ECG quiz #2 + answer

Re: ECG quiz #2 + answer

mariette asselbergs — Sun, 26 Jan 2014 21:01:01 GMT

+1 realty appreciated Mike!

Mariette

Re: ECG quiz #2 + answer

Tricia Goulden — Sun, 26 Jan 2014 20:55:47 GMT

Yes please!

Re: ECG quiz #2 + answer

Glen McIntosh — Sat, 25 Jan 2014 02:26:30 GMT

Hit me with your rhythm strip.

Re: ECG quiz #2 + answer

Linda Filshie — Sat, 25 Jan 2014 02:14:45 GMT

Yes please, keep 'em coming - I'm another lurker on this thread who didn't have much different to add to what had already been posted. I find the "clinical significance" bit most helpful.

Re: ECG quiz #2 + answer

Laurence Webb — Fri, 24 Jan 2014 22:50:06 GMT

Yes, more please. I didn't post an answer but I was broadly correct. Getting the reasoning behind the terminology is especially useful

Re: ECG quiz #2 + answer

Yantha Smyth — Fri, 24 Jan 2014 21:34:42 GMT

Yep, I am up for another!

Re: ECG quiz #2

John Flynn — Fri, 24 Jan 2014 19:35:36 GMT

Very intesreting, Mike.

Thanks for sharing that.

[quote user="Mike Martin"]

Ready for more....?

[/quote]

Always

(It's much more fun trying to do ECG interpretation when there's not a dog's life depending on me getting it right!)

Re: ECG quiz #2

Mike Martin — Fri, 24 Jan 2014 13:17:42 GMT

Thanks for participating.

The underling rhythm is a sinus rhythm (black text). But alternating with VPCs, on this section of the strip (red text). This is termed ventricular bigeminy.

In addition there are 4 VPCs in a run, which is termed a ventricular tachycardia (VT) or because it is short you can add the adjective - paroxysmal. The speed of the VPCs gets quicker with each beat and certainly, the 3rd and 4th VPCs are catching up, and superimposed upon, the preceding T-wave - this is termed R-on-T. Often considered a dangerous sign associated with an increased risk of degenerating into ventricular fibrillation (VF) and thus sudden death.

So not a nice ECG - but really needs a full 24 hour Holter to assess.

The rate is a difficult one in these with mixed rhythms. There are 3 sinus complexes in 3 seconds = 60/min. If there were not the VPCs would the sinus rhythm be double? Quite possibly. The combined sinus + VPC rate then is double at 120/min. However the VT is much faster. This is were an ECG slide rule can be useful. Or, this can be worked out by measuring the distance between 2 beats and divide this into 1500 (for a paper speed of 25mm/s). So take the distance between the 2 middle VPCs = 4mm. 1500 / 4 = 375 beats/min. So a particularly fast VT.

So the 'exam' answer: There is an underlying sinus rhythm alternating with VPCs, ie. a ventricular bigeminy, at an overall rate of 120/min. In addition there is one run of a fast paroxysmal VT with R-on-T at a rate of ~375/min.

VPCs can be cardiac and non-cardiac and in dogs I reckon its 50:50. The non-cardiac causes include various abdominal / medical conditions such as splenic masses, GDV, pancreatitis etc. The fast VT here however would bias me towards cardiac, as most non-cardiac ventricular rhythms are much slow.

In this instance, this was a young GSD with malignant ventricular arrhythmia syndrome. Most grow out of it, but sudden death can occur. This dog has no symptoms / no collapsing.

Paper here

Ready for more....?

Re: ECG quiz #2

Michael Woodhouse — Wed, 22 Jan 2014 21:35:02 GMT

[quote user="Mike Martin"]

Gosh, much less response than the first one. Have I pushed the limits too much? In many ways its a progression of the first one.

[/quote]

I think when people are in general agreement with the answers given then the thread goes quiet!

Them's what I know as a VPC

Re: ECG quiz #2

Yantha Smyth — Wed, 22 Jan 2014 10:58:51 GMT

This seems to have dropped off the active list, but do we get an answer soon?

Re: ECG quiz #2

John Flynn — Fri, 17 Jan 2014 12:09:22 GMT

Supraventciluar regular beat followed by PVC with one section of V-tach

I'd call that ventricular tachycardia if 3 or more beats running together.

...but am too lazy to look up Mike's excellent ECG interpretation handbook (which is one of the best thumbed texts in the clinic) to see if I'm right ;-)

I'm with the others who don't think that counting a heart rate off that trace is especially helpful, but if I'm going to try...

I'd discount the ventricular beats as I'm guessing being so premature that there wouldn't be time for decent ventricular filling prior to a contraction that might not be particularly effective anyhow and therefore only the supraventricular complexes shown are going to give any decent cardiac output. I make it 4 of them in 5 secs, so approx. 50bpm.

This one's looking more like might be worth treating as reasonable chance that arrhythmia is affecting cardiac output. If patient was symptomatic, then perhaps mexilitine?

