See One, Score One for Stents When
the task at hand is performing angioplasty and placing a stent,
the phrase being used more and more is "lesion-specific strategy".
What does this mean? Well, looking at the angiogram on the left,
you can certainly see the lesion, or blockage...or rather, you
can see where the narrowing caused by the blockage is. You can't
actually "see" the lesion itself unless, of course, you
could get inside the artery with a camera.
That's
basically what intravascular imaging does: a device is threaded through
the arterial system, along a guide wire (the same wire that the balloon
and/or stent will track) and, using ultrasound or lasers or near-infrared
energy, it will image the inside of the artery. The most commonly-used
system is called IVUS (IntraVascular UltraSound).
An angiogram doesn't show the cardiologist much
about the shape, distribution, or composition of the atherosclerotic
plaque: it mainly shows where it is and approximately how long it
is. But, seeing inside the artery, the cardiologist is able to discern,
for example in the image above, that the plaque is eccentric, all
on one side, or perhaps it's ragged or sitting next to calcified
deposits. Putting a balloon in and expanding it may push the calcified
plaque through the arterial wall, causing a dissection, or the eccentric
nature of the lesion may impede the balloon from fully expanding,
leaving a less-than-optimal result.
Back in the early days of angioplasty, I watched
cardiologists as they saw post-balloon angioplasty images from a
very early intravascular device: the angioscope -- literally a camera
on a catheter. These were among the first cardiologists to ever expand
a balloon inside a human coronary artery...and they were shocked.
I remember Dr. Richard Myler exclaiming, "My God, it looks like
a bomb went off in there!"
Indeed, it looked pretty raggedy -- the balloon
dilated the artery alright, but the plaque split up during the balloon
expansion in a very messy fashion: there was fatty plaque hanging
off the sides of the vessel wall and the whole picture showed something
definitely not smooth. This was one reason that plain old balloon
angioplasty (POBA) had a 30-40% restenosis rate.
When stents were invented, cardiologists now had
a cage, a scaffold, to push this tissue back against the vessel wall
and pin it there. But still, if the plaque were hard, uneven, etc.
the stent would not sit quite perfectly, and restensosis or even
thrombosis (blood clots) might occur.
Enter lesion-specific strategy -- you look at the
plaque characteristics and pick the right tool for the job. You have
to have an intravascular imaging system to "see one" --
that would be IVUS -- and then, if you saw that the plaque was complex
or atypical, you'd need a tool to safely break it up -- and that
(in some cases) would be the AngioSculpt® Balloon Catheter.
As you can see in the animation below, the nitinol "ribs" on
the balloon act as a scoring device. We all know you can't break
a piece of glass along a line, but if you score it part-way first
with a glass cutter, you can break it perfectly straight. And so,
if the IVUS image shows an irregular complex lesion, what's known
as a type-C, you might want to pre-treat the plaque, so that when
you do expand the stent inside, the plaque expands easily, atraumatically,
and smoothly -- seating the stent cozily, right up against the vessel
wall.
That's the basic concept of the AngioSculpt
balloon, manufactured by AngioScore, Inc. And today Volcano Corporation
(Nasdaq: VOLC), makers of IVUS equipment, announced that
they are now the distributors for Japan of the AngioSculpt line.
It's a perfect fit because it marries distribution of the technology
that allows you to "see one" with the technology that allows
you to "score one" -- making outcomes for patients better.
Heart Attack and Angioplasty: A Public
Education Challenge This
week's JAMA contains an
important study about the relationship of financial concerns
to delay in seeking treatment for heart attack. No surprise:
people with no insurance tend to delay going to the ER when they
are experiencing symptoms of a heart attack. Conversely those
with full insurance are more likely to go within two hours.
But what's most important to me about the study
is that while the fully-insured patients were more likely to
seek out timely treatment, almost 40% of them delayed going to
the hospital for more than six hours -- leaving them with a
legacy of damaged heart muscle and future heart failure -- needlessly!
Obviously, it's not just money keeping heart attack
victims away from the ER. Do you know someone who's had the symptoms
of an MI and has tried to make-believe they're experiencing something
else: a pulled muscle? an acid stomach? To be trite: denial -- not
just a river in Egypt. You get the idea....
Of course, many times the onset of a heart attack
does not present as the classic crushing chest syndrome, where you
grip the heart and say, a la Redd Foxx, "Call 911! I'm havin'
the Big One!" Sometimes the symptoms are subtle, like my relative
who was sitting on our couch after dinner one night, complaining
of indigestion. It wasn't. It was a heart attack.
Unluckily for him, it was 1972. It would be five
years before the first
angioplasty would be done and another three before Geoffrey Hartzler decided
to open up his patient's artery with a balloon in the midst of
an acute infarction, miraculously stopping the heart attack in its
tracks!
