aortic root 4.2 (no BAV) growth rate???

[ElectLive]

In your experience, is there a difference in echo VS CT without contrast for aortic root? My echo (read) by the same cardio have been very consistent. 4.2, 4.1, 4.2 and 4.2 at the root. The 2nd to last 4.2 was read by someone else as a 3.7 but as stated the 2nd cardio whom did the 1st 2 said he sees a stable 4.2 across all the echo’s. The CT showed a 4.38 at the root without contrast. I was told if I did contrast that may have gotten 4.2 (would have measured just the contrast area) as well as the CT can give larger dimensions due to imaging a moving target as well as the CT # is most accurate…

Chris - Thanks again. You know, my own set of measurements were identical. Interestingly, the measurements themselves are usually not 1 to 1, in other words, echo is internal diameter and CT is external diameter, but as you might guess, it normally doesn't make much of a difference, except sometimes at the descending aorta. I think the only real need for contrast is diagnosing issues of the aorta tissue, such as dissection, it doesn't really impact size measurements much, but the cardiologist's comment makes a lot of sense in that regard, thanks for sharing. For the aorta as a whole, CT and MRI are more accurate, but they come at the expense of being more invasive and expensive, so they are not the initial preferred method. But as I said in the other thread, the root seems to be one place where echo deficiencies are not really true. There is a long discussion in the Aorta Guidelines, referenced above, that describes the pros and cons of each method, in much more detail than my comments.

 

[ElectLive]

I just happened upon this by accident but found a great visual aid to help clairfy the what's "normal" for aortic root discussion. As mentioned earlier, age and body size are key determinants of size. Both the Aorta Guidelines and the American Society of Echocardiography reference a 95% confidence interval for aortic root size at the sinuses of Valsalva in a large reference population. An aortic root diameter above the upper limit of the 95% confidence interval is considered dilation. The best source for this explanation is here: http://www.asefiles.org/ChamberQuantification.pdf and here's the graphic:

 

[chrisc]

Thanks, nice read...

I have a BSA of 1.9 (5'11" @ 170#). At 35 that puts me at a 3.7 root max... I notice that article is from 2005 and a doctor had told me that normal aortic root measurements had changed (max got smaller). I assume some time between 2000 and today. Then I also heard they may increase the normal range max again.

Anyone have any facts on that?

 

[Roxx]

I have heard the same thing Chris..... i know in the old days with cardios, unless a person was in that 4.5+ area, they hardly even brought it up.

 

[ElectLive]

You know, "normal" seems to always be in a state of flux. I've seen numerous studies indicating that "normal" should either be higher or lower. Both of the Guidelines mentioned above are current, with the Aorta Disease Guidelines very new (2010), and they reference the same 95% interval indicated above. So, I'm not aware of an "official" change, but certainly I wouldn't doubt that it may exist in some form. There are multiple entities in play, and it's certainly worth noting that the various size "standards" commonly referenced come from different sources.

Now, the management of patients is definitely changing, spurred on by the 2010 Guidelines, and by John Ritter more indirectly. More proactive diagnosis and monitoring and earlier intervention are the recommended new standard of care. Also important, absolute size is not the only emphasis of the Guidelines, it's the multifactorial nature of aorta size that is addressed instead. In some ways, it's easy to get caught up in analyzing size and what it means, when a more primary cause of aorta failure, genetic disease, is often more important. Dissection can occur at perfectly normal aorta sizes in those with genetic syndromes and tissue disorders. I saw a retrospective study done by my surgeon and his colleagues that documented aorta size in patients who presented with emergency dissection over a 10 year period. The range of values was shocking both on the low end and the high end.

But one of the best stories I've heard about all of these issues is that John Ritter's older brother, Tom, was diagnosed with an aneurysm after John's death and underwent successful aorta repair surgery. So, while aneurysms can be a scary thing, it's important to remember that a large majority of the tragedies are likely patients who were previously undiagnosed. Yes, it can easily lead to extra worry on the patient side of things, but I think it's definitely good news that more and more doctors are being proactive at an earlier stage.

