So the vast majority of CIMTs that patients bring in to me are really bad.
Though I think the absolute worst one was last week. A patient brought a CIMT
where his local radiologist told him, "Yes, this is a CIMT." It wasn't even in the
neck. It was a lower extremity ultrasound, so it wasn't a media thickness test and
it wasn't carotid. It was awful.
So Michelle and I are continuing to work on various ways to get you guys
access to better CIMT. As I've said, I've worked with several providers in
the country. Todd's group is by far the best. He's
developed national access. There are a couple of others. I still use a guy, a
neurologist named Fred Callahan in Nashville, Tennessee, And there's a group
in LA that occasionally does a good job. Again, we're going to be coming out to LA
in September to provide you what we know is high quality CIMT. But why all the
problems with the quality of CIMT? That's actually what this video is gonna
be about. I published a video that covered this a few months ago but a
couple of things happened inadvertently. That video got linked to another one
which was totally unrelated. We're looking to see if we can edit that out.
It got a thousand views so you may have seen some of this already. If you have
and it's repeat for you, just be warned and just wait for the next video. But I
think one of the problems is it made it a thirty minute video when it's really
only five to ten minutes. So I'm gonna do a quick video for folks that haven't
seen it and folks that were put off by the inappropriate little long length.
Anyway, so what is the purpose, what's the goal for a CIMT? It's to help patients
visualize what's going on in their arteries and again I won't go through
the details on this. But you see going from left to right you're getting more
and more and more increase of the plaque process in your arteries. This doesn't
happen in the arteries of the neck and head without happening everywhere else.
So I still get patients comment to say, "Well, that's just in your neck. That's not
in the heart." Your arteries are your arteries. They pump the same blood. I mean
every minute blood goes through can make the trip throughout the whole body.
So what's going on in one bed... artery bed is in
another. So what are the problems? Actually, there are more than one problem
with CIMT. The biggest one is technologists technique and it has to do
with what I call the problem of "perspective." I'll get what does that
mean. I'll get to that in just a minute. There are other issues as well.
Standardization of reporting in the research has led to a bunch of really
bad CIMT studies. Getting into the research, when you look at the
groups that do it well...and again Tod's is not the only group, is the only one
that provides national access. There's several academic groups and a
couple of others that I've mentioned that do provide local access where you
can get a good CIMT. And when you get a good CIMT, it's better than anything
else because of the problems with the standardization of reporting in the
literature. The standards committees looked at the literature of a science
and said, "This doesn't work. That's not standardizable." Well, it is again in
the right hands. Now let's go back and talk for a minute about this issue with
the problem of perspective. Let me actually go to a picture and you may
recognize this picture. If you saw... if you're one of those thousand people that
saw the original video a few months ago, this is creating a... this is a
photographer obviously creating an optical illusion. It looks like the boys
are as big as the Eiffel Tower. They're not because they are just way way closer
to the camera. So how does that what does that have to do with plaque? We'll go to
that in just a sec. But here's the thing to remember. Plaque is not uniform around
the circumference of the artery wall. Some of its thin, some of it's I've got
thinks on of it, some of it's thick. So again, perspective matters. Now as you
begin to look at these, you can get some again perspective on this issue.
These are cross-sections of arteries. The red part is the muscular layer, the
media. The intima is this tiny, thin layer here. But then everything in between is
the is plaque. And as you see here, this
is liquid plaque. Now this is fairly uniform. But still, even this one, if you
took a cross-section through here, if you're shining the ultrasound waves
through here, you're gonna... you get the back end... the opposite.... the opposite side
of the artery that you're coming in from. So if the technologist is coming through
here, they're going to get this thickness. On the other hand, obviously, if they're
coming through if they were coming through here, they're gonna get a thicker
amount. Now you don't really have that much ability to mess this up but you
do have some and it is significant look at this artery for example huge amounts
of plaque on this side. So for example, if the wand came in through here,
you'd get this much plaque. If it came in through here, you get a much bigger
amount. And obviously, if it came in through here, you might get much less or
nothing at all. And yes, you will routinely see plaques
that have been missed again. Even with the problems with CIMT, if you get a
good one, a good high-quality CIMT, it tells you so much more than any other
measure that we have. This is just again another look at a real live artery and
we'll go in and look at some others in just a second. As you see, this was soft
plaque that's no longer soft anymore. It has broken through the intima layer
and a clot has formed, this black thing. The majority of that clot broke off and
went on to cause the heart attack which killed this patient. But again, as you can
see here, this is the media, this clear white looking area, that's the intima. And
then so that's the plaque, so much less plaque. If you had come in from that side,
much more plaque. If you came in from over here, and again more plaque. If you
came in from this perspective, another artery which again shows a significant
variation. And again the potential ways to miss plaque if you're coming in
from a HD IMT. So again, as you might say, "Look, this is awful. This is
terrible." Let's get back and think about the alternatives. The most commonly used
alternative is a stress test. It doesn't see anything at all unless there's over
50% occlusion and it has all it has up to 30% false positives over that many
false negatives because 68% of heart attacks occur in people that have less
than 50% occlusion. So by definition, those people are going to have a false
negative stress test. We say, "Well, let's go to get a calcium score." As many
viewers have pointed out, calcium score measures only calcium. And plaque like
this, that's soft, that is likely to rupture and cause a heart attack, doesn't
have calcium in it. So that would not show at all
on a coronary calcium score. Now to get a little bit more perspective, here's the
model of a carotid artery and obviously in a dummy and you can begin to get a
little bit more vision and as I'm using obviously and talking about maybe my if
my hand were the one the ultrasound wand. I've trained some in doing these. I'm not
very good at doing them, but as you can see, you've got to know exactly which
level to get the carotid bulb. You've got to know whether to come in from this
side versus this side. And again, that is a significant variation when you begin
to think about the variation that you can see in those arteries. Bottom line is
it is not easy to get a good picture of plaque. You've got moving arteries and
that's a problem with things like CT (computed tomography angiogram). It's also
a problem with other items as well. You've got moving arteries. You've got
plaque that is not uniform in terms of its coverage around the circumference of
the artery. You've got the fact that arteries in the chest are behind bones.
And you've got the fact that blood flow measuring blood flow like using
something like a stress test doesn't work because you get plenty of blood
flow even though they have significant amount of plaque
and plaque that can cause a heart attack and stroke. So hopefully, that helps you
get some more perspective on CIMT the problems of CIMT, and how those compared
to other methods of understanding and measuring screening for plaque. If you've
made it this far, thank you very much for your interest. This is Ford Brewer. I started
off my career as an ER doc. And that can be frustrating because most of the
things bringing patients into the ER can and should be prevented, like heart
attack and stroke. So I went to John Hopkins for training in prevention. Did
well, ended up running the program, trained dozens of docs there, and have
trained hundreds and even over a thousand doctors since then in
preventing disease. What's even more important is I've helped thousands of
patients prevent heart attack and stroke rather than waiting for the devastation
and hoping for a cure.