• Welcome to Phoenix Rising!

    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of, and finding treatments for, complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia, long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

    To become a member, simply click the Register button at the top right.

Fast heart rate while sleeping, wakes me up

Gingergrrl

Senior Member
Messages
16,171
@ahimsa

This got very long but I'm not sure what to cut out. I have not idea whether it will help anyone but I do hope someone gets something out of it!

I really wanted to reply to this thread sooner but couldn't find it! Thank you for everything you typed out.

As far as I can tell the tachycardia I described in this thread was related to my problems with autonomic dysfunction and NMH. The problem seemed to be related to pushing too hard during the day. I was gradually ramping up my activities (not exercise, just errands and household duties) without realizing it. At the same time, I was gradually reducing my resting time without realizing it.

Just to clarify, do you mean that the tachycardia in your sleep was related to autonomic dysfunction and NMH? I am not sure in my case if the tachy in my sleep was related to pushing too hard during the day. All I know is that it was the very first symptom that I had that something was really wrong and it started in Jan 2013 (10 mos after I had mono and two weeks following an unknown infection.) Did yours occur exclusively during REM sleep while you were actively dreaming?

So, I got serious about reducing my activities and resting more (which is VERY HARD because I hate doing nothing). I also started mixing up a homemade electrolyte mixture (something close to Pedialyte in sodium/potassium levels) more often. I drink that instead of dinner maybe 3-4 times a week. Unlike so many folks on this forum I sleep better when I don't eat dinner (no blood sugar problems).

Did you find a correlation between resting and not having the tachycardia in your sleep? I drink all the Pedialyte, Vitalyte stuff, too. I also feel better when I do not eat dinner but then I started having hypoglycemia episodes and now I force myself to eat more whether I want to or not.

It may also be that I had (have?) some sort of co-infections that got re-activated as @CBS suggested (have not re-read the thread but I think that was mentioned?). But whatever the reason for my problem it finally did subside and has not come back.

What kind of co-infections do you mean? Also, do you mean that the tachy in your sleep is totally gone on it's own? Mine is 99% gone with a beta blocker but every once in a while, I will still have an episode (but very rarely.)

By the way, none of my doctors were helpful, sadly. And the sleep specialist that I visited had not heard of Orthostatic Intolerance. What's worse, she did not even glance at the patient handout from Johns Hopkins.

The initial cardiologist that I saw was a joke and I don't think she believed me that I was having tachy in my sleep up to 160 and 170 bpm. She said, "Well, I can get my HR that high in my spin class..." and I said, "But I am not in a spin class, I am SLEEPING!" Needless to say I switch to a new cardio who did a Zio Patch test which captured the episodes. She believed me and said they were IST and gave me the beta blocker. Neither mentioned dysautonomia or OI and I did not know the terms at the time to even ask. I am now seeing a third cardio (my current doctor) who knows about dysautonomia but does not know anything about ME/CFS.

The screening test showed no apnea and excellent blood oxygen levels, which was good to know... But I was not going to bother with a full sleep test with a doctor who did not even know about autonomic problems (and who did not want to learn!).

I did a full sleep study in 2013 which showed no sleep apnea and normal blood oxygen levels. I had very mild CFS at that time and was still working full-time and had no idea what my diagnosis was, only that I had weird tachy in my sleep. I took the beta blocker for the sleep study (which I regret) so the episode did not occur and I barely slept the entire night and it was a waste of time.

I think it's pretty well known that autonomic dysfunction can interfere with sleep.

I did not realize that at the time and am still not sure if I understand the full connection because when I am laying flat and resting or sleeping, it is the only time I can breathe normally (except for those episodes.)

I doubt that I could find a doctor *locally* to do these extra tests for co-infections. And I'm not up to any serious investment of time/money/energy/travel to go to an ME/CFS specialist. I guess I just don't believe the trade-off would be worth it. Plus, there's always the risk of running into doctors who would do more harm than good.

When you say co-infections, what do you mean? I have EBV and VZV but are you referring to viral stuff or bacterial or something else? For me, it has been worth it to travel to see an ME/CFS specialist but I know this is a personal choice and it definitely involves time, money, energy, etc, and the travel is very difficult for me in my current state (and I only do it twice per year.) It is a leap of faith that at present I feel is worth it (for me.)

