Help in understanding PVC, V-tach

[BillTheCat]

I read alot about runs of 3 PVCs in a row.  DOes this mean the the Ventricles contract 3 times in a row before the Atrium does?  

So like: A-V, A-V, A-V-V-V-PAUSE, A-V?

Or is it 3 PVCs/Pauses in a row like:  A-V-V-Pause, A-V-V-Pause, A-V-V-PAUSE, A-V?

If it is the first example you feel V-tach while taking your pulse?  Is so, what would it feel like?  I get runs of PVCs where I can feel my chest flutter, feel the thud and sometimes the pause but my heart rate is typically very steady.  Most of the time my HR is in the 60's or 70's when this happens (based on taking my pulse in my neck).  I will sometimes feel a PVC every other beat (Pulse, Pulse, PAUSE, Pulse, PAUSE, Pulse, PAUSE, Pulse, Pulse) for a run of  3 or so but again, my sensed HR using my finger is in the 60-80 range depending.

Thanks for any help in understanding this.

[is_something_wrong]

Another comment and a question, just to understand if I get this right:

When SA node fires (after the premature beat) Ventricles are still in their refractory period and cannot conduct the signal. Next atrial beat is unaffected, thus PVCs creating a perceived break similar to exact 2x RR. Right?

There is something I don't understand, though. If you have a PAC, as I understand, the signal will reach sinus node and "reset" it (count as if it just fired an impulse), and next beat will follow 1x RR after the PAC impulse.

http://www.cableguy.net/ECG/pac.gif

As we can see from this ECG, PAC compensatory pause is longer than 1x RR, and total time between "SA generated R's" (if that made any sense what so ever) is 2x expected RR's, though this is a PAC.

I experience this myself, as I've felt "skipped beats" feeling like a beat was just left out, and next one follows about where it should. This was actually PACs.

[Mom2four85]

funny I just posted yesterday about my vt episode I had yesterday - haven't had one in awhile so it was a bit scary...my icd didn't stop it...which means it probably was getting ready to kick my butt on the ground lol luckily it corrected itself

I may experience things a bit different because of my weird system, so this is just my experience.  Yesterday my heart started racing, checked my hr 115 - bp 95/70; stayed in tachycardia for a bit - 15 - 20 minutes or so and tried deep breathing, coughing but nothing helped.

I had 7 or 8 intense sharp pains like a horse kicking me in the chest - almost felt like my heart was stopping, got dizzy - lightheaded and my throat felt congested; like I couldn't breathe - SOB, I got clammy feeling (I don't sweat due to my ANS problems) then started shivering - my ANS/Heart craziness that I can't stand, then it stops as quickly as it starts.

When this happens I get so weak and feel like I've been ran over by a truck, not sure if this is due to my ans/heart problem combo or what. I went and laid down for a few hours, got up for lunch and was still weak; and went to lay back down.  Had another  episode around 12 pm and 230 pm;  I still felt really icky and weak all afternoon; still had tachycardia off and on and then I had another episode around 10pm last night that woke me up.

before my ablation I had tons of pvc's daily and felt them; after surgery I started having pac's which none of my tests caught previously, so I thought that was strange...there is a huge difference for me in pvc's and pac's

I've read that 3 pvc's in a row can be indicative of v-tach but not always necessarily so, depends on a number of factors [trying to find that link, will post it when I find it]  I know I've had couplets, triplets, salvo's galore, but don't always go into V-tach.

[is_something_wrong]

Great answer!

[itdood]

I think it would be too difficult to tell just from these sensation of beats and rhythm.  

I don't know personally what NSVT feels like.  I think I had it once but I'm not sure.  Unless it's caught on a holter it's pure speculation.  At the time my pulse OX meter went to 256 BPM for a very short time.  What I found out is that even the rate can vary, so it was impossible to tell what I felt.  I had the quick succession of thuds like you felt.  It lasted about 6 or 7 thuds for me.

I spoke with my doc after this, and we decided follow-up wasn't warranted unless it happened more frequently because I had just been through every test under the sun, some of them twice and we couldn't find anything wrong.

I know for sure I once had a couplet and my diary matched the holter.  It was a gigantic single thud for me.  

[BillTheCat]

Thank that helps alot.  One last question though, if V-tach was going on, and considering the pulse you feel is the ventricle contracting, would you feel your pulse go:

THUD--THUD--THUDTHUDTHUD (3PVC's in a row)----(PAUSE)--THUD(normal beat)?

[itdood]

The pause from a single PVC isn't because the SA node stopped firing or "reset".    The atria are still contracting at a normal pace.

The SA node keeps firing (thus the atria contract) at it's normal pace.  The atria contracting cause something called a "P-wave" on an EKG.  So think of the time it takes from Pwave to Pwave.  This interval stays constant.

The "pause" occurs because the PVC interferes with the normal SA -AV node beat coming its way.  It's still there it just doesn't reach the ventricle which is actually a good thing.  The next p-wave interval is the same, but that longer pause is there because of the early ventricular beat overriding the SA-AV beat.

Some folks can physically tell the difference between PACs and PVC, which I think is to be expected.  The Ventricles have much more muscle mass, so yea, you're going to feel a difference.

Sooo, with that said, if someone is in vtach there will still be SA node beats getting fired.  However they get buried in the chaos of the ventricles doing their own thing.  In certain lower-rate v-tach, the p-waves can be seen on EKG.  In a high rate v-tach, the p-waves will be there but probably impossible to see on an EKG.

What you feel in a beat is the Ventricle contracting.  Remember think muscle mass, the atria has much less.  Since the ventricle didn't get the regular SA node beat while it was off in left field doing its own thing, it has to wait for the next SA beat before you feel it again.  this is what we perceive as the "pause".

Hopefully this drawing works out

Lines (left out the AV node firing for the sake of simplicity)
1=SA node firing a beat
2=Atrium contracting
3=Ventricle contracting


NSR
SA-------SA-------SA-------SA-------SA
---A----------A---------A----------A---------A
------V---------V---------V----------V---------V


NSVT
SA-------SA-------SA-------SA-------SA
---A---------A---------A----------A---------A
-----VVVVV-pause--V---------V----------V


A single PVC
SA-------SA-------SA-------SA-------SA
----A---------A---------A----------A---------A
------V--V-pause------V----------V----------V


Couplet
SA-------SA-------SA-------SA-------SA
---A---------A---------A----------A---------A
-------V-VV-pause---V--------V----------V


Bigeminy (what your described as having)
SA-------SA-------SA-------SA-------SA
---A---------A---------A----------A---------A
------V---V-pause----V----------V--V--pause

[is_something_wrong]

Hi,
Ventricular Tachycardia is defined as 3 or more consecutive PVCs. It's usually a pause before sinus beats take over, similar to PVCs.

In other words: A-A-A-V-V-V-PAUSE-A-A-A.

What you are feeling is ordinary PVCs or PACs (impossible to say without ECG monitoring). I'm quite sure this is not VT. If it is a line of premature beats (which I doubt) it's anyway extremely more likely to be an atrial tachycardia (SVT) than VT.