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.