Ventricular Synchrony in Targeted Right Ventricular Septal Pacing: A Prospective Paired Comparison to Apical Placement.

BACKGROUND/

OBJECTIVES

Right ventricular (RV) apical pacing, the standard pacing approach, often induces ventricular dyssynchrony, potentially impairing cardiac function. This study aims to investigate whether targeted RV septal pacing, guided by functional electrophysiological feedback during implantation, reduces ventricular dyssynchrony compared to conventional apical pacing.

METHODS

This prospective, observational study included 18 patients with standard pacing indications (second-degree or intermittent third-degree atrioventricular block, sinus node disease) undergoing dual chamber pacemaker implantation. Each patient initially underwent temporary transvenous RV apical pacing via femoral access, followed by permanent ventricular lead implantation using a functionally guided technique targeting the RV septum. Electrocardiographic (QRS duration) and echocardiographic parameters (septal-posterior wall delay-SPWD, interventricular mechanical delay-IVMD) were measured at baseline, during RV apical pacing, and during targeted septal pacing. Comparisons were performed using paired within-subject statistical analysis. Lead parameters and follow-up data were also collected after implantation.

RESULTS

RV pacing significantly increased ventricular dyssynchrony parameters compared to baseline, regardless of lead position. Targeted RV septal pacing, however, resulted in significantly lower dyssynchrony than conventional RV apical pacing as quantified by QRS duration, SPWD and IVMD. No acute procedural complications were observed, and pacing lead parameters remained stable during follow-up.

CONCLUSIONS

Targeted RV septal pacing, guided by electrophysiological criteria during implantation, was associated with significantly lower ventricular dyssynchrony than conventional apical pacing. These exploratory findings from an acute paired comparison suggest that functionally guided RV septal pacing may represent a practical alternative to conventional apical pacing and warrant confirmation in larger studies with long-term clinical follow-up.