Swimming and Oversensing
Any swimmers out there? Using Boston? I’m a 3-year recipient of a dual sensor Boston Accolade, and it’s been working fine. EXCEPT for some recent issues with the MV (Minute Ventilation) sensor.
In the last month, the MV sensor was twice disabled by the SAM monitor. This is a safety function to guard against oversensing. When I studied the dates and times, I realized that in both cases, I was swimming (in an outdoor, club, 50m pool). The snapshots clearly show noise on both leads.
After the first one, I went back to the Device Clinic and had them check for any physiologic issues (doing arm movements and such while watching the online programmer during interrogation), and everything was clean and fine. No lead problems. Everything within range. And then they turned the MV sensor back on. Only to have it go out again a couple weeks later.
They (the docs, the nurses, the Boston reps) think it’s an external EMI event causing this. But I’ve studied the pool in question, talked to the head of maintenance there, and even done my own metering of AC/DC current (which is the suspected cause). Nothing shows up. (FYI: there are no underwater lights in that pool) And adding to the mystery is that the problem is INTERMITTENT, i.e., the sensor did NOT shut down on a couple of pool visits between the visit to the device clinic and the second shutdown of the MV sensor.
So the MV sensor is currently off, and my EP is okay keeping it that way for a while. I have partial inherent conduction at higher BPMs, so currently don’t really need pacing while swimming (or doing anything else that raises my heart rate), and the other sensor (Accelerometer) is working fine.
But in the meantime I’m struggling to understand the mystery behind what’s causing this oversensing and the MV sensor shutdowns.
Anyone else have similar experiences? Thanks for your inputs.