Implantable atrial defibrillator with a single-pass dual-electrode lead

J Am Coll Cardiol. 1999 Jun;33(7):1974-80. doi: 10.1016/s0735-1097(99)00138-2.


Objectives: We examined the feasibility and efficacy of using a single-pass, dual-electrode (Solo) lead for atrial fibrillation (AF) detection and defibrillation.

Background: The efficacy and safety of an implantable atrial defibrillator (IAD) has been extensively studied; however, separate right atrial (RA) and coronary sinus (CS) defibrillation leads are used for the present system.

Methods: We studied the use of the Solo lead for AF detection and defibrillation in 17 patients who underwent cardioversion of chronic AF. The Solo lead with a proximal 6-cm RA electrode and a distal 6-cm spiral-shaped CS electrode were positioned into the CS with the RA electrode against the anterolateral RA wall. The RA-CS electrogram signal amplitudes were measured and the efficacy of the Solo lead for AF detection and defibrillation was assessed by using an external version of the IAD.

Results: The leads were inserted in all patients without complication (mean fluoroscopy time: 13.3+/-6.8 min). The mean RA-CS signal amplitude was 484+/-229 microV during sinus rhythm and 274+/-88 microV during AF (p < 0.05). All patients had satisfactory atrial signal amplitude to allow accurate detection of sinus rhythm. Successful cardioversion was achieved in 16/17 (94%) patients with an atrial defibrillation threshold of 320+/-70 V (5.5+/-2.7 J). Insufficient interelectrode spacing resulted in suboptimal electrode locations, associated with a lower atrial signal amplitude, a higher atrial defibrillation threshold and diaphragmatic stimulation.

Conclusions: These results suggest a simplified lead configuration with optimal interelectrode spacing can be used with an IAD for AF detection and defibrillation.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Atrial Fibrillation / physiopathology
  • Atrial Fibrillation / therapy*
  • Defibrillators, Implantable*
  • Electric Countershock / instrumentation*
  • Electrocardiography, Ambulatory
  • Electrodes
  • Feasibility Studies
  • Female
  • Follow-Up Studies
  • Heart Rate
  • Humans
  • Male
  • Middle Aged
  • Posture / physiology
  • Prosthesis Design
  • Treatment Outcome