was initially decided to induce atrial fibrillation as necessary with the use of a permanent radiofrequency-controlled atrial pacemaker. Several days after implantation of the pacemaker, however, rapid atrial pacing produced atrial tachycardia with atrioventricular block rather than atrial fibrillation. Despite this apparent failure, the ventricular rate has been adequately controlled by rapid ...

The effect of electrically induced auricular and ventricular tachycardia of various rates was studied in the anesthetized dog. When, the control heart ranging between 140 and 190 per minute, atrial tachycardia of a rate only slightly higher than the control rate was induced, a very temporary initial decrease in arterial blood pressure, cardiac output and coronary blood flow occurred, then all t...

Atrioventricular (A-V) conduction, ventriculo-atrial conduction and mechanism of tachycardia were studied by programmed electrical stimulation before and after the administration of ouabain in 15 patients suffering from paroxysmal supraventricular re-entrant tachycardia. In 13 patients the tachycardia circuit was confined to the A-V node. In two patients the stimulation study showed that an acc...

Two neonates with rapid and irregular pulse rate had an uncommon form of atrial tachycardia. The irregular heart rate was first detected during fetal monitoring. Postnatal electrocardiograms were compatible with the diagnosis of multifocal atrial tachycardia or chaotic atrial rhythm. Both patients were treated with digoxin and the rhythm gradually reverted to sinus. This may represent the first...

We present a case of a 37-year-old female who complained of frequent palpitations caused by an atrial tachycardia and atrial premature contractions. Angiography revealed that the coronary sinus was occluded at the ostium and connected to a persistent left superior vena cava. An electrophysiological study and three-dimensional mapping revealed that the origin of the atrial tachycardia and atrial...

Sofosbuvir is an antiviral drug that entirely revolutionized the treatment of hepatitis C. This drug has an Iranian commercial brand, which is known as Ledibiox. Several adverse events have been reported with this drug, including syncope, pancolitis, and exacerbated pulmonary arterial hypertension; however, arrhythmia rarely has been described through the literature. Here, we report a 40-year-o...

Conversion of the atriopulmonary Fontan to a total cavopulmonary extracardiac connection with concomitant arrhythmia surgery and pacemaker placement is a safe and efficacious procedure for this patient population. From 1994 to 2007 a total of 118 patients have undergone this procedure with one (0.8%) early and nine (7.6%) late deaths. During the course of our experience with Fontan conversion o...

Whether or not the atrium plays an essential role in initiating and/or sustaining atrioventricular (A-V) nodal re-entrant tachycardia was evaluated in eight patients. In all eight patients, the atrium could be rendered refractory to retrograde atrial echoes during the tachycardia without interrupting the arrhythmia. This was accomplished by introducing atrial premature depolarizations prior to ...

We have developed a tachycardia detection scheme for use in an antitachycardia pacemaker in which the use of a properly timed atrial extrastimulus provides a means of discriminating sinus tachycardia from pace-terminable 1:1 tachycardias. An atrial extrastimulus is delivered in late diastole (80 ms premature), and the ventricular response is monitored. In sinus tachycardia, the ventricular resp...

A new neural network system for classification of the cardiac rhythm is presented in this paper. The system is composed of two neural network classifiers : a morphological classifier cascaded to a timing classifier. While the morphological classifier classify the P and QRS complexes into normal and/or abnormal beats, the timing classifier takes as inputs the information of the morphological cla...