I wrote
recently about the evolution in the treatment of heart attack
since the days of Eisenhower. I remember those days, as a kid in
upstate New York, walking home from school on a sunny weekday afternoon
and seeing at least four of my friends' fathers, sitting on their
front porches in their rocking chairs. I always wondered why these
fathers didn't go to work during the day like mine did. Heart disease
was why. Four fathers, just on my one block, had been struck down
by a heart attack. They could no longer work, could barely drive
a car and they all died in their 50's.
So perhaps this is what we all visualize when we
think "heart attack" -- it's an upheaval, a catastrophic
end to a life of work and play, sitting on the front porch and waiting....
Perhaps this is why people who suspect they may
be having a heart attack don't want to go to the hospital -- it's
not going to make a difference -- I'm done for already.
Except that's not the case at all today. As angioplasty
pioneer Dr. William O'Neill relates in the video clip below, angioplasty
has radically changed all of this and has "taken the dread factor
out of heart attacks." In our interview, he actually characterized
the experience of having a heart attack treated today as "not
so bad, perhaps a little more than a cold."
An over (or under?) statement to be sure, but maybe,
if more people understood this, there would not be so many staying
away from the ER. The ACC has done a great job with its "door-to-balloon" initiative.
But that's what occurs inside the hospital doors. What needs
to happen now is some significant public education to get those patients
knocking on the door outside for help!!
"I'm a Dead Man" That's what patient R.B. said to his
family when he was told by two different surgeons that his
abdominal aortic aneurysm could not be repaired. It was large
-- more than 7cm -- and in danger of rupturing -- fatal four
out of five times. Such aneurysms had been repaired surgically
for almost half-a-century, but not for this patient. He had
COPD, chronic obstructive pulmonary disease, and he would not
survive a major traumatic surgical procedure that involved
opening his chest and putting him under general anesthesia.
As he told me during a 2001 interview for my documentary, "Vascular
Pioneers":
You can't put the feeling that one gets
on tape or on paper or anything else when one is told, "You're
not a candidate. You're dead." There's nothing that can
describe that feeling. I wept. I cried. I could do it again
right now.
But what his surgeons
didn't know in the year 2000 (cue Conan) was that only a few
miles away a new type of aneurysm repair was being done, using
a stent graft, delivered like angioplasty via catheter through
the femoral artery -- no general anesthesia, no opening of the
chest cavity. Maybe his surgeons didn't know about it -- but
there was this thing called the Internet -- and using this tool,
our patient's
Dr. Takao
Ohki
good friend found Dr. Takao Ohki, then at Montefiore
Hospital in New York City, where the first endovascular AAA repairs
were done. Within a few weeks, he visited with Dr. Ohki who determined
that R.B. was in fact a candidate for this minimally invasive procedure.
He did it, it was successful. And here a year later the patient was
talking to me on camera.
So the anecdotal experience of feeling the emotions
of this patient very much informs my interpretation of the two
studies published today in the New England Journal of Medicine.
There are charts and graphs and tables, and 30-day outcomes and five-year
outcomes...but I remember the man who would not be sitting in from
of me were it not for this ingenious metal cage covered in fabric.
Angiogram Not Angioplasty For Holbrooke A
minor print error, but not for Richard Holbrooke, the U.S. special
envoy for Afghanistan and Pakistan. On Wednesday BusinessWeek,
among a number of other news outlets, reported that Holbrooke would
have to forego an important trip to Afghanistan in order to undergo
a procedure to open his "clogged heart valves". They
called it an angioplasty.
In fact, the procedure was an angiogram.
Two letters and 10-20 minutes shorter -- but a world of difference.
Having reports of chest pains, Holbrooke's doctor ordered a diagnostic
test, also known as a cardiac
catheterization: a catheter is threaded through the femoral (groin)
artery or the radial (wrist) artery to the coronary arteries surrounding
the heart. A special dye is injected and, under X-ray fluoroscopy,
any blockages can be seen. In Holbrooke's case, no significant narrowings
were found and he has, in fact, been cleared for his trip.
Had a major blockage been found, an angioplasty might
have been done: guide wires rapidly would have been exchanged and
a balloon with a stent on it would have been threaded to the blockage,
inflated for a short time, deflated and withdrawn. The stent would
remain as a scaffold, holding the artery open. Only 20 extra minutes,
maybe 10. This is why many angiograms that show blockages are converted
into therapeutic procedures, angioplasties, right on the table --
because it's easy and fast to add it on. ("And while we're at
it, we'll change the oil...", a cardiologist friend of mine
used to quip.)
Of course, this instant conversion, also called "ad
hoc angioplasty", has come under some questioning since recent
studies, notably FAME,
have shown that just because you can see the blockage doesn't mean
you need to open the blockage up. But that's another story.
This story ended well for Ambassador Holbrooke.
And by the way BusinessWeek -- clogged heart valves?