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NHLBI Orloff Award 2018: Jaffar Kahn

[Dr. Khan] On the 1st of
May, we got a phone call. They were implanting
valves in their patients, and the patients’ own leaflets
got in the way of blood flow. All of us got together and sketched out a plan of how to do this. And on the 25th of May, we were ready to do our first patient. I’m Dr. Jaffar Khan, I’m a
Staff Clinician at the NHLBI. We’ve developed two procedures called LAMPOON and BASILICA. And what they do is,
they cut the patient’s own valve leaflets, making room
for these implanted valves. This is a patient with
a failing Mitral valve. Referred for Transcatheter
Mitral Valve Replacement. Over 50% of such patients who need Transcatheter Mitral Valve Replacement don’t get it because of the risk of left ventricular
outflow tract obstruction. This shows you that the
actual pathophysiology of the problem is that anterior leaflet. No blood can flow through there. The initial thought was to use balloons, and we thought they’re
probably a bit dangerous. So, we dusted off our
old electrosurgery unit, picked out wires and
catheters from the shelf, and just played around with it to see how we could concentrate electricity on where we want it to be. We had bench top models
with pieces of meat that we were electrifying to
see how it would cut through. These wires are inside blood,
which conducts electricity. So, electricity would go everywhere. We needed to really focus it, so we made kinks in the wire, we scraped little pieces of the wire, we insulated it with small sheathes, we injected dextrose
through the whole field, which is not ionic, so it doesn’t conduct. We used tools that were readily available, and used them to focus electricity on the heart valve that we wanted to cut. Surgeons do this when they replace valves. They cut open the heart, they see the leaflet, and cut it out. What we want to do is offer this to patients who can’t undergo that. Who are too frail, perhaps. Or don’t want to undergo
such an invasive procedure. We wanted to offer them a
minimally invasive procedure. The LAMPOON procedure is
entirely transcatheter. It uses two catheters
which are inserted through two millimeter incisions in the groin, which are positioned either side of the anterior mitral leaflet, which we wanna cut. One side has a snare, and
a guidewire is electrified and burns through the base
of that anterior leaflet, and is snared on the other
side of that leaflet. So, now you have a
guidewire across the leaflet that you wanna cut,
surrounded by catheters. Those catheters insulate the wire and it’s electrified
further with the operator having both ends of the
guidewire outside the body. As he pulls that wire, the leaflet splits straight down the center. And now, this valve is ready for transcatheter mitral
valve implantation. Here it is, the transcatheter mitral valve is implanted in position on
the left without LAMPOON. And, on the right with LAMPOON. If you look down the barrel of the left ventricular outflow tract. You can see this is completely obstructed, and this patient would not survive. With LAMPOON, that leaflet
is parted out of the way, and blood can flow through,
enabling this procedure. We use similar techniques, but BASILICA would do that for the aortic valve, for transcatheter aortic
valve replacement. And that prevents coronary
artery obstruction, which is the blood supply to the heart. As far as we know, this is the first endovascular technique to
cut heart valve tissue. LAMPOON has been performed
in over 50 patients, and BASILICA in close to 40 patients, across North America and Europe. For the majority of patients
who have heart valve disease, the majority of those patients don’t have that option of having open heart surgery. So, this is really a
lifesaving treatment for them. (uplifting music)

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