 

[chrisc]

about 3 weeks ago i submitted a saliva sample for testing which is stated to pick up on any genetic issues of causation (at least those we know of anyway). i should call soon to get those results, they should be in shortly i would imagine. the technology we really need is a non-invasive way to measure with a high degree of accuracy, the wall thickness of the aorta. i believe that would be pivotal. granted a direct correlation of wall strength cannot be derived from thickness, but is seems like great info to me...

one thing i am curious of and i am unsure if 'll know in my life time, is invasive medical action taken earlier then needed in some cases? are some folks pulling the surgery trigger on an enlarged root or aorta early? and my question is not exclusively in regards to aortic issues, for example, there appears to be a shockingly higher number of women electing for mastectomy prophylactically, and i wonder what % of those women would have lead normal lives without any cancer issues sans mastectomy.

 

[Roxx]

Chris thats a good question. My best guess on heart related repairs is that one should try to get by as long as possible with their god given original equipment, as once a successful surgery occurs, the clock starts ticking on the age of that equipment. Of course, one shouldnt wait so long to damage their "original equipment" that will be staying either. I could be wrong, I am a amateur, but this idealogy seems most logical to me.

 

[ElectLive]

...is invasive medical action taken earlier then needed in some cases? are some folks pulling the surgery trigger on an enlarged root or aorta early?...

I guess it depends on your definition of early. If not an emergency (acute dissection or rupture), then any scheduled aorta repair is technically elective and "early". That's probably not what you mean, though, I assume you are probably referring to choosing to operate at increasingly lower diameters, or even before the threshold indicated in the Guidelines. One obvious group is valve patients, who often have aorta repairs done early at the time of valve replacement. It wouldn't have ordinarily been done but if/when the additional risk impact is minimal, it obviously makes perfect sense to take care of it at the same time. But maybe that's not exactly "early" either.

Over time, surgical thresholds have been determined through study of previous outcomes, and several sub-groups of "early" have been establised. 5.5 cm is a surgical baseline of sorts, with no other factors in play, but when dissection has been shown in studies to occur at lower diameters (than baseline) in certain sub-groups (Loeys-Dietz syndrome seems to be highest risk), surgery is recommended much earlier (4.2 cm for L-D). Bicuspid valve disease, which many here have, is another "early" sub-group. But historical data only mean so much, surgical risk also has to be factored in. Generally speaking, most surgeons only operate when the risk of the surgery is less than the risk of adverse events of dilation/aneurysms left alone and/or treated (if time allows) in an emergency setting.

The problem of course with aorta issues is that dissection and rupture are dramatic and unexpected. So, if you wait as long as possible, say until a patient reaches the mean dissection diameter, then there's a 50% chance the patient would suffer potentially catastrophic damage before even reaching the OR. Aorta failure and valve failure (pretty gradual overall) are two very different things, waiting as long as possible for aorta repair is a recipe for disaster. The good news, though, is that aorta repairs are generally without a fixed lifespan, though, unlike bioprosthetic replacement valves.

The retrospective study evidence of my surgeon and colleagues was used to suggest that the baseline maximum surgery threshold be lowered from 5.5 cm to 5.0 cm - particularly in hypertensive patients at high volume centers. So, yes, they are proposing early. They compared outcomes of elective procedures versus outcomes of emergency procedures (those that made it to the OR) as well as evaluated the mean dissection diameter of the acute cases, and the evidence is pretty compelling. But there will always be some risk to the surgery too, so there is a limit to how early is clinically reasonable. Mild aorta dilation can be normal for quite some time and stable diameter in the absence of other risk factors is best case. So, having said all of the above, it would probably be hard to find a surgeon who would recommend early intervention under mild, stable, and limited risk circumstances.