Now we already completed discussion of atrial
fibrillation. Stop, take a breath, moving onto
flutter. Okay. So the end part of this
section for supraventricular tachycardia will
end with flutter as being our discussion.
Atrial flutter is a regular atrial tachy.
Read regular. What happened to atrial fibrillation?
Irregular. Next. Atrial discharge, extremely
quick but you know what, we also found that
with atrial fibrillation, but interestingly
enough you want to take a look at the following.
300 beats per minute shall
we say, then 2:1 fashion in terms of its ratio.
What does that mean? A 2:1 to P waves to every
QRS complex, leading to a regular tachy at
approximately 100 beats per minute. So for
every QRS complex that you get, you
might have two P waves giving you a total
of how many? 250 to 300 beats per minute as far
as atrial conduction, but then in terms of
its regular tachy, it will approximately 150.
Makes sense of that? That is your simple math.
Now the "F-waves" on ECG will then give you
your sawtooth. Let me take a look at this
ECG. Sawtooth type of appearance, regular
rhythm, the QRS complex is showing up regularly
and it is a fact that it is a 2:1 ratio. So
look for that and you will be in good shape
for flutter. Well take a look at some etiology and
such coming up shortly. Patient can be
asymptomatic present with palpitations, lightheadedness,
now syncope all these are nonspecific all because
of decreased cardiac output as you can imagine.
Palpitations, increase heart rate, lightheadedness,
and syncope. Causes. Now I'm going to slow down here just a little bit.
Make sure that we are clear. The causes
that we saw for atrial fibrillation were very
common things such as hypertension, diabetes
mellitus, pulmonary embolus, so on and so forth.
Here with atrial flutter, a little bit different.
Post-bypass, huge. We have PE in both, atrial
fibrillation, atrial flutter. Irregular, what
does that mean to you? Afib. Regular, you're thinking
about atrial flutter. Valvular heart disease,
CHF and perhaps even digitalis or digoxin
toxicity. Causes of atrial flutter.
You really want
to pay attention to that ECG. Sawtooth is what
we saw and we'll talk about rate control. Once
again here is my dig, why? Not because of its
effect on inhibition of sodium-potassium
pump per se, it is the fact that it is able
to slow down the AV node. Which calcium-channel
blocker works better on the heart? The verapamil,
V verapamil, V ventricles okay. Where does it
favours your dihydropyridine such as nifedipine works
much more on your blood vessels. Clear? Metoprolol,
what is that? A Beta-blocker. What are we
trying to do? Control our rate. If there
is no spontaneous cardioversion after medical
therapy, then electrical cardioversion can
be performed. So keep that in mind as far
as the next step of management. Medically speaking
you are cardioverted by using medicine, maybe
dig, maybe a beta-blocker. But if that did
not work, then you have to resolve to electrical
cardioversion, if greater than 48 hours, 3 to 4 weeks
of anticoagulation. Now, what are you seeing here?
Take a look
at the bottom strip and you find that you
have atrial flutter here. Keep in mind if
you want to compare this to atrial fibrillation,
please. This is going to be a 2:1 type of flutter,
which means that you will have an atrial conduction
of approximately 200 to 300 beats per minute, with
the QRS complex of 150. 2:1. Now,
what are you seeing there is the fact that
the atrial flutter was a sawtooth type of appearance.