Okay, now I should try to describe what I think are my two different kinds of tachycardia. One kind is due to Orthostatic Intolerance (OI) -- NMH (Neurally Mediated Hypotension) and POTS. My symptoms come on due to various NMH triggers like posture (standing still is the worst, but sitting still and upright at a desk is also bad), getting overheated, and after eating (splanchnic pooling, blood pools in the abdomen).

This is similar for me except that my BP is always low and not just when I am standing. Also, I have no problems sitting at a desk (or sitting anywhere) but I have major problems with standing, walking, eating, etc.

The tachycardia is just one of the many pre-syncope symptoms that I get.

Do you mean that you actually faint? I have never fainted in my life no matter how low my BP has gotten.

It does not come alone. I also get nausea, dizziness, brain fog, fasciculations (muscle twitches), sometimes muscle pains, and others that I can't remember right now. This, along with PEM from the ME/CFS/whatever, is disabling. I am not in bed all day but I am mostly at home. I am on disability, don't exercise, spend a lot of time resting, can't do a lot of household things, etc.

This is pretty similar to me except I don't have much dizziness or brain fog and my worst symptoms are shortness of breath and chest pressure which at it's worst is chest pain that my cardio thinks are microvascular angina spasms.

This tachycardia from OI is always part of a larger set of symptoms. What helps me is to rest in the recliner with my feet up (or lie down completely), get cooler, drink electrolytes, etc. And the drugs/supplements already mentioned (midodrine, florinef, potassium RX, salt tablets, magnesium).

I do everything you said here except for Florinef which made me sicker.

When I first saw the cardiologist for my problems with ME/CFS/NMH (sorry to those who don't like this combo of terms but I never know what to call my illness) I mentioned this other type of tachycardia as part of my medical history. Because it has never been caught on an EKG (even though I've had two holter monitors since 1990) no one knows for sure what it is.

Have you ever had a Zio Patch test? I really think you could capture it on that.

I'll end by saying that I've been sick since 1990. I think having been sick for so much longer means that I don't know whether what's going on for me is going to be even remotely relevant to you. I was much sicker early on, esp. during 1991 (difficult just to walk across the room). Many of my symptoms have changed over the years. I'm not even sure I could list all the different changes after all this time. For example, I had lots of night sweats in the beginning and now these are quite rare (once every year or two?).

Actually it was very helpful and you were very helpful in the past when we were discussing Midodrine. I really appreciate it. I relate to a lot of your experiences and the difficulty in just walking across the room. I have never had night sweats though.

Okay, that's more than enough rambling from me! :rolleyes::D

Not rambling and very helpful! Glad I am not the only one who types long posts!
 

ahimsa

ahimsa_pdx on twitter
Messages
1,921
Just to clarify, do you mean that the tachycardia in your sleep was related to autonomic dysfunction and NMH?
Yeah, that's my guess. Although it could have been something else.

But it is true that resting more and drinking more of my electrolyte mix seemed to make that symptom (waking up with fast heart rate) go away. And it has not come back.
Did yours occur exclusively during REM sleep while you were actively dreaming?
I don't remember any dreams so I'm guessing not REM sleep. But I have no way to know for sure.
Did you find a correlation between resting and not having the tachycardia in your sleep?
Yes. And, unlike your situation, I'm not on any beta blockers at all.
What kind of co-infections do you mean?
I actually know nothing about co-infections. I was just repeating a possible cause that was posted by @CBS. (By the way, @CBS, if you are reading this, thank you for the advice to be careful and slow down! That was helpful!)

