Lower intercostal space V1 placement to guide conduction system pacing lead implants.

The initial criterion to achieve conduction system area pacing (CSP) is the presence of a terminal R wave in lead V1. Different configurations were used to determine that placing V1 in lower right intercostal spaces results in a greater amplitude of the terminal R waves when the CSP lead is placed deep in the mid-septal or antero-septal locations. Easily identified terminal R wave in V1 will be more practical and potentially reduce the number of sites attempted for left bundle branch area pacing (LBBaP), resulting in faster procedures and reducing potential complications such as septal perforation.