I went this route when cardiologist pushed for last year.  This was after a couple of Cardioversions for afib/flutter.  Over the last six years of an afib journey I have had 3 PVAs (last one with new mapping technology) and 12 CVs.  

My GP ordered up a relatively inexpensive DIY test kit to start.  It showed around 15 events per hour.  Not a lot but over the threshold they are looking for.  So we did the rent-to-own thing that seems popular with the insurance companies and got a state of the art resmed machine.  Used the nose-only with the nozzles at first.  Then switched to the nose pillow.

Got through the "rent-to-own" with insurance paying period but have suspended use as of now.  Focused on finishing weight loss that has been 15 year project to get to the old "target weight".  Mrs. says no snoozing and the machine was recording only 1 or 2 events per hour for the 3 to 5 hours I would wear it. 

I am a side/half stomach sleeper with special (hard/firm) side sleeper pillow.  That maybe one reason I quit.  Headgear would hurt when waking in middle of night.  5 hours was my max usually. 3 or 4 was more typical. Also would go to mouth breathing.  The reason for this - allergies that I have ignored for years.  So now I am a flonas fan before going to bed. 

Back in 2017 my first sleep apnea test showed sever apnea.  But that after a couple months on the front line afib drugs that cause weight gain.  I gained 15 to 20 pounds after a month on those medications.  So I was 30 pounds heavier during that test.  It was also with old clunky gear to do the measuring and had to sleep on my back.  I was a miserable night - but was doing what was told by docs. 

There is tie-in with sleep apnea and cardio issues.  Your whole cardio-pulmonary system is designed to keep your blood chemistry in balance and restricting or changing one forces change in the other to try to compensate.  If your O2 get low your body will kick in to get either more air and failing to do that it will try for a  faster heart rate to move the blood faster.  So the stress on the heart is real with apnea. 

 

 

 

 

@Bluegrasscardthat is very similar to my CPap journey too. Tried it years ago, couldn't get comfortable and easily gave up on it. Fast Forward to years later and my sleep apnea was so bad it put me into heart failure. I couldn't sleep more than a few minutes at a time at night. I was so hard headed about it, that it nearly killed me...seriously. 

The fact that the machine was only registering 1 or 2 events per hours for you shows that it was working. I also sleep on my side and stomach, I wear a mask over my mouth and nose so if I switch to mouth breathing due to nasal congestion, no problems. Ensure that your mask isn't too tight, it shouldn't be uncomfortable. 

The first six months that I had it I never once woke up in the middle of the night, not even to go to the restroom. It has been a godsend to me.

I am a side/belly sleeper and use My Pillow pillow for side sleepers. You can squish your holes for the masks, your arms, whatever. Don’t laugh. It works. 
I have both obstructive and central nervous system apnea and use a heated humidified Resmed now with nasal pillow. Started with full face years ago. I also have lousy sinuses so use an over the counter nasal spray when needed. 

The power went out a few nights ago, the sudden drop in positive air pressure woke me up gasping. I thought I was dying. Then I tried to turn a light on and nothing, pitch black...at this point I thought that I was dead. Took just a minute to figure out that I wasn't dying and the power was just out. ?