I've never had detailed testing for viral infections (some limited testing many years ago--elevated titers???--but not sure how reliable it was). You probably know way more about it (you're taking anti-virals, right?) than I do!
Do you mean that you actually faint? I have never fainted in my life no matter how low my BP has gotten.
No, I've never fainted other than on the tilt table test. I used the term pre-syncope to describe the category of symptoms related to dropping blood pressure. I do get pre-syncope symptoms due to Orthostatic Intolerance and dropping blood pressure BUT these symptoms come on slowly enough that I can sit down before I ever get bad enough to faint.
This is pretty similar to me except I don't have much dizziness or brain fog and my worst symptoms are shortness of breath and chest pressure which at it's worst is chest pain that my cardio thinks are microvascular angina spasms.
I get chest pains, too. Definitely one of my earliest symptoms and I still have them. I get them mostly during PEM periods, a day or two after too much exertion or standing, and not during any actual activity. Since I've had them for 25 years I don't worry about them any more. For me, I think it's part of the OI/NMH and not part of any type of angina or spasms.
Have you ever had a Zio Patch test? I really think you could capture it on that.
If the SVT tachycardia (suspected AV Nodal Reentrant Tachycardia) ever gets bad enough then I'll ask for that test. For now it happens infrequently enough that I'm able to ignore it. As I get older it does last longer when it happens (max time is 45 minutes whereas it never used to last longer than 5 minutes) but the frequency is still pretty low.

It's like hiccups. Annoying when it happens, and tiring afterwards, but not life threatening or dangerous in any way. If it caused pain or dizziness or something like that then I'd be more worried. But it does not.

Hope this helps and that I answered all the questions. And wishing you all the best, as always!

Those first years of being ill were the hardest for me. I am not well enough to work but I am so much better than my very worst period back in 1991. So, there is always hope at least for partial improvement if not completely recovery!
 
Last edited:

Gingergrrl

Senior Member
Messages
16,171
@ahimsa

Yeah, that's my guess. Although it could have been something else.

It's still so strange to me that all these symptoms that seem purely cardiac could be autonomic issues from the brain!

But it is true that resting more and drinking more of my electrolyte mix seemed to make that symptom (waking up with fast heart rate) go away. And it has not come back.

I agree with you that resting and drinking electrolytes helps with dehydration and tachycardia but in my case, I need to take the beta blocker as well.

I don't remember any dreams so I'm guessing not REM sleep. But I have no way to know for sure.

I have extremely vivid dreams and in my case every time I have ever had the high tachycardia in my sleep (anywhere from 120 to 170 bpm) it wakes me from a dream. But it is not a nightmare and is just any random dream.

Yes. And, unlike your situation, I'm not on any beta blockers at all.

I have tried going off beta blockers but the tachycardia always returns.

I've never had detailed testing for viral infections (some limited testing many years ago--elevated titers???--but not sure how reliable it was). You probably know way more about it (you're taking anti-virals, right?) than I do!

I am taking Famvir, and hope to soon be taking Valcyte, but my overall knowledge of viral titers and how they relate to ME/CFS and dysautonomia is still quite low.

No, I've never fainted other than on the tilt table test. I used the term pre-syncope to describe the category of symptoms related to dropping blood pressure. I do get pre-syncope symptoms due to Orthostatic Intolerance and dropping blood pressure BUT these symptoms come on slowly enough that I can sit down before I ever get bad enough to faint.

It's weird but no matter how bad my symptoms get, I have never fainted in my whole life.

I get chest pains, too. Definitely one of my earliest symptoms and I still have them.

I didn't realize that you got chest pain and was wondering if you could describe what they are like? I am curious if they are similar to mine and don't want to bias your answer by saying anything further.

I get them mostly during PEM periods, a day or two after too much exertion or standing, and not during any actual activity. Since I've had them for 25 years I don't worry about them any more. For me, I think it's part of the OI/NMH and not part of any type of angina or spasms.

I was wondering how do you know whether they are any kind of angina or spasms? I am in no way saying you are wrong but am curious how this is determined, even in my own case.

If the SVT tachycardia (suspected AV Nodal Reentrant Tachycardia) ever gets bad enough then I'll ask for that test. For now it happens infrequently enough that I'm able to ignore it. As I get older it does last longer when it happens (max time is 45 minutes whereas it never used to last longer than 5 minutes) but the frequency is still pretty low.

I cannot imagine having that high tachycardia for 45 min. When it happens in my sleep, as soon as I wake up, it goes back to normal within a few minutes. Although the episode takes me several days to recover from.

Hope this helps and that I answered all the questions. And wishing you all the best, as always!

Thank you and you have always been very supportive and generous in your answers and explanations to my questions!

Those first years of being ill were the hardest for me. I am not well enough to work but I am so much better than my very worst period back in 1991. So, there is always hope at least for partial improvement if not completely recovery!

