Left Ventricular Septum Pacing in Patients by Transvenous Approach Through the Inter-ventricular Septum

Cardiac pacing is the only effective treatment for symptomatic bradycardia. The right ventricular apex (RVA) has become the most frequently used ventricular pacing site. However, RVA pacing has been shown to cause left ventricular (LV) dyssynchrony wich can lead to LV dysfunction and development of heart failure. Recent studies in animals have demonstrated that pacing at the LV septum induces significantly less ventricular dyssynchrony than RVA pacing and is able to improve LV function to a similar degree as biventricular (BiV) pacing. In addition it was shown that a LV septum lead can be placed permanently by driving a lead with extended helix from the RV side through the inter-ventricular septum into the LV endocardial layer. This was shown to be a feasible and safe procedure and lead stability was shown during four months of follow-up in otherwise healthy and active canines. LV septum pacing may therefore be a good treatment alternative in patients with symptomatic bradycardia, as well as patients with an indication for cardiac resynchronization therapy (CRT). The purpose of this study is to translate the findings from preclinical studies to the clinical situation by investigating the feasibility, long-term lead stability and safety of LV septum pacing by transvenous approach through the inter-ventricular septum in patients.