Termination of acute wide QRS complex atrial fibrillation with ibutilide

Ibutilide is a Vaughan-Williams class III antiarrhythmic agent approved for chemical cardioversion of acute onset atrial fibrillation/flutter. Emergency physicians rarely use ibutilide despite its proven clinical value. We report a case of successful chemical cardioversion using ibutilide in a patient with atrial fibrillation and delayed ventricular depolarization (wide QRS complex). We recommend that ibutilide be considered for wider use in the emergency department and that further studies be conducted.     

Postoperative atrial fibrillation

Atrial fibrillation is a common arrhythmia after cardiac surgery. It is associated with an increase in morbidity, length of hospital stay, and mortality. Patients who are at higher risk of postoperative atrial fibrillation should receive prophylactic treatment. Atrial fibrillation usually resolves spontaneously after heart rate is controlled; however, if patients are highly symptomatic or hemodynamically unstable, sinus rhythm should be restored by electrical or pharmacologic cardioversion. Patients with atrial fibrillation of more than 48 hours should receive antithrombotic therapy for thromboembolism prevention.     

Ganglionated plexi ablation directed by high-frequency stimulation and complex fractionated atrial electrograms for paroxysmal atrial fibrillation

Background: The effectiveness of ganglionated plexi (GP) ablation in patients with atrial fibrillation (AF) is ambiguous. Some researchers had already suggested that additional identification of complex fractionated atrial electrograms (CFAE) around the areas with a positive reaction to high‐frequency stimulation (HFS) might improve the accuracy of GP's boundaries location, then enhancing the success rate of ablation. The purpose of this study was to assess the safety and efficacy of GP ablation directed by HFS and CFAE in patients with paroxysmal AF (PAF). Methods and Results: Sixty‐two patients with PAF (age 57±8 years) underwent GP ablation. Ablation targets were the sites where vagal reflexes were evoked by HFS and additional extended ablation CFAE area around the areas where vagal reflexes were evoked. At 12 months, 71% of patients were free of symptomatic AF. At 3 months after ablation the root mean square successive differences and HF were significantly lower in patients without AF recurrence (P < 0.0001 and P = 0.004). The LF/HF ratio was significantly higher in patients without AF recurrence (P = 0.02). Conclusion: Enhanced GP ablation directed by HFS and CFAE can be safely performed and enables maintenance of sinus rhythm in the majority of patients with PAF for a 12‐month period. Denervation of the intrinsic cardiac autonomic nervous system may be the preferable target of catheter ablation of AF. (PACE 2012;XX:1–9)     

Persistent atrial fibrillation vs paroxysmal atrial fibrillation: differences in management

Introduction: Atrial fibrillation (AF) is the most common human arrhythmia. AF is a progressive disease, initially being nonsustained and induced by trigger activity, and progressing towards persistent AF through alteration of the atrial myocardial substrate. Treatment of AF aims to decrease the risk of stroke and improve the quality of life, by preventing recurrences (rhythm control) or controlling the heart rate during AF (rate control). In the last 20 years, catheter-based and, less frequently, surgical and hybrid ablation techniques have proven more successful compared with drug therapy in achieving rhythm control in patients with AF. However, the efficiency of ablation techniques varies greatly, being highest in paroxysmal and lowest in long-term persistent AF.

Areas covered: In this review, we discuss the fundamental differences between paroxysmal and persistent AF and the potential impact of those differences on patient management, emphasizing the available therapeutic strategies to achieve rhythm control.

Expert commentary: Treatment to prevent AF recurrences is suboptimal, particularly in patients with persistent AF. Emerging technologies, such as documentation of atrial fibrosis using magnetic resonance imaging and documentation of electrical substrate using advanced electrocardiographic imaging techniques are likely to provide valuable insights about patient-specific tailoring of treatments.     

Deglutition induced atrial tachycardia and atrial fibrillation

Deglutition induced supraventricular tachycardia is an uncommon condition postulated to be a vagally mediated phenomenon due to mechanical stimulation. Patients usually present with mild symptoms or may have severe debilitating symptoms. Treatment with Class I agents, beta blockers, calcium channel blockers, amiodarone and radiofrquency catheter ablation has shown to be successful in the majority of reported cases. We report the case of a 46-year-old healthy woman presenting with palpitations on swallowing that was documented to be transient atrial tachycardia with aberrant ventricular conduction as well as transient atrial fibrillation. She was successfully treated with propafenone with no induction of swallowing-induced tachycardia after treatment. This is also the first case to show swallowing-induced atrial tachycardia and atrial fibrillation in the same patient.     

The atrial electrical remodeling in atrial fibrillation

The electrical remodeling in atrial fibrillation is defined as the shortening of the atrial effective refractoriness, the loss of its late dependency and the slowing of conduction velocity caused by rapid excitation of the atrial muscle. Although, this phenomenon may play an important role in promoting the appearance of the reentrant atrial fibrillation by shortening the wavelength, the clinical aim and importance of controlling the electrical remodeling are still unclear. Ca channel or Na channel blockers may reduce the electrical remodeling in relatively short-term by preventing the elevation of intracellular Ca concentration, though, the long-term effect is unknown.     

