Gender Differences With Ibutilide Effectiveness and Safety in Cardioversion of Atrial Fibrillation.

INTRODUCTION: Few studies have examined the use of ibutilide in noncardiac surgical populations. Our study considered the effectiveness and safety of ibutilide in cardioversion of atrial fibrillation (AF) in medical and surgical intensive care patients. METHODS: A retrospective chart review was performed for patients with a confirmed diagnosis of AF who were hemodynamically stable and received ibutilide after the initial diagnosis. Patients were administered 1 mg of ibutilide fumarate intravenous for 10 min with a second dose administered if AF persisted after 30 min. Patients were pretreated with intravenous magnesium sulfate if their blood magnesium level was <2 mg/dL. RESULTS: Fifty seven total female patients and 99 male patients received ibutilide. Females had an 88% conversion rate to normal sinus rhythm (NSR) compared to 68% in males (P = 0.008). A 70% successful return to NSR was observed in patients from all groups pretreated with magnesium sulfate (P = 0.045). One year after discharge, 74% of the patients stayed in the NSR. CONCLUSIONS: Within our population, pretreatment with magnesium sulfate followed by ibutilide was associated with increased conversion to NSR. Additionally, we noted that females had a higher conversion rate to NSR compared to males, regardless of whether they were pretreated with magnesium sulfate.

Medical cardioversion of atrial fibrillation and flutter with class IC antiarrhythmic drugs in young patients with and without congenital heart disease.

INTRODUCTION: The use of flecainide and propafenone for medical cardioversion of atrial fibrillation (AF) and atrial flutter/intra-atrial reentrant tachycardia (IART) is well-described in adults without congenital heart disease (CHD). Data are sparse regarding their use for the same purpose in adults with CHD and in adolescent patients with anatomically normal hearts and we sought to describe the use of class IC drugs in this population and identify factors associated with decreased likelihood of success. METHODS: Single center retrospective cohort study of patients who received oral flecainide or propafenone for medical cardioversion of AF or IART from 2000 to 2022. The unit of analysis was each episode of AF/IART. We performed a time-to-sinus rhythm analysis using a Cox proportional hazards model clustering on the patient to identify factors associated with increased likelihood of success. RESULTS: We identified 45 episodes involving 41 patients. As only episodes of AF were successfully cardioverted with medical therapy, episodes of IART were excluded from our analyses. Use of flecainide was the only factor associated with increased likelihood of success. There was a statistically insignificant trend toward decreased likelihood of success in patients with CHD. CONCLUSIONS: Flecainide was more effective than propafenone. We did not detect a difference in rate of conversion to sinus rhythm between patients with and without CHD and were likely underpowered to do so, however, there was a trend toward decreased likelihood of success in patients with CHD. That said, medical therapy was effective in >50% of patients with CHD with AF.

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.

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.

Treatment, not delivery, of the late preterm and term fetus with supraventricular arrhythmia.

OBJECTIVE: While in-utero treatment of sustained fetal supraventricular arrhythmia (SVA) is standard practice in the previable and preterm fetus, data are limited on best practice for late preterm (34 + 0 to 36 + 6 weeks), early term (37 + 0 to 38 + 6 weeks) and term (> 39 weeks) fetuses with SVA. We reviewed the delivery and postnatal outcomes of fetuses at ≥ 35 weeks of gestation undergoing treatment rather than immediate delivery. METHODS: This was a retrospective case series of fetuses presenting at ≥ 35 weeks of gestation with sustained SVA and treated transplacentally at six institutions between 2012 and 2022. Data were collected on gestational age at presentation and delivery, SVA diagnosis (short ventriculoatrial (VA) tachycardia, long VA tachycardia or atrial flutter), type of antiarrhythmic medication used, interval between treatment and conversion to sinus rhythm and postnatal SVA recurrence. RESULTS: Overall, 37 fetuses presented at a median gestational age of 35.7 (range, 35.0-39.7) weeks with short VA tachycardia (n = 20), long VA tachycardia (n = 7) or atrial flutter (n = 10). Four (11%) fetuses were hydropic. In-utero treatment led to restoration of sinus rhythm in 35 (95%) fetuses at a median of 2 (range, 1-17) days; this included three of the four fetuses with hydrops. Antiarrhythmic medications included flecainide (n = 11), digoxin (n = 7), sotalol (n = 11) and dual therapy (n = 8). Neonates were liveborn at 36-41 weeks via spontaneous vaginal delivery (23/37 (62%)) or Cesarean delivery (14/37 (38%)). Cesarean delivery was indicated for fetal SVA in two fetuses, atrial ectopy or sinus bradycardia in three fetuses and obstetric reasons in nine fetuses that were in sinus rhythm at the time of delivery. Twenty-one (57%) cases were treated for recurrent SVA after birth. CONCLUSION: In-utero treatment of the near term and term (≥ 35-week) SVA fetus is highly successful even in the presence of hydrops, with the majority of cases delivered vaginally closer to term, thereby avoiding unnecessary Cesarean section. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Impact of intravenous calcium with diltiazem for atrial fibrillation/flutter in the emergency department.

