Cardioversion Of Atrial Fibrillation Research Articles

Prospective in silico trials identify combined SK and K2P channel block as an effective strategy for atrial fibrillation cardioversion.

Virtual evaluation of medical therapy through human-based modelling and simulation can accelerate and augment clinical investigations. Treatment of the most common cardiac arrhythmia, atrial fibrillation (AF), requires novel approaches. This study prospectively evaluates and mechanistically explains three novel pharmacological therapies for AF through in silico trials, including single and combined SK and K2P channel block. AF and pharmacological action were assessed in a large cohort of 1000 virtual patients, through 2962 multiscale simulations. Extensive calibration and validation with experimental and clinical data support their credibility. Sustained AF was observed in 654 virtual patients. In this cohort, cardioversion efficacy increased to 82% (535 of 654) through combined SK+K2P channel block, from 33% (213 of 654) and 43% (278 of 654) for single SK and K2P blocks, respectively. Drug-induced prolongation of tissue refractoriness, dependent on the virtual patient's ionic current profile, explained cardioversion efficacy (atrial refractory period increase: 133.0±48.4ms for combined vs. 45.2±43.0 and 71.0±55.3ms for single SK and K2P block, respectively). Virtual patients cardioverted by SK channel block presented lower K2P densities, while lower SK densities favoured the success of K2P channel inhibition. Both ionic currents had a crucial role on atrial repolarization, and thus a synergism resulted from the multichannel block. All three strategies, including the multichannel block, preserved atrial electrophysiological function (i.e. conduction velocity and calcium transient dynamics) and thus its contractile properties (safety). In silico trials identify key factors determining treatment success and the combined SK+K2P channel block as a promising strategy for AF management. KEY POINTS: This is a large-scale in silico trial study involving 2962 multiscale simulations. A population of 1000 virtual patients underwent three treatments for atrial fibrillation. Single and combined SK+K2P channel block were assessed prospectively. The multi-ion channel inhibition resulted in 82% cardioversion efficacy. In silico trials have broad implications for precision medicine.

Prevalence and risk factors associated with decompensated heart failure after successful elective cardioversion for atrial fibrillation and atrial flutter

Study objectiveTo determine the incidence of and risk factors for HF after successful electrical and ablative cardioversion (CV) of atrial fibrillation (AF) and atrial flutter (AFL). DesignRetrospective cohort study. SettingSingle center academic institution. ParticipantsSeven hundred fifty-five patients underwent successful elective CV from July 1, 2018 to May 20, 2019. Patients presenting in arrhythmias other than AF or AFL, those who developed HF due to alternative etiologies, and those who developed arrhythmia recurrence within 30 days were excluded. Medical records of the remaining 451 patients were reviewed before and after CV. Main outcomes measuredDevelopment of heart failure despite sinus rhythm following CV and the risk factors associated with this outcome. ResultsThirty-three (7.3 %) of 451 patients who met inclusion criteria for our study developed new or worsening HF symptoms while maintaining sinus rhythm (SR) after successful CV. Symptoms were reported an average of 5.1 days following CV (range 0–17 days, SD 4.71). Following a multivariate stepwise logistic regression model, prior HF hospitalization (OR 3.91, 95 % CI 1.82–8.39), BMI (OR 1.06, 95 % CI 1.02–1.11), and valve disease (OR 2.51, 95 % CI 1.12–5.60) remained significant risk factors, and anti-arrhythmic drug (AAD) use was marginally significant (OR 2.02, 95 % CI 0.95–4.31). ConclusionDespite maintenance of SR, 7.3 % of patients developed decompensated HF in the 30 days following successful CV of AF or AFL, indicating this complication may be more frequent than previously believed. Predictors of HF post-CV included elevated BMI, valve disease, previous HF hospitalization, and prior AAD use.

