Abstract
167
Objectives Optimal site for cardiac pacemaker implantation remains unclear. We aim to evaluate the effect of conventional Right ventricular apical (RVA) pacing versus Right ventricular outflow tract (RVOT) pacing on left ventricular (LV) function and synchrony using equilibrium radionuclide angiography (ERNA).
Methods We prospectively evaluated twenty patients who underwent dual-chamber, rate-modulated (DDDR) pacemaker implantation. All patients had LV ejection fraction (EF) > 50% and no history of cardiac disease. Out of 20 patients, 10 had pacemaker lead positioned at RVA site and 10 at the RVOT site. All patients underwent ERNA within 1 week post pacemaker implantation and at 6 month follow-up. All studies were done under forced pacing at heart rate of 100/min. ERNA was performed as per standard protocol. Standard deviation of LV mean phase angle (SD LV mPA) which was derived by Fourier first harmonic analysis of phase images to quantify left intra-ventricular synchrony and LVEF were evaluated at baseline and at 6 month follow up.
Results No significant difference was observed between the two groups with respect to age (p 0.937), gender (p 0.857) and LVEF (p 0.871) at baseline. In the RVA group, no significant change in LVEF was observed over 6 month follow up (from 54 ± 4.2% to 54.7 ± 6.9%; p 0.712); in the RVOT group too, LVEF did not change significantly (from 53 ± 2.7% to 53.5 ± 7.8%; p 0.774). Similarly, no significant change in SD LV mPA was observed over 6 month follow up in the RVA group (from 12.5° ± 3° to 14.2° ± 2.7°; p 0.240) as well as in the RVOT group (from 12.4° ± 3.5° to 14.6° ± 3.7°; p 0.161).
Conclusions No significant difference was observed between patients with RVOT and RVA pacing in terms of LVEF & LV synchrony at 6 month follow-up. A longer follow-up and larger number of patients will be needed for further validation
In this issue
Jump to section
Related Articles
Cited By...
- No citing articles found.