Melanie (Host): Welcome to UAB MedCast.
I'm Melanie Cole, and today we're speaking about current
management of atrial fibrillation.
Joining me is Dr.
William Maddox.
He's an associate professor of medicine in the division of
cardiovascular medicine in the section of electrophysiology at UAB Medicine.
Dr.
Maddox, thank you so much for joining us.
when you look at AFib, the landscape today compared to even five years ago.
What stands out to you as the biggest shift in how we diagnose, stratify,
and even manage these patient's?
You and I did a previous podcast on this topic.
Why are we updating it?
What's exciting?
William Maddox, MD: Thank you for having me, Melanie.
it's always great to come here and be able to talk a little bit about some of
the interesting things that we do at UAB.
the management of atrial fibrillation has really changed dramatically
in the last several years.
atrial fibrillation is the most common sustained arrhythmia that we see.
And as our population ages we're, just seeing more of it.
I had 40 people in clinic yesterday and 29 of them had atrial fibrillation So,
It is certainly a common disease process that we're managing on a daily basis.
The most exciting thing that we've seen in the last several years is
that our treatment for symptomatic.
Drug refractory atrial fibrillation.
the mainstay of treatment has always been either cryoablation or
radiofrequency ablation, which are two different treatment modalities
for, delivering energy and isolating the pulmonary veins and other,
arrhythmogenic areas in the atria.
And what has now forefront is ablation.
Efficacy with some hopefully increases in safety.
And as we're finding some novel areas that we can treat that we weren't as successful
with or couldn't treat because of risks to contiguous structures such as the phrenic
nerve or the lungs or the esophagus.
Melanie (Host): Well, thank you for that.
So, I mean, it is an exciting time in your field, Dr.
Maddox.
So let's talk about.
Pulse field ablation, it's now becoming a mainstay of treatment for energy delivery.
So speak a little bit about that.
How is that broke onto the scene?
What's it doing for you?
William Maddox, MD: Sure.
Pulse field ablation This is electroporation of the cells of the
myocardium, and This is actually a treatment modality that has
been used for years for to deliver chemotherapeutic agents and other.
Medications to specific cells within the body.
And it had been used in the treatment of, solid tumors and other things.
And what it does is it, it passes a electrical impulse through the cell And
then permeates the cell membrane to allow traditionally the cell membrane to be more
receptive to intake of chemotherapeutic agents and other biologic agents.
Traditionally it had been used for this delivery of drugs and it was something
that we tried to have reversible damage to the cell, such as the cell would
become more permeable for a period of time And then would repair itself
And that permeability would close.
Pulse field ablation in when we're using it for ablation is we're looking
for permanent, irreversible, Damage to those cells such that the cells undergo
program cell death And that we create a line of scar so that the electricity
can't pass from pulmonary veins or other arrhythmogenic tissue And that the
arrhythmia can continue to propagate.
One of the challenges that the industry and, And the field in general
has had was creating wave forms.
Of electrical energy that would pass through these cells that would be
successful in, permeating the cells And then causing irreversible cell death, but
didn't damage any contiguous structures.
And, and That is, a topic for another time, and I'm not an expert there, there
are some really smart engineers who have spent years And in their entire
career helping to develop these things.
we've learned more about it and, way that the electricity is delivered to
those cells can be very selective to the cardiac tissue that allows us to target
the myocardium, but hopefully spare the energy delivery to things like the
esophagus, the lungs, the phrenic nerve.
Melanie (Host): So Dr.
Maddox, then, what are you seeing in terms of durability, reconnection rates,
long-term freedom from arrhythmia?
It's been described as kind of a workflow changer, particularly
regarding tissue selectivity safety.
How is it altered for you?
Procedure times recovery.
All of those things.
William Maddox, MD: Anytime that we introduce a new treatment modality to,
any of our arrhythmias that we treat, what we're looking for is, First that we're
just as effective as we were with our prior modality or our predicate modality.
Hopefully that we are safer, And also that, if we can be, that we're more
efficient And this world of more and more patient's that need to be treated.
Increases in efficiency in the lab means that we can treat more patient's
and hopefully help more people and get them home in a timely fashion and back
to the lives that they wanna lead.
there are multiple companies that create these catheters and there's been several
different that are, now FDA approved.
And so with each iteration of, of what comes out, we've become.
Better and more efficient at it.
Honestly, now, most commonly, we are using catheters that allow us to
deliver both pulse field energy and radiofrequency energy, And we can be
selective about where we do either one.
Our efficacy has been equivalent to what we see with radiofrequency
ablation or cryoablation.
We're still seeing.
in our lab first pass isolation, which means that as we go around the
pulmonary veins on the left side of the right side with one pass around the
vein, we get isolation of that tissue.
We're seeing that about 95 to 97% of the time, which is equivalent,
or even sometimes a little bit better than what we saw with rf.
the procedural times are shorter.
these catheters are delivering larger lesions than what we see with our smaller
footprint, radiofrequency catheters.
the time has come down about 15 or 20%, and certainly one of the most exciting
things for us is that there are some very.
