The Valve Area Index Calculation

[skeptic49]

I'm still heavily immersed in research, learning everything I can after seeing the surgeon for the first time last month. I go back to see him again in January after some tests.

One factor that has to be considered in assessing the severity of valve disease is your physical size. I found this out when I met with my surgeon in November. He told me that while my "numbers" fell within the guidelines for "moderate" AS, since I am "a big guy" that meant that my AS might already be severe. At one point during our meeting he sat down and gave some numbers off the top of his head to the RNP working with him and asked her to do some calculations. I didn't understand at the time, but I now believe he was doing valve area index (VAI) calculations.

Your VAI is your valve area in cm2 divided by your body surface area. In my case, as of my echo in August my AVA was calculated at between 1.1 and 1.4 cm2. My current body surface area is 2.35 m2. Plugging these values into the formula I come up with a VAI of between .468 and .595. According to the guidelines, anything less than 0.6 indicates severe AS. Even if I was at my ideal weight of about 200 (I'm 226 now), my VAI would still be severe or borderline severe at between .49 and .625. I'm a little fuzzy on what the surgeon said exactly, but it was something like they want to do the surgery if/when the number goes below .5.

There's a nifty calculator to determine your body surface area here.

Jim

 

[Cooker]

Very interesting ? I did not appreciate that when I hit the calculate button that it called me fatso ? according to this nifty calculator I need to lose 40 more pounds?. When I do I will contact the surgeon and see about updating my valve size?.

 

[Bina]

Jim, I go by whatever is on my echo report.
Before surgery my valve area was at .8cm and I was barely able to walk for more than a couple of minutes.

 

[skeptic49]

Jim, I go by whatever is on my echo report.
Before surgery my valve area was at .8cm and I was barely able to walk for more than a couple of minutes.

Bina,

Yes, but for us super-sized types...I'm 6'5 and weigh 226..the reality is that reaching 0.8 cm2 might mean that we'd never walk again...ever.

Cooker wrote:

I hit the calculate button that it called me fatso

ROFL

Jim

 

[Cameron]

Hmmmm....my valve area is at 0.6 sq cm and I still have very few symptoms. I am 6'2" and 240lb. AVR will be scheduled in mid to late January.
Cameron

 

[Lionheart]

Jim,
Thanks for the new info. I too like to understand and run the numbers. I always knew that the size of a person influenced some of the decisions about when to do surgery but I never knew that you could calculate a number and that there were guidelines.

I am about your height and currently about 205 lbs. About a year ago my cardio said it was time for surgery based on my Echo results. I later learned that my valve orifice area was 1.4 cm2. By Feb. when I was checked again at the surgical hospital it was 0.9 cm2.

I was about 210 lbs back then and from the formula my Body Surface area was 2.27 m2, thus when my valve orifice was 1.4 cm2 my initial VAI that called for surgery was 0.6 and a few weeks before surgery when my orifice was 0.9 cm2 my VAI was 0.4. At the time I had few symptoms except stress. I think my Cardio also based his decision that surgery was warranted on my left ventricle which had enlarged a bit since my previous Echo, unfortunately I don't have those numbers with me at the moment. I hope this helps.

Take care,
John

 

[zipper2]

YIKES

Oh what fun it is to ride in a one horse open sleigh LOL

Yep this was fun Jim...........LOL and interesting both then and now
surgery's.

zipper2 (DEB)

 

[ottagal]

Thanks for the info! From someone who is 5'1 and 105 lbs (give or take a few lbs), this calculation could work in my favour (AV measures .8cm2) I wonder if the indexing is automatically done by the cardiologist who submits the echo results? I would certainly hope so.

At my last cardio. appt. I brought this exact subject up (indexing for body mass) with my cardio. I was hoping he would say that I was really in the moderate category and not severe . His reply was that no matter what way I looked at it, he was still classifying my AV in the severe category when the other readings such as peak pressure gradient were factored in I don't think he wanted to get my hopes up and would rather err on the side of caution.