Atrial fibrillation (AF) is a complex arrhythmia with multiple possible mechanisms. It requires a trigger for initiation and a favorable substrate for maintenance. Pulmonary vein myocardial sleeves have the potential to generate spontaneous activity, and this arrhythmogenic activity is surfaced by modulation of intracellular calcium dynamics. Direct autonomic nerve recordings in canine models s...

BackgroundValvular heart disease is one of the common complications of acute rheumatic fever, which manifests its clinical complications one or two decades after the primary attack of the disease in adults. The disease may involve one or more valves as stenosis or regurgitation or both and may cause congestive heart failure due to chronic volume or pressure overload. MethodThis prospective stud...

Atrial fibrillation can be triggered by rapid atrial rhythms, including intranodal tachycardia. We present the recordings of a male patient with paroxysmal atrial fibrillation referred for pulmonary vein ablation following failure of various antiarrhythmic drug treatments (bisoprolol, flecainide, and amiodarone). The initial study showed two QRS complexes with a single p wave. A double nodal pa...

This study aimed to evaluate the relationship between serum transforming growth factor-β1 (TGF-β1) concentration and atrial fibrosis and to determine whether plasma TGF-β1 concentration is an independent predictor of atrial fibrillation (AF) recurrence after catheter ablation.We included 98 consecutive patients who underwent catheter ablation, including 38 with paroxysmal AF (AF group) and 60 w...

Introduction Pulmonary vein isolation (PVI) remains the cornerstone of therapy for patients with drug-refractory paroxysmal atrial fibrillation; and recent studies have suggested that even for patients with persistent atrial fibrillation, addition of linear lesions to PVI may not confer any advantage in efficacy. Despite this, patients with significant left atrial fibrosis and chamber enlargeme...

One of the most exciting developments in our understanding of atrial fibrillation (AF) over the last several years has been the recognition that AF itself modifies atrial electrical properties in a way that promotes the occurrence and maintenance of the arrhythmia, a process termed 'atrial remodeling'. The principle stimulus for AF-induced atrial remodeling is the rapid atrial rate that results...

QUESTIONS Atrial ectopic tachycardia (AET) may be difficult to diagnose in neonates and treatment can be complex especially in case of severe heart failure. This study addresses the clinical recognition and drug therapy of AET in neonates. METHODS Retrospective chart and database review of neonates diagnosed with AET between 1994 and 2002. RESULTS AET was diagnosed in 19 neonates at a media...

Paroxysmal supraventricular tachycardia most commonly arises from reentry within the atrioventricular (AV) node. Although ablation of the His bundle has gained popularity for treating patients with AV node reentrant tachycardia refractory to medical therapy, undesirable sequelae include complete heart block and the necessity for a permanent pacemaker. To obviate this limitation, we have develop...