Does anyone know if having *** implants impedes the functioning of the Garmin chest strap heart rate monitor? My wife had a mastectomy and prosthesis fitted. I have a Garmin heart monitor which works on me fine but we cannot get it to work on her - the sensor is recognised by the head unit, the rate shown is a constant 75 and doesn't change with effort - concurrent use of another HR monitor (Apple Watch) shows her HR rising as you would expect. Thanks