title: [Implantable cardioverter/defibrillators with endocardial electrode systems: long-term stability of the defibrillator's effectiveness].
abstract: The vast majority of cardioverter/defibrillator implantations is performed with non-thoracotomy lead systems. The temporal stability of defibrillation energy requirements is well established for epicardial defibrillation lead systems, but not for non-thoracotomy lead systems. The defibrillation energy requirements were reevaluated in 30 patients, 13 months after implantation of a cardioverter/defibrillator with a non-thoracotomy lead system. The study patients group consisted of 4 females and 26 males; mean age 60.1 +/- 10.5 years; mean left ventricular ejection fraction was 32.2 +/- 6.2%. Coronary artery disease was the underlying heart disease in 12 patients, dilated cardiomyopathy in 15 patients, and artificial valve replacement in 3 patients. There was no clinical progression in the underlying heart disease between defibrillator implantation and control measurements; left ventricular ejection fraction was unchanged (32.2 +/- 6.2 vs. 32.3 +/- 6.4%); no changes occurred regarding patients' clinical status. In 27/30 patients the defibrillation threshold at defibrillator implantation could be reconfirmed at control measurements. The mean defibrillation energy/requirements at implantation (14.4 +/- 4.8 Joules) were unchanged compared to control measurements (14.8 +/- 4.6 Joules). A temporal stability of defibrillation energy requirements could be established for the monophasic (n = 15; 18.0 +/- 4 vs. 18.1 +/- 3.4 Joules) as well as for the biphasic waveform (n = 15; 11.1 +/- 3.4 vs. 11.5 +/- 2.9 Joules). The results of intraoperative defibrillation thresholds measurements are predictive for chronic defibrillation energy requirements in patients with non-thoracotomy lead systems.
authors.affiliation: Institut der Max-Planck-Gesellschaft, Bad Nauheim.
authors.forename: J
authors.initials: J
authors.lastname: Neuzner
authors.forename: H F
authors.initials: HF
authors.lastname: Pitschner
authors.forename: R
authors.initials: R
authors.lastname: Stöhring
authors.forename: P
authors.initials: P
authors.lastname: Reinisch
authors.forename: M
authors.initials: M
authors.lastname: Schlepper
mesh_terms: D000368:Aged; D001674:Bioelectric Energy Sources; D017147:Defibrillators, Implantable; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors
vernacular_title: Implantierbare Kardioverter/Defibrillatoren mit endokardialen Elektrodensystemen: Langfristige Stabilität der Defibrillationseffektivität.