OBJECTIVE: The purpose of this study was to evaluate the effect of early intravenous (IV) calcium on systolic blood pressure (SBP) when administered with IV diltiazem in subjects with atrial fibrillation (AF) or flutter (AFL) with rapid ventricular response (RVR) in the Emergency Department (ED). METHODS: This was a multicenter, retrospective cohort study that evaluated adults admitted to the ED with documented AF or AFL, heart rate (HR) > 120 bpm, SBP 90 to 140 mmHg, and received treatment with IV diltiazem for rate control. The primary outcome was the change in SBP 60 min (+/- 30 min) after initial IV diltiazem administration. Secondary outcomes included time to initial rate control (HR < 100 bpm), time to sustained rate control (HR < 100 bpm for 3 h), change in HR, rates of hypotension, bradycardia, hypercalcemia, and line extravasation within 24 h of initial diltiazem administration. RESULTS: There were 198 subjects in the diltiazem monotherapy group and 56 subjects in the diltiazem with calcium group meeting the inclusion criteria. The primary outcome, median change in SBP 60 min after initial IV diltiazem administration, was similar between groups (-2 mmHg vs -1.5 mmHg; p = 0.642), but this difference was not statistically significant. All secondary outcomes were found to be similar between groups. Although not statistically significant, hypotension occurred more often in the diltiazem with calcium group (20.2% vs 32.1%; p = 0.060) while bradycardia occurred more often in the diltiazem monotherapy group (4.5% vs 0%; p = 0.213). In terms of achieving rate control, the administration of calcium with diltiazem did not significantly change the time to initial rate control (1.4 h vs 1.8 h; p = 0.141) or time to sustained rate control (7.9 h vs 7.7 h; p = 0.570) compared to diltiazem alone. CONCLUSIONS: In the setting of AF/AFL with RVR, administration of IV calcium with IV diltiazem did not show a significant impact on clinical or safety outcomes compared to IV diltiazem monotherapy.

What Is the Optimal Digoxin Level? Challenging Case of Fetal Atrial Flutter Treatment in a Monochorionic Diamniotic Twin.

Background: Atrial flutter is an infrequent yet potentially fatal arrhythmia. Digoxin is the preferred first-line treatment for fetal atrial flutter due to its efficacy and favorable safety profile. The optimal digoxin serum target level for neonatal atrial flutter management remains uncertain, with the standard target level ranging from 1.0 to 2.0 ng/mL due to potential toxicity concerns above this threshold. Case Presentation: We present a case of atrial flutter in a fetus within a monochorionic diamniotic (MCDA) twin pregnancy that was successfully managed using a higher-than-standard target level of digoxin. A 34-year-old nulliparous woman was referred to our institution at 31 + 3 weeks of gestation due to fetal distress in an MCDA twin pregnancy. Fetal echocardiography revealed a ventricular rate of 214 bpm in twin A, while twin B exhibited no abnormal findings. Conclusions: Our case highlights a distinct correlation between the serum digoxin level and its impact on atrial flutter. A higher target serum level of digoxin may be necessary to achieve sinus conversion due to the unique maternal and fetal circulatory characteristics in MCDA pregnancies.

Early initiation of anti-relapse antiarrhythmic therapy in patients with atrial fibrillation and flutter after pharmacological cardioversion with refralon.

