Dear Charlotte, thank you for your question. Your history is complicated, but I think there are a few areas to comment on. First, the atrial enlargement and left ventricular hypertrophy are most likely caused by hypertension even though you state that your BP is usually normal. Thus, I think you should check your BP frequently and seek treatment if it is consistently > 130/90. Second, your hypothyroidism is appropriately treated since you now have a normal TSH. I'm not sure why you had edema before treatment for hypothyroidism but you don't appear to have any left ventricular dysfunction, so that certainly would not be the cause of the edema. Third, if your thallium treadmill test was normal, then I doubt that you have any coronary artery blockages. However, the only way to definitively rule out blockages is to have a cardiac cath which is an invasive procedure that does carry some risk. Fourth, your elevated LDH is not specific for any disorder and probably doesn't mean much. Finally, I doubt that you have a deficiency in atrial natriuetic peptide (ANP). ANP levels are rarely measured clinically so I wouldn't suggest pursuing that line of inquiry. Thus, it may help for you to see your cardiologist again and you may want to discuss the option of undergoing a heart cath.
I hope this information is useful. Information provided in the heart forum is for general purposes only. Only your physician can provided specific diagnoses and therapies. Feel free to write back with further questions. Good luck!
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