Relationship between electrode geometry and effectiveness of ventricular defibrillation in the dog with catheter having one electrode in right ventricle and other electrode in superior vena cava, or external jugular vein, or both

Abstract
A catheter having three metal sleeves, each 6 mm long and separated by 2 mm, in a distal position, and four sleeves, each 20 mm long and separated by 25 mm, in a more proximal position was inserted through a jugular vein and its tip positioned in the apex of the right ventricle in each animal. The effectiveness of 60 combinations of sleeves in reversing ventricular fibrillation was studied in 1,440 episodes. For a given energy, the effectiveness is higher when the most distal sleeve is used in conjunction with the middle or both other sleeves for the electrode within the ventricle and two or more sleeves are used for the other electrode.