# PVC



## Chris EMT J (Mar 23, 2022)

I have a friend who has PVCs frequently. My friend said I could show his apple watch ECG. Now anyone want to try to identify what type of PVC.


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## Chris EMT J (Mar 23, 2022)

Also EMT-Bs you can try to give me a estimate heart rate or exact. And tell me how you did it.


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## E tank (Mar 23, 2022)

That's not a PCV


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## Chris EMT J (Mar 23, 2022)

E tank said:


> That's not a PCV


PVC? It's not? What is it?


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## Aprz (Mar 24, 2022)

He's probably joking. You said PCV and it's a PVC. Looks like you caught that mistake, but then still asked what it was for some reason. He could also be talking about the small blip just before the wide complex. If that's a p-wave, it could be an ectopic atrial beat (timed about the right time for the P-wave, but very different morphology from all the other P waves with a very short PR interval making the QRS occur earlier). Could be a PVC that interrupted atrial depolarization just as it was happening. Personally, I don't like to look THAT closely to an ECG or think that hard about an ECG, especially one from an Apple watch that's probably not that reliable. I mean look at the second and third beat at 1s and 2s, you can see an increase intrinsicoid period in the QRS complex with normal PR interval (looks like a delta wave from WPW, but normal PR interval). You can see that on different QRS complexes throughout this. Is it what your friend's actual ECG looks like or just an Apple watch? LOL. It probably is most likely a PVC still.

If there were multiple morphology, it would be multifocal PVC. If there was a PVC every other beat, it would ventricular bigeminy. If every third beat, ventricular trigeminy, and so on. Since we can only appreciate a single PVC here, I suppose you could say a unifocal PVC, but that's kind of redundant, superfluous. Sometimes we say interpolated PVC if it has no compensatory pause, but this does have a compensatory pause. So if it was me personally, I wouldn't try defining this PVC any further than just saying PVC.

You can sometimes tell the foci location based on if the PVC more closely resembles a left or right bundle branch block. If the foci originated from the left side of the heart, you'd see something like a right bundle branch block. If the foci originated from the right side of the heart, you'd see something like a left bundle branch block. Bundle branch blocks obvious have their appearance because the left or right side of the heart has a delay in conduction. When you're dealing with ventricular foci, they don't typically use "the highways" of the heart because they started off the highways already, off the road essentially. At the bottom of the screenshot, it says this closely resembles lead I. The QRS complex (or rS complex) is mostly negative so it could only have right axis deviation or extreme right axis deviation. Right axis deviation or extreme right axis deviation is very rare in left bundle branch blocks; The left ventricle is huge and the delay depolarizing the left side of the heart due to the block very commonly causes left axis deviation. This foci likely would have originated from the left side of the heart because of this, in my opinion. It's  generally useless know that and is "fun fact" (more useful to explain type of VT or accessory pathway, but this is just a single PVC).

Heart rate is between 71-75 beats per minute. See how it says 25 mm/s at the very bottom? That is the "paper" speed (no paper, lol). Each little box represents 1 mm. Each big box represents 5 mm. We count heart rate per minute. To convert 25 mm/s to minutes, you'd multiply that by 60 seconds. 25 mm/s x 60 seconds = 1,500 mm/minute. After every QRS complex, there is a space between the QRS complexes. That means you can divide 1,500 mm by the distance from one QRS complex to the next QRS complex (usually called the R to R interval, when using the R wave of the QRS complex to measure). The distance between this is between 20-21 mm. 1,500/20 = 75. 1,500/21 = 71. A lot of paramedics are trained to memorize 300, 150, 100, 75, 60, and 50. The reason they do this is because they measure in big box (5 mm each) instead of mm. Since 1 big box is  mm, you could convert the 1,500/RR interval in mm by dividing 1,500 by 5 (because 1 big box = 5 mm) to get 300/RR interval measured in big boxes. 300/1 = 300, 300/2 = 150, 300/3 = 100.... see the pattern?

In the end, this is from an Apple watch.... Not very reliable in my opinion. It's just a single beat that looks like a PVC to me. Really not that significant.


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## E tank (Mar 24, 2022)

Aprz said:


> He's probably joking.


I wasn't joking...thanks for the benefit of the doubt!  I did glance at that and see a PAC with an aberrantly conducted QRS. My error was in not considering the PR interval. Thanks for the lesson!


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## Chris EMT J (Mar 24, 2022)

Aprz said:


> He's probably joking. You said PCV and it's a PVC. Looks like you caught that mistake, but then still asked what it was for some reason. He could also be talking about the small blip just before the wide complex. If that's a p-wave, it could be an ectopic atrial beat (timed about the right time for the P-wave, but very different morphology from all the other P waves with a very short PR interval making the QRS occur earlier). Could be a PVC that interrupted atrial depolarization just as it was happening. Personally, I don't like to look THAT closely to an ECG or think that hard about an ECG, especially one from an Apple watch that's probably not that reliable. I mean look at the second and third beat at 1s and 2s, you can see an increase intrinsicoid period in the QRS complex with normal PR interval (looks like a delta wave from WPW, but normal PR interval). You can see that on different QRS complexes throughout this. Is it what your friend's actual ECG looks like or just an Apple watch? LOL. It probably is most likely a PVC still.
> 
> If there were multiple morphology, it would be multifocal PVC. If there was a PVC every other beat, it would ventricular bigeminy. If every third beat, ventricular trigeminy, and so on. Since we can only appreciate a single PVC here, I suppose you could say a unifocal PVC, but that's kind of redundant, superfluous. Sometimes we say interpolated PVC if it has no compensatory pause, but this does have a compensatory pause. So if it was me personally, I wouldn't try defining this PVC any further than just saying PVC.
> 
> ...


Ok. Yeah it is a apple watch but when he got diagnosed it was a holter monitor. Also very good explaining! Very impressive.


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