Strategies for Successful Electrical Cardioversion in Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in the world, and its management relies on restoring sinus rhythm through external electrical shock and controlling the heart rate. This procedure should be performed under sedation with strict monitoring of blood pressure and saturation after the elimination of thrombus in the left atrium. Objective: The aim of this article is to provide an overview of the impact of anticoagulation and imaging in the periprocedural period, the modalities, and the complications associated with electrical cardioversion (ECV). Research Method: A review of recent literature was conducted using medical databases such as PubMed and Scopus. Searches were performed on articles published between 2003 and 2024, focusing on the new ESC guidelines for 2024. The keywords used included “electrical cardioversion”, “atrial fibrillation”, “orthogonal cardioversion” and “anticoagulation”. Inclusion criteria encompassed clinical trials, meta-analyses, and literature reviews, while studies addressing other treatment forms for AF or lacking information on ECV were excluded. Relevant data were extracted and synthesized to provide an overview of the modalities and complications related to ECV in the context of AF. Results and Conclusion: The use of high-energy biphasic shocks significantly improves rhythm control success and also reduces the incidence of ventricular fibrillation. Furthermore, orthogonal electrical cardioversion (OECV) has proven effective for cases of AF refractory to standard protocols, allowing for a lower defibrillation threshold and promoting better current distribution. However, complications must be considered, particularly thromboembolic events in non-anticoagulated patients. Other complications, such as bradycardia and recurrence of AF, may arise post-procedure. It is therefore crucial to ensure adequate anticoagulation before and after ECV, as well as continuous monitoring, to minimize these risks and optimize clinical outcomes.

Emergency department procedural sedation for primary electrical cardioversion — a comparison with procedural sedations for other reasons

BACKGROUND: Atrial fibrillation(AF) is the most common arrhythmia treated in the emergency department(ED), with primary electrical cardioversion(PEC) the preferred method of rhythm control. Anecdotally, patients undergoing ED procedural sedation(EDPS) for PEC differ from those requiring EDPS for other procedures: they are at higher risk of adverse events, and require fewer drugs and lower doses. We attempt to verify this using an EDPS registry at a Canadian, tertiary care teaching hospital.METHODS: This is a retrospective review of patients that underwent EDPS for the period of June 2006 to September 2014. We compared demographics, medication use and intra-procedural adverse events between those receiving EDPS for PEC for AF compared to that for other indications. We report the asssociation between AEs and predictors using logistic regression.RESULTS: A total of 4 867 patients were included, 714 for PEC for AF and 4 153 for other indications. PEC patients were more likely male(58.5% vs. 47.1%), older(59.5 years vs. 48.1 years), and less likely to be ASA I(46.6% vs. 69.0%). PEC patients received smaller doses of propofol and less likely to receive adjuvant analgesic therapy(11.5% vs. 78.2%). PEC patients were more likely to experience hypotension(27.6% vs. 16.5%) but respiratory AEs(apnea, hypoxia and airway intervention) were not different.CONCLUSION: EDPS for PEC differs from that conducted for other purposes: patients tend to be less healthy, receive smaller doses of medication and more likely to suffer hypotension without an increase in respiratory AEs. These factors should be considered when performing EDPS.

Understanding the effect of propofol and electrical cardioversion on the systolic blood pressure of emergency department patients with atrial fibrillation

Dear editor, We read with pleasure the well-designed study by Butler et al of electrical cardioversion of emergency department patients with atrial fibrillation. We appreciate their analysis of the distinctives of procedural sedation when employed for this indication. Understanding the dosing adjustments to propofol undertaken by their sedationists will help us more carefully evaluate our own approach to sedating patients undergoing electrical cardioversion of atrial fibrillation.

