The Nation's Health + [inflammation]

Your enlarged aorta

The thoracic aorta lives happily within the chest.

The aorta is the main artery of the body that emerges from the heart, located just under the sternum. It is the "tree trunk" from which all the major arteries branch off to the rest of the body: the arms, brain, abdominal organs, pelvis, and legs. The aorta receives the high-pressure blood ejected directly out of the heart muscle.

However, there are evil forces in the body that work to weaken the aorta. When the aorta is weakened, it enlarges. Enlarged aortas also tend to grow atherosclerotic plaque. Plaque in the aorta poses long-term risk for stroke and and mini-strokes ("transient ischemic attacks," or TIAs), due to fragmentation.

There are many enlarged aortas in this world. I see at least several every week. It is fairly common, particularly in people with high blood pressure and cholesterol abnormalities, as well as those who are overweight. Smokers get it really bad.

Conventional thinking is that, once an aorta enlarges, it will inevitably continue to enlarge at the average rate of 2.0 mm per year (resulting in 1.0 cm enlargement over 5 years). For this reason, conventional discussions on the topic of thoracic aortic aneurysms all say something like "Enlarged aortas should be monitored yearly. Surgical replacement should proceed when the aorta reaches a diameter of 5.5 cm."

This is because an aortic diameter of 5.5 cm is associated with much greater likelihood that the aorta will rupture (fatal within minutes) or the internal lining will tear, a "dissection." The surgery is a major undertaking that involves opening the chest and usually replacing the aortic valve and inserting a synthetic aorta. The procedure is high-risk, especially if any branch arteries are involved.

So putting a stop to any further aortic enlargement is a worthwhile goal. Unfortunately, conventional thought is that there is nothing you can do to stop the inevitable growth of the thoracic aorta.

Nonsense. There are a number of efforts you can make to halt further increase in aortic diameter. (My experience in this is anecdotal and unpublished, but now numbers several hundred patients.)

There are two categories of factors that cause the aorta to increase in diameter:

1) Internal pressure--Think of blood pressure as the internal inflating pressure on this "balloon." Keeping the "inflating pressure," i.e., blood pressure, low exerts substantial effect on slowing growth of aortic diameter. I aim for normal BP or lowish BP (less than 130/80, preferably 100/70).

2) Factors that weaken the aortic wall--Processes like inflammation, glycation, lipoprotein deposition, and nutritional deficiencies will serve to weaken the supportive tissue of the aorta. For that reason, correction of lipoprotein abnormalities (e.g., small LDL and lipoprotein(a)), reductions in carbohydrate intake and thereby blood glucose/glycation, and "normalization" of vitamin D, vitamin C supplementation (for collagen crosslinking), and omega-3 fatty acids all play a role.

To push even farther, there may be additional advantage to following strategies that impair the production and activity of a crucial enzyme that lives within the aortic wall: matrix metalloproteinase, or MMP. MMP degrades the collagen and other supportive tissues within the aorta, weakening it and permitting expansion. Blocking MMP may prove to be among the most powerful new strategies to halt aortic expansion.

Compounds that have potential MMP-inhibiting effects include:
--Vitamin D--A substantial effect
--Resveratrol--One of the polyphenols from red wine
--Doxycycline--This old antibiotic often used for acne treatment has, in preliminary studies, shown important MMP-blocking effects and slowed aortic expansion.

Anyway, there you have it. A bit complicated, but a "recipe" that has failed me only rarely.