How to improve AHI/next steps

[Donag]

I had a syncopal episode (drop attack) in July and a full work up that revealed obstructive sleep apnea. I am tired towards the end of the day, but my work days are super busy - I have a very low Epworth scale score.

I have been using APAP since 8/27/2019. My diagnostic AHI was 37. My sleep lab test showed that I need a full face mask as when I use a nasal mask I mouth breath during REM muscle relaxation - and this leakage bumps me out of REM. Initially, I set the pressure as recommended per split sleep study 5 - 10. I adjusted this upward to 13 - 20.

Oskarreport1.jpg (472.3 KiB) Viewed 306 times

I have tried a variety of masks and the one that provides the best AHI results is the Dreamwear full face mask. I have had one night with this at an AHI of 1.0. I have been unable to repeat this. Other masks uniformly result in a higher AHI. Recently, my AHI has been stuck at around 5 with the same Dreamwear full Face Mask (medium/medium). It is uncomfortable - slight soreness on nostril area and deep dents that take an hour or two to fade in the morning. Loosening the straps results in loud leaks. However, if I get good scores, I am happy to continue with this mask.
I have some nasal stuffiness and when I initially used oxymetazoline nasal spray (Afrin). I had a 1 month Biotelo cardiac event monitor on at the time and I had some subtle palpitations I recorded, and had a call 10 mins from a cardiologist stating I had 14 beats of non-sustained ventricular tachycardia. I attribute this to the alpha-1 adrenoceptor agonist properties of the oxymetazoline.
I want to have a low AHI to minimize my risk of cardiac rhythm disturbance. I haven't noticed a surge of wakefulness with any AHI so I am targeting the lowest AHI I can possibly get (assuming that this number is not higher due to artifact).
Questions:
- Does the attached record suggest any further adjustments?
- Why do different masks result in varying AHIs? - Does each require a pressure titration?
- Am I better off putting up with a mask that causes some discomfort, but gives me a better AHI, or should I find the most comfortable mask and try to optimize that mask?
- Is a nasal mask with a chin strap a good alternative to a face mask?

[LSAT]

Most of your events are CAs. Those are Clear Airway events. You stopped breathing but there was no airway blocksge. Often from restlessness, rolling over
or breathing while awake. Mask changes will have little effect on CAs..Use the mask that fits the best.

[Jas_williams]

I would look at reducing your flex setting to 1 to see if it helps reducing the ca’s