VfA delivery and implant region detection

A delivery assembly comprising:

• a mapping electrode configured to be advanced into a potential atrial pacing target implant region in the triangle of Koch region, the potential atrial pacing target implant region being a location to pace the right atrium;
• and
• a mapping analyzer operably coupled to the mapping electrode configured to determine whether an atrial slow pathway potential (ASP) is detected at the potential atrial pacing target implant region using the mapping electrode.

A delivery assembly comprising:

• a mapping electrode configured to be advanced into a potential target implant region in the triangle of Koch region;
• and
• a mapping analyzer operably coupled to the mapping electrode configured to determine whether a pacing output at a potential target implant region paces the atrium without pacing the ventricle of the patient's heart using at least one electrode of a delivery assembly.