Cluster-specific predictors of early rhythm control in contemporary European cohort of patients with atrial fibrillation: The EHRA-PATHS Project

Abstract Background Early rhythm control (ERC) using antiarrhytmic drugs, electrical cardioversion or catheter ablation for AF within a year from first diagnosis of atrial fibrillation (AF) has been shown to reduce the risk of major adverse outcomes compared to usual care, and the effects of ERC have been suggested to be consistent across all AF subgroups with different risk profiles. We aimed to identify cluster-specific predictors of ERC in pre-defined AF clusters in contemporary European EHRA-PATHS AF cohort. Methods The EHRA-PATHS AF cohort was derived from the three prospective EurObservational Research Programme (EORP) AF registries - General Pilot, General Long-term, and AF III registry. A two-step cluster analysis was performed. A hierarchical cluster analysis with 18 variables was used to identify the optimal number of clusters, followed by a K-means cluster analysis to determine variable cluster association. Cluster-specific predictors of ERC were identified using univariate and multivariate logistic regression analyses. Results Of 18,799 patients, AF was diagnosed within 1 year in 8088 (43.0%), and 3913/8088 patients (48.4%) were treated with ERC. Among the three clusters - Cluster 1 (younger healthier AF patients) compared with Cluster 2 (Elderly with less comorbidity, mostly non-cardiovascular) and Cluster 3 (Elderly with more comorbidity, mostly cardiovascular), see Table, ERC was significantly more often used in Cluster 1 compared with Cluster 2 and Cluster 3 (both P<0.001), and in Cluster 2 compared with Cluster 3. Cluster-specific multivariable predictors of ERC are shown in Table. In all three clusters, asymptomatic AF (EHRA score I) and Northern Europe residence were inversely associated with ERC, while Western Europe residence was positively associated with ERC in Cluster 2 and 3. In Cluster 1, low stroke risk and hypertension were positively associated with ERC, while dilated left atrium (LA) and reduced left ventricular ejection fraction (LV EF) were negative predictors of ERC. In Cluster 2, age ≥80 years, enlarged LA, and CHA2DS2-VASc ≥2 for males and ≥3 for females were negatively associated with ERC. In Cluster 3, age ≥75 years, cardiomyopathy, liver disease, dementia and reduced LV EF were negative predictors of ERC. Conclusion Our study of a large European AF cohort showed that likelihood for ERC was greater in younger and healthier AF patients, as well as in elderly from Western Europe, while ERC was significantly less likely with increasing age and comorbidity (especially cardiovascular diseases). These findings likely reflect the lack of high-quality evidence supporting aggressive ERC in high-risk patients with AF. With increasing body of evidence favouring ERC such patients, a shift towards less selective consideration of ERC in daily practice may be expected.

Atrial function after cardioversion in patients with persistent atrial fibrillation

Abstract Background After cardioversion for persistent atrial fibrillation (AF), restitution of normal left atrial (LA) function is said to need several days to recover. However, in previous studies, the evaluation of LA function was only used transesophageal or transthoracic echocardiography. During catheter ablation (CA) for AF, pulmonary venous (PV) blood flow can be measured accurately using an intracardiac echocardiogram (ICE). The atrial systolic PV regurgitation (PVa) wave measured by ICE is a good indicator of LA contractility because it reflects the active contraction of the LA. Purpose This study aims to investigate the LA function in the hyperacute phase and the factors which affect after cardioversion. Methods 40 AF patients (18 paroxysmal AF, 22 persistent AF) who underwent CA were enrolled. PVa wave was measured twice before RFCA and after the procedure using intracardiac ultrasound. Voltage map of the LV was obtained using the CARTO system at the end of the session, and the percentage of low voltage area which was determined area as less than 0.1mV in the mapped LA surface area (LVA%) was calculated. Results Preoperative PVa was 1.61 ± 0.09 m/sec in the paroxysmal AF group (PaAF), and no PVa was observed in the persistent AF group (PeAF). Postoperative PVa were comparable between PaAF (0.18±0.06 m/sec) and PeAF (0.18±0.07 m/sec). Then, the PeAF were divided into 2 groups based on LVA% in the anterior area, posterior area, and total LA area (cutoff 1,5 and 10%, respectively). In the anterior lower LVA% group, PVa were significantly increased (0.20 ± 0.07 m/sec) after defibrillation compared with the anterior higher LVA% group (0.14 ± 0.06 m/sec; P=0.02), whilst no difference was observed when it was divided in the posterior wall or overall. Conclusion Even in PeAF, LA function improves to the same degree as in the PaAF immediately after cardioversion, and the posterior wall LVA, including posterior wall isolation, may not affect LA function.

