When I was a very small child, a combination of my bad hearing and an obsession with ponies meant that I thought the classic Yes song Owner of a Lonely Heart was actually called Owner of a Lonely Horse. Ah, the folly of youth.
As the years went by, I became increasingly good at distinguishing between the hollow muscular organ which pumps blood through the circulatory system, and the large solid-hooved herbivorous ungulate mammal. No doubt this helped enormously when it came to talking to the doctors about my heart problems. Anyway. At the end of my previous post on the subject of my lengthy road to diagnosis, I had left my local hospital's A&E department with a heartrate of 140 and no explanation...
The next day, I went to my GP, who prescribed beta-blockers. Going through my symptoms (rapid heartrate, tremors, fatigue, hair loss, etc) it seemed that thyroid problems were an obvious possibility. I'd had my thyroid levels tested at A&E and they came back fine, but my GP checked again. They were still fine.
And that was the problem: in fact, my levels of thyroid hormone (free T3 and T4) were much too high. But when doctors suspect you have too much thyroid hormone - hyperthyroidism - that's not what they look at. Instead, they test your thyroid-stimulating hormone (TSH) levels. Low TSH implies hyperthyroidism (because your body is trying to lower your thyroid levels by producing less TSH) while high TSH implies hypothyroidism (because your body is trying to increase your thyroid levels).
Unfortunately, my TSH level was within normal ranges, even though the whole time I had a tumour sitting on my pituitary gland, giggling frantically to itself and oozing TSH with the enthusiasm and verve of a naughty child left unattended with a box of felt tips and a newly papered wall. It was on the high end of normal, but without measuring the T3 and T4 you'd never realise that it was too high for my body. I should point out at this stage that I don't blame my doctor for not doing the other blood tests. A pituitary adenoma producing TSH (a.k.a. TSHoma) is a one in a million illness.*
It's not my doctor's fault that he didn't recognise how incredibly special I am.**
So the next obvious possibility was that my sinus tachycardia (rapid heartrate) could be due to - gasp - a heart problem! And boy, did they ever check me out. I wore 24-hour heart monitors on several occassions - once I was wearing one when I went to a formal dinner, and had an interesting half-hour beforehand trying to find a way to conceal the bloody great thing using only a lace bolero and my native wit - and I had an ultrasound scan of my heart. Ultrasound heart scans are pretty cool to look at, but I can't help thinking that they must be more fun for men, who (in most cases) don't have boobs. Boobs are not usually a problem, but they aren't half inconvenient when someone's trying to use The Power Of Sound to examine the circulatory organ located somewhere beneath one of them.
After six months I finally got to see a cardiologist. He told me that I didn't have a heart problem, that it was almost certainly hormonal and I should have further blood tests, and that I should stop taking my beta blockers.
Two out of three of those statements were correct.
I'm still not entirely sure why he ordered me to stop taking my pills immediately, when every other doctor I've seen since has emphasized the importance of coming off beta blockers slowly to prevent rebound tachycardia. And equally, I'm not sure why I didn't protest more. Regardless: I came off the beta blockers, spent a week feeling as though walking across a room was a labour worthy of Hercules, then angrily phoned the cardiology department and insisted that I was going back on the bloody medication.
But despite this slight hiccup, progress had been made. The cardiologist had ordered the right blood tests. I was referred to endocrinology...
UPDATE: You can click here to read about how I finally got a diagnosis. Or click here to go back and read about my first trip to hospital.
*In fact, a friend of mine who's a medical student told me that one day, when a group of med students were med studenting, a patient's symptoms were described and they were asked for possible diagnoses. One girl suggested a TSHoma. The doctor's response: "Don't be ridiculous, that never happens." I asked my friend if she stepped in to mention that she knew someone with a TSHoma. She did not, apparently because the girl who suggested it as a diagnosis was a bit of a know-it-all and was overdue a put-down. Of such fine things are doctors made.
**Interpret "special" as you will...