Richard... Firstly regards that 17H before pain relief and especially when they knew the injuries you had... totall unacceptable (I'm a nurse and have had heart related issues with A&E ambulance visit in the past but more on that later) as well as that surgeon/Radiologist/Vascular Imagin Unit (I imagine) Dr who was retrieving the filter.
Regards both them things - and I spoke to a colleague yesterday who's also been inpatient for X problems - you need to get yourself in touch with PALS (patient advice and liason service). Its not a matter of just being "complaining" so you shouldn't feel that you are inconveniencing anyone.... They need to learn (and I understand how busy Southmead is as have done a few shifts there) as its still unacceptable.
How I ended up as inpatient (on coronary care unit) was after a 50 mile steep/fasted (during month of fasting and just before the fasting of the day ended). I used to vape alot (a very very lot) and used to smoke even worse before that, and they're definitely the culprits (thankfully I was forced to stop with this issue).
So after the ride and finishing my fast (with a vape straight after food), I went to the masjid (mosque - in case anyoje from the home office 'being british' dept is watching/reading) an hour or so later for the night prayers. These last around 50 minutes and unique to that time of year. After around 15 minutes I started getting shortness of breath (SOB) symptoms.
Thinking I'd eaten too much I finished my prayers midway during a unit - which is allowed as life/emergency takes preferance over prayers - and quickly hobbled home. Thinking I had probably eaten a bit much, I hobbled home (to have a poo) to try and ease the breathing situation. Whilst on the toilet I realised something wasnt quite right so called, as best I could, down to the missus to call for ambulance. Whilst awaiting them I sat myself on chair besides kitchen table and arms folded I leant and rested on the table. Sat upright (google Tripod sitting in COPD as its a good thing to know) to increase lung volume as best I could, I waited for the !!!

paramedics.
During that time I took some pain killers. They came and assessed. I had chest pain. They tried to leave me at home (even though I said "but I've got sharp chest pain... which I had by now and already informed them) but then decided its good to take me in (after i reminded them I'd got chest pain and I'd also read my ecg which they'd done and there were obvious changes in there that would need some sort of clarification... but I dont think I went as far as telling them that... they knew!). Asked them if I could have some pain killer, they told me they dont do such things (refere to my earlier slight substandard wording) but alloed me to go get my own. Not sure how I managed to get into the house and out again (gave myself some aspririn! Like you do)...
Got to hospital and was left im a cubicle in a and e. I understand, its super busy and I'm a young asian muzlamic (a term coined by one of Tommy Robinson chaps in a youtube interview

) looking chap who's obviously talking crap. My pain crept up and up over the course of that half hour or maybe an hour. Excruciating and not wanting to bother them I did what I knew. Read a certain chapter of the Quran* which is reported (field reports over the years I believe and they've worked for me in past) to relieve pain. I was crying by this point.
I imagine someone in the dept must have said to someone else "will you shut that #$%k$r up will ya before we have the anti-terro squad all over us". I couldn't really care less by this point and it was helping. Few minutes later as if by magic, someone turns up with more pain relief than you can shake a stick at (including Morphine which would normally make me sleepy I believe... again from field reports of the prescribed 30mg Codiene).
Aftet that and blood results being back. I got told about the blood results. That I could be admitted. I obviously (like you do) said I'd go home and come back to the Ambulatory Care Unit in morning. Troponin (a cardiac muscle marker which shows distrubance around there) was about 15 at this point which for my limited knowledge was just/could just be a bit of muscle disturbance.
Next day I went in and after sending and recieving my blood results, suddenly the full cardiac team was all over me. Told me my Troponin was 2000 (massive heart attack territory). I told em I'd come back for further tests (as you do) and the specialist cardiac nurse, had a word

and I was sure they'd be retaining me anyway...
To end it all (the story for now, noy the episode which turned out not as bad but bad enoigh) I ended up in Coronary Care unit. Had an infection or inflammation or both around the outer layers of the heart (perimyocarditis... inner layer is endocarditis which is IV drug users get after lots of dirty abuse and is almost always one or two steps not far from deaths door). Got put on Ramipril (a heart failure drug... which I didnt take... dont try that at home and I'm only telling it now). Heart rate overnight on CCU was in the 40 and I think as low as 35.... I just enjoyed being in Chris Froome/the hardcore Eddy Merckx (who was reported as being as low as 30s or lower during rest as his hesrt was that strong) territory. But my normal resting heart rate is around 60 and 70...
*Suratul Haqqah (chapter 69: The Imminent Happening).
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That was over 2 years ago now (ramadhan of 2017 I believe). It was around 6 months before any cycling after heart scan csme back clear/clearer, and around 12 months before risking another 100 miler and 24 months before I tried another fasted ride

).
So what do I do now:
Well Im constantly at risk of chest infection (and have IMO successfully overcome a pneumonia at home: it was a rather painful few days) and I also take my csrdiovssculsr risk very seriously (without becoming paranpid and bothering the doctors/hospitals):
I have honey as its described in the Quran as
Your Lord reveiled to the honeybee: " Make homes in the mountains, in the trees and in the structures they raise (68) Then eat from all the fruits, and go along the pathways of your Lord made easy for you." From their bellies comes out a drink of various colors in which there is cure for people. Surely, in that there is a sign for a people who ponder. (69) [chapter 16; Surah Nahl/The Honey Bee]
Here comes the science bit (and why I know how to use it and yes, some of the better hospitals do use it as a wound dressing and yes, it is used in the community by nurses on wounds... but it can be painful... and yes, I do use it on my saddle sore risks and yes it does work rather well... mainly I use it to decrease the risk of infections of chest as I reckon them 20 years of smoking (40ish pack years if not more) did catch up with me.

Thats an old article but it would always fascinate me (the health sciences from the Quran and hence my pathway chasing a nurse/paramedics career)... if anyone wants me to post pics of the actual article just say...
So thats how i manage the infection side of things. The way I manage the cardiovasular/cholesterol risks is again from the nursing mags but caught/stayed on my mind from the Quran. Allah swears an oath in the Quran 'by the Olive' and in the nursing course I learnt bout the olive oil and how it gets rid of the bad cholesterol and keeps the good (high density lipoproteins being the good and low density being the bad)...
So I often have a spoonful/raw and it really is remarkable. Its how they (I've not really kept up with evidence bases in this dept as much as I should have) explain why the Mediterranean diet helps with reduced heart attacks and strokes (the Greeks are generally a bit 'round'and eat well... but they drizzle olive oil
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Anyways... Richard. Hope that helps buddy and this in no means a way of saying "dont take your drugs" as I'm not a doctor (just a bog standard nurse who's not really very clever but just gets fortunate here and there with the info falling in my lap). Just might help (especially the honey and i reckon everyone should be having honey in diet... drug companies probably wont be hapoy but antibiotic resistance would probably go down
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Most importantly, keep smiling (must keep cup half full and not half empty) and pushing forth. Which it looks like you're doing... PALS (if you wish.. dont forget!)