Congestive Heart Failure - Heart rate drop while walking normal?

I would say no, but I'm not an expert in cardiac function under load. The normal response, I would think, when one's physical demand is higher than when at rest, is for the heart to compensate for the added energy output of the muscles to increase rate and pressure. In response, the lungs also normally increase their rate of exchange by flushing out CO2 more quickly, and this is accomplished also by an increased rate in breathing.

It would be interesting to see if you were standing still for few minutes checked your pulse and then rechecked with continuous O2 what your pulse would show before exertion.Maybe it goes down from oxygen level change. A good questio for your cardiologist. My smartwatch lets me check both.

@seniormed, may I ask which smartwatch you're using that shows both pulse and oxygen level?

I know the Apple Watch can, but this function is blocked in the US because of a third party patent.

The Samsung Galaxy series can from 4 on up to the soon-to-be-released 8. In Canada, at least, my 4 and 6 can show me blood pressure, heart rate, oxygen sat, ECG (including AF detection), time spent sleeping and how long in each stage, etc. The Series 8 is rumored to be able to detect blood glucose levels. In the case of the blood pressure monitor, it must be re-calibrated with a proper cuff every 28 days, and you get a reminder a couple of days ahead of that deadline...after which you cannot use that function unless you have recalibrated it meanwhile.