Aim      Evaluating the efficacy and safety of early administration of antirecurrence antiarrhythmic therapy (AAT) following restoration of sinus rhythm (SR) with refralon.Aim      Evaluating the efficacy and safety of early administration of antirecurrence antiarrhythmic therapy (AAT) following restoration of sinus rhythm (SR) with refralon.Material and methods  The study included 247 patients with atrial fibrillation/atrial flutter (AF/AFL) (142 men) who underwent pharmacological cardioversion (PCV) with refralon. A 4-step schedule of drug administration was used (successive intravenous infusions at doses of 5, 5, 10, and 10 µg/kg; maximum total dose was 30 µg/kg). Patients who recovered SR and had no contraindications were prescribed antirecurrence AAT in the early (≤24 h; n=101) or delayed (≥24 h; n=95) period. Lappaconitine hydrobromide, propafenone, and sotalol were administered orally as the antirecurrence therapy. The decision on the time of initiating ATT and the choice of the drug and its dose was taken by the attending physician individually. The safety criteria included a prolonged PQ interval >200 ms; second- or third-degree atrioventricular block; QRS complex duration >120 ms; QT prolongation >500 ms; and heartbeat pauses >3 s. The efficacy criteria included the absence of sustained recurrence of AF/AFL after initiation of AAT and the duration of hospitalization after PCV. Patients were followed up during the study until they were discharged from the hospital.Results SR was recovered in 229 (92.7 %) patients. In the group of early AAT initiation, a PQ duration >200 ms was observed in 8 (7.9 %) patients, whereas in the group of delayed AAT initiation, in 7 patients (7.4 %; p=1.000). A wide QRS complex >120 ms was recorded in 1 (1.1 %) patient of the delayed AAT initiation group and in none of the patients of the early AAT initiation group (p=0.485). Ventricular arrhythmogenic effects and QT prolongation >500 ms were not detected in any patient. Numbers of early AF recurrence did not differ in the groups of early and delayed AAT initiation: 6 (5.9 %) vs. 5 (5.3 %), respectively (p=1.000). Median duration of hospitalization after PCV was 4 days in the group of early AAT initiation and 5 days in the group of delayed AAT initiation (р=0.009).Conclusion      Early initiation of the refralon AAT does not increase the risk of drug adverse effects and reduces the duration of stay in the hospital.

Efficacy and Safety of Catheter Ablation vs Antiarrhythmic Drugs as Initial Therapy for Management of Symptomatic Paroxysmal Atrial Fibrillation: A Meta-Analysis.

BACKGROUND: Catheter ablation is an effective treatment for atrial fibrillation (AF), primarily performed in patients who fail antiarrhythmic drugs. Whether early catheter ablation, as first-line therapy, is associated with improved clinical outcomes remains unclear. METHODS: Electronic databases (PubMed, Scopus, Embase) were searched until March 28th, 2021. Randomized controlled trials (RCTs) compared catheter ablation vs antiarrhythmic drug therapy as first-line therapy were included. The primary outcome of interest was the first documented recurrence of any atrial tachyarrhythmia (symptomatic or asymptomatic; AF, atrial flutter, and atrial tachycardia). Secondary outcomes included symptomatic atrial tachyarrhythmia (AF, atrial flutter, and atrial tachycardia) and serious adverse events. Unadjusted risk ratios (RR) were calculated from dichotomous data using Mantel Haenszel (M-H) random-effects with statistical significance considered if the confidence interval (CI) excludes one and p < 0.05. RESULTS: A total of six RCTs with 1212 patients (Ablation n = 609; Antiarrhythmic n = 603) were included. Follow- up period ranged from 1-2 years. Patients who underwent ablation were less likely to experience any recurrent atrial tachyarrhythmia when compared to patients receiving antiarrhythmic drugs (RR 0.63; 95% CI 0.55-0.73; p < 0.00001). Symptomatic atrial tachyarrhythmia was also lower in the ablation arm (RR 0.53; 95% CI 0.32-0.87; p = 0.01). No statistically significant differences were noted for overall any type of adverse events (RR 0.93; 95% CI 0.68-1.27; p = 0.64) and cardiovascular adverse events (RR 0.90; 95% CI 0.56-1.44; p = 0.65) respectively. CONCLUSIONS: Catheter ablation, as first-line therapy, was associated with a significantly lower rate of tachyarrhythmia recurrence compared to conventional antiarrhythmic drugs, with a similar adverse effect risk profile. These findings support a catheter ablation strategy as first-line therapy among patients with symptomatic paroxysmal atrial fibrillation.

