Micropace stimulators are compatible with RF Ablation energies

1 October 2006

A recently circulated Boston Scientific internal company test report (M.Pare et al, 24.July 2006) showed that a popular hardware EP stimulator exhibited potentially arrhythmogenic nett DC voltages on its pacing outputs when the pacing bipole is located near the ablation catheter during delivery of RF ablation energy. [This is presumably due to partial rectification by non-linear elements in output circuits.] This hazard was found to be mitigated by RF filters in some EP recorders, otherwise mitigation by a separate RF filter in the pacing circuit was recommended.

For the information of our customers, Micropace stimulators do not pose a hazard in the presence of RF ablation energies and may be left connected to patients during RF ablation.

Micropace has been aware of this issue since 2001 and Micropace stimulators have RF filters in their stimulus connection boxes and do not exhibit DC voltage on its outputs during RF energy delivery. Some early stimulators sold outside of the US prior to Jan 2001 do not have RF filters but rely on a general ‘DC Current Alarm’ safety cutout feature present in all Micropace stimulators, to detect and interrupt flow of any potentially hazardous DC currents in its output circuit. Micropace has performed in-vitro experiments similar to those by Boston Scientific since this paper was released and confirmed the absence of output DC voltages on the EPS320.

Owners of Micropace stimulators therefore do not need to take any specific action in response to these issues. Customers are neverthelsss reminded to read carefully and always follow the Warnings and Precautions in the Essential Prescriber Information section of their EPS320 User Instruction Manual – download here.