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Date of last update: 10/20/2017.

Forum Name: Cardiology Diagnostics

Question: Hyperthyroid/Left Bundle Branch Block

 Capistrano - Sat Sep 19, 2009 4:55 pm

I am 63-years old with no previous history of serious illness other than a complete hysterectory over twenty years ago and slight arthritis in my knees. My husband has had two open heart surgeries so we take our blood pressure at home quite frequently.

Several weeks ago I noticed my ordinarily perfect blood pressure was rising very slightly and my pulse was strangely high. I attributed the change to stress and sleep deprivation at that particular time. When my numbers continued to rise, I got worried and went to a doctor. By then I was feeling lethargic fatigue like nothing I'd ever known in my life and I was becoming deeply depressed.

My doctor said I'd been O.K. a year ago, my lab numbers had been good, etc., but when she did an EKG, she said I had Left Bundle Branch Block. She made an appointment for me to see a cardiologist and scheduled routine lab work. I ended-up seeing the cardiologist one day after getting my lab results back - they showed I was hyperthyroid. The cardiologist said my LBBB might be connected to the hyperthyroidism and for me to finish a couple of other thyroid tests and then he'd do some heart tests.

I had a nuclear thyroid scan and ultrasound. The results showed small nodules on my thyroid but the doctor said she didn't believe my symptoms were related to hyperthyroidism. She almost became angry when I said I'd been researching hyperthyroidism online and fatigue was always a symptom. She totally disagreed and seemed to lose interest in treating me - she said I should return to the cardiologist because fatigue, elevated blood pressure/pulse and slight pain in my neck were womens' symptoms of heart disease, not hyperthyroidism.

I have waited almost a month but next week I will have a "nuclear" stress test and echocardiogram. At this point, I am now so fatigued that I'm wondering how I'll be able to do a stress test but I guess the cardiologist will understand. It's hard for me to even get a bath and get dressed without feeling totally exhausted. I am having major palpitations now, often feel faint, cannot do much of anything really. I feel like my normal life has stopped because of such intense fatigue.

In the research I've done, in all sincerity my symptoms match HYPOTHYROID more than hyperthyroid...almost without exception. Is it possible that hyperthyroid can somehow be mistaken for hypothyroidism?

Also, do you think LBBB can be the reason for the thyroid symptoms?

I feel like I am being totally misdiagnosed but I'm looking forward to the heart tests. The cardiologist seemed so sure that my LBBB was caused by hyperthyroidism but my internal medicine doctor seems just as convinced that it's the other way around.

Thank you for any advice or information you can share. I'm so totally frustrated and want so desperately to feel well again. I care for my 88-year old mother and I need to get my strength and stamina back.
 John Kenyon, CNA - Sat Oct 24, 2009 10:27 pm

User avatar Hello -- This post calls for several conclusions. First, you may need to change doctors because you have encountered one who is deeply bothered by patients who insist in being their own advocate. This is something that's changing and will continue to change,but there will remain some doctors who resent the patient getting involved in the detective work -- and sometimes they are justified, but it doesn't sound like this is the case with you at all. There are also doctors who really appreciate informed patients, because they can help the process move forward and will mention things other people might never think to mention. So there's that.

You're also correct in that your symptoms do sound a good deal more like hypo- rather than hyperthyroidism, and sometimes, early in thyroid disease the two can become confused or even change back and forth before one assumes the dominant role.

That being said -- and it does need following up because the nodules are there and most certainly could be involved in this business -- your having LBBB is not all that likely to be caused by either hyer or hypthyroidism, and it does often show up in relation to other heart issues which can cause the sort of symptoms of which you're complaining, so this does need to be followed also. Your doctor is correct about that part, but not in the attitude toward your invovement in your own healthcare. My opinion only, but I tend to think my opinions through pretty thoroughly and have been in the business a long time. The LBBB is worrisome (unlike RBBB) and there are a number of potentially related heart issues which do need to be ruled out as the underlying cause, even as the thyroid problem, whichever it is, also gets followed. While you do need to be followed by the cardiologist, you might be able to avoid an awkward pass with your doctor by arranging a consult with an endocrinologist to work out exactly what's going on in the thyroid department. If your internist is required by your health insurance to issue referrals you may have to either self-refer or as I've suggested, perhaps change internists. This is too serious to just brush off half of what's already been demonstrated to be present (the thyroid issue). If this is causing the LBBB (something possible but not that likely) then great, you'll get the thyroid issue managed and that will go away. If, however, they are two separate issues (comorbidity is the term used for what I call the Horrible Coincidence Phenomenon), they both need to be managed, and you'll need a sympathetic internist or GP to quarterback the care by the specialists.

I hope this is helpful. Good luck to you and please do keep us updated.

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