Canagliflozin and atrial fibrillation in type 2 diabetes mellitus: A secondary analysis from the CANVAS Program and CREDENCE trial and meta-analysis.

AIM: To assess the effects of canagliflozin on the incidence of atrial fibrillation/atrial flutter (AF/AFL) and other key cardiorenal outcomes in a pooled analysis of the CANVAS and CREDENCE trials. MATERIALS AND METHODS: Participants with type 2 diabetes and high risk of cardiovascular disease or chronic kidney disease were included and randomly assigned to canagliflozin or placebo. We explored the effects of canagliflozin on the incidence of first AF/AFL events and AF/AFL-related complications (ischaemic stroke/transient ischaemic attack/hospitalization for heart failure). Major adverse cardiovascular events and a renal-specific outcome by baseline AF/AFL status were analysed using Cox regression models. RESULTS: Overall, 354 participants experienced a first AF/AFL event. Canagliflozin had no detectable effect on AF/AFL (hazard ratio [HR] 0.82, 95% confidence interval [CI] 0.67-1.02) compared with placebo. Subgroup analysis, however, suggested a possible reduction in AF/AFL in those with no AF/AFL history (HR 0.78, 95% CI 0.62-0.99). Canagliflozin was also associated with a reduction in AF/AFL-related complications (HR 0.74, 95% CI 0.65-0.86). There was no evidence of treatment heterogeneity by baseline AF/AFL history for other key cardiorenal outcomes (all Pinteraction > 0.14). Meta-analysis of five sodium-glucose cotransporter-2 (SGLT2) inhibitor trials demonstrated a 19% reduction in AF/AFL events with active treatment (HR 0.81, 95% CI 0.72-0.92). CONCLUSIONS: Overall, a significant effect of canagliflozin on the incidence of AF/AFL events could not be shown, however, a possible reduction in AF/AFL events in those with no prior history requires further investigation. Meta-analysis suggests SGLT2 inhibition reduces AF/AFL incidence.

Comparison of Sodium-Glucose Cotransporter 2 Inhibitors and Glucagon-like Peptide Receptor Agonists for Atrial Fibrillation in Type 2 Diabetes Mellitus: Systematic Review With Network Meta-analysis of Randomized Controlled Trials.

ABSTRACT: Atrial fibrillation (AF) is a major public health concern with a rising prevalence. Although sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide-1 receptor agonists (GLP-1RAs) have shown the respective favorable effects on reducing the occurrence of AF/atrial flutter (AFL), comparative protective AF/AFL effects between above 2 novel antidiabetic agents remain unavailable. Thus, we aimed to evaluate the comparative efficacy of SGLT2is and GLP-1RAs in reducing the risk of AF/AFL in patients with type 2 diabetes and estimate relative rankings of interventions. PubMed, Embase, and ClinicalTrials.gov were searched up to December 1, 2020. All available randomized controlled trials comparing SGLT2is and GLP-1RAs with one another or placebo in patients with type 2 diabetes were included. Pooled results were shown as risk ratios (RRs) with 95% confidence intervals (CIs). We used a frequentist network meta-analysis to evaluate the outcomes of interests. Thirty-six randomized controlled trials including 85,701 participants with type 2 diabetes were identified. Compared with placebo, both SGLT2is (RR: 0.82, 95% CI, 0.68-0.99) and GLP-1RAs (RR: 0.86, 95% CI, 0.76-0.97; RR long-acting ones: 0.87, 95% CI, 0.76-0.99; RR short-acting ones: 0.72, 95% CI, 0.45-1.14) significantly reduced AF/AFL risk. No significant difference between SGLT2is and GLP-1RAs was noted (RR: 0.95, 95% CI, 0.76-1.2). Compared with placebo, results from the analysis showed an RR of 0.72 (95% CI, 0.45-1.14) for short-acting GLP-1RAs and 0.87 (95% CI, 0.76-0.99) for long-acting GLP-1RAs in reducing the risk of AF/AFL. Compared with placebo, both SGLT2is and GLP-1RAs possessed favorable effects on reducing the risk of AF/AFL. However, no difference was observed when comparisons were made between them. In addition, long-acting ones may confer a more pronounced AF/AFL reduction benefit compared with placebo.

Efficacy and safety of dronedarone across age and sex subgroups: a post hoc analysis of the ATHENA study among patients with non-permanent atrial fibrillation/flutter.

