AvCan had a blog post on transceiver interference: https://avalanche.ca/blogs/mitigating-avalanche-transceiver-interference
Advice from a guide on an avalanche training course I took last year is simply not to wear a HRM while ski touring.
If you want an idea of your HR while touring, my suggestion would be to wear a HRM while doing a tour in terrain with minimal avalanche risk (simple terrain, low angle, no overhead hazard, etc.) and then use the readings as a proxy for other tours.