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R Arzbaecher

Publications and source records attributed to R Arzbaecher.

28 records · Page 2Linked to original sources
PubMed1986

A single atrial extrastimulus can distinguish sinus tachycardia from 1:1 paroxysmal tachycardia.

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 response is expected to appear early as well, but in pace-terminable tachycardias, such as AV reentrant and ventricular with VA conduction, the ventricular rhythm will be unperturbed. Testing of the algorithm was performed in 34 patients. In 29 patients, atrial extrastimuli were delivered during sinus tachycardia, and in 22 patients during various types of 1:1 paroxysmal tachycardia. In one patient the procedure was completely automated, i.e., delivery of the atrial extrastimuli and diagnosis were microcomputer controlled. In 28/29 cases, the delivery of an atrial extrastimulus 80 to 120 ms early during sinus tachycardia elicited a ventricular response at least 28 ms early. In 22/22 patients with 1:1 paroxysmal tachycardia, atrial extrastimuli 80 to 120 ms early failed to produce a significant change in ventricular cycle length. This technique appears to be promising for prevention of inadvertent pacing of sinus tachycardia in an antitachycardia pacemaker.

Diagnosis, Computer-Assisted↗
PubMed1984

Automatic tachycardia recognition.

A microcomputer algorithm for tachycardia identification, suitable for use in an implanted antitachycardia pacemaker, is described. The system employs an atrial and ventricular electrogram, detects a sustained fast rate in either chamber, and awakens the main program to perform detailed analysis of the tachycardia and its immediately preceding beats. The algorithm distinguishes atrial, ventricular, and AV nodal and re-entrant tachycardia from high rates due to sinus tachycardia. For testing of the program, we used a data base of twenty-two tape-recorded and documented arrhythmias provoked during electrophysiologic studies in which atrial and ventricular bipolar electrodes were in place; twenty-one were successfully detected. These included atrial fibrillation, atrial flutter, atrial tachycardia, AV nodal re-entrant tachycardia, AV re-entrant tachycardia using an accessory pathway, and ventricular tachycardia with and without ventriculo-atrial conduction.

Atrial Fibrillation↗
PubMed1984

Tachycardia detection in implantable antitachycardia devices.

We have developed a microcomputer algorithm for tachycardia identification suitable for use in an implanted antitachycardia pacemaker. The algorithm distinguishes atrial, ventricular, and AV reentrant tachycardia, while ignoring high rates due to sinus tachycardia. A new method whereby the pacemaker delivers an atrial extrastimulus has been developed for distinguishing paroxysmal 1:1 tachycardia from sinus tachycardia, and has undergone preliminary testing in the electrophysiology laboratory. Preliminary results indicate sinus tachycardia can be reliably distinguished from paroxysmal 1:1 tachycardia by a properly timed extrastimulus delivered to the right atrium.

Cardiac Pacing, Artificial↗
PubMed1976

A quantitative description of normal AV nodal conduction curve in man.

The AV nodal conduction curve generated by the atrial extrastimulus technique has been described only qualitatively in man, making clinical comparison of known normal curves with those of suspected AV nodal dysfunction difficult. Also, the effects of physiological and pharmacological interventions have not been quantifiable. In 50 patients with normal AV conduction as defined by normal AH (less than 130 ms), normal AV nodal effective and functional refractory periods (less than 380 and less than 500 ms), and absence of demonstrable dual AV nodal pathways, we found that conduction curves (at sinus rhythm or longest paced cycle length) can be described by an exponential equation of the form delta = Ae-Bx. In this equation, delta is the increase in AV nodal conduction time of an extrastimulus compared to that of a regular beat and x is extrastimulus interval. The natural logarithm of this equation is linear in the semilogarithmic plane, thus permitting the constants A and B to be easily determined by a least-squares regression analysis with a hand calculator.

Adult↗
PubMedDate not supplied

A pill electrode for the study of cardiac arrhythmia.

A swallowable electrode has been developed which permits accurate P wave detection without patient risk or discomfort. This esophageal lead, together with a simultaneous surface ECG, is the basis for a new two-channel computer system for arrhythmia detection and analysis.

Arrhythmias, Cardiac↗