2.4 Measuring the distance between the pacing electrode and the
coronary artery
As shown in Figure 2, using a Beijing Sichuang technology system, we
measured the vertical distance from the tip of the pacing electrode to
the anterior descending artery during systole, with the positive head
position (AP + CRA 30°), foot position (AP + CAU 30°), left shoulder
position (LAO 30° + CRA 20°) and spider position (LAO 45° + CAU 30 °).
The maximum value was recorded, which was closest to the actual spatial
distance between the tip of the pacing electrode and the anterior
descending artery. The measurement results are represent using two
decimal places. The same method was used to measure the distance from
the tip of the pacing electrode to the posterior descending branch of
the right coronary artery and to the posterior branch of the left
ventricle.