[Angie O'Plasty, RN]

*bump!*

Hoping the OP will come back and tell us what the answer is!

[Dinith88]

Thats a very bad question because there're way too many variables involved in an MI (one mi isnt the same as another mi, etc., etc.) Also, all those mentioned rhythms can affect people/mi's in different ways.

The best answer is PVC's. (unless they're RARE pvc's.) . Frequent PVC's in mi can degnerate into v-tach (3 beats is 'technically' a run). As you all know, ventricular ryhthms will drop your cardiac output much more significantly than atrial ones...AND pvc's/v-tach will/can more readily degenrate into v-fib.
And if the PVC's are multi-focal, it's even more ominous.

Yeah, PVC's are generally benign. But in the face of infarction/ischemia they need to be treated if occuring frequently.


NOW, if you said a) a-fib w/rates of 80, b)svt with rate of 200, c) rare pvc's , the answer is obviously going to be 'b' (SVT).

OR, a) a-fib w/rate of 170 in a patient w/ejection fraction of 60% b) svt w/rate 150 in a patient w/ef 60%, c) frequent pvc's in a pt w/ef 15%, palpitations, and dizziness (and mi)... i would be most concerned about c.

OR is the person holding a pressure w/the svt, a-fib, pvc's???

OR...what/where is the infarction occuring? And how extensive? ( non-qwave mi in a heart w/good ef? or did they knock out their entire LAD? Or is it left main (the widow maker?)??????????

See how there're too many variables to choose the 'right' answer with the limited info provided??

Also...know that by definition A-fib IS an SVT!!!! ('supra-ventricular' ('above the ventricles') simply means the bad rhythm is being driven by irritable atria) And is a blanket term encompassing a-fib, wpw, atrial tach, etc. Anything fast, narrow (usually too fast to determine accurately by ekg...thus the 'blanket' term)

[Dinith88]

Originally Posted by rjflyn

I'm gonna go with A-flutter. Pts with chronic a-fib have MI's all the time. SVT generally is an acute problem as previously mentioned and frankly I personally havent seen it much in the instance of acute MI, though it does happen. That said pure A-flutter just dosent occur on its own that often.

More frequently though MI patients just present in plain old sinus rhythms. Sinus tach alot of the time, I give lots of Lopressor to slow them down.

RJ

I'm not picking, i just disagree with your post. First off, a-fib and a-flutter (though techinically different) are very similar and treated the same way. If fact, you can even think of a-flutter as a more 'organized' a-fib. And...because a patient has a-fib does not mean they have coronary disease...or that thay have 'mi's all the time'. You can have widely patent coronary arteries and still suffer from a-fib...for various reasons. AND keep in mind that SVT can 'be' a-fib, or a-flutter.

And...lopressor is great but if an MI patient presents in cardiogenic shock and is tachy, 'lots of lopressor' would be a bad thing.

[TachyBrady]

I think the answer is SVT. Increased HR means increased oxygen demand by the heart. Blocked coronary arteries (MI) block oxygen delivery. The combination can extend infarction. Treatment of MI includes beta blockers which slow the HR (which eases the work of the heart), along with nitrates (for vasodilation), and anticoagulation among other things. I also think SVT prevents adequate perfusion to the coronary arteries due to decreased filling time but I can't remember if this occurs during systole or diastole. Either way, the coronary arteries have less time to perfuse with increased HR.

I don't think controlled fib or flutter affect MIs too much unless they are a new finding. PVCs are common in the normal heart and so it is entirely understandable that they increase in an irritated heart (MI). It is possible but not necessarily probable for PVCs to progress into Vtach.

Just my 2 cents.

P.S. Denith, Afib is not considered SVT unless the rate is greater than 150.

[Dinith88]

Originally Posted by Bernaboop

P.S. Denith, Afib is not considered SVT unless the rate is greater than 150.

umm..actually no. a-fib is never considered svt. a-fib is a-fib even if the rate is 300. a-fib is called svt when it is fast and you're uncertain of the actual rhythm.(when it is determined that the rhythm is a-fib, you can stop calling it svt) svt isnt a rhythm unto itself. svt is a blanket term for fast, narrow rhythms that are difficult to interpret by ecg/tele.

and, i still say that the op's question is a bad one d/t not enougfh info. your choice was good (svt) because it implies a fast rhythm (which is always bad for a heart, especially an mi). but..the op never states that the a-fib is 'controlled'...or how many pvc's are occuring....or how bad mi is...etc.

so...any of the choices can be 'right' considering the mystery additional/hypothetical information. it's nice that we can all be correct despite picking different answers

[Dinith88]

Originally Posted by Dinith88

umm..actually no. a-fib is never considered svt

to clarify, i meant that once the Dx of a-fib is determined, you can stop using svt, but it's still a 'type' of svt. (along with a-flutter, wpw, atrial tach, multifocal atrial tach, etc.)

[TachyBrady]

Originally Posted by Dinith88

to clarify, i meant that once the Dx of a-fib is determined, you can stop using svt, but it's still a 'type' of svt. (along with a-flutter, wpw, atrial tach, multifocal atrial tach, etc.)

Gotcha.

I also agree.... the wording of this question is too ambiguous. Under differing circumstances, any one of the answers could be considered "most significant". I did enjoy the discussion though.

[SEOBowhntr]

I would have to agree w/ Dinith that this is hard to answer without some more criteria involved. However, I think generally, I've rarely seen SVT in an ACUTE MI, most common rhythms I've seen are A-Fib (Mostly associated w/ RCA blockages), VT (Mostly associated w/ Ant. MI's w/ LAD blockage), and then Frequent PVC's (which often times seemed to be more associated w/ electrolyte abnormalities. I disagree w/ the "Atrial Flutter and Atrial Fibrillation are pretty much the same," because they really aren't. At least in Atrial Flutter you have some atrial contraction strength, whereas in Atrial Fibrillation, you often times have a severely diminished ventricular filling, along with the increased risk of a thrombus.

I also agree that if you cannot determine the rhythm w/ a rate >150, even if it is A-Fib or A-Flutter, it IS an SVT. However, I've seen many nurses and physicians give Adenocard to pt's that were clearly in A-fib, not a "true" SVT.

My .02.

Doug

[Indy]

I think it's a badly written question because we don't interpret a rythym alone, unless it's v-fib or true V-tach. (I say true because my monitor's computer program reads a lot of false vtach; bundle branch block, pacer spikes, you name it.) We need: RATE and rythym. So the teacher who wrote this question needs to go back to work a bit, I think.