"...Breathing in cold air is another cause of heart attack in our age group especially with a compromised heart..."

You won't believe this, but several people posting on afibbers.org forum have claimed to stop a full-blown AF episode they putting their heads out a window on a cold winter's day or night. I think I recall that a cold shower can do the same. Over on MedCram, a YouTube channel, Dr. Schuelt said that at the start of COVID, he, an ER physician, pulmonologist, and lecturer at a CA university, he began to take a cold 5 minute shower when he got home, first to ensure he was mostly rid of any virus and other pathogens, but also to stress his system to improve its immune response. This is well-established in the literature, so don't think he's just a flake.

My last "episode" was about a month ago. My HR went up to 220 (as it's done when hospitalized). I knew when it was coming on and immediately asked my daughter for help. I practiced breathing, laid on my back with my legs up, splashed my face with cold water, did the bearing down technique, and took my Flecanide. None of which helped immediately. My daughter read something on-line about the cold water and the diving reflex (or whatever it's called) and filled a bowl with lots of ice and cold water. You're supposed to take 3 deep breaths and then on the 3rd one, hold your breath, and dunk your head in the cold water. Hold under water for as long as you can and then come up for air. My HR dropped from 200 (at this point) to 90 in a matter of about 45 seconds. It was pretty amazing and a huge relief.