AIMS: Age and sex may impact the efficacy of antiarrhythmic drugs on cardiovascular outcomes and arrhythmia recurrences in patients with atrial fibrillation (AF). We report on a post hoc analysis of the ATHENA study (NCT00174785), which examined cardiovascular outcomes in patients with non-permanent AF treated with dronedarone vs. placebo. METHODS AND RESULTS: Efficacy and safety of dronedarone were assessed in patients according to age and sex. Baseline characteristics were comparable across subgroups, except for cardiovascular comorbidities, which were more frequent with increasing age. Dronedarone significantly reduced the risk of cardiovascular hospitalization or death due to any cause among patients 65-74 [n = 1830; hazard ratio (HR) 0.71, 95% confidence interval (CI) 0.60-0.83; P < 0.0001] and ≥75 (n = 1925; HR 0.75, 95% CI 0.65-0.88; P = 0.0002) years old and among males (n = 2459; HR 0.74, 95% CI 0.64-0.84; P < 0.00001) and females (n = 2169; HR 0.77, 95% CI 0.67-0.89; P = 0.0002); outcomes were similar for time to AF/AFL recurrence. Among patients aged <65 years (n = 873), cardiovascular hospitalization or death due to any cause with dronedarone vs. placebo was associated with an HR of 0.89 (95% CI 0.71-1.11; P = 0.3). The incidence of all treatment-emergent adverse events (TEAEs) and TEAEs leading to treatment discontinuation was comparable among males and females, and increased with increasing age. CONCLUSIONS: These results support the use of dronedarone for the improvement of clinical outcomes among patients aged ≥65 years and regardless of sex.

Characteristics of patients with atrial flutter and spontaneous 1:1 atrioventricular conduction with and without anti-arrhythmic drug treatment.

Atrial flutter (AFL) is a large reentrant circuit located in the right atrium. Anti-arrhythmic drugs (AADs) can provoke AFL with 1:1 atrioventricular conduction (AVC) to cause hemodynamic collapse. We elucidated the characteristics of patients with AFL exhibiting spontaneous 1:1 AVC. Fifteen patients (1:1 AFL group; 11 males, 52.4 ± 13.7 years old) who documented AFL with 1:1 AVC were enrolled and compared to 153 patients without 1:1 AVC (Control group; 137 males, 68.9 ± 11.2 years old). AFL cycle length during maximum AVC was significantly longer in the 1:1 AFL group than in the control group (274.7 ± 37.0 vs. 216.2 ± 25.6 ms, p < 0.001). Among 1:1 AVC group, 9 patients had AADs, and AFL cycle length was significantly longer during 1:1 AVC as compared with 2:1 AVC documented the other day (284.4 ± 41.3 vs. 233.3 ± 26.0 ms, p < 0.001), suggesting enhancement effect of the AADs during 1:1 AVC. Remaining 6 patients who did not take AADs, 2 patients showed enlargement of the tricuspid annulus and 3 patients developed 1:1 AVC during exercise. Multivariate analysis revealed that younger age and the use of AADs was independent risk factors for the development of 1:1 AFL group. Prolonged AFL cycle length associated with the class Ia/Ic AAD use, slower heart rate during sinus rhythm and younger age were important risk factors for the development of 1:1 AVC during AFL.

Direct oral anticoagulant use and risk of severe COVID-19.

BACKGROUND: Hypercoagulability and thromboembolism are prominent features of severe COVID-19, and ongoing anticoagulant use might be protective. METHODS: We conducted a nationwide register-based cohort study in Sweden, February through May, 2020, to assess whether ongoing direct oral anticoagulant (DOAC) use was associated with reduced risk of hospital admission for laboratory-confirmed COVID-19, or a composite of intensive care unit (ICU) admission or death due to laboratory-confirmed COVID-19. RESULTS: DOAC use (n = 103 703) was not associated with reduced risk of hospital admission for COVID-19 (adjusted hazard ratio [aHR] [95% confidence interval] 1.00 [0.75-1.33] vs. nonuse atrial fibrillation comparator [n = 36 875]; and aHR 0.94 [0.80-1.10] vs. nonuse cardiovascular disease comparator [n = 355 699]), or ICU admission or death due to COVID-19 (aHRs 0.76 [0.51-1.12], and 0.90 [0.71-1.15], respectively). CONCLUSION: Ongoing DOAC use was not associated with reduced risk of severe COVID-19, indicating that prognosis would not be modified by early outpatient DOAC initiation.

