Telephone monitoring of patients with pacemakers in the west of Scotland.

A regional telephone pacemaker follow-up service has been established in the west of Scotland. Medical care is provided by clinics at district general hospitals in Ayrshire, and the pacemaker signals are transmitted by telephone from these clinics to a pacemaker centre in Glasgow. The success of the pilot project in Ayrshire will allow expansion of the service to include hospitals in other areas of the west of Scotland. The scheme is carefully monitored to ensure that patients with pacemakers receive adequate attention with a minimum of inconvenience.

Screening of solid and porous materials for pacemaker electrodes.

Several different materials, including one which was porous, were studied to assess their properties as pacemaker electrode tips. Leads were implanted in sheep for periods up to one year. Electrical measurements were made during the implant period and histopathological examination performed after sacrifice. Although titanium vapor-deposited carbon, and silver did not lower the chronic stimulation threshold below that of platinum, their electrical characteristics were within generally acceptable limits. Zinc evoked a severe tissue reactions and a high threshold. Porous titanium alloy electrodes demonstrated reduced dislodgement, more frequent attachment and a lower sensing impedance than other electrodes.

[Hemodynamic and exercise capacity in a 72 years old patient under a ventricular and bifocal pacemaker (author's transl)]. / Hämodynamik und körperliche Belastbarkeit bei ventrikelgesteuertem (VVI) and AV-sequentiellem Schrittmacher (DDD) (Falldemonstration).

The results of haemodynamic, echocardiographic and bicycle exercise investigations in a 72-year-old man with a permanent complete atrioventricular block and heart failure following infarction are presented. Comparative measurements were obtained under the conditions of a ventricular and an av-sequential pacemaker (PM). The ventricular demand pacemaker (VVI) was implanted three years ago and because of further impairment of cardiac performance an av-sequential pacemaker (DDD) was used to restore atrio-ventricular synchronisation. The treatment with bifocal PM improved dramatically cardiac output and exercise capacity. The echocardiographic findings demonstrate the significance of Frank-Starling mechanism in this case due to better filling of the ventricles. As noninvasive methods, echocardiography and bicycle-exercise test allow long-term analysis of cardiac function.

Implantation of permanent transvenous atrial J lead using lateral view fluoroscopy.

Fifty consecutive, tined, atrial J leads were implanted for atrial and atrioventricular sequential pacing using lateral view fluoroscopy for atrial lead manipulation and positioning. The technique is described in detail. It is concluded that lateral view fluoroscopy allows a more expeditious and reliable positioning in the right atrial appendage.

Multiprogrammable pacemakers.

Since 1962 it has been possible to change, by noninvasive means, the functions of implanted pacemakers. This study reports a 3-year multicentre experience, in 164 patients, with a multiprogrammable pacemaker that offers a wide range of choices within five variables: mode, rate, pulse width, sensitivity and telemetry (over 3000 combinations). In a selected series 83% of implanted pacemakers were programmed for medical indications and 100% for multiparameter follow-up studies. The advantage and disadvantages of three are compared. There is little doubt that multiprogrammable pacemakers can reduce the frequency of reoperation in any large series.

[Septicemia following infection of an endocardial electrode lead (author's transl)]. / Septicémie secondaire à l'infection d'une sonde de pacemaker endocavitaire.

The authors report one case of septicemia following the infection of a remaining endocardial electrode lead. From this observation and the literature's data, they are thinking that it is essential to remove the entire pacemaker system (electrode lead and generator) to cure this complication. They remind the different technics used to remove the endocardial leads.

Arrhythmia resulting from sensing malfunction in a P wave triggered pacemaker.

P wave triggered pacemakers can produce complicated arrhythmias during normal function. A ventricular, R wave inhibited pacemaker and an atrial sensing pacemaker were both present and functioning normally in the patient reported here. A premature paced beat was observed every 12th beat which resulted from discharge of the atrial sensing pacemaker. This arrhythmia appeared because a "P" wave occurred during the noise sampling period of the atrial sensing pacemaker, disabling the demand function and resulting in generator discharge on or near the T wave of a preceding unsensed beat while the pacemaker was in the asynchronous mode.

Biomedical implantable microelectronics.

Innovative applications of microelectronics in new biomedical implantable instruments offer a singular opportunity for advances in medical research and practice because of two salient factors: (i) beyond all other types of biomedical instruments, implants exploit fully the inherent technical advantages--complex functional capability, high reliability, lower power drain, small size and weight-of microelectronics, and (ii) implants bring microelectronics into intimate association with biological systems. The combination of these two factors enables otherwise impossible new experiments to be conducted and new paostheses developed that will improve the quality of human life.