Optimal electrode position for transvenous defibrillation: a prospective randomized study

Arrhythmia Services, Oregon Health Sciences University, Portland 97201, USA.

OBJECTIVES. This study was performed to determine the optimal position for the proximal electrode in a two-electrode transvenous defibrillation system. BACKGROUND. Minimizing the energy required to defibrillate the heart has several potential advantages. Despite the increased use of two-electrode transvenous defibrillation systems, the optimal position for the proximal electrode has not been systematically evaluated. METHODS. Defibrillation thresholds were determined twice in random sequence in 16 patients undergoing implantation of a two-lead transvenous defibrillation system; once with the proximal electrode at the right atrial-superior vena cava junction (superior vena cava position) and once with the proximal electrode in the left subclavian-innominate vein (innominate vein position). RESULTS. The mean (+/- SD) defibrillation threshold with the proximal electrode in the innominate vein position was significantly lower than with the electrode in the superior vena cava position (13.4 +/- 5.7 J vs. 16.3 +/- 6.6 J, p = 0.04). Defibrillation threshold with the proximal electrode in the innominate vein position was lower or equal to that achieved in the superior vena cava position in 75% of patients. In patients with normal heart size (cardiothoracic ratio < or = 0.55), the improvement in defibrillation threshold with the proximal electrode in the innominate vein position was more significant than in patients with an enlarged heart (innominate vein 13.0 +/- 6.5 J vs. superior vena cava 17.9 +/- 5.1 J, p < 0.01). In patients with an enlarged heart, no difference between the two sites was observed (innominate vein 13.9 +/- 4.5 J vs. superior vena cava 13.6 +/- 8.3 J, p = NS). CONCLUSIONS. During implantation of a two-lead transvenous defibrillation system, positioning the proximal defibrillation electrode in the subclavian-innominate vein will lower defibrillation energy requirements in the majority of patients.

This article has been cited by other articles:

				K. A. Michael, G. R. Veldtman, J. R. Paisey, A. M. Yue, S. Robinson, S. Allen, N. S. Sunni, C. Kiesewetter, T. Salmon, P. R. Roberts, et al. Cardiac defibrillation therapy for at risk patients with systemic right ventricular dysfunction secondary to atrial redirection surgery for dextro-transposition of the great arteries Europace, May 1, 2007; 9(5): 281 - 284. [Abstract] [Full Text] [PDF]

				R. Gradaus, D. Bocker, A. Dorszewski, B. Lamp, D. Hammel, G. Breithardt, and M. Block Fractally coated defibrillation electrodes: Is an improvement in defibrillation threshold possible? Europace, January 1, 2000; 2(2): 154 - 159. [Abstract] [PDF]

				J. Winter, J. E. Heil, C. Schumann, Y. Lin, C. M. Schannwell, U. Michel, J. D. Schipke, H. D. Schulte, and E. Gams Effect of implantable cardioverter/defibrillator lead placement in the right ventricle on defibrillation energy requirements. A combined experimental and clinical study Eur. J. Cardiothorac. Surg., October 1, 1999; 14(4): 419 - 425. [Abstract] [Full Text] [PDF]

				Y. Yamanouchi, K. A. Mowrey, M. J. Niebauer, P. J. Tchou, and B. L. Wilkoff Additional Lead Improves Defibrillation Efficacy With an Abdominal `Hot Can' Electrode System Circulation, December 16, 1997; 96(12): 4400 - 4407. [Abstract] [Full Text]

				M. J. Niebauer, B. Wilkoff, Y. Yamanouchi, T. Mazgalev, K. Mowrey, and P. Tchou Iridium Oxide–Coated Defibrillation Electrode : Reduced Shock Polarization and Improved Defibrillation Efficacy Circulation, November 18, 1997; 96(10): 3732 - 3736. [Abstract] [Full Text]

				D. Newman, A. Barr, M. Greene, D. Martin, M. Ham, S. Thorne, and P. Dorian A Population-Based Method for the Estimation of Defibrillation Energy Requirements in Humans : Assessment of Time-Dependent Effects With a Transvenous Defibrillation System Circulation, July 1, 1997; 96(1): 267 - 273. [Abstract] [Full Text]