Laying in bed can cause ectopic beats which can turn into AF. In the last two years, we have had two expensive mattresses both of which turned out to deteriorate quickly. When away from home, especially in Europe, I do not have this problem near as much. My wife started researching mattresses and found this website:
It has a wealth of information. We learned that latex does not support dust mites or bed bugs. Spring coils some people think can impact magnetic fields. Most mattresses are a chemical soup composed of fire retardants, formaldehyde, etc. Latex softens about 15%, memory foam about 30% and polyurethane 60% over a ten year period with most of the deterioration in the first 5 years. Pure latex mattress do not have any chemicals. And the covers are chemical free as well. We purchased a pure wool mattress cover. Wool is a fire retardant.
We purchased an all natural latex mattress from Spindle Mattress in the USA. They have a lot of good information on their website. Of course we researched many mattress makers. Spindle delivered a mattress to my home in Canada for 60% less than what a similar mattress would cost me in Canada. Now, I can sleep without as many heart issues and my wife no longer has back issues. She loves the mattress so that is a plus. The latex mattress eliminates pressure points. Not all latex mattresses are 100% latex. They are a bit pricey.
So maybe some of the heart issues related to sleeping are due to the mattresses we have on our beds. In the future, if we need a new mattress, all we need to purchase is new latex layers which will make the new mattress much less costly.