Postablation-acquired short atrioventricular Mahaim-type fibers: observations on their clinical, electrocardiographic, and electrophysiologic profile.

Background: The electrophysiologic characteristics of decrementally conducting accessory pathways (APs) are well described; however, little is known about decrementally conducting APs caused by the radiofrequency ablation of a rapidly conducting AP.

Objective: To report the clinical, electrocardiographic, and electrophysiologic characteristics of 6 patients who developed a decremental AP after an attempt at ablation.

Methods: We compared the clinical and electrophysiologic characteristics of 295 consecutive patients with the Wolff-Parkinson-White syndrome who underwent radiofrequency ablation of 311 manifest APs (group A) with those of 6 patients with the Wolff-Parkinson-White syndrome in whom a decrementally conducting AP was detected after an attempt at ablation.

Clinical, electrocardiographic, and electrophysiologic characteristics of patients with a fasciculoventricular pathway: the role of PRKAG2 mutation.

Background: The ECG, clinical, and electrophysiologic profiles of patients with a fasciculoventricular pathway are well described. Fasciculoventricular pathways occurring in the setting of glycogen storage cardiomyopathy possess unique features.

Objective: The purpose of this study was to compare the clinical, ECG, and electrophysiologic characteristics of patients with a fasciculoventricular pathway, with or without glycogen storage cardiomyopathy.

The atrioventricular interval during pre-excited tachycardia: a simple way to distinguish between decrementally or rapidly conducting accessory pathways.

Background: Recognition of the presence and role of decremental fibers during wide QRS tachycardia requires carefully executed intracardiac studies.

Objective: This study sought to determine the value of the atrioventricular (AV) conduction time during pre-excited tachycardia to differentiate a fast from a decrementally conducting accessory pathway (AP).

Methods: Fifty-one patients with 56 pre-excited tachycardias were included in the study: Group I: 27 patients with 31 antidromic tachycardia (ADT) using an atriofascicular pathway, Group II: 2 patients with pre-excited tachycardia due to bystander AV conduction, Group III: 3 patients with ADT and a short AV Mahaim fiber, and Group IV: 19 patients with 21 ADT using a fast conducting right-sided AP.

Reversible cardiomyopathy provoked by focal ventricular arrhythmia originating from the base of the posterior papillary muscle.

Background: A new distinct clinical syndrome comprising of ventricular tachycardia or frequent premature beats arising from the base of the posterior papillary muscle has recently been reported. The cardiac arrhythmia had a non-reentrant mechanism and none of the patients had left ventricular dysfunction.

Case Report: We report on a 55-year-old female patient presenting with a dilated cardiomyopathy and frequent ventricular premature beats (VPB).

The 12-lead ECG in patients with Mahaim fibers.

The aim of this review article is to discuss the electrocardiographic presentation of the so called variants of pre-excitation ("Mahaim fibers") during sinus rhythm and tachycardia.

[Wolff-Parkinson-White syndrome and the sinus venosus atrial septal defect association].

The Wolff-Parkinson-White syndrome (WPW) and sinus venosus atrial septal defect (ASD) association is very rare and not yet reported in the literature. It is the main basis for this case report.

Radiofrequency catheter ablation of an accessory pathway in a patient with Wolff-Parkinson-White and Kartagener's syndrome.

We report a case of a manifest left free wall accessory pathway in a patient with Kartagener's syndrome and recurrent episodes of orthodromic atrioventricular reentrant tachycardia. To the best of our knowledge, it is the first report of Wolff-Parkinson-White syndrome associated with Kartagener's syndrome. Situs inversus and mirror image dextrocardia occurred with no additional detectable cardiac structural abnormalities.

Fasciculoventricular pathways: clinical and electrophysiologic characteristics of a variant of preexcitation.

Unlabelled: Fasciculoventricular Fibers.

Introduction: Fasciculoventricular tracts are considered a rare form of ventricular preexcitation. Few fasciculoventricular pathways have been reported, and none have been linked to a reentrant tachycardia.

Appraisal of "Mahaim" automatic tachycardia.

A series of four patients with right-sided accessory pathways with long conducting times and decremental properties is reported. All patients underwent radiofrequency catheter ablation, and target areas were guided by a discrete "Mahaim" potential recorded at the lateral aspect of the tricuspid valve. A slow automatic and irregular rhythm with a QRS morphology similar to that of a fully preexcited QRS complex occurred during radiofrequency current delivery.