Rare but, devastating complications that can occur when we're
bleeding in the left atrium.
one of the most significant of which is atrial esophageal fistula.
This is a, devastating complication that if it occurs is many times fatal and with.
Thousand of these.
Now done in all of our preclinical research, we have not seen any damage to
the esophagus with pulse field ablation.
That is probably because we are both.
The wave forms that we use are cardioselective, which means that they
are damaging the myocardial tissue, but not the smooth muscle tissue,
the esophagus, but also the, field strength of the, energy falls off
fairly rapidly, such that, Tissues that are farther away from where we're
treating aren't seeing any increases in heat or any damage to the cells.
So, it's an exciting time for us.
Melanie (Host): It certainly is.
Are there specific patient groups, Dr.
Maddox, persistent, as you said, refractory af, older adults, structural
heart disease, where this has more benefit, especially pronounced.
What factors influence your choice when you're counseling your patient's and
thinking about shared decision-making?
William Maddox, MD: There's been a lot of information in the media about
pulse field ablation, and many of my patient's are very well informed when
they come to me so many times they're bringing it up as well and asking if we.
Have the new technology and, they'll say, PFA is, what is most commonly
kind of the vernacular that they use.
The pulse field ablation is really our first-line treatment for patient's
that have either paroxysmal or persistent atrial fibrillation,
that, This is the first-time that they're having catheter ablation.
There are some considerations for.
Areas that can be challenging With pulse vote ablation, if the patient has, a
mitral valve That is, metal, so it's a prosthetic, mitral valve, or if they
have other large structures that are metallic in the heart, there is some
data That could be a, an energy sink from the electricity and, And we may
have inconsistent delivery of energy to the tissue that we'd like to treat.
So if someone has a watchman or an EM plaster device or something like
that, that, I'm worried that the energy might be pulled into that
metal rather than, go to the tissue.
Like I expect.
I'm usually using RF in those patient's.
Also with the catheters that we have that allow us to both use RF and NPFA.
There is some, data that, sometimes the PFA may cause
spasm of the coronary artery.
So if we're treating very close to the coronary arteries, I'll simply
switch to radiofrequency with that catheter for several lesions
while I'm close to the coronary artery And then switch back to PFA.
Once I feel like it's safe, we're able to, see the.
Coronary arteries in real-time using intracardiac ultrasound.
So that has not been a problem, and I haven't personally seen any
coronary artery spasm, but that's mostly because I think we're pretty
judicious about where we deliver energy.
Melanie (Host): Well, it certainly is such an exciting time and an interesting time.
Now when we think of AFib, Dr.
Maddox, besides PFA And the treatment modalities, monitoring
is a thing And in this world, as you say, of technology wearables.
What are you seeing changing, monitoring, keeping track, helping
your patient's keep track or electronic monitoring for the medical staff.
William Maddox, MD: Absolutely.
That's a great question.
So for years we've had loop recorders that, can be placed on the,
anterior chest wall or multi lead.
Uh.
Holter monitors that the patient can go home with that allow us to record
their EKG for up to 30 days typically.
But now with the advent of these wearables such as the Apple Watch and
multiple manufacturers now have, the ability to have real-time EKG recording.
Many patient's are coming to me and their first diagnosis of
atrial arrhythmia comes from their.
Wearable itself, these are quite easy.
And with a watch on one hand and simply a finger from the other arm touching
one of some electrode that the wearable has, you're able to reliably record
lead one of an EKG fairly easily.
and these, I found, have been quite useful for patient's both in initial diagnosis
of atrial fibrillation, but also for.
Monitoring of recurrence after either medical therapy or catheter ablation.
Melanie (Host): Dr.
Maddox, as we wrap up, what would you like other providers to take
away from the current management of atrial fibrillation And what
you're doing there at UAB Medicine?
That's so exciting.
William Maddox, MD: With more and more patient's having atrial fibrillation,
I want our providers out there to, to to really have a thought.
Getting these patient's to us early in their disease process is our best chance
of being able to intervene and, make them symptom free for the long-term.
So if you see somebody with atrial fibrillation sending them
to us to, take a look and see if medical therapy with either.
Rate controlling agents, anti-arrhythmic agents is best, or if proceeding
with something like catheter ablation is in their best interest.
These are day procedures.
The patient comes in, it typically takes me about an hour procedure,
time to do, sometimes a little less, and after a couple of hours of bed
rest, the patient is able to go home.
The complication rates are very low.
I quote people little less than a 1% chance of complication
and success rates are high.
Patient's in general are very happy with their arrhythmia control after an
ablation, And the earlier we can see these patient's before atrial myopathy
and, fibrosis occurs, the higher the likelihood that we can be successful.
Melanie (Host): Great information.
Thank you so much Dr.
Maddox, for joining us today And for more information, please visit our
website at uabmedicine.org/physician
dot org slash physician.
That concludes this episode of UAB MedCast.
I'm Melanie Cole.