That's what I am hoping for in my own case and even a partial recovery would be great.
 

ahimsa

ahimsa_pdx on twitter
Messages
1,921
I have tried going off beta blockers but the tachycardia always returns.
Gosh, I hope it did not sound like I was suggesting that you should go off of beta blockers, or that they were not helpful. I know lots of POTS patients who need them!

I was just saying that, in my case, that one problem with fast heart rate during sleeping went away without any beta blockers. I know it's hard (if not impossible!) to remember what drugs everyone else is taking. That's the only reason I mentioned that I was not taking beta blockers.
I didn't realize that you got chest pain and was wondering if you could describe what they are like? I am curious if they are similar to mine and don't want to bias your answer by saying anything further.
The pains are sharp pains, in the upper left chest area, and they come and go. It could be anything. Doctors never know and have suggested everything from costochondritis (inflammation of the rib cage, which I think is highly unlikely) to esophagal spasms to acid reflux.

But I have read many articles and research papers over the years that have chest pains in the list of symptoms that come with OI/POTS/NMH. And I think I've also heard this in some of the online videos.

At any rate, here's one quote ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1501099/ )
Symptoms include mental clouding (“brain fog”), blurred or tunneled vision, shortness of breath, palpitation, tremulousness, chest discomfort, headache, lightheadedness and nausea. While pre-syncope is common in these patients, only a minority (~30%) actually pass out. The chest pains are almost never due to coronary artery obstruction, but are sometimes associated with electrocardiographic changes in the inferior leads, particularly when upright
And here's a quote from a different paper ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3390096/ )
Raj et al.[8] suggested the chest pains experienced in POTS are almost never thought to be due to coronary artery obstruction, but may be associated with electrocardiographic (EKG) changes in the inferior leads, particularly when upright. They suggest the left sided heart pain common among POTS sufferers is due to differences in heart chamber pressures, abnormal heart wall motions, and/or nerve damage. However, based on the Qi Fu's study[21] the chest pain may be associated with reduced blood supply to the heart, hence ischemia, which will result in the angina like chest pain.

So it makes sense to me that my chest pains are part of the whole OI/POTS/NMH complex.

I do NOT know for sure what causes my chest pains. But I have very good numbers with respect to cholesterol, no family history of heart problems, normal echocardiogram (well, 10+ years ago, I have not had one lately), normal holter monitors and EKGs, etc. I don't have any reason to think that my chest pains are from something else, especially since this whole thing (chest pains were just one of many symptoms) started when I was so young (29) and fit.

But I would never suggest that another patient should come to the same conclusion. This is just a guess about my own symptoms. I could be wrong.

This illness has so many unknowns. I have learned to live with a high level of ambiguity. :(
 

ryan31337

Senior Member
Messages
664
Location
South East, England
Hi all,

I appreciate i'm digging up an already pre-exhumed thread but I thought people may be interested in this relevant presentation: Sleep disorders in POTS.
https://www.youtube.com/watch?list=PLBPPJmonlKtBFKNgLbTHii3Ad_OnY5erV&v=PyLQlzgBsbs

The study confirms what you already know about tachycardia disrupting sleep, it also details the completely haywire sleep architecture. It's great to see theory validated with some hard results. It also made me feel better about my battles with delayed circadian rhythm (Dear Dr, its not my poor sleep hygiene!), as well as the extreme grogginess upon waking that I sometimes get that can be curiously fixed by just sleeping for another hour (abnormal late stage 3 sleep).

Enjoy,
Ryan.
 

Gingergrrl

Senior Member
Messages
16,171
The study confirms what you already know about tachycardia disrupting sleep

@ryan31337 I started to watch the video but it is about 45 min long and I was wondering if you have any idea where in the video the doctor addresses tachycardia in sleep? No worries if you do not remember and don't want you to have to go back through video but was wondering if you could summarize the tachy in sleep part? Very high tachy in sleep (approx 170 bpm) was my very first symptom in Jan 2013 that anything was wrong. Was diagnosed with IST, then POTS, then a million other diagnoses, etc. Thank you in advance!
 

ryan31337

Senior Member
Messages
664
Location
South East, England
Hi Gingergrrl,

I think the whole thing is worth a watch if you can, but maybe that's just me :nerd:

