Thanks for joining me
on this discussion of abdominal aortic aneurysms
in the section of vascular surgery.
This is a particularly important topic.
So, I hope you pay close attention.
There are lots of risk factors
for abdominal aortic aneurysms.
We’ll call it AAA going forward.
remember the other vascular lectures?
Smoking is a bad player
in all vascular diseases.
Certainly, there's a male preponderance.
And as we get older,
most of our abdominal aortic
diameters actually enlarge a little bit,
but not necessarily aneurysmic.
High blood pressure and non-laminar flow.
There is some suggestion
of a family history
and perhaps there's a genetic component,
although we’re not exactly sure why.
And history of any
other peripheral aneurysms.
This is true of all patients with aneurysms.
As we say,
once you have one aneurysm,
you might have an aneurysm elsewhere,
so you should have a high index
of suspicion to look for other sites.
And like many of the peripheral vascular diseases,
history or the actual presence
of coronary artery disease
and other atherosclerotic sclerotic disease
also, of course, puts you at risk for AAA.
Here's a quick review of
the normal anatomy.
Take a look at the picture
in the center of the screen.
The red is actually the aorta.
Remember, the aorta is to the
left of the inferior vena cava.
It's, of course, a little closer to the
midline of your abdomen than the IVC.
Also, clearly shown here
are the superior and
inferior mesenteric takeoffs.
You also note very clearly
the common bifurcation.
Now, what’s the definition
of an aortic aneurysm?
In the infrarenal position,
any aortic diameter greater than 3 cm.
You might be a little surprised,
3 cm is not that large,
and yet that aorta is
responsible to be a conduit
for supplying blood all over your body.
This is considered a progressive dilation.
Didn't happen overnight.
And by the time it either
or something that we’ve picked up,
it's probably been many years in the making.
Here in the diagram,
you notice an aneurysmic sac.
When you look at it compared to
the normal anatomy to the left side,
it’s clearly an aneurysm
or a bulbous bulging
of the vascular wall.
As I previously described,
we think of abdominal aortic
aneurysms as multifactorial.
There’s likely a genetic component
because it does seem to run in some families.
And there are pro-inflammatory mediators,
hyperlipidemia, atherosclerotic plaques.
And there are also biomechanical
stressors on the arterial wall.
These factors are particularly
exacerbated by high blood pressure.