ance of pacemakers in Britain a survey was carried out in cooperation between the Institute of Cardiology, the Ministry of Health, and the agents for all types of pacemakers available. The survey was retrospective and covered every pacemaker sold in Britain between 1 April 1965 and 31 March 1966 inclusive. The type of pacemaker, serial number, date of dispatch, and hospital to which the pacemak...

We report a case of electrocautery-induced pacemaker failure that resulted in asystole in a 15-year-old girl scheduled for cardiac surgery. Her pacemaker was converted to the asynchronous mode the night before surgery. Electromagnetic interference from the unipolar electrocautery caused a reduction in the battery voltage, which allowed the digital circuitry, but not the voltage control oscillat...

BACKGROUND The aim of this study was to evaluate the reliability of pacemaker diagnostic function in diagnosing ventricular arrhythmias. METHODS We compared the occurrence of ventricular ectopic beats in 51 simultaneous 24-hour electrocardiogram (ECG) recordings and pacemaker event counters printouts. The diagnostic function of a pacemaker allowed also for a qualitative assessment in 38 patie...

Accurate knowledge ofpacemaker specifications provides the key to the understanding of complex demand pacemaker arrhythmias. This communication describes two examples of complex pacemaker arrhythmias related to the sensing mechanism of normally functioning Medtronic demand pulse generators. Oversensing of atrial voltage generated by an atrial parasystolic focus produced the first arrhythmia. Th...

The implantation of cardiac pacemakers has become a well-established therapy for conduction disorders and sinus node dysfunction. In many countries pacemaker registries have been initiated in order to collect information on patient characteristics, trends in numbers and the types of pacemakers used, to identify problematic devices, and for safety monitoring. For this utilisation study the Centr...

In our attempts to understand the circadian system, we unavoidably rely on abstractions. Instead of describing the behavior of the circadian system in all its complexity, we try to derive basic features from which we form a global concept on how the system works. Such a basic concept is a model of reality. The author discusses why it is advantageous or even necessary to transform conceptual mod...

The aims of this study were to determine the prevalence of severe cardiac conduction disturbances in a cohort of 451 patients with hypertrophic cardiomyopathy and to describe the characteristics of, and outcomes in, those who required a permanent pacemaker. A pacemaker was implanted in 48 patients (11%): 20 had sinus node dysfunction and 28 had an atrioventricular conduction disturbance. Primar...

We report the occurrence of a triboelectric phenomenon (static electricity) that mimicked malfunction of a contemporary pacemaker by creating an electrocardiograpic artifact virtually identical to the pacemaker stimuli. The diagnosis was established by observing a subtle overshoot of the questionable deflection that was absent from pacemaker stimuli.

Electric pacemaker activity drives peristaltic and segmental contractions in the gastrointestinal tract. Interstitial cells of Cajal (ICC) are responsible for spontaneous pacemaker activity. ICC remain rhythmic in culture and generate voltage-independent inward currents via a nonselective cation conductance. Ca(2+) release from endoplasmic reticulum and uptake by mitochondria initiates pacemake...

Our patient had recurrent syncope due to ventricular tachycardia (VT) after one year of VVI Pacemaker implantation. He had pacemaker pocket infection for which new pacemaker was implanted on opposite side but old lead was not explanted completely. Flouroscopy showed redundant loop of old lead in right ventricular inflow which was snared out subsequently. He never had syncope or VT after that.