Inflammation and long-term outcomes after first-time direct current cardioversion for atrial fibrillation: a nationwide register study

Abstract Background Emerging evidence suggests that the pathogenesis of atrial fibrillation (AF) is affected by inflammatory processes which contribute to structural and electrical remodeling of the atria, creating a substrate for arrythmia. Aim To assess whether inflammation measured by C-reactive protein (CRP) is associated with readmission for direct current (DC) cardioversion, ablation, heart failure or stroke after discharge from 1st time DC cardioversion. Methods This nationwide retrospective cohort study included patients undergoing 1st DC cardioversion between 2011 and 2018. Exclusion criteria were death within one day of cardioversion and no available CRP at baseline. Primary outcome was readmission for DC cardioversion of AF. Secondary outcomes were AF ablation, new admission of stroke, new admission of heart failure (HF), and all-cause death. Absolute risk rates (ARR) of outcomes were calculated for patients with available 1-year follow-up data. CRP 20 mg/L was chosen as cutoff to establish a clinically relevant borderline for inflammation. The association between baseline CRP and outcome was assessed in Cox proportional hazards regression models with a follow-up period starting from 1st DC cardioversion, ending no later than 31st of December 2018, for the entire study population (n=9,977). Results After exclusion criteria the study population consisted of 9,977 patients Mean age for CRP > 20mg/L: 66.8 (IQR: 60.5-74.2). Mean age for CRP < 20mg/L 68.9 (IQR: 62.9-75.9)(p<0.001). In total, 68.9% were male and the most frequent comorbidities included hypertension (57.3%), ischemic heart disease (25.1%), HF (20.6%), and history of stroke (7.1%). Patients with available CRP measurement and 1yr follow up was 7,764. Compared to patients with low CRP (<20 mg/L), patients with elevated CRP (>20mg/L) had a higher 1-year ARR of HF, and all cause death (p<0.001). Compared to patients with low CRP, patients with elevated CRP had a lower 1-year ARR of all-ablation and new DC cardioversion (p<0.001), (Table 1). CRP > 20mg/L was associated with lower risk for new DC cardioversion (HR 0.72, 95% CI: 0.64-0.82, p<0.001). However, in patients <75 years of age with CRP > 20mg/L at baseline had an increased risk of stroke after multivariable adjustments (HR 1.92, 95% CI: 1.10-3.35; p = 0.02) (Fig.1), while CRP > 20 mg/L was not associated with an increased risk of stroke in patients > 75yrs of age (Cox regressions estimates) (p for interaction = 0.03). Conclusion However, elevated CRP was associated with an increased risk of stroke in patients <75 years of age, even after multivariable adjustments. These results suggest that CRP may not be a reliable predictor of readmission for DC-cardioversion, especially in older individuals, but might be a potential risk stratification tool in identifying AF patients at higher risk of stroke in young individuals. We suspect this is due to the population with elevated CRP has more comorbidities and are older.