Anticoagulation in atrial fibrillation

In this overview the actual guideline-recommendations for anticoagulation in atrial fibrillation and the problems of the currently available therapy are discussed. Furthermore an outlook over future developments in this field is given. Effective anticoagulation can prohibit thrombembolic events and is thus essential for the prognosis of patients suffering from atrial fibrillation. Until now vitamin-K-antagonists (VKAs) and acetylsalicylic acid (ASA) are available for oral anticoagulation in these patients. VKAs demonstrate a satisfying efficiency combined with rather high bleeding hazard. ASA on the other hand allows only moderate risk reduction with minimal side effects. Thus the guidelines recommend anticoagulation tailored to the individual risk, which can be evaluated by the CHADS2-Score. New therapeutic strategies, like the factor Xa inhibitor rivaroxaban or the factor II inhibitor dabigatran, are actually evaluated in phase III studies. These drugs bear the hope of higher efficiency combined with improved safety and much more comfortable use in the daily practice (e. g. no need for INR measurement, no dose adaptation).     

Steroid induced atrial fibrillation

A 72-year-old female presented with an acute flaure of Crohn's disease and received intravenous methylprednisolone. The following morning ECG showed atrial fibrillation with a rapid ventricular response of 111 bts/min, which spontaneously resolved within 7 hours. The underlying arrhythmogenenic mechanism is unknown.     

Controlling persistent atrial fibrillation

Sir, The recent review of rate or rhythm control in persistent atrialfibrillation by Boos and colleagues¹ favours a rate controlstrategy in patients with NYHA > II symptoms or LVEF <40%. However, there is     

Lifestyle and atrial fibrillation

Lifestyle factors, in particular dietary intake, have been recognized as important, modifiable risk factors for cardiovascular disease. Consuming a heart-healthy diet lowers the individual's risk for cardiovascular disease. Data on the relationship between lifestyle and atrial fibrillation are controversial; however, the strong association between obesity, atrial/ventricular dysfunction and a nonhealthy lifestyle and atrial fibrillation, suggests that a correction of nutritional habits could prevent the development of arrhythmias through a reduction of underlying cardiac diseases. Today, the Mediterranean diet is considered one of the most effective in terms of its prevention of cardiovascular disease.     

Management of atrial fibrillation

Atrial fibrillation (AF) is one of the most common arrhythmias encountered in the adult population. It can be an isolated event or a chronic lifelong rhythm disturbance. The common causes of AF and the presenting electrocardiogram characteristics are outlined. The risks to the patient in AF, the role of the nurse, and treatment options are also discussed.     

Paroxysmal atrial fibrillation.

There has been a tendency to treat paroxysmal atrial fibrillation (PAF) in a similar way to sustained AF, but treatment objectives may be very different. We discuss current definitions, epidemiology, pathophysiology and natural history of PAF, and review evidence for its treatment and management. PAF comprises between 25% and 62% of cases of AF, with similar underlying causes to those in sustained AF. The main objective of management is prevention of paroxysms and long-term maintenance of sinus rhythm, and Class 1c drugs are highly effective, although beta-blockers are useful alternatives. If patients have severe coronary artery disease or poor ventricular function, amiodarone is probably the drug of choice. Although randomized controlled trials of thromboprophylaxis in patients with paroxysmal AF per se are lacking, the approach to patients with paroxysmal AF should be similar to that in patients with sustained AF, with warfarin for 'high risk' patients and aspirin for those at 'low risk'. Non-pharmacological therapeutic options, including pacemakers, electrophysiological techniques and the implantable atrial defibrillator, show great promise. Despite paroxysmal AF being a common condition, management strategies are limited by evidence from small randomized trials, with inconsistencies over the definition of the arrhythmia and the inclusion of only symptomatic subjects. Evidence for antithrombotic therapy is also based on epidemiological studies and subgroup analyses of the large randomized trials.     

Surgery for atrial fibrillation

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ATRIAL FIBRILLATION (AF) is the most common sustained disturbance of cardiac rhythm, affecting an estimated 2.3 million people in North America and 4.5 million people in the European Union.

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ALTHOUGH AF IS ASSOCIATED with significant morbidity, mortality, and increased health care costs, more-precise and less-invasive surgical ablation procedures have been developed. Specific cardiac sites emitting the aberrant, premature electrical signals that induce AF are ablated, which results in excellent cure rates and allows normal sinus rhythm to resume.

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THESE PROCEDURES can be performed with or without the use of cardiopulmonary bypass, through either traditional sternotomy or minimally invasive thoracotomy incisions. AORN J 86 (July 2007) 23-40. © AORN, Inc, 2007.