Originally Answered: What is thyroid ? What are the symptoms ? If untreated could it yield to enlarge of the heart or heart attack?
The thyroid is the gland found in front of your throat or trachea. It produces hormones that are necessary for metabolism of your body. Your thyroid can be hyperfunctioning (hyperthyroid) meaning it produces more than what is needed, hypofuntioning (hypothyroid) when it produces less than what hormon is needed or it can be euthyroid, it means you have enough. there is also a small gland located in the brain that stimulates or control your thyroid, so even if basically your thyroid is ok, if the pituitary gland is abnormal, it can cause your thyroid to either produce more or produce less hormones. The more hormones it produce, the larger the gland gets.
You had toxic thyroid, it means thay you have a hyperfunctioning gland. the problem with this is that the hormones produced cause faster metabolism, therefore you can have increased heart rate, increase metabolism of the body so weight loss, poor tolerance to heat and cold, tremors, etc. eye problems can also manifest, like proptosis or protruberance of the eyeballs.
You have to have your hormone levels check to see if its normal, whether you need supplements or anti-thyroid hormones. Your heart enlarges because the greater/faster metabolism exerts a higher toll in your body, increase HR, so the muscles in the heart are overdeveloped (just like when you do weight lifting, if you keep exercising the muscle, it grows bigger!)