Transoesophageal echocardiography-guided cardioversion and thromboembolism

Abstract Background To perform electrical cardioversion of atrial fibrillation or atrial flutter with a duration of more than 48 hours, it is recommended to initiate anticoagulation therapy for at least three weeks beforehand. In cases where cardioversion is necessary earlier, it is suggested to precede the procedure with a transoesophageal echocardiography to rule out the presence of a thrombus in the left atrium (referred to as TOE-guided cardioversion). This strategy is outlined in current ESC guidelines for atrial fibrillation. However due to limited evidence, no specific level of recommendation for its use is provided. Purpose This study aimed to characterize patients treated by TOE-guided cardioversion in two hospitals and to conduct a safety analysis of the procedure. The 30-day incidence of thromboembolic events was chosen as the main safety objective, the 30-day mortality as the secondary. Method This was a retrospective, two center, cohort register study where information was obtained from patients medical records. All patients who underwent TOE-guided cardioversion between 2012-2020 in the first institute, and between 2015-2020 in the second were included. From the medical records all the patient characteristics and the clinical outcomes were identified. Result A total of 259 patients, with TOE-guided cardioversions, arrhythmia duration over 48 hours and without adequate anticoagulation therapy were included. Patient characteristics are shown in table 1. It was equal incidence of a 30-day thromboembolic event (n=6) and the 30-day mortality (n=6), 2,3% respectively. Three of the six patients died of non-cardiovascular cause. One of the 30-day thromboembolic event resulted in mortality at day 31. Table 2 summarize the data related to the thromboembolic events. There was no statistically significant predictor of any of the two endpoints when comparing the patients with event and patients without. Conclusion This study shows that the risk of thromboembolic events after TOE-guided cardioversion is not negligible, 2,3% within a 30-day follow up. The 30-day mortality was 2,3%, half of which were non-cardiovascular. To analyse potential clinical predictors for any events, larger studies specifically powered for such a question is needed.

DC cardioversion of atrial fibrillation

Direct current (DC) cardioversion is an everyday clinical procedure used to restore sinus rhythm from atrial fibrillation. This review summarises the current state of art in Denmark. Sufficient anticoagulation must be ensured before DC cardioversion to reduce the risk of thromboembolism. Biphasic maximum energy shocks delivered via anterolateral electrodes are recommended. Overall success is high, and the complication rate is low. Relapse of atrial fibrillation is common, and a long-term treatment strategy which may include antiarrhythmics, ablation and lifestyle change should be established in collaboration with the patient.

6415 Resistance to Thyroid Hormone -A Challenge to Manage

Abstract Disclosure: A. Altaf: None. F. Iqbal: None. E. Hamoudeh: None. C. Coyne: None. K. Anne: None. L. Buckley: None. Background: Resistance to thyroid hormone (RTH) or Refetoff syndrome was first introduced in 1967. It is an autosomal dominant or recessive genetic disease with a mutation in the thyroid hormone receptorβ (THR-β) gene or the thyroid hormone receptorα (THR-α) gene. The distinguishing biochemical feature of RTHβ is an elevated level of circulating free thyroid hormones with normal or high TSH concentration and decreased peripheral tissue response to thyroid hormone. Common signs and symptoms in patients with RTHβ are short stature, attention deficit disorder, and resting tachycardia and many patients might be asymptomatic. Case: We report a case of a 36-year-old patient with past medical history of congenital bilateral hearing loss, atrial fibrillation, CHF, and slow learning/comprehending who presented to the ER with shortness of breath and atrial fibrillation with tachycardia. Admission labs revealed elevated TSH 3.9, elevated fT4 3.28, and elevated TT3 205. He reported that for the past year, he has been on levothyroxine 50mcg for abnormal TSH. Levothyroxine was stopped and the patient was discharged on methimazole 10mg daily. Further workup revealed negative thyroglobulin and thyroid peroxidase antibodies. Thyroid ultrasound with Doppler demonstrated a mildly hypervascular thyroid gland without evidence of nodules. Brain MRI was negative for any pituitary abnormalities. HAMA testing continued to show elevated TSH. Patient was followed by cardiology and due to continued atrial fibrillation, had multiple cardioversions and was managed on a beta blocker. Due to his atrial fibrillation, endocrinology service continued his methimazole till his genetic testing came positive for an autosomal dominant heterozygous pathogenic mutation in THRB c.1373 T>C (p. Val458Ala). His thyroid hormones and TSH continue to be elevated. Currently, he is not on thyroid medication and getting monitored. The need for multiple cardioversions for atrial fibrillation in this patient makes resistance to thyroid hormone management challenging. Discussion: Hyperthyroidism is commonly mistaken for RTH. However, the lack of TSH suppression should be further investigated. Most patients with RTHβ are adequately compensated by the increased endogenous supply of thyroid hormone showing increased serum fT3 and fT4 levels and normal or near normal TSH levels. Beta Blockers like atenolol cannot inhibit the conversion of T4 to T3 and can be used for RTHβ with tachycardia. Triiodothyroaceticacid (TRIAC) or dextrothyroxine (DT4) have also been used to treat thyrotoxicosis. In summary, treatment for RTHβ remains a challenge for clinicians, especially in patients with atrial fibrillation and many patients are misdiagnosed and managed as hyperthyroidism. Presentation: 6/3/2024

