Premium
A Second Defibrillator Chest Patch Electrode Will Increase Implantation Rates for Nonthoracotomy Defibrillators
Author(s) -
SOLOMON ALLEN J.,
SWARTZ JOHN F.,
KODAK DAVID J.,
MOORE HANS J.,
HANNAN ROBERT L.,
TRACY CYNTHIA M.,
FLETCHER ROSS D.
Publication year - 1996
Publication title -
pacing and clinical electrophysiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.686
H-Index - 101
eISSN - 1540-8159
pISSN - 0147-8389
DOI - 10.1111/j.1540-8159.1996.tb04208.x
Subject(s) - medicine , cardiology , medical emergency
Nonthoracotomy defibrillator systems can be implanted with a lower morbidity and mortality, compared to epicardial systems. However, implantation may be unsuccessful in up to 15% of patients, using a monophasic waveform. It was the purpose of this study to prospectively examine the efficacy of a second chest patch electrode in a nonthoracotomy defibrillator system. Fourteen patients (mean age 62 ± 11 years, ejection fraction = 0.29 ± 0.12) with elevated defibrillation thresholds, defined as ≥ 24 J, were studied. The initial lead system consisted of a right ventricular electrode (cathode), a left innominate vein, and subscapular chest patch electrode (anodes). If the initial defibrillation threshold was ≥ 24 J, a second chest patch electrode was added. This was placed subcutaneously in the anterior chest (8 cases), or submuscularly in the subscapular space (6 cases). This resulted in a decrease in the system impedance at the defibrillation threshold, from 72.3 ± 13.3 Ω to 52.2 ± 8.6 Ω. Additionally, the defibrillation threshold decreased from ≥ 24 J, with a single patch, to 16.6 ± 2.8 J with two patches. These changes were associated with successful implantation of a nonthoracotomy defibrillator system in all cases. In conclusion, the addition of a second chest patch electrode (using a subscapular approach) will result in lower defibrillation thresholds in patients with high defibrillation thresholds, and will subsequently increase implantation rates for nonthoracotomy defibrillators.