Spatial response of jejunal pacing defined by a novel high-resolution multi-electrode array.

BACKGROUND AND PURPOSE: Gastric pacing has shown preclinical success in modulating bioelectrical slow wave activity and has potential as a novel therapy for functional motility disorders. However, the translation of pacing techniques to the small intestine remains preliminary. This paper presents the first high-resolution framework for simultaneous pacing and response mapping of the small intestine.

METHODS: A novel surface-contact electrode array, capable of simultaneous pacing and high-resolution mapping of the pacing response was developed and applied in vivo on the proximal jejunum of pigs. Pacing parameters including the input energy and pacing electrode orientation were systematically evaluated and the efficacy of pacing was determined by analyzing spatiotemporal characteristics of entrained slow waves. Histological analysis was conducted to determine if the pacing resulted in tissue damage.

RESULTS: A total of 54 studies were conducted on 11 pigs and pacemaker propagation patterns were successfully achieved at both low (2 mA, 50 ms) and high (4 mA, 100 ms) energy levels with the pacing electrodes oriented in the antegrade, retrograde and circumferential directions. The high energy level performed significantly better (p=0.014) in achieving spatial entrainment. Comparable success (greater than 70%) was achieved when pacing in the circumferential and antegrade pacing directions, and no tissue damage was observed at the pacing sites.

CONCLUSION: This study defined the spatial response of small intestine pacing in vivo revealing effective pacing parameters for slow wave entrainment in the jejunum. Intestinal pacing now awaits translation to restore disordered slow wave activity associated with motility disorders.