The Efficacy of I Na Block to Cardiovert Atrial Fibrillation Is Enhanced by Inhibition of I K1.

There is a need for more efficient pharmacological cardioversion of atrial fibrillation (AF). We tested the hypothesis that inhibition of I K1 significantly enhances the efficacy of I Na block to depress atrial excitability and to cardiovert AF. The study was conducted in canine isolated arterially perfused right atrial preparations with rim of ventricular tissue. AF was induced in the presence of acetylcholine (ACh; 0.5 µM). BaCl 2 (10 µM) was used to inhibit I K1 and flecainide (1.5 µM) to block I Na . Sustained AF (>45 minutes) was recorded in 100% atria (5/5) in the presence of ACh alone. Flecainide cardioverted AF in 50% of atria (4/8), BaCl 2 in 0% (0/5), and their combination in 100% (5/5). AF cardioversion occurred in 15 ± 9 minutes with flecainide alone (n = 4) and in 8 ± 9 minutes with the combination (n = 5). Following drug-induced AF cardioversion, AF was inducible in 4/4 atria with flecainide alone (≤5 minutes duration) and in 2/5 atria with the combination (≤30 seconds duration). Atrial excitability was significantly more depressed by combined versus monotherapies. There was little to no effect on ventricular excitability under any condition tested. Thus, inhibition of I K1 significantly enhances the efficacy of flecainide to depress atrial excitability and to cardiovert AF in our experimental setting. A combination of I Na and I K1 inhibition may be an effective approach for cardioversion of AF.

Manual Chest PRESSURE During Direct Current Cardioversion for Atrial Fibrillation: A Randomized Control Trial (PRESSURE-AF)

BackgroundDirect current cardioversion is frequently used to return patients with atrial fibrillation (AF) to sinus rhythm. Chest pressure during cardioversion may improve the efficacy of cardioversion through decreasing transthoracic impedance and increasing cardiac energy delivery. ObjectivesThis study aimed to assess the efficacy and safety of upfront chest pressure during direct current cardioversion for AF with anterior-posterior pad positioning. MethodsThis was a multicenter, investigator-initiated, double-blinded, randomized clinical trial. Recruitment occurred from 2021 to 2023. Follow-up was until hospital discharge. Recruitment occurred across 3 centers in New South Wales, Australia. Inclusion criteria were age ≥18 years, referred for cardioversion for AF, and anticoagulation for 3 weeks or transesophageal echocardiography excluding left atrial appendage thrombus. Exclusion criteria were other arrhythmias requiring cardioversion, such as atrial flutter and atrial tachycardia. The intervention arm received chest pressure during cardioversion from the first shock. The primary efficacy outcome was total joules required per patient encounter. Secondary efficacy outcomes included first shock success, transthoracic impedance, cardioversion success, and sinus rhythm at 30 minutes post cardioversion. ResultsA total of 311 patients were randomized, 153 to control and 158 to intervention. There was no difference in total joules applied per encounter in the control arm vs intervention arm (355.0 ± 301 J vs 413.8 ± 347 J; P = 0.19). There was no difference in first shock success, total shocks provided, average impedance, and cardioversion success. ConclusionsThis study does not support the routine application of chest pressure for direct current cardioversion in atrial fibrillation (PRESSURE-AF [Investigating the Efficacy of Chest Pressure for Direct Current Cardioversion in Atrial Fibrillation: A Randomized Controlled Trial]; ACTRN12620001028998)