Electrical cardioversion for supraventricular arrhythmias in octagenarians

Atrial fibrillation(AF)is the most common arrhythmia in the elderly and its incidence increases with aging.[1]Electrical cardioversion is used as a strategy for rhythm control in patients with supraventricular arrhythmias.In octagenarians,there are challenges associated with the indication for electrical cardioversion,such as the use of appropriate sedation and anticoagulant agents.Most decisions in clinical practice for these patients derive from observational data and personal experience,since octagenarians represent a minority of patients included in randomized clinical trials.Little evidence is available regarding the clinical context of electrical cardioversion in this vulnerable population.Therefore,we aimed to describe the clinical profile of octagenarians undergoing electrical cardioversion in a cardiology reference center from 2014 to 2018.

Long-term efficacy and safety of very-low-dose amiodarone treatment for the maintenance of sinus rhythm in patients with chronic atrial fibrillation after successful direct-current cardioversion

Background Long-term maintenance of sinus rhythm after successful conversion of chronic atrial fibrillation （CAF）, often ameliorates patients＇ symptoms, reduces the risk of ischemic stroke and improves cardiovascular hemodynamics. This prospective study aims to evaluate the long-term efficacy and safety of very low-dose amiodarone （100 mg daily） for the maintenance of sinus rhythm after successful direct-current （DC） cardioversion in patients with CAF and rheumatic heart disease （RHD） post intervention. Methods This study was a randomized prospective trial. One day after successful DC cardioversion （remained normal sinus rhythm） in patients with CAF and RHD post intervention for more than six months and adequate anticoagulation, all were randomly administered either amiodarone 200 mg daily in group A or amiodarone 100 mg dally in group B. Results A total of 76 patients （40 men and 36 women） were examined from February 1998 to December 1999. The mean age of the patients was （664- 10） years, and the mean follow-up was （674-8） months （range 61 to 84 months）. Actuarial rates of the maintenance of sinus rhythm were similar in the two groups after 5 years of follow-up. Four patients （11%） in group A but none in group B experienced significant adverse effects that necessitated withdrawal of amiodarone. No death occurred during the study period. Conclusion A very low dose of amiodarone results in adequate long-term efficacy and is safe for maintaining sinus rhythm in patients with CAF and RHD post intervention after successful DC cardioversion.

Predictors of left atrial appendage stunning after electrical cardioversion of non-valvular atrial fibrillation

Objective To identify predictors of left atrial appendage stunning after the use of electrical cardioversion to restore sinus rhythm in patients with non-valvular atrial fibrillation. Methods A total of 68 consecutive patients (45 men,23 women,60.5±8.7 years of age) with non-valvular atrial fibrillation undergoing electrical cardioversion were enlisted in this study. Clinical and echocardiographic variables were analyzed by univariate regression and multivariate logistic regression to investigate the relationship between occurrences of left atrial appendage stunning and these factors. Results Univariate analysis revealed that,in comparing patients without and with left atrial appendage stunning,there were significant differences in the duration of atrial fibrillation > 8 weeks (32.3% vs 75.5%,P <0.001),left atrial diameter > 50 mm (29.0% vs 54.1%,P <0.05),left atrial emptying fraction (31.5%±7.8% vs 27.1%±8.5%,P <0.05),left ventricular ejection fraction < 50% (38.7% vs 67.6%,P <0.05),maximum electrical energy (96.8 J±65.8 J vs 156.8 J±100.8 J,P <0.01),cumulative electrical energy 146.8 J±142.6 J vs 290.5 J±242.1 J, P <0.01) and number of electrical cardioversion shocks (1.7±0.9 vs 2.43±1.20,P <0.05). However,backward stepwise multivariate logistic regression analysis identified as significant and independent predictors of left atrial appendage stunning only duration of atrial fibrillation > 8 weeks (OR=7.249,95%CI=1.998-26.304, P <0.01),left atrial diameter > 50 mm (OR=3.896,95%CI=1.105-13.734,P <0.05),left ventricular ejection fraction < 50% (OR=4.465,95%CI=1.51713.140, P <0.01) and cumulative energy of electrical cardioversion (OR=1.004,95%CI=1.000-1.008, P <0.05). Conclusions Duration of atrial fibrillation >8 weeks,left atrial diameter >50 mm,left ventricular ejection fraction <50%,and cumulative energy of electrical cardioversion are independent predictors of left atrial appendage stunning. Anticoagulation treatment should be individualized for patients undergoing electrical cardioversion to reduce the risk of both cardioversion-related thromboembolic events and hemorrhagic complications caused by warfarin treatment.

