Clinical Experience in Transvenous and Myocardial Pacing

Abstract

Long-term cardiac stimulation with implantable pacemakers has become a widely accepted method for the treatment of heart block. Cardiac pacing is the most effective means of preventing Adams-Stokes attacks. Senningll was the first, in 1958, to implant an electrical pacemaker. Since that time, many improvements have been made, as much with regard to the reliability of pulse generators as to the techniques of implantation. Endocardia1 pacing, introduced in 1958 as a temporary method,' has gained now wide acceptance for long-term treatment.Since 1962, our group has taken interest in the pacemaker treatment of heart block. To date, 372 patients have been treated at the Cantini Cardiologic Center. Epicardial stimulation, used at the beginning of our studies, has progressively given way to endocardial pacing, which is now almost exclusively used. The new methods of stimulation (atrial-triggered, ventricular-triggered, demand) have been tested under clinical conditions. The present report sums up our results and conclusions based on six years of experience. Patient Population MATERIAL AND METHODSThe 372 patients in this study were from 13 to 93 years of age (FIGURE 1 ) . There were 233 men and 139 women in the group; 54.5% were over 70 years old when the implantation procedure was performed, and 12.6% were over 80. Indications for cardiac pacing were: ( 1 ) syncopal attacks, (2) cardiac failure related to bradycardia, and (3) excessive bradycardia (under 30 beats per minute), causing important reduction of physical activity.Most patients had chronic idiopathic heart block. Three of them required pacing for isolated congenital heart block, with occurrence of syncopal attacks uncontrolled by medical treatment. In two cases, a pacemaker was implanted for bradycardia unrelated to atrioventricular conduction disturbance: In the first case, there was a sinus bradycardia with bigeminal rhythm; the second patient displayed auricular standstill. Both patients experienced losses of consciousness. Pacemakers UsedThe first group of patients includes 74 subjects in whom the electrodes were implanted by thoracotomy. The second consists of 298 patients treated by endocardial stimulation. Twenty-one additional patients from the first group were subsequently paced by the pervenws technique, following failure of epicardial pacing due to fracture or displacement of the electrode or infection requiring complete removal of the whole apparatus. Several types of pulse generators have been used in each group: fixed-rate, adjustable-rate, dual-rate, atrial-triggered, ventricular-triggered, and demand (TABLE 1 ). Implantation ProcedureEpicardial electrodes were inserted according the classical technique. The chest was entered through the fifth intercostal space. Disk electrodes (Elema) were fixed in such a manner that good contact could be ensured. Two additional 995

Recurrent Endocarditis in a Patient with a Permanent Transvenous Pacemaker

“…Staphylococcus epidermidis was the most common organism overall, but Staphylococcus aureus predominated in the early onset group. In patients with septicemia, mortality ranged from 0 to 50% [4,[10][11][12].…”