Risk of stroke with reduced dose direct oral anticoagulants vs standard dose anticoagulation after cardioversion of atrial fibrillation: A systematic review and meta-analysis

Risk of stroke with reduced dose direct oral anticoagulants vs standard dose anticoagulation after cardioversion of atrial fibrillation: A systematic review and meta-analysis

Defibrillation of Atrial Fibrillation is not Associated with Increased Risk of Ventricular Fibrillation – The VCD-Trial (Clinical Trial of Electrical Therapy for Atrial Fibrillation using R-wave Guided Cardioversion Versus Defibrillation)

Background: Because of a possible risk of induction of Ventricular Fibrillation (VF) by defibrillation of atrial fibrillation (AF) postulated by LOWN and coworkers, synchronized cardioversion is used worldwide. This prospective, randomized study assessed the efficacy and safety between R-wave controlled cardioversion and defibrillation of AF at 2 study centers in Cologne, Germany. Hypothesis: Defibrillation is not significantly different from cardioversion primarily in the occurrence of VF or sustained Ventricular Tachycardia (VT) and secondarily in restoring sinus rhythm, inducing non-sustained VT, asystole, or bradycardia. Methods: 146 patients at an outpatient practice and 122 at the university hospital were randomized to cardioversion (n = 140) or defibrillation (n = 124). Results: Cardioversion was successful in 92.1% of cases and defibrillation in 87.1%. The difference in efficacy was not statistically significant. In n = 1 patients receiving defibrillation, VF occurred after the first shock (200J) and immediate defibrillation (200J) restored sinus rhythm. In the n = 1 case, asystole occurred during cardioversion which terminated spontaneously. In n = 1 patients cardioverted and n = 2 who were defibrillated, sinus bradycardia occurred requiring Atropine in two cases. There were no thromboembolic events within 10 days. N = 9 patients reverted to AF within two hours. No patients died. Conclusion: Electrical conversion of AF can be performed with similar results and low risk with both R-wave-triggered cardioversion and defibrillation. In particular, defibrillation with higher energies (> 100J) can be performed as effectively and safely without a statistically significant increased risk of VF or VT. There was no difference in efficacy and risk between electrotherapy performed in the outpatient and inpatient settings.

Evaluation of Changes in Cardiac Troponin I Levels After Direct Current Cardioversion in Patients With Atrial Fibrillation.

Direct current cardioversion (DCCV) of atrial fibrillation (AF) is a procedure used to restore normal heart rhythm. Cardiac biomarkers, such as cardiac troponin I (cTnI), are elevated in situations where injury-myocardial cell necrosis is induced. The aim of the present study was to investigate the change in cTnIlevels, i.e., whether a myocardial injury is present, in patients with AF whose elective treatment was synchronized DCCV via a biphasic defibrillator. The study sample included 59 patientswho underwent synchronized DCCV for AF reversion. Measurement of cTnI before and after DCCV (one, three, and six hours) was performed by blood sampling and subsequent assay. It was observed that the value of cTnI did not change (<0.1 ng/mL) after DCCV at the measurement time points (one, three, and six hours). In addition, the value of cTnI remained constant (<0.1 ng/mL) in relation to the energy delivered, before DCCV and after DCCV (one, three, and six hours). However, it was found that there was a correlation between the outcome (AF reversion or not) and the energy used (joules). Synchronized DCCV with a biphasic defibrillator did not cause myocardial injury in any of the patients, as there was no change in cTnI values before and after DCCV.

Elective direct current cardioversion of atrial fibrillation - silent brain infarction and health related quality of life.