Re: ECG quiz #2

Yantha Smyth — Fri, 17 Jan 2014 11:01:30 GMT

I think if you were listening to the heart, and didn't lose count with the irregularity, you would hear 150/ min, but there would quite likely be a pulse deficit as some of the VPCs may not generate an equivalent pulse.

Re: ECG quiz #2

Martin Atkinson — Fri, 17 Jan 2014 10:30:22 GMT

[quote user="Yantha Smyth"]I think the HR is approx 150/ min [/quote] It is if you count all the VPCs and ectopic beats. Maybe the choice of the word 'overall' is a bit ambiguous Mike, do you mean the underlying rate of normal complexes or everything including the VPC's and ectopics? The rate felt by pulse would be only the normal complexes.

Re: ECG quiz #2

Clive Ansell — Fri, 17 Jan 2014 10:30:17 GMT

I was just about to have a go :-)

There is a normal background sinus arrhythmia, with normal P-QRS-T complexes. 3 complexes in 3 seconds, so an estimated sinus rate of around 60bpm, so on the verge of being a sinus bradycardia?.

Following each normal P-QRS-T complex there is one, or a series, of what look like abnormal QRS-T complexes which seem to have no obvious preceding P wave. They seem to occur at a regular time interval following normal P-QRS-T complexes. Ventricular in origin.

There is a run of 4 abnormal complexes within 0.8s, so although over a very short time would equate to a rate of 300pm. Intermittent ventricular tachycardia.

Re: ECG quiz #2

Yantha Smyth — Fri, 17 Jan 2014 10:19:43 GMT

I think the HR is approx 150/ min There is a irregularly irregular rhythm There is initially a single VPC after each normal QRS - ventricular bigeminy Then there is a run of 4 VPCs - paroxysmal ventricular tachycardia? Since not 'sustained' Great idea Mike!

Re: ECG quiz #2

Martin Atkinson — Fri, 17 Jan 2014 09:51:34 GMT

Miscalculated rate by counting VPC's so now put it at 40-42 bpm. I suspect this a Doberman with dilative cardiomyopathy, I hope you're not waiting for us to diagnose it before you treat Mike otherwise it will dead if it doesn't get some pimobendan PDQ!

Re: ECG quiz #2

Mike Martin — Fri, 17 Jan 2014 09:17:56 GMT

Gosh, much less response than the first one. Have I pushed the limits too much? In many ways its a progression of the first one.

Re: ECG quiz #2

Martin Atkinson — Wed, 15 Jan 2014 12:33:30 GMT

Sinus arrhythmia with ventricular bigemeny (a VPC following every normal QRST) then a run of ventricular tachycardia, the shape of the ectopic beats varies in shape and amplitude which suggests they are multi-focal in origin and the T wave following the last normal QRS is negative when all the others are positive, all of which is very worrying. Rate measured by 2 normal QRS complexes with a heart rate calculator is 80-86, I presume we don't count the ectopics and the gap from the 3rd to the 4th normal QRS gives a rate of 55 bpm which I am discounting This dog (I presume its a dog buy the height of its R waves) has serious myocardial disease and is likely to go into VT and then VF rather soon unless someone intervenes very quickly!

Re: ECG quiz #2

Jenny Smith — Wed, 15 Jan 2014 11:21:51 GMT

Irregular rhythmn (eyeballed - 5 squares between first 2 normal QRS complexes, then 6, then 9).

QRS for every P, but not a P for every QRS. I think this is down to early, abnormal QRS complexes obscuring rather than truly absent p waves.

Abnormal QRS complexes present, all similar morphology so suspect all arising from the same orgin, one run of 4. T wave (?!) at the end of the last normal QRS complex is going the wrong way.

I would go for VPCs (again) but to me this case would be much more of a worry than the first one!

Re: ECG quiz #2

Hannah Wynne Richards — Wed, 15 Jan 2014 10:53:05 GMT

Again not a cardiologist, but I'd say short bouts of VPCs and reverse direction, so ectopic origin. Some form of ventricular myocardial problem. So far snapping out spontaneously, but 1 step away from ventricular fibrillation.

Wynne

Re: ECG quiz #2

Anthony Dennison — Wed, 15 Jan 2014 10:45:48 GMT

Setting myself up to be told I'm so wrong, but I need to practice my cardiology/ECG reading!

Irregularly irregular heartbeat, so would it be accurate to give a heart rate with just this short ECG printout to go by?

2 normal complexes each followed by what looks like a VPC, then after the 3rd normal complex a run of 4 VPCs, increasing in amplitude, so does that mean the contraction is increasing in strength, or that the start point of the PVC is moving towards one of the leads?

Would such a short run of VPCs count as ventricular tachycardia? I presume the fact that there are normal beats interspersed between the abnormal complexes would mean the cause could be DCM, or possibly myocarditis?