INTRODUCTION The cardiovascular consequences related to amyotrophic lateral sclerosis are relatively underappreciated. The disease invokes a systematic degeneration of autonomic neurons leading to autonomic dysfunction. We therefore hypothesized that patients with amyotrophic lateral sclerosis may have a predilection to the development of cardiac conduction disorders. CASE PRESENTATION A 65-y...

The electrocardiogram (ECG) characteristics of athletes have recently become a topic of intensive study to accurately identify dangerous and benign alterations in this special population. These subjects develop a high-vagal tone and consequently sinus bradycardia and different degrees of atrioventricular (AV)-block, but it is difficult to determine how much is too much, and the indications for ...

The underlying mechanism of bradycardia-dependent bundle-branch and paroxysmal atrioventricular block appears to be enhancement of phase-4 depolarization in a branch or in a natural or acquired monofascicular pathway. Clinical records of these forms of impaired conduction occurring in the bundle-branches, with either longer or shorter cardiac cycle lengths, are presented and analysed. These als...

This report describes 16 patients with block within the His bundle seen over a period of 55 months. Ten were women and 6 men, with an average age of 76 years, range, 42 to 98 years. All patients had His bundle recordings showing split His bundle potentials (H and H) (13 patients) or narrow QRS with block distal to the His bundle potential (3 patients). Of the 16 patients, 10 had complete heart ...

INCOMPLETE TRANSMISSION of impulses across the atrioventricular (A-V) junction has held a special fascination for many investigators.'14 Varied investigational techniques including venous pulse waves, standard electrocardiograms, and direct catheter electrode recordings from the cardiac chambers have been used to further the understanding of retrograde transmission of impulses into the A-V junc...

The introduction of the artificial electrical pacemaker for the treatment of patients with complete A-V block has been accompanied by renewed interest in the pathogenesis of this disorder. It has been considered that most cases of complete block are due to organic or functional lesions either in the A-V node or in the common A-V bundle. Barker and Hirschfelder in 1909 and later Eppinger and Rot...

Atrioventricular conduction was studied in three patients, each representing a different grade of bilateral bundle-branch block. His bundle activity was recorded by a catheter technic. Two of the three patients had experienced Adams-Stokes attacks. The first patient had right bundle-branch block with left axis deviation at the time of catheterization. Increases in the atrial driving rate result...

This report describes the data of the Spanish Registry of Pacemakers, based on the European Pacemaker Identification Card, and the changes in the use of different stimulation modes since 1994. Of note is the significant and steady change towards more physiological modes of stimulation (which maintain atrioventricular synchrony). These modes accounted in 2003 for 69.9% among patients with sick s...

The electrocardiograms of 100 patients with rapid and regular PP intervals during atrial arrhythmias (because of atrial tachycardia or flutter, or pacing) were examined for periods of irregular atrioventricular conduction. This irregular conduction corresponds to an alternating Wenckebach phenomenon, of a type that can be determined from simple rules. The different types of conduction encounter...

Modification of atrioventricular node is a usual and necessary operation to cure atrioventricular nodal reentrant tachycardia (AVNRT). In this operation, atrioventricular block is the most severe complication and its prevention is of our great concern. This complication always occurs under some special circumstances with potential risk. So, it is very important to realize such conditions, as in...