Discussion of the results start at 17min. There are quite a few interesting abnormalities and the assumption is that abnormal noradrenergic function plays a large part, which I guess fits with the main theories. Some of the stuff that goes wrong:

- Delayed circadian rhythm
- Abnormal sleep architecture, particularly in obtaining/maintaining slow wave sleep at the right time
- Abnormal HRV & heart rate spikes linked to high quantity of arousals (which seemingly doesn't happen in IST)
- Abnormal amount of leg movement in REM

I don't think this is particularly newsworthy as previous ME/CFS sleep studies have captured most of it previously, with similar assumptions made about SNS activation as cause. I thought it was interesting to see it conducted on POTS patients outside the context of ME/CFS though.
 

ahimsa

ahimsa_pdx on twitter
Messages
1,921
Last edited:

Gingergrrl

Senior Member
Messages
16,171
I thought it was interesting to see it conducted on POTS patients outside the context of ME/CFS though.

@ryan31337 Sorry I have not watched the video yet but do you mean that POTS patients could start with tachycardia in their sleep as their very first symptom of illness but that they ultimately did not have ME/CFS if they presented this way? I just want to make sure I am understanding correctly? I was first diagnosed with IST and then later the diagnosis switched to POTS. Tachy in my sleep was my very first symptom that anything was wrong. It no longer occurs b/c I take a beta blocker but I haven't found too many people whose illness started this way.
 

ryan31337

Senior Member
Messages
664
Location
South East, England
Hi Gingergrrl,

Crossed wires I think. The relevance to IST was that IST causes significant tachycardia and pulse variability in sleep but, unlike when that happens in POTS, it does not cause all the arousals that ultimately ruin our sleep. It was just for contrast I think, no indication given that it would be progressive.

With regards to the ME/CFS thing, I just meant that it was presented as if these problems were very consistent among POTS patients, whereas in the ME/CFS sleep studies it seemed a bit more variable, presumably because they were testing those with and without POTS symptoms.
 

Gingergrrl

Senior Member
Messages
16,171
Hi Gingergrrl,

Crossed wires I think. The relevance to IST was that IST causes significant tachycardia and pulse variability in sleep but, unlike when that happens in POTS, it does not cause all the arousals that ultimately ruin our sleep. It was just for contrast I think, no indication given that it would be progressive.

With regards to the ME/CFS thing, I just meant that it was presented as if these problems were very consistent among POTS patients, whereas in the ME/CFS sleep studies it seemed a bit more variable, presumably because they were testing those with and without POTS symptoms.

Hi @ryan31337 I still haven't had a chance to watch the video and apologize for all the questions! When I was first diagnosed with IST in 2013, it was because extremely high tachy was waking me up all through the night, especially during REM sleep so I had endless arousals that ruined my sleep at that time. It was happening exclusively during sleep (no postural changes) which made it seem like IST vs. POTS.

Then it completely changed to postural changes and the classic definition of POTS and I was told that it was all on a continuum (no idea if this is true?) The beta blocker controls the symptoms and I rarely have tachy in my sleep and only occasionally during the day. But when I try to taper off the BB, it all comes back very quickly. I also have very low BP and orthostatic dyspnea (but I no longer have the sleep arousals at least that I am aware of.)

I guess the second part of your post made me realize that there are ME/CFS patients without POTS or autonomic stuff and I keep forgetting that b/c dysautonomia is my #1 problem besides MCAS. It is so hard to figure out where I fit medically with all my symptoms (and I don't care about the label vs. finding the best way to treat and manage them.)
 

Mel9

Senior Member
Messages
995
Location
NSW Australia
Just found this old thread after waking up last night with high heart rate of 140 -150 bpm, probably caused by my first try at gentle water exercise yesterday (using kick board).

At 1am I was able to get my HR down to 65 bpm again by drinking water with electrolytes and Basica (to try to avoid PEM ) and extra CoQ. Hopefully I can avoid this in the future. It was a bit scary.
 
Messages
426
Location
southeast asia
@ryan31337 @ahimsa @Gingergrrl i think sleeping problem in autonomic imbalance patients was due to hormonal and ans issues? N tachycardia was part of it as well. Not because we get sleepless because of tachycardia?

Restless definitly can make tachycardia worse and resting can decrease it. I got it more often in my sleep when my health gets worse. Although sometimes i get it without knowing why.
 

