Evidence from clinical trials now indicates that in patients with stable angina, medical treatment can be as effective as the more invasive treatments we hear so much about, treatments like bypass surgery, angioplasty and stents.

But what, exactly, is medical therapy for angina? It turns out that treating angina medically is an art that involves the judicious use of several treatment modalities, some of which are well-known to doctors and others less so. You can read all about the medical therapy of angina here.

Atrial fibrillation is one of the most common cardiac arrhythmias - and unfortunately, it is of the most difficult to treat. Here is a review of atrial fibrillation, its causes and consequences, and the options for therapy.

New evidence has been found that Cardiac Syndrome X (angina with normal coronary arteries, most often seen in women) is due to a disorder of the small cardiac blood vessels. Read about it here.

A new study appearing in the Journal of the American College of Cardiology suggests that individuals whose thyroid tests indicate they have subclinical hypothyroidism are at an increased risk of developing heart failure over the next several years. Furthermore, it appears that the heart failure they develop is likely to be diastolic heart failure.

Subclinical hypothyroidism is a condition in which the thyroid gland is having trouble producing enough thyroid hormone, so the thyroid gland requires higher levels of "thyroid stimulating hormone" (TSH - the hormone that "whips" the thyroid gland into doing its work). In patients with subclinical hypothyroidism, the actual amount of thyroid hormone in the blood is normal - but levels of TSH are elevated. Previous studies have suggested that patients with subclinical hypothyroidism have a higher risk of heart disease. What is new about this latest study is that it identifies subclinical hypothyroidism as a potentially important cause of diastolic heart failure.

In diastolic heart failure, the pumping function of the heart is largely normal, but the ability of the heart to fill with blood before it pumps is impaired. Doctors have been puzzled about the cause of diastolic heart failure. The possibility that subclinical hypothyroidism may cause diastolic heart failure is an attractive one. First, it turns out that the kind of people who develop diastolic heart failure - middle aged or older women - are the same kind who tend to develop subclinical hypothyroidism. And second, subclinical hypothyroidism is a treatable condition. (It is treated the same way that "clinical" hypothyroidism is treated - with thyroid replacement hormone pills.)

At this point, it is not proven that subclinical hypothyroidism causes heart disease. However, the evidence grows ever stronger. Women whose TSH levels are 10.0 mIU/L or higher should certainly discuss with their doctors whether treatment is in order.

You can read more about the thyroid and heart disease here.

You can read more about thyroid disease here.

_Sources:

Rodondi N, Bauer DC, Cappola AR, et al. Subclinical thyroid dysfunction, cardiac function and the risk of heart failure. The Cardiovascular Health Study. J Am Coll Cardiol 2008; 52: 1152-1159.