Supplemental Figure S1. Visualization of the right ventricular (RV) septum by contrast injection via a pigtail catheter or the cap of a leadless pacemaker delivery catheter in two patients. The RV septum in both RAO and LAO fluoroscopic images is clearly better for the pigtail catheter injection than by the cap injection. The cap injection of contrast only shows a local region of the RV while the pigtail catheter injection reveals the whole right ventricle (e.g., right ventriculography). Thus, the study used the pigtail catheter injection in the radiography group.
Supplemental Figure S2 . Example of 12-lead ECG during pacing by Micraâ„¢ leadless pacemaker at mid-septum (A) in a patient and during right ventricular apical pacing in another patient (B). ECG QRS duration appears shorter in septal pacing than in RV apical pacing. A horizontal bar represents 200 ms, the space between two red vertical line indicates QRS duration.