Atrial fibrillation (AF) increases the risk for stroke, dementia and impaired health related quality of life (HRQL). Elective direct current cardioversion (ECV) is often used to restore sinus rhythm, but is associated with thromboembolism. While larger strokes usually produce symptoms, subclinical ones may go unrecognized and may cause cognitive and functional decline over time. In the current study, we sought to evaluate the effects of ECV on silent brain infarctions and HRQL in patients with AF. Patients with AF (n=46) underwent brain magnetic resonance imaging (MRI) and HRQL assessment using the EuroQL-5D5L questionnaire before and after ECV. Implantable loop recorders (ILR) were used to observe the rate of early AF recurrences within the first thirty days. All patients were treated with anticoagulants according to guidelines. The primary endpoint was silent brain infarction assessed by brain MRI within the first two weeks after ECV. Secondary endpoints were the change in HRQL and its association with AF recurrence at follow-up and by ILR recordings. New silent brain infarction after ECV was detected in one patient. At follow-up visit after 19.1 days AF recurrence was detected by 12-lead ECG in 13 patients (28.3 %), whereas 27 patients (58.7 %) had AF recurrence recorded by ILR within the first thirty days after ECV. European Heart Rhythm Association (EHRA) symptom score and the EuroQL-5d5L score were improved after ECV. Silent brain infarctions may occur after ECV despite anticoagulation treatment. Early AF recurrence is frequent. ECV positively affects HRQL mainly in those patients with sustained sinus rhythm at follow-up.

Left atrial appendage thrombus in patients with atrial fibrillation who underwent oral anticoagulation.

Electric cardioversion of atrial fibrillation (AF) is associated with an increased risk of embolism, with embolic material existing in the heart cavities. The initiation of oral anticoagulation therapy reduces the risk of thromboembolic events. The aims of this study were to evaluate the prevalence of left atrial appendage (LAA) thrombi in non-valvular AF, to compare vitamin K antagonists (VKAs) and non-vitamin K oral anticoagulants (NOACs) with respect to thrombus prevalence, and to evaluate the rate of LAA thrombus persistence on repeat transesophageal echocardiography (TEE) after treatment change. We enrolled 160 consecutive AF patients who presented with an AF duration > 48 h and had undergone TEE before cardioversion. Left atrial appendage thrombus was observed in 12 (7.5%) patients, and spontaneous echo contrast 4 was observed in 19 (11.8%) patients; the incidence was similar between the NOAC and VKA groups (8.9% vs. 3.6% and 12.4% vs. 18.5 %, respectively). Among patients on NOAC, thrombus prevalence was detected in 8.4% of users of rivaroxaban, 8% of users of dabigatran, and 12.5% of users of apixaban. The LAA thrombus developed in 7.5% of patients despite anticoagulation therapy, demonstrating similar prevalence rates among patients either on NOAC or VKA. Lower mean LAA flow velocity and a history of vascular disease were independent predictors of embolic material in the LAA. It seems that in the case of embolic materials in LAA under NOAC treatment, switching to VKA provides additional clinical benefit to the patients.

Bradycardic peri-arrest after electrical cardioversion for atrial fibrillation: a case report

Electrical cardioversion can precipitate prolonged bradycardia and cardiac arrest when the sinoatrial node is dysfunctional, and the escape rhythms from the atrioventricular node and ventricles fail to take over. We report the case of an elderly male who rapidly progressed into bradycardic peri-arrest after electrical cardioversion for persistent atrial fibrillation. Despite the immediate initiation of intravenous atropine and transcutaneous pacing, 2 minutes of cardiopulmonary resuscitation with further boluses of atropine and adrenaline were required before the return of spontaneous circulation. The patient was transferred to the intensive care unit, and a permanent pacemaker was implanted before discharge. Advanced age, long duration of atrial fibrillation, previous aortic valve replacement, use of anti-arrhythmic drugs, and intravenous propofol bolus were all contributing factors to this event. We summarise the relevant clinical features, risk factors, and management considerations, in the hope of promoting awareness of this rare complication of a common procedure.

