Atrial fibrillation (AF) is an extremely common cardiac rhythm disorder that causes substantial morbidity and contributes to mortality. The mechanisms underlying AF are complex, involving both increased spontaneous ectopic firing of atrial cells and impulse reentry through atrial tissue. Over the past ten years, there has been enormous progress in understanding the underlying molecular pathobio...

INTRODUCTION Atrial fibrillation was previously reported in patients with esophageal cancer as a complication of total esophagectomy or photodynamic therapy. Here, we propose that atrial fibrillation may also be caused by external compression of the left atrium by esophageal cancer. CASE PRESENTATION We present a 58-year-old man who developed atrial fibrillation with rapid ventricular rate in...

Pervenous electrical stimulation of the right atrium was successful in converting 15 episodes of supraventricular tachyarrhythmia in 9 of 15 patients. This included 13 conversions of atrial flutter, one each of atrial tachycardia and junctional tachycardia. The procedure was performed at the bedside, without complication', using intracardiac electrography to direct catheter position. Indirect e...

BACKGROUND The left atrial posterior wall (LAPW) is potentially an important area for the development and maintenance of atrial fibrillation. We assessed whether there are regional electrical differences throughout the murine left atrial myocardium that could underlie regional differences in arrhythmia susceptibility. METHODS We used high-resolution optical mapping and sharp microelectrode re...

BACKGROUND Successful ablation of ectopic beats originating from the pulmonary veins (PV) could eliminate paroxysmal atrial fibrillation (PAF). However, information about the structure of the PV in patients with PAF that is initiated by PV ectopic beats has not been reported. METHODS AND RESULTS We studied the morphology of the PVs and measured their diameters in 3 groups of patients. Group I...

The antiarrhythmic effect of the cardioselective beta-adrenoceptor blocking agent metoprolol, given intravenously, was studied in 44 patients with various tachyarrhythmias, including patients with congestive heart failure and signs of digitalis intoxication. All patients with atrial tachycardia (12 cases) reverted to normal sinus rhythm. In 3 out of 18 patients with atrial fibrillation, sinus r...

BACKGROUND The superior vena cava (SVC) has cardiac musculature extending from the right atrium. However, no previous study in humans has given details regarding the ectopic foci that initiate paroxysmal atrial fibrillation (PAF), which may originate from the SVC. METHODS AND RESULTS A total of 130 patients with frequent attacks of PAF initiated by ectopic beats were included. Eight patients ...

BACKGROUND Prediction of stroke and atrial fibrillation in healthy individuals is challenging. We examined whether excessive supraventricular ectopic activity (ESVEA) correlates with risk of stroke, death, and atrial fibrillation in subjects without previous stroke or heart disease. METHODS AND RESULTS The population-based cohort of the Copenhagen Holter Study, consisting of 678 healthy men a...

BACKGROUND The morphology and polarity of the P wave on 12-lead ECG are of limited clinical value in localizing ectopic atrial rhythms. It was the aim of this study to assess the spatial resolution of body surface P-wave integral mapping in identifying the site of origin of ectopic right atrial (RA) impulse formation in patients without structural atrial disease. METHODS AND RESULTS Sixty-two...

The effects of intravenous diphenylhydantoin (5 mg/kg) on atrioventricular conduction in man at controlled heart rates in the digitalized and undigitalized state were studied. In undigitalized subjects, diphenylhydantoin administration consistently decreased A-V conduction time in each individual subject when identical heart rates were compared. Ouabain infusion produced an increase in A-V cond...