Interactive Transcript
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When there is ECG synchronization, there can be
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problems with the synchronization either because
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patients has arrhythmia, ectopic beats, or the scanner
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fails to recognize the, um, uh, certain portions
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of the cardiac cycle, notably the, uh, R wave.
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So these are pretty common and sometimes they lead
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to dramatic action like getting the patient back.
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Often all they need is just a little bit of editing.
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So here's an example of a patient who
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came in for a pre-op evaluation for a
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TAVR, the endovascular aortic valve.
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And in that we get multi-phase
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images of the aortic root and aorta.
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And you can see here quite clearly that there
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is a lot of artifacts, motion artifacts.
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And the thing to do then is to go to the scanner and
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look at the raw data and look at the original ECG.
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The original ECG you can get by looking at these tabs.
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Of course, it depends on which type of scanner you have.
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And you can get something like this,
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a rhythm strip, a single rhythm strip.
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And you can see here what the problem is.
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We've got a nice little block here,
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a nice little block over here, a nice
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little block over here, a nice block here.
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And then in between we've got PVC.
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That's confused.
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The, um,
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scanner, and there is a compensatory pause.
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That's the reason why you have
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that motion out of bounds.
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And in order to deal with this,
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you have to really set yourself.
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Okay, what should the patients
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rhythm have been, had they not been
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that PVC and then insert a new kind of
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heartbeat, an artificial heartbeat.
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And when you do that, you can get
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dramatic changes in the image quality.
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This and this may be difficult to compare,
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but you can see that this and this,
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dramatic changes in the image quality.
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So here's another example.
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Again, this is a patient who came in for a pre-
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op TAVR, and this is the multi-phase image.
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No doubt, there is a lot of ghosting.
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And this is quite dramatic, and this is a
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problem because if you have ghosting you can
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overestimate the annular area and then end up
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implanting a valve that's too big for the patient.
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which can have its own consequences.
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So, again, you can see what the issue is.
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Looking at the ECG strip, there's just
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this one area that just got, um, missed.
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And, when we correct that, we can see very nice,
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crisp images which are a result of the ECG correction.
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This is also an interesting one,
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which, see this band over here?
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This band is because of an abnormal beat.
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And, let's see if you can spot that abnormal beat.
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Actually, you don't have to because what we've
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done is we've taken that abnormal beat out.
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See this line over here?
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That's taking it out, deleting it or disabling it.
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You can do either one.
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And you can see what has happened as a result of that.
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It's a dramatic change in the image quality.
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And even though we took it out, we actually made this
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heart rate more irregular, but it's better to have.
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Irregular and without the PVC because
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PVC doesn't really follow the same course.
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It's just something that confuses the system.
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So small changes resulting in dramatic differences.
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And here's an example again of ECG editing.
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We've got motion in the RCA that looks like it
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may be incorrectable, but you can see that you
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go back to the ECG and you can see a couple
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of problems where the arrow is pointing.
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of these abnormal beats, and what we've done
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there is just simply disabled the sync, and that's
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led to dramatic improvement in imaging quality.
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