinco debutaron en periodo perinatal: dos fueron diagnosticados a las 20 y 36 horas de vida y tres de ellos, prenatalmente. Entre estos casos perinatales, más de la mitad (3/5) fueron pretérmino. El tratamiento fue la cardioversión eléctrica. La evolución fue satisfactoria en estos casos, y no se presentaron taquicardias en su evolución posterior. Por el contrario, cuando el debut se produjo en edades posteriores (5-7 años), se asoció con canalopatía (síndrome de Brugada y taquicardia ventricular polimorfa catecolaminérgica) que requirió de una ablación eléctrica del foco ectópico por escasa respuesta al tratamiento farmacológico. CONCLUSIONES: En este trabajo se confirma la baja incidencia de esta patología en pediatría, además de la benignidad y el buen pronóstico de flutter neonatal en la mayoría de casos. Cuando el diagnóstico se realiza en niños mayores, el pronóstico empeora, y aumenta la probabilidad de presentar de forma concomitante cardiopatías asociadas.

Association of Intravenous Potassium and Magnesium Administration With Spontaneous Conversion of Atrial Fibrillation and Atrial Flutter in the Emergency Department.

Importance: Whether the simultaneous intravenous administration of potassium and magnesium is associated with the probability of spontaneous conversion to sinus rhythm (SCV) in the acute treatment of atrial fibrillation (AF) and atrial flutter (AFL) is unknown. Objective: To assess potassium and magnesium administration and SCV probability in AF and AFL in the emergency department. Design, Setting, and Participants: A registry-based cohort study was conducted in the Department of Emergency Medicine of the Medical University of Vienna, Austria. All consecutive patients with AF or AFL were screened between February 6, 2009, and February 16, 2020. Interventions: Intravenous administration of potassium, 24 mEq, and magnesium, 145.8 mg. Main Outcomes and Measures: The primary outcome was the probability of SCV during the patient's stay in the emergency department. Multivariable cluster-adjusted logistic regression was used to estimate the association between potassium and magnesium administration and the probability of SCV. Results: A total of 2546 episodes of nonpermanent AF (median patient age, 68 [IQR, 58-75] years, 1411 [55.4%] men) and 573 episodes of nonpermanent AFL (median patient age, 68 [IQR, 58-75] years; 332 [57.9%] men) were observed. In AF episodes, intravenous potassium and magnesium administration vs no administration was associated with increased odds of SCV (19.2% vs 10.4%; odds ratio [OR], 1.98; 95% CI, 1.53-2.57). In AFL episodes, in contrast, no association was noted for the probability of SCV with potassium and magnesium vs no administration (13.0% vs 12.5%; OR, 1.05; 95% CI, 0.65-1.69). Conclusions and Relevance: The findings of this registry-based cohort study on intravenous administration of potassium and magnesium suggest an increased probability of SCV in nonpermanent AF, but not AFL, during a patients' stay in the emergency department.

Effect of specialist consultation on emergency department revisits among patients with uncomplicated recent-onset atrial fibrillation or flutter.

OBJECTIVES: To examine the association between specialist consultation and risk of 30-day ED revisit in emergency department (ED) patients with recent-onset uncomplicated atrial fibrillation or flutter (AF/AFL). METHODS: As a secondary analysis of a previously published trial, clinical experts identified predictors of consultation including age and sex, ED sinus conversion, thromboembolic risk, heart rate, rate control medication use, coronary artery disease and anti-platelet use, and chronic obstructive pulmonary disease. These were included in a propensity-matched hierarchical Bayesian model accounting for hospital site as a random effect, with 30-day ED revisit as the primary outcome. We also measured ED length of stay for consulted and non-consulted patients. RESULTS: We analyzed data from 11 sites for 829 ED patients with AF/AFL, of whom 364 (44%) had specialist consultation. A total of 128 patients (15.4%) had an ED revisit, 78 (16.8%) from the no consult group and 50 (13.7%) from the consult group. Consultation rates ranged from 8.8 to 71% between sites. Median length of stay was 591 min (interquartile range [IQR] 359-1024) for consulted patients and 300 min (IQR 212-409) for patients without consultation. After propensity-matching, consulted patients had a 0.6% (IQR - 4 to 3%) lower risk of 30-day revisits than non-consulted patients (probability of lower risk 55%). CONCLUSIONS: In ED patients with uncomplicated AF/AFL, there was substantial between-site variation in specialist consultations; such consultation was unlikely to influence revisits within 30 days while ED length of stay was nearly double. ED specialist consultations may not be necessary for uncomplicated patients.

RéSUMé: OBJECTIFS: Examiner l'association entre la consultation d'un spécialiste et le risque d'une nouvelle visite aux urgences à 30 jours chez les patients des urgences souffrant de fibrillation auriculaire ou de flutter non compliqué d'apparition récente (FA/AFL). MéTHODES: Dans le cadre d'une analyse secondaire d'un essai précédemment publié, des experts cliniques ont identifié les facteurs prédictifs de la consultation, notamment l'âge et le sexe, la conversion sinusale des urgences, le risque thromboembolique, la fréquence cardiaque, l'utilisation de médicaments pour contrôler la fréquence cardiaque, la maladie coronarienne et l'utilisation d'antiplaquettaires, et la maladie pulmonaire obstructive chronique. Ceux-ci ont été inclus dans un modèle bayésien hiérarchique apparié en fonction de la propension, qui tient compte du site de l'hôpital comme effet aléatoire, le critère principal étant le retour aux urgences à 30 jours. Nous avons également mesuré la durée de séjour aux urgences des patients consultés et non consultés. RéSULTATS: Nous avons analysé les données de 11 sites pour 829 patients du service d'urgence atteints de FA/AFL, dont 364 (44 %) avaient consulté un spécialiste. Un total de 128 patients (15,4 %) ont eu une nouvelle visite à l'urgence, 78 (16,8 %) du groupe sans consultation et 50 (13,7 %) du groupe de consultation. Les taux de consultation variaient de 8,8 % à 71 % selon les sites. La durée médiane du séjour était de 591 minutes (intervalle interquartile [IQR] 359-1024) pour les patients consultés et de 300 min (IQR 212-409) pour les patients sans consultation. Après appariement par propension, les patients consultés avaient un risque inférieur de 0,6 % (IQR -4 % à 3 %) de revisites à 30 jours par rapport aux patients non consultés (probabilité de risque inférieur de 55 %). CONCLUSIONS: Chez les patients des urgences atteints de FA/AFL non compliquée, il y avait une variation substantielle entre les sites dans les consultations de spécialistes ; il était peu probable qu'une telle consultation influence les visites dans les 30 jours alors que la durée du séjour aux urgences était presque le double. Les consultations de spécialistes des urgences peuvent ne pas être nécessaires pour les patients sans complication.