Monday, July 15, 2013

Aortic Valve Stenosis

I am learning so much about this subject!  It appears that a small percentage of the population has a bicupsid aortic valve (BAV) instead of the more common tricupsid form: 1-2% of the population.  But the majority of aortic valve stenosis (AVS) patients 15 to 65 have bicuspid aortic valves, and AVS appears on average two decades younger in BAVs.  It seems to have a similar mechanism to atherosclerosis in how it develops, with calcium deposits eventually stiffening and apparently destroying the valve.

There is a particular mutation associated with the disease, and that isn't surprising, because the BAV issue also seems to be inherited.

My cardiologist decided to do an adenosine stress test, instead of the more typical exercise stress test.  This article from 2001 gives a pretty clear explanation of why:
RESULTS Eight patients developed dizziness during exercise testing but made a rapid and spontaneous recovery. No other complications of exercise testing occurred. Survival curves, with or without the occurrence of end point events for the variables studied, showed significant differences for positive versus negative exercise testing (p = 0.0001) and aortic valve area < 0.7 cm2 v⩾ 0.7 cm2 (p = 0.0021). There was no relation between the end points and transaortic gradient (p = 0.6882). In multivariate analysis, a hazard ratio of 7.43 was calculated for patients with a positive versus a negative exercise stress test. Although asymptomatic in daily life, 6% of the patients (4/66) experienced sudden death; all these had a positive exercise test and an aortic valve area of ⩽ 0.6 cm2.
Yes, 6% of the patients suffering sudden death is an argument against exercise stress testing, I would say.  (Note that it doesn't say that they died during the test, or because of the test, but no previous symptoms and die afterwards is not good.)

There seems to be some evidence that there is an inflammatory response relationship with aortic valve stenosis, and that may be why statins seem to delay (although not reverse) the increasing degradation.

I suspect that when I first started having problems breathing when exercising in cold weather about five years ago that this might have been an early sign that things were not going well with that valve.

1 comment:

  1. Clayton, I read that to say that 6 experienced sudden death some time after the positive test, not as a result of the test.

    BTW, may I suggest changing your commenting system to Disqus. Half of my comments get lost due to various flakinesses in the sign-in process.