Incidence and causes of inappropriate detection and therapy by implantable defibrillators of cardioversion in patients with ventricular tachyarrhythmia

Background Implantable cardioverter defibrillator （ICD） is the only effective therapy in patients with life threatening ventricular arrhythmias. Inappropriate detection and therapy by ICDs are the most common causes of side effects that affect the quality of life in ICD recipients. This study evaluated the incidence and causes of inappropriate detection and therapy by ICDs in patients in our hospital. Methods From January 2000 to December 2005, fifty patients who received ICD implantation for ventricular arrhythmias for prevention of sudden cardiac death were evaluated in this study. Each ICD was programmed using clinical arrhythmic and cardiac data of the patient before discharge. Patients were followed up by standard schedule after implantation and all data retrieved from each device were collected and saved for further analysis. Results No arrhythmic event was detected in 12/50 （24%） patients during the period of follow-up. Among the remaining patients, 11 （22%） experienced inappropriate detections and therapies during follow-up in this study. ICD detected 383 ventricular tachyarrhythmia （VT） and 108 ventricular fibrillation （VF） episodes and delivered 678 therapies. In VT group, ICD delivered 413 antitachycardiac pacings （ATPs） and 118 shocks, among which 78 ATPs and 9 shocks were initiated by 55/383 （14.3%） inappropriate detections. In VF group ICD delivered 147 shocks, among which 56 shocks were initiated by 28/108 （26.9%） inappropriate detections. Overall, more than 50% of these episodes were caused by atrial fibrillation （AF） with rapid ventricular response, followed by electromagnetic or myopotential interference. In addition, most inappropriate therapies occurred within one year after ICD implantation. Conclusions About one fifth of patients experienced ICD inappropriate detection and therapy after implantation. The main cause was AF with rapid ventricular response, followed by electromagnetic or myopotential interference.

Atrial fibrillation in obstructive sleep apnea

Atrial fibrillation(AF) is a common arrhythmia with rising incidence.Obstructive sleep apnea(OSA) is prevalent among patients with AF.This observation has prompted significant research in understanding the relationship between OSA and AF.Multiple studies support a role of OSA in the initiation and progression of AF.This association has been independent of obesity,body mass index and hypertension.Instability of autonomic tone and wide swings in intrathoracic pressure are seen in OSA.These have been mechanistically linked to initiation of AF in OSA patients by lowering atrial effective refractory period,promoting pulmonary vein discharges and atrial dilation.OSA not only promotes initiation of AF but also makes management of AF difficult.Drug therapy and electrical cardioversion for AF are less successful in presence of OSA.There has been higher rate of early and overall recurrence after catheter ablation of AF in patients with OSA.Treatment of OSA with continuous positive airway pressure has been shown to improve control of AF.However,additional studies are needed to establish a stronger relationship between OSA treatment and success ofAF therapies.There should be heightened suspicion of OSA in patients with AF.There is a need for guidelines to screen for OSA as a part of AF management.

Approach to Paroxysmal Atrial Fibrillation Type Arrhythmia in a Cardiology Service:A Case Report

Atrial fibrillation is a cardiac arrhythmia of high prevalence in the population, especially in the elderly. Its main electrical characteristics are the interval between two successive irregular R waves, absence of P waves and presence of f waves between QRS complexes. The most common symptoms of atrial fibrillation are irregular palpitations associated with dyspnea, dizziness, feeling tired, fatigue and general malaise, but not all patients have any symptoms. The present report presents the history of an elderly patient who arrived at the hospital’s emergency department with irregular heart rhythm and palpitations. The patient’s symptoms, associated with the electrocardiogram results, indicated paroxysmal atrial fibrillation. Electrical cardioversion was performed, and after, cardiac ablation via the femoral vein at the hospital’s cardiology service. There were no complications during the procedure. As a routine imaging exam after ablation, control esophagogastroduodenoscopy was requested to verify that there was no formation of atrio-esophageal fistula developed by the invasive ablation procedure and electrocardiogram, which showed normal sinus rhythm. The patient remained in the cardiac intensive care unit for observation for 24 hours. After the electrical cardioversion and catheter ablation procedures, the patient improved his clinical picture of atrial fibrillation and was discharged after 24 hours of hospitalization. He received treatment to perform at home, to reduce acid reflux into the esophagus and to prevent thrombosis. He did not present pulmonary thromboembolism after hospital discharge. It is believed, therefore, that this form of treatment and management of paroxysmal atrial fibrillation is effective for the solution of the proposed problem and can also serve as a reference for other professionals within the cardiology service.

