Figure 1.
Illustration of the lead location in each group.
A: anterior basal wall, I: inferior basal wall, S: septum, R: right ventricular anterior basal wall, L: left ventricular anterior basal wall, AP: apex.
Figure 2.
Example of intracardiac electrogram recorded by pacing system analyzer (200
mm/s). A. Onset of COI, manifested as ST-segment elevation after R wave deflection and increase of intracardiac electrogram duration (IED). B. Resolution of COI, ST-segment declined to less than 1/4 of R wave amplitude, and the significant decrease in IED also occurred.
Figure 3.
Comparison of Intracardiac EGM variables derived from isolated rabbit hearts.
Panel A. Intrinsic R wave amplitude showed no significant dissimilarity regarding to different lead positionings. Panel B. Contacted leads presented the smallest magnitude of ST-segment elevation with the most rapid decline, followed by half rotated leads, while fully rotated leads showed the biggest COI amplitude and the slowest recovery. Note that there was no difference between half and fully rotated leads at 0 min. Panel C and D depicted the same findings as Panel B in the value of ST/R and IED, respectively. *: p<0.05 (compared with half and fully rotated leads); †: p<0.05 and ‡: p<0.01 (compared with fully rotated leads).
Table 1.
Time course of COI from onset to resolution.
Figure 4.
Comparison of Intracardiac EGM variables derived from in vivo hearts.
Panel A, B and C showed the similar findings observed in Figure 3. Panel D. No difference in IED between half and fully rotated leads at any time point. *: p<0.05 and †: p<0.01 (compared with half and fully rotated leads); ‡: p<0.05 and: §: p<0.01 (compared with fully rotated leads).
Figure 5.
Correlation between COI time course and acute Lead Stability.
COI time course from onset to resolution was significantly correlated with the force in order to detach the lead from myocardium (r = 0.72, n = 48, p<0.001).