Acute Management of Paroxysmal Atrial Fibrillation with Intravenous Flecainide plus Oral Beta-Blockers

Background: Intravenous (IV) flecainide is recommended for the pharmacological cardioversion of recent-onset atrial fibrillation (AF). The aim of this study was to study the efficacy and safety of IV flecainide, co-administered with oral b-blockers, for the cardioversion of paroxysmal AF. Methods: Single-center registry, initiated in the “Skylitseion” General Hospital of Chios in January 2020. The main inclusion criterion was IV flecainide administration plus oral b-blocker for recent-onset AF (≤48 h). The primary outcome was conversion to sinus rhythm at 2 h. Results: A total of 121 (73 males and 48 females, with mean age 61.4 years) consecutive, unselected patients who complied with the study protocol were included. A successful conversion to sinus rhythm at 2 h was achieved in 99 patients (success rate: 81.8%). The median conversion time was 11.7 min (varied from 3 to 23 min). Duration of hospitalization was significantly shorter in patients who were successfully cardioverted with IV flecainide (10.9 vs. 30.7 h, p &lt; 0.001). No serious adverse events were recorded. Conclusion: This is one of the largest registries worldwide, evaluating the effectiveness and safety of IV flecainide co-administered with a b-blocker in the acute management of recent-onset AF. The successful conversion rate at 2 h is very high and quick with no serious adverse events.

External electrical and pharmacological cardioversion for atrial fibrillation, atrial flutter or atrial tachycardias: a network meta-analysis.

External electrical and pharmacological cardioversion for atrial fibrillation, atrial flutter or atrial tachycardias: a network meta-analysis.

Thromboembolic and bleeding complications after elective cardioversion of atrial fibrillation: a nationwide cohort study.

Elective cardioversion (ECV) is routinely used in atrial fibrillation (AF) to restore sinus rhythm. However, it includes a risk of thromboembolism even during adequate oral anticoagulation treatment. The aim of this study was to evaluate the risk of thromboembolic and bleeding complications after ECV in a real-life setting utilizing data from a large AF population. This nationwide register-based study included all (n = 9625) Finnish AF patients undergoing their first-ever ECV between 2012 and 2018. The thromboembolic and bleeding complications within 30 days after ECV were analysed. The mean age of the patients was 67.7 ± 9.9 years, 61.2% were men, and the mean CHA2DS2-VASc score was 2.6 ± 1.6. Warfarin was used in 6245 (64.9%) and non-vitamin K oral anticoagulants (NOACs) in 3380 (35.1%) cardioversions. Fifty-two (0.5%) thromboembolic complications occurred, of which 62% were ischaemic strokes, 25% transient ischaemic attacks, and 13% other systemic embolisms. Thromboembolic events occurred in 14 (0.4%) NOAC-treated patients and in 38 (0.6%) warfarin-treated patients (odds ratio 0.77; confidence interval: 0.42-1.39). The median time from ECV to the thromboembolic event was 2 days, and 78% of the events occurred within 10 days. Age and alcohol abuse were significant predictors of thromboembolic events. Among warfarin users, thromboembolic complications were more common with international normalized ratio (INR) <2.5 than INR ≥2.5 (0.9% vs. 0.4%, P = 0.026). Overall, 27 (0.3%) bleeding events occurred. The rate of thromboembolic and bleeding complications related to ECV was low without significant difference between NOAC- and warfarin-treated patients. With warfarin, INR ≥2.5 at the time of cardioversion reduced the risk of thromboembolic complications.

Mechanical atrial recovery by speckle-tracking echocardiography in the prediction of recurrence at 2 years after successful cardioversion of persistent atrial fibrillation

Mechanical atrial recovery by speckle-tracking echocardiography in the prediction of recurrence at 2 years after successful cardioversion of persistent atrial fibrillation