Anderson-Fabry disease presenting with atrial fibrillation as earlier sign in a young patient:A case report

BACKGROUND Anderson-Fabry disease(AFD)is an X-linked lysosomal storage disorder that results from a deficiency ofα-galactosidase A enzyme activity in which glycosphingolipids gradually accumulate in multi-organ systems.Cardiac manifestations are the leading cause of mortality in patients with AFD.Among them,arrhythmias comprise a large portion of the heart disease cases in AFD,most of which are characterized by conduction disorders.However,atrial fibrillation as a presenting sign at the young age group diagnosed with AFD is uncommon.CASE SUMMARY We report a case of a 26-year-old man who was admitted with chest discomfort.Left ventricular hypertrophy was fulfilled in the criteria by the Sokolow-Lyon index and atrial fibrillation on the 12 Leads-electrocardiography(ECG)that was documented in the emergency room.After spontaneously restored to normal sinus rhythm,relationships between P and R waves,including a shorter PR interval on the ECG,were revealed.The echocardiographic findings showed thickened interventricular septal and left posterior ventricular walls.Based on the clues mentioned earlier,we realized the possibility of AFD.Additionally,we noticed the associated symptoms and signs,including bilateral mild hearing loss,neuropathic pain,anhidrosis,and angiokeratoma on the trunk and hands.He was finally diagnosed with classical AFD,which was confirmed by the gene mutation and abnormal enzyme activity ofα-galactosidase A.CONCLUSION This case is a rare case of AFD as a presentation with atrial fibrillation at a young age.Confirming the relationship between P and Q waves on the ECG through sinus rhythm conversion may help in differential diagnosis of the cause of atrial fibrillation and hypertrophic myocardium.

Contemporary therapy of atrial fibrillation

Atrial fibrillation (AF) is estimated that by 2010, approximately 2.6 million people will be affected in USA;by 2050, that number may increase to 10 million patients. Generally, rate control alone is reasonable in some AF patients, especially asymptomatic patients. Restoration and maintenance of sinus rhythm (SR) may be achieved by means of cardioversion, drugs or/ and catheter ablation. Pharmacological therapy can be useful to maintain SR and prevent tachycardia-induced cardiomyopathy. All patients with AF regardless of whether a rhythm or rate control strategy recommend anticoagulant, antiplatelet or both combined therapy for prevention of thromboembolism, except those with lone AF or contraindications. Drug selection should be based upon the absolute risk of stroke, bleeding, the relative risk and benefit for a given patient. Biventricular pacing may overcome many of the adverse hemodynamic effects associated with RV pacing alone. A target individual ectopic foci ablation within the pulmonary vein (PV) has evolved to circumferential electrical isolation of the entire PV musculature. Cavotricuspid isthmus should be considered as first-line therapy for patients with typical atrial flutter. Completely non-fluoroscopic ablation guided by Real-Time Magnetic Resonance Imaging (RTMRI) using a steerable and non-ferromagnetic catheter is a promising novel technology in interventional electrophysiology.

Case report on the treatment of atrial fibrillation in a pregnant woman of 33 weeks’ gestation

This case report highlights a recent case in the Rotunda Hospital of a patient of 33 weeks’ gestation with fast atrial fibrillation. She had an unusual presentation given that she had no prior cardiac history or obvious aetiology. She underwent successful DC cardioversion and was well on discharge. Follow-up with cardiology has been arranged.