00:01
Hi, welcome to our video series
on the electrocardiogram.
00:05
In this one, we're going to talk
about something pretty dramatic.
00:08
We're talking about the treatment
of ventricular tachycardia.
00:12
Now there's your old friend, normal sinus rhythm.
00:16
We're going to review why this is not
normal sinus rhythm, And it's V tach
Heart rate is fast, the rhythm is
regular, but it's only ventricular.
00:28
We can't see a P wave, so we
can't measure the PR interval,
and the QRS is pretty weird
looking and it's greater than 0.12.
00:39
Now we've got that graphic for you again
So you see where it's all happening
where all the activity is
going down is the ventricles.
00:46
Because ventricular tachycardia occurs when the
electrical signals within the lower chambers
that we call the ventricles, all happen in
there and it causes the heart to be too quickly.
00:58
Now this is an emergency.
01:04
You will see people go flying into a
patient's room if they see this dysrhythmia
because you need urgent medical treatment
for your patient if they're in V tach,
because V tach can lead to sudden cardiac death.
01:19
So the goal of treatment of V Tach is to
restore a normal heart rate and function
so we can perfuse the patient's body.
01:28
Okay, defibrillation and cardioversion.
01:30
This is where it gets pretty exciting.
01:32
Unless you're the patient, then
it's not quite as interesting
but for those of us to be ready to help a
patient in V tach, here's what you need to know.
01:42
See, the acute treatment somehow involves
delivering a jolt of electricity.
01:47
There's a couple ways we deliver that
either in defibrillation or cardioversion.
01:52
So, if a patient is acutely
experiencing ventricular tachycardia,
we're going to actually deliver a
jolt of electricity to the heart.
02:01
Now, we can use this with a defibrillator,
or with a treatment called cardioversion.
02:06
And we usually typically use that with
patients with a pulse, who are unstable.
02:11
So on the left, you see the patient with
defibrillator pads and see how those are aimed
So the electrical jolt can
go right through the heart.
02:21
Now you'll see wires that go off the screen there.
02:24
That's because that is hooked
up to a defibrillator machine.
02:28
We used to have to place the paddles
long ago on a patient's chest,
but that makes the health care
provider have contact with the patient.
02:37
So it is safer for everyone if you put
the sticky patches on in the correct spot,
and then you just push a button
to defibrillate the patient.
02:47
Now, I'm going to break this
down a little bit more for you,
but we have some treatment called
Advanced Cardiac Life Support.
02:55
Now that is a whole course so we're
not going to break that down for you,
because that's not what we're doing here.
03:01
We just want you to have an overview
of ways that we could treat V tach.
03:07
Alright, here's one of my favorite study tips.
03:10
When you're trying to learn about two
concepts, it's important that you know
the similarities and the differences.
03:17
So line them up right next to
each other and compare them.
03:20
For example, I'm going to show you on
defibrillation versus cardioversion.
03:25
On the left, we have defibrillation, think
of this as a boom, this is a really big tool.
03:33
It's not synchronized to the heart rhythm, and
we use it for patients who are in cardiac arrest
meaning pulseless V Tach which we're
talking about here, or even V fib.
03:43
Now defibrillation is with
some pretty high energy joules.
03:48
We're not giving you the exact numbers
here, because you'll learn that
in Advanced Cardiac Life Support.
03:53
This is just an overview for you.
03:56
So defibrillation, it's big
and it's not synchronized.
04:00
We use it for serious rhythms
like pulseless V tach, or V fib,
and we're gonna use a pretty big jolt.
04:07
Cardioversion, on the other
hand, it's a little more elegant.
04:12
It's synchronized on the patient's R wave.
04:16
It's only used with patients
who are unstable hemodynamically
and still have a pulse, but they're showing
us that this is not going well for them.
04:25
They can't keep their blood pressure up.
04:26
They're having chest pain, any signs that
show us they are not hemodynamically stable,
makes them a candidate for
us to consider cardioversion.
04:36
Now defibrillation, Boom! Those are the big joules.
04:40
Cardioversion is a lower energy.
04:43
Think of it more as a dance.
