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Optimal electrode position for transvenous defibrillation: a prospective randomized study.

K C Stajduhar·G Y Ott·J Kron·J H McAnulty·R P Oliver·B T Reynolds·S W Adler·B D Halperin
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Abstract

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.

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AgedBrachiocephalic VeinsDefibrillators, ImplantableElectric CountershockElectrodes, ImplantedFemaleHumansMaleMiddle AgedProspective StudiesTachycardia, VentricularVena Cava, SuperiorVentricular FibrillationClinical TrialComparative StudyJournal ArticleRandomized Controlled Trial

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K C Stajduhar, G Y Ott, J Kron, J H McAnulty, R P Oliver, B T Reynolds, S W Adler, B D Halperin. 1996. Optimal electrode position for transvenous defibrillation: a prospective randomized study.. https://doi.org/10.1016/0735-1097(95)00380-0

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