The double guidewire approach for transcoronary pacing in a porcine model.

BACKGROUND: Transcoronary pacing is used for treatment of unheralded bradycardias in the setting of percutaneous coronary interventions (PCI).

OBJECTIVES: In the present study we introduced a new concept - the double guidewire approach - for transcoronary pacing in a porcine model.

METHODS: Transcoronary pacing was applied in 16 adult pigs under general anaesthesia in an animal catheterization laboratory. A special guidewire with electrical insulation by PTFE coating except for the distal part of the guidewire was positioned in the periphery of a coronary artery serving as the cathode. As the indifferent anode, an additional standard floppy tip guidewire was advanced into the proximal part of the same coronary vessel. The efficacy of double guidewire transcoronary pacing was assessed by measurement of threshold and impedance data and the magnitude of the epicardial electrogram compared with unipolar transcoronary pacing using a standard cutaneous patch electrode as indifferent anode.

RESULTS: Transcoronary pacing was effective in all cases. Pacing thresholds obtained with the double guidewire technique (1.5 ± 0.9 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.2 ± 0.7 V) and unipolar transvenous pacing against the same cutaneous patch electrode (1.5 ± 1.0 V). Bipolar transvenous pacing yielded the lowest pacing threshold at 0.8 ± 0.4 V.

CONCLUSIONS: Transcoronary pacing in the animal model with the novel "double guidewire approach" is a simple and effective pacing technique with comparable pacing thresholds obtained by standard unipolar transcoronary and transvenous pacing.