Mechanical thrombectomy of COVID-19 DVT with congenital heart disease leading to phlegmasia cerulea dolens: a case report.

BACKGROUND: COVID-19 and Fontan physiology have each been associated with an elevated risk of venous thromboembolism (VTE), however little is known about the risks and potential consequences of having both. CASE PRESENTATION: A 51 year old male with tricuspid atresia status post Fontan and extracardiac Glenn shunt, atrial flutter, and sinus sick syndrome presented with phlegmasia cerulea dolens (PCD) of the left lower extremity in spite of supratherapeutic INR in the context of symptomatic COVID-10 pneumonia. He was treated with single session, catheter directed mechanical thrombectomy that was well-tolerated. CONCLUSIONS: This report of acute PCD despite therapeutic anticoagulation with a Vitamin K antagonist, managed with emergent mechanical thrombectomy, calls to attention the importance of altered flow dynamics in COVID positive patients with Fontan circulation that may compound these independent risk factors for developing deep venous thrombosis with the potential for even higher morbidity.

Heart rate outcomes with concomitant parenteral calcium channel blockers and beta blockers in rapid atrial fibrillation or flutter.

BACKGROUND: Patients who present with atrial fibrillation (AF) or flutter with rapid ventricular response (RVR) and hemodynamic stability may be managed with either an intravenous (IV) nondihydropyridine calcium channel blocker (CCB) or a beta-blocker (BB). Patients without improved heart rates may need to switch to, or add, a second AV nodal blocker. OBJECTIVE: To evaluate the incidence of rate control achievement and bradycardia in patients in AF or atrial flutter with RVR who receive both an intravenous CCB and a BB. METHODS: A retrospective chart review of patients who received concomitant intravenous CCB or BB for the treatment of rapid AF or atrial flutter from April 2016 through July 2018 in the emergency department. Patients were excluded if the second agent was ordered but not administered, or if they received IV amiodarone or digoxin. RESULTS: A total of 136 patients were included in the analysis, and of those, 46% (n = 62) of patients achieved a heart rate <110 bpm without bradycardia, and 3.7% (n = 5) developed bradycardia. Age, initial heart rate, time between CCB and BB administration, addition of an oral CCB or BB administration, or administration of IV magnesium did not impact target heart rate achievement. CONCLUSION: Adding a second nodal blocker in patients who did not achieve rate control with the first agent resulted in heart rate control 46% of the time. The development of symptomatic bradycardia was uncommon.

Association of Fetal Atrial Flutter with Neonatal Atrioventricular Re-entry Tachycardia Involving Accessory Pathway: A Link to be Remembered.

To investigate prenatal and postnatal outcomes of atrial flutter and its association with the development of a second tachycardia, following restoration of sinus rhythm, in the fetus or newborn. This study is a retrospective review of all fetuses that presented with atrial flutter from January 2001 to December 2019 at the University Hospital of Wales, Cardiff, UK. The specific type of arrhythmia, its time of appearance and clinical characteristics, echocardiographic findings, medical management, and postnatal outcomes were evaluated. Sixteen fetuses were diagnosed with atrial flutter (AFL). Thirteen fetuses had persistent AFL and three fetuses had intermittent AFL. Seven patients had hydrops, of which one had Ebstein's anomaly and the other six had normal hearts. Three of the fetuses that presented with AFL were diagnosed at 20, 21, and 23 weeks' gestation and the remainder were diagnosed in the third trimester. Thirteen patients with AFL received antiarrhythmic drugs and three were delivered without any treatment. Five fetuses with AFL developed atrioventricular reciprocating tachycardia following DC cardioversion after birth, and four of them exhibited pre-excitation on the ECG. These five patients (31.3%) required postnatal antiarrhythmic treatment for up to 2 years. Pre-excitation disappeared in two patients during follow-up and two asymptomatic patients with neonatal pre-excitation required accessory pathway ablation. Fetal atrial flutter has a strong association with atrioventricular reciprocating tachycardia and ventricular pre-excitation in the neonatal period. Therefore, electrocardiograms should be carefully reviewed in newborns following the initial resolution of atrial flutter.

[The Chinese expert recommendations on the clinical use of dronedarone].

