Studies of the Tissue Reaction Induced by Transvenous Pacemaker Electrodes. I. Microscopic Examination of the Extent of Connective Tissue Around the Electrode Tip in the Human Right Ventricle

Abstract

The purpose of this study was to investigate the extent of connective tissue of the human right ventricle induced by cardiac pacing electrodes. Between January 1984 and July 1987, 34 consecutive patients with VVI-pacing systems were autopsied in the Department of Pathology at the University of Frankfurt/M. The surrounding tissue of these 34 electrodes (17 Siemens Elema 412 S, five Medtronic 6957, one Medtronic 6959, one Medtronic 4011, three Biotronik D2K, three Biotronik K 10, two Osypka FY 62, one Biotronik N, and one Siemens Elema 588) in the right ventricle were investigated histologically. The tissue was stained with Giemsa and the thickness of the connective tissue layer was measured. Stimulation threshold data at various times were known in four of eight screw-in electrodes, in seven of 17 vitreous carbon electrodes and in two of seven smooth surface electrodes. Electrode surface area, implantation time, age of the patient and cause of death were comparable for all three electrode groups. However, a significant difference was found in the extent of connective tissue between the porous surface and screw-in electrodes (128 +/- 55 vs 397 +/- 269 micron, P less than or equal to 0.01) and porous surface and smooth surface electrodes (128 +/- 55 vs 307 +/- 117 micron, P less than or equal to 0.01). No relation (r = 0.106) was found between the duration of implantation and the extent of connective tissue for the vitreous carbon electrodes (Siemens Elema 412 S).(ABSTRACT TRUNCATED AT 250 WORDS)

Biochemical Evidence of Cardiac Damage Following Transvenous Implantation of a Permanent Antibradycardia Pacemaker Lead

“…Transvenous insertion of endocardial leads for permanent pacing is accompanied by acute injury, which is followed by a sequence of cardiac histopathological changes starting with acute inflammation and leading eventually to the formation of fibrous connective tissue scar 16,17 …”

“…The technique of lead fixation in the right atrium did not have an independent effect on peak CTNI levels. Histological studies have shown that the connective tissue reaction around active fixation electrodes is more intense than that around porous surface electrodes 17 . It is possible, however, that the fixation technique is not so important for myocardial damage when the thin‐walled atrial myocardium is concerned.…”

Evaluation of Fractal‐Coated Temporary Pacing Leads in the Early Postoperative Course

“…Development of permanent pacing leads is strongly influenced by the search of the “ideal” electrode. This electrode should offer low and long‐term reliable pacing threshold, minimal tissue reaction, 11 and limited occurrence of electrochemical, inflammatory reaction products 12 . Furthermore, for reliable detection of cardiac signals, a low impedance of the phase interface, 13 and low generation of artifacts (electrochemical noise) 14 is mandatory.…”

Mechanism of Decrease in the Atrial Potential After Implantation of a Single‐Lead VDD Pacemaker:

“…The pacing and sensing performance deteriorate after intravenous implantation of a pacemaker. The mechanism of this deterioration is known to be an increase of the distance between the electrode and the normal cardiac muscle caused by inflammatory reactions on the surface in contact with the electrode and the tissue surrounding the electrode 12–15 . Similar changes were observed on the surface of the atrium in contact with the lead, 9–11 and may relate to the deterioration of the atrial sensing performance in the VDDPS.…”