Well welcome to another MedCram video here. We've got our next EKG
Which we're going to talk about we're going to go through this in a methodical fashion using our tried-and-true
technique of
Rate Rhythm Axis Hypertrophy and then looking for ST
Segments, so first up is figuring out rate, and we can see here
We've got the QRS
complex
And a QRS
Complex here what we're doing is we're looking at how many boxes are between it, and it's a little bit more than one
but less than two, in fact
it's a little bit less than one and a half so if we take
300 and divide it by less than one and a half we're gonna be in the approximately the one
sixties to one seventies
the other way to look at it is to look at the number of qrs complexes so 1 2 3 4 5 6 7 8
24 25 26 27 and 28 and multiply it by 6. So if we go
28
times 6 is gonna give us a total of about
168
beats per minute so that's where we come up with the number of beats per minute remember, this is a
10-second strip and so if we multiply it by 6 we'll see how many times you'll have it in one minute. So that's rate
let's look at Rhythm next and
For rhythm, We're going to look at each of these QRS complexes and see if there's p waves see if they're regular Etc
etc. One of the things I think that's interesting what we'll do here is zoom up...
You can see here very clearly that there's a little p wave after each QRS complex
Which is kind of interesting right? You can also see a little notching right there after each
QRS complex, and what's going on here? This is very fast
So you have tachycardia as we've already said
But it's also very regular and there's p waves after the QRS complex this type of a pattern you'll see in
AV Nodal re-entrant tachycardia
So I think that's what's going on here with the rhythm
So here we have the rate of 168 we have a rhythm of AV nodal reentrant tachycardia
The next thing is to go on to axis
So the thing again to remember on axis if we draw a nice circle
remember that the line going out this way is lead 1 and
the line going down this way is
AVF so
If we look at lead 1 we can see here that it's very positive, obviously these are positive
QRS complexes and so we're gonna be in
This direction over on the right-hand side of the screen
but on the left-hand side of the patient and then in terms of AVF we can see clearly here that we're dealing with a
slightly negative
QRS complex and so therefore, we're going to be going opposite so kind of in this direction
And so it looks as though that the vector that we're going to be talking about is slightly negative
And it's a as in fact as it turns out the computer
measures it out at negative 8 so negative 8
Degrees is going this direction is very close to almost being right on to AVL
Okay, and you can see here that AVL is probably one of the most positive
leads
Similarly ninety degrees to AVL is this one right down here? Which is lead II and so because we know that
The the Vector is going almost
Parallel to AVL that any lead perpendicular to the vector is going to look isoelectronic
So let's see if it is isoelectronic and lead II and sure enough
We go to Lead II and you can see here that for the most part what we're dealing with here is
isoelectronic
so that makes sense that our
Ventricular axis is going to be slightly left. Maybe a little bit of left ventricular hypertrophy there at
Negative 8..
The axis is negative 8 degrees. Let's move on to hypertrophy and ST Segment changes
So we're gonna zoom up and look at those precordial leads. We can't really see if there's any
atrial hypertrophy because of the AV nodal reentrant tachycardia in nature, but if we look at V1
We're looking for right ventricular hypertrophy and specifically is the R wave
Bigger than the S wave and in this case, it's certainly not so there's no evidence for right ventricular hypertrophy
But then and looking for left ventricular hypertrophy what we're doing there is we're counting up the size of
the S wave which in this case is 10 11 12 millimeters and
Now we're counting up and looking at the R wave in lead
V5 and the R wave in lead V5 looks like it's five six seven
millimeters and
we can see here that twelve plus seven is total of
19 and
19 millimeters does not meet the criteria for
35 millimeters, and so therefore there is no evidence of right ventricular or left ventricular hypertrophy
Okay, what about ST Segment Depression?
Well, we can see here that there is some ST Segment Depression in Lead V1
It seems to be more pronounced in II in
III and also in AVF not to mention in V5
V4
Also then in V6 there's some up-sloping here in V3
Though The J point
is not exactly clear, seems to be less in the V1 and V2 area but certainly in the inferior and
Also in the lateral leads, we're starting to see some ST
Segment depression it could be because of ischemia from tachycardia from the AV nodal reentrant tachycardia
But definitely seeing some ST Segment depressions there
So to summarize no hypertrophy seen, but there is some ST
segment depression in II, III, and AVF and also in V5 and some of those lateral leads
So we've gone through it pretty systematically, and we found this AV nodal reentrant tachycardia with a heart rate in the 160s
with a left ventricular
Axis deviation no hypertrophy and ST Segment depression in the inferior leads and
Thanks for joining us