Gingergrrl

Senior Member
Messages
16,171
@ryan31337 @ahimsa @Gingergrrl i think sleeping problem in autonomic imbalance patients was due to hormonal and ans issues?

@kisekishiawase It's good to hear from you and hope you are doing okay. I no longer get the tachy in my sleep (which was my very first symptom in 2013 that something was wrong) but I still get it with standing and still have POTS. I really do not know why the tachy in my sleep went away (other than the beta blocker) and it plagued me for several years where I'd wake up w/HR in the 160's and 170's. Am hoping it is gone for you as well but was not certain from your post.
 

keenly

Senior Member
Messages
826
Location
UK
I am having this problem right now! I woke up early this morning with heart racing, I was dreaming about playing rugby, and arguing with the ref. During the argument I awoke, now i have breathing problems.
 

Johnskip

Senior Member
Messages
141
I am having this problem right now! I woke up early this morning with heart racing, I was dreaming about playing rugby, and arguing with the ref. During the argument I awoke, now i have breathing problems.
wow I have dreams I'm playing basketball intensely waking up out of breath
 

keenly

Senior Member
Messages
826
Location
UK
wow I have dreams I'm playing basketball intensely waking up out of breath
Yeah it is not good. We are working our bodies during sleep. This makes me more open to trying meds like Doxepin.

On that note; Dr Cheney is looking at low dose oxygen therapy for sleep. Apparently we have a major problem with oxygen saturation during sleep, and this can be measured. This new technology allows for continuous monitoring of blood oxygen saturation all night long during sleep (www.pulseoximeter.org/cms50f.html) for $112 as well as tissue perfusion (www.pulseoximetersplus.com/quest-sleep-unit-wrist-pulse-oximeter-pc-68b/) for $275. The technology consists of a pulse oximeter on the finger tied to a wrist band that records the data while the patient is sleeping in their own environment. The recorded data on the wrist band is then transferred to a computer by a USB cord or Bluetooth and analyzed by a software package that can display the data in easy to interpret graphics.

I may start a thread about this.
 

ahimsa

ahimsa_pdx on twitter
Messages
1,921
Apparently we have a major problem with oxygen saturation during sleep, and this can be measured.
Hi @keenly -

I can't speak for other patients (many probably do have these kinds of problems) but in my case the waking up with a fast heart rate was not due to low oxygen saturation during sleep.

I had an at home sleep test (a screening test to see if a full sleep test was warranted). It found no problems with apnea (another common problem for ME patients) or with oxygen saturation.

Just FYI. More details are in previous messages on this thread.
 

ahimsa

ahimsa_pdx on twitter
Messages
1,921
Just found this old thread after waking up last night with high heart rate of 140 -150 bpm, probably caused by my first try at gentle water exercise yesterday (using kick board).

Hi @Mel9 -

I don't know if you have similar problems but in my case any type of exertion will make my sleep worse. And the more days in a row, the worse it gets!

So it makes sense that what seemed like a gentle exercise might have caused your sleep problems.

In my case it seems to be caused by my messed up autonomic system (POTS & NCS/NMH). So not only exertion in the traditional sense causes problems but also anything that triggers orthostatic stress. This includes tasks that require standing (or even sitting up straight for too long) and getting too warm (I get "too warm" at about 74 degrees F = 23 degrees C).

If I get enough rest days in a row then I can eventually reduce, although not completely eliminate, these sleep problems. And electrolyte solutions (Pedialyte or some similar salt/potassium/water solution mixed up at home) definitely help!
 

ryan31337

Senior Member
Messages
664
Location
South East, England
Apparently we have a major problem with oxygen saturation during sleep, and this can be measured. This new technology allows for continuous monitoring of blood oxygen saturation all night long during sleep (www.pulseoximeter.org/cms50f.html) for $112.

This can be done more cheaply with one of these for $35: https://www.amazon.com/Blue-Finger-Pulse-Oximeter-Sofware/dp/B00B8L8ZXE/ref=sr_1_1?ie=UTF8&qid=1490912117&sr=8-1&keywords=pulse oximeter usb

Won't be as comfortable as the wristwatch + flexible finger sensor for overnight monitoring, but good for a cheap test. There is nice freeware software called SleepyHead that interprets results.
 
Back