Electrocardiography Recordings in Higher Intercostal Space for Children With Right Ventricular Outlet Obstruction Reconstruction Operation

Background and Objectives: We checked traditional and high-level precordial electrocardiogram (ECG) leads in patients who had undergone right ventricular outlet obstruction (RVOT) reconstruction surgery and evaluated the effect of ECG lead position on their QRS duration. Subjects and Methods: We enrolled 34 patients who had undergone surgery for congenital heart disease with RVOT obstruction and who had received followed up care that included recorded ECG at a pediatric cardiac out-patient clinic. The control group included 29 patients who did not have hemodynamically significant intracardiac abnormality. We recorded traditional standard 12-leads ECG from the 4th intercostals space, and moved the precordial leads to the 3rd and 2nd intercostals spaces, and recorded ECGs repeatedly. Results: In all groups, there was no significant difference of mean QRS duration and QTc interval between traditional standard 12-leads ECGs and ECGs at higher intercostals spaces. There was no significant difference of ECG parameters between groups. In the control group, the degree of the change between the 4th intercostals space (ICS) QRS and 3rd ICS QRS was significant (p=0.031), and although, it was insignificant, ECGs at the 3rd ICS showed decreased QRS duration in group 1 (V1: 3rd ICS 119.21${\pm}$21.53 msec vs. 4th ICS 122.80${\pm}$31.78 msec. V2: 3rd ICS 113.68${\pm}$19.43 msec vs. 4th ICS 118.24${\pm}$19.16 msec). Conclusion: Although the positional change of ECG leads did not result in a significant effect on measuring QRS duration after surgery, ECG leads at the 3rd ICS rather than at the 4th ICS may cause alteration of ECG readings. Therefore, we suggest that ECGs should be recorded in as accurate a position as possible.