Differences in left ventricular dyssynchrony between high septal pacing and apical pacing in patients with normal left ventricular systolic function.

Background And Purpose: Permanent right ventricular apical pacing can result in heart failure due to ventricular mechanical dyssynchrony. The purpose of the study was to define differences in left ventricular dyssynchrony between high septal pacing and apical pacing using tissue Doppler imaging (TDI) and two-dimensional (2D) speckle-tracking echocardiography (STE).

Methods: The subjects were 60 patients with normal left ventricular systolic function who underwent implantation of a permanent pacemaker.

Evaluation of bi-atrial pacing and single site right atrial pacing for the prevention of atrial fibrillation.

Atrial resynchronization resulting from simultaneous pacing of the atria may adjust inter- or intra-atrial asynchrony and prevent atrial fibrillation (AF). The purpose of this study was to assess the efficacy of bi-atrial pacing (BAP) in preventing AF, and the safety of this system. The effect of BAP was compared with single site right atrial pacing (RAP) in 6 patients with sick sinus syndrome and paroxysmal AF in a prospective switchover trial.