Dronedarone, a class Ⅲ antiarrhythmic drug, is a deiodinated benzofuran derivative of amiodarone. It has similar antiarrhythmic effects with amiodarone, but much lesser adverse effects than amiodarone, particularly in those outside the heart. It is suggested to use dronedarone for the rhythm control of atrial fibrillation/flutter, for it has been shown to prevent the recurrence of atrial fibrillation/flutter and reduce rehospitalization in patients with paroxysmal or persistent atrial fibrillation/flutter. Dronedarone is not recommended for the rhythm control in patients with long-term persistent atrial fibrillation or permanent atrial fibrillation, and atrial flutter or atrial fibrillation patients with reduced ejection fraction. Liver function, electrolyte tests and an electrocardiogram should be performed before and after the drug initiation. Potential interactions with other kinds of drugs have to be taken into consideration as well.

Potassium infusion increases the likelihood of conversion of recent-onset atrial fibrillation-A single-blinded, randomized clinical trial.

BACKGROUND: The optimal antiarrhythmic management of recent-onset atrial fibrillation (ROAF) or atrial flutter is controversial and there is a considerable variability in clinical treatment strategies. It is not known if potassium infusion has the potential to convert ROAF or atrial flutter to sinus rhythm (SR). Therefore, we aimed to investigate if patients with ROAF or atrial flutter and plasma-potassium levels ≤4.0 mmol/L have increased probability to convert to SR if the plasma-potassium level is increased towards the upper reference range (4.1-5.0 mmol/L). METHODS: In a placebo-controlled, single-blinded trial, patients with ROAF or atrial flutter and plasma-potassium ≤4.0 mmol/L presenting between April 2013 and November 2017 were randomized to receive potassium chloride (KCl) infusion (n = 60) or placebo (n = 53). Patients in the KCl group received infusions at one of three different rates: 9.4 mmol/h (n = 11), 12 mmol/h (n = 19), or 15 mmol/h (n = 30). RESULTS: There was no statistical difference in the number of conversions to SR between the KCl group and placebo [logrank test, P = .29; hazard ratio (HR) 1.20 (CI 0.72-1.98)]. However, KCl-infused patients who achieved an above-median hourly increase in plasma-potassium (>0.047 mmol/h) exhibited a significantly higher conversion rate compared with placebo [logrank P = .002; HR 2.40 (CI 1.36-4.21)] and KCl patients with below-median change in plasma-potassium [logrank P < .001; HR 4.41 (CI 2.07-9.40)]. Due to pain at the infusion site, the infusion was prematurely terminated in 10 patients (17%). CONCLUSIONS: Although increasing plasma-potassium levels did not significantly augment conversion of ROAF or atrial flutter to SR in patients with potassium levels in the lower-normal range, our results indicate that this treatment may be effective when a rapid increase in potassium concentration is tolerated and achieved.

Direct Oral Anticoagulant Use After Transcatheter Aortic Valve Replacement: A Case Series.

BACKGROUND: Use of an anticoagulant after transcatheter aortic valve replacement (TAVR) has been increasing in practice after noted leaflet thrombosis on dual antiplatelet therapy. As the use of anticoagulation increases so does the number of poor warfarin candidates or warfarin intolerant patients. While direct oral anticoagulant (DOAC) use is increasing for other indications, there is a paucity of data for use after TAVR. The objective of this case series is to add to the available evidence for patients who may require a DOAC after TAVR. METHODS: A single-center, retrospective observational case series was conducted including adults 18 years of age and older who received a DOAC after TAVR between November 2008 and June 2018 at Mayo Clinic Hospital-Rochester. All patients were identified as part of the Society of Thoracic Surgeons database. RESULTS: Twenty-one patients were identified as having received a DOAC after TAVR. Median age was 83.5 years (interquartile range 77-87), with 71% males. Within this cohort, 20 patients (95.2%) had an alternative indication for anticoagulation of either atrial fibrillation or atrial flutter. Apixaban was prescribed in 66.7% of patients, followed by rivaroxaban (14.3%), dabigatran (9.5%), and edoxaban (4.8%). No thromboembolic events were reported. Three patients experienced a bleeding event, of which only 2 occurred in the 3 months immediately after TAVR. CONCLUSIONS: DOAC therapy after TAVR was generally safe and well tolerated. Taken in context of other retrospective studies, these data suggest that the presence of valvular heart disease, specifically TAVR in this case, should not preclude the use of DOACs.