Endocardial vs. Subendocardial Electrode Placement
The most important consideration in determining how to implant a lumenless lead is to determine the target of the electrode. With standard lead implantation in the atrium, on the ventricular myocardium or even on the His bundle, the desired outcome is implantation of the electrode at the level of the endocardium. In the case of ”deep septal pacing” the goal is to penetrate the lead well into the myocardium, capturing the left bundle. The technique of fixation is dramatically different between the two. For endocardial placement, it is important to limit the number of turns of the hub of the lead to no more than 4 or 5 turns. For deep septal pacing multiple turns are used in order to embed the lead into the myocardium. The use of this technique at the right ventricular apex or in the atrium could significantly increase the risk of perforation.