A 'concealed' accessory pathway was suspected in 12 patients because of eccentric left atrial activation during tachycardia. Retrograde conduction during ventricular pacing may occur over the atrioventricular node, the accessory pathway, or both. There were 4 patterns of ventriculoatrial conduction in response to ventricular extrastimuli (V2) at various coupling intervals: (1) exclusive accesso...

The chronological succession of discoveries on the location and structure of the atrio-ventricular conducting system are described. The starting point of this system is located in the sinus atrial node, identified by the English scientists A. Keith and M. W. Flack in 1907. The atrioventricular conducting system was pointed out by the Swiss physician Wilhelm His Jr. in 1893. The atrioventricular...

The electrical consequences of heart failure and their impact on disease progression have frequently been underestimated. It is long known that a significant per cent of heart failure patients develop disease of the conduction system and atrial fibrillation (AF). Conduction disturbances are not only a marker of disease progression but may lead to further haemodynamic deterioration, thus represe...

OBJECTIVES The purpose of this study is to validate the use of tissue Doppler acceleration imaging (TDAI) for evaluation of the onset of ventricular contraction in humans. BACKGROUND Tissue Doppler acceleration imaging can display the distribution, direction and value of ventricular acceleration responses to myocardial contraction and electrical excitation. METHODS Twenty normal volunteers ...

Practolol (I.C.I. 50172) was used to treat supraventricular dysrhythmias in 32 patients with a rapid ventricular rate and with heart disease of varied aetiology. In 26 patients the average reduction in ventricular rate was 75 per minute, while immediate reversion to sinus rhythm occurred in three patients. The slowing effect was mainly due to a direct action on the atrioventricular node. The ef...

Ictal asystole due to sinus node suppression is a cause of sudden unexplained death in epilepsy. Here, for the first time, we describe a complete atrioventricular nodal block in a patient with non-compressive traumatic subdural hematoma, who developed ictal asystole as a delayed presentation. A leadless VVI pacemaker (ventricular paced, ventricular sensed, and pacing inhibited in response to a ...

An otherwise symptom free and healthy patient presented with new onset AV block III. Computer tomography revealed an aneurysm of the right ventricular inflow tract with compression of the AV node. Surgical excision and repair with a patch was performed.

Ventricular tachycardia like ventricular parasystole is rarely observed in the absence of cardiac disease (Massie and Walsh, 1960; Scherf and Bornemann, 1961), though several cases of functional ventricular tachycardia without demonstrable heart disease have been reported by Hair, Eagan, and Orgain (1962) and others. Parasystole consists of simultaneous activity of two independent impulse-formi...

The electrocardiographic term 'pause' refers to the prolonged R-R interval that represents the interruption in ventricular depolarisation. This article presents a case of sinus node dysfunction and provides a diagnostic approach to pauses on the ECG.

OBJECTIVE To review the diagnosis and management of cardiac arrhythmias in a two-part presentation. DATA SOURCES Articles and published peer-review abstracts on tachycardias and bradycardias. SUMMARY OF REVIEW Normal cardiac rhythm originates from impulses generated within the sinus node. These impulses are conducted to the atrioventricular node where they are delayed before they are distri...