Septal versus apical pacing sites in permanent right ventricular pacing: The multicentre prospective SEPTAL-PM study

Abstract

The optimal right ventricular pacing site for patients requiring pacemaker implantation for permanent atrioventricular block is a matter of debate. Long-term right ventricular apical pacing has been associated with left ventricular ejection fraction impairment and heart failure. Right ventricular septal pacing has been proposed as an alternative. The aim of this randomized prospective multicentre trial was to compare left ventricular remodelling and outcomes between right ventricular apical and septal pacing after mid-term follow-up. Patients requiring pacemaker implantation for high-degree atrioventricular block were enrolled and randomized in a 1:1 fashion to receive a right ventricular apical or septal lead. A total of 141 patients were included, 69 in the septal group and 72 in the apical group. Both groups exhibited similar left ventricular ejection fractions after 18 months of follow-up (septal 57.1±11.9% vs. apical 57.4±13.4%), and left ventricular ejection fraction variation was similar in the two groups at the end of follow-up (septal -1.5±13.2% vs. apical 0.3±13.3%). Additionally, left ventricular volume, quality of life and 6-minute walk distance were similar in the two groups. However, patients in the septal group were more likely to be asymptomatic, with a significantly lower concentration of N-terminal prohormone of brain natriuretic peptide. Lastly, lead position did not impact 18-month survival. Pacing from the right ventricular apex does not have any detrimental effect on left ventricular systolic function compared with septal pacing over an 18-month period.