Costa R

Effectiveness of epicardial atrial pacing using a bipolar steroid-eluting endocardial lead with active fixation in an experimental model

PURPOSE To assess the effectiveness of bipolar epicardial atrial pacing using an active fixation bipolar endocardial lead implanted on the atrial surface in an experimental model. METHODS A total of ten Large White adult pigs underwent pacemaker implantation under general anesthesia. Atrial pacing and sensing parameters were obtained at the procedure, immediate postoperative period and on the 7th and the 30th postoperative in unipolar and bipolar configurations. RESULTS All procedures were successfully performed. There were no perioperative complications and no early deaths. Atrial pacing and sensing parameters for both unipolar and bipolar modes remained stable throughout the study. We observed a progressive increase in atrial thresholds, ranging from 0.49 ± 0.35 (at implantation) to 1.86 ± 1.31 volts (30th postoperative day), in unipolar mode. Atrial impedance measurements decreased slightly over time, ranging from 486.80 ± 126.35 Ohms (at implantation) to 385.0 ± 80.52 Ohms (30th postoperative day). Atrial sensing measures remained stable from the immediate postoperative period until the end of the study. CONCLUSION The bipolar active fixation endocardial lead implanted epicardially can provide stable conditions of pacing and sensing parameters throughout the postoperative follow-up.

Pacemaker implantation through pericardial reflections under fluoroscopic guidance: a novel approach for patients with limited venous access

Methods Between June 2006 and November 2011, 15 adult patients underwent epimyocardial atrioventricular pacemaker implantation through a minimally invasive subxiphoid approach and pericardial window. Mean age was 46.4 ± 15.3 years and 9 (60.0%) patients were male. Patients selected for this new surgical approach were not amenable to transvenous lead placement due to: multiple abandoned leads (5), venous occlusion (3), presence of retained lead fragment in the intravascular after previous device extraction (3), tricuspid valve vegetation under treatment (2) and uncorrected intracardiac defects (2).