04:45
So cardioversion is synchronized,
defibrillation - not synchronized.
04:50
We use it for pulseless V tach or V fib.
04:54
For cardioversion, we use unstable
patients who have a pulse.
04:59
They still have the V tach but they have a pulse.
05:03
High joules for defibrillation, lower
energy joules for cardioversion.
05:08
Now that you have kind of the
basic foundation of the difference
between defibrillation and cardioversion,
let's dive a little deeper.
05:15
So defibrillation is best when the cardiac cells
are not anoxic, and the patient is not acidotic.
05:23
Now let's talk about what those are.
05:25
Anoxic means "without oxygen."
So if the cardiac cells specifically have been
without oxygen for a very long period of time,
we're going to have poor results.
05:36
Acidotic refers to the pH of your
blood, normal is 7.35 to 7.45.
05:44
Someone who is acidotic will be lower than 7.35
See, anoxic cells means oxygen, they've been
deprived of it for a significant period of time,
And acidotic is another indication that
woah, things have gone really downhill.
06:02
These patients are not the ones who
most benefit from defibrillation.
06:08
Now it's best to perform the defibrillation
within 15 to 20 seconds of the arrhythmia onset.
06:14
This is the best method to terminate V tach.
06:18
Have you ever wondered why you go to the
gym or when you go to a school ballgame
that there are those
defibrillators around on the wall?
That's because if you're going to save someone
from V tach, whether they're a young athlete,
or up to an elderly person who's watching the
game, you have to perform the defibrillation
as quick as possible to try to save their life.
06:41
Now a defibrillator, is that passes
that direct current through the heart,
so it depolarizes the cells.
06:48
Now there's a period of repolarization that may
allow the SA node to resume as the pacemaker.
06:55
So that's a very long way of saying when we put
this large electrical charge through the heart,
what happens is it depolarizes the
cells and then when things repolarize,
that may kick the SA node in, it's a
pretty dramatic reset of someone's heart
and if it works, it's brilliant
and it is amazing to see.
07:20
Now cardioversion can sometimes
be similar to defibrillation,
but remember, it's much more dramatic,
but in cardioversion the shock is programmed
to be delivered during the QRS complex
so it's that more synchronized version.
07:36
Ventricular tachycardia ablation is a
procedure to eliminate the areas of the heart
where there are erratic electrical signals arise
that are causing the heart to beat ineffectively.
07:47
The procedure starts with the insertion of a
catheter sheath into the patient's femoral vein.
07:53
This will be used as a guide to
insert a catheter into the sheath
to guide it through the venous system
until it reaches the patient's heart.
08:03
In the heart, the doctor will guide the catheter
to the area that is causing the arrhythmia.
08:09
The tip of the catheter either
emits a hot or cold energy
that will allow the physician
to ablate the tissue.
08:17
This ablation causes this area to
stop firing those erratic signals
and therefore stops the arrhythmia
An epicardial needle is used to
gain access to the epicardial space
between the epicardial membrane surrounding
the heart and the outside surface of the heart.
08:35
The ablation catheter is
placed in the epicardial space.
08:39
The outside surface of the heart is mapped
- coronary arteries and the phrenic nerves -
before the ablation is completed
in order to avoid injury.
08:50
The implantable cardioverter
defibrillator is also called an ICD.
08:55
The ICD will detect a rapid
heartbeat coming from the ventricles
and deliver a shock to reset the heart.
09:03
Now, this is what my mom had placed and
also with a pacemaker portion of it.
09:08
This is a pretty incredible device, because
you know that we need to get the shock
there within 15 to 20 seconds if we know
a patient is at risk for this dysrhythmia
and we put the cardiodefibrillator
right in their chest wall,
they have a much better chance of survival.
09:27
So let's wrap up this portion of our video series.
09:30
Sustained V tach is a life threatening
emergency that can be treated
acutely with cardioversion
if the patient has a pulse,
or defibrillation if the
patient does not have a pulse.
09:42
Ventricular ablation and implantable
cardiac defibrillators (ICD)
are the options for long term treatment
of recurring ventricular tachycardia.
09:52
Thank you for watching this
part of our video series.