What is the difference between sinus rate and sinus rhythm? Inherently I am asking the difference between rate and rhythm and what that difference means in EKG's?
Thank you
Thank you
sinus rate vs. sinus rhythm?
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Well this is something that would be covered in page 1 of pretty much any cardio chapter of any physiology book...
But anyway, rate is how fast it is (BPM) and rhythm is whether it regular, irregular, regularly irregular or whathaveyou.
But anyway, rate is how fast it is (BPM) and rhythm is whether it regular, irregular, regularly irregular or whathaveyou.
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I hope that makes you feel better about yourself.
still, he's right. I don't mind answering very basic questions, but it does mean the person asking it didn't look up the basics themselves or is actually asking a more complex question than it appears and didn't word it well.
In the case of the latter, I'll go into it a bit more.
normal sinus rate is 60-100 bpm. It's not a normal sinus rate if it's not a sinus rhythm though. This means that the impulse has to originate from the sinus node. if it's going 60-100bpm in a regular rhythm and there are no p-waves, then you're looking at an accelerated junctional rhythm or some other rhythm that just happens to be going at that rate.
Sinus rhythms are regular, originate from the SA node, are seen in the p waves, and have a specific axis and appearance on an EKG. You can have a sinus rhythm that happens to be a tachy or bradyarrythmia, so this would be something on an EKG that is regular, has normal p waves, and has a rate that is not a normal sinus rate.
So you can have a normal sinus rhythm without a normal sinus rate, but you can't have a normal sinus rate without a normal sinus rhythm. In that case, it would be an atrial/junctional/ventricular rhythm with a normal or accelerated rate.
In the case of the latter, I'll go into it a bit more.
normal sinus rate is 60-100 bpm. It's not a normal sinus rate if it's not a sinus rhythm though. This means that the impulse has to originate from the sinus node. if it's going 60-100bpm in a regular rhythm and there are no p-waves, then you're looking at an accelerated junctional rhythm or some other rhythm that just happens to be going at that rate.
Sinus rhythms are regular, originate from the SA node, are seen in the p waves, and have a specific axis and appearance on an EKG. You can have a sinus rhythm that happens to be a tachy or bradyarrythmia, so this would be something on an EKG that is regular, has normal p waves, and has a rate that is not a normal sinus rate.
So you can have a normal sinus rhythm without a normal sinus rate, but you can't have a normal sinus rate without a normal sinus rhythm. In that case, it would be an atrial/junctional/ventricular rhythm with a normal or accelerated rate.
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👍 There's no such thing as a stupid question OP, but be aware that this is what most people will be thinking without saying so. And if you ask this kind of thing on rounds you can expect the ole' "Why don't you look that up and give us a presentation on it tomorrow!"
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😀
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Yea.. (lets face it people like to feel big)
Rate = # of beats per minute
Rhythm a little harder to define but, has to do more with S1, S2 sound, pattern of electric activity, even flow but over all the cadence is equated with normal PQRST complexes on EKG..
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my brief take:
rate - beats per minute (normal 60-100)
rhythm - how "orderly" the heart is beating, the pattern of the beats. On EKG regular would mean a P wave before every QRS complex and evenly spaced P waves, QRS complexes and T waves (along with other more specific criteria for "normal"). Abnormal would indicate any of many, many arrhythmias.
rate - beats per minute (normal 60-100)
rhythm - how "orderly" the heart is beating, the pattern of the beats. On EKG regular would mean a P wave before every QRS complex and evenly spaced P waves, QRS complexes and T waves (along with other more specific criteria for "normal"). Abnormal would indicate any of many, many arrhythmias.
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No. I was just pointing out that it would have been polite to read up on the topic before asking your peers something you didn't understand, rather than asking them for a definition that would have been easily been accessed had a tiny amount of research been done.
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It is actually a great question, as I don't have any sinus rate in my language, neither do the germans, and it's probably cos the two terms are identical.
Sinus tachycardia = p-waves normal, R-R regular, rate above 100.
Sinus bradycardia = p-waves normal, R-R regular, rate below 60.
Sinus rhythm = p-waves normal, R-R regular (within a %-age I have forgotten), rate within 60-100.
Sinus rate = just the effin same. The distinction according to this thread was that a rate above 100 would not be sinus rate, but sinus rhythm, but strictly, that would be a sinus tachycardia, thus sinus rate and sinus rhythm is interchangable.
Good Q, stupid terminology.
Sinus tachycardia = p-waves normal, R-R regular, rate above 100.
Sinus bradycardia = p-waves normal, R-R regular, rate below 60.
Sinus rhythm = p-waves normal, R-R regular (within a %-age I have forgotten), rate within 60-100.
Sinus rate = just the effin same. The distinction according to this thread was that a rate above 100 would not be sinus rate, but sinus rhythm, but strictly, that would be a sinus tachycardia, thus sinus rate and sinus rhythm is interchangable.
Good Q, stupid terminology.
rate and rhythm are not interchangeable because they mean two different things in english. rate is the frequency. rhythm is the pattern.
sinus tach, sinus brady, normal sinus rhythm, and sinus arrhtyhmia are all different types of sinus rhythms. A sinus rhythm = any rhythm that originates from the sinus node.
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AV block: rhythm originates from the sinus node - is it a sinus rhythm?
Sick sinus syndrome: rhythm originates from the sinus node - is it a sinus rhythm?
I still think it is a good question, and not as obvious as some believe.
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It is a good question. Yes, it originates in the SA node, but it's not a Normal Sinus Rhythm. You can tell it a sinus rhythm because of the P waves, but the P-R intervals tells you if there are any first, second, or third degree blocks.
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Yes, these are both examples of sinus rhythm, as the impulse is originating from the SA node. Furthermore, you can have SR with AVB (you can even have NSR with AVB). The rhythm is still sinus, as long as it is coming from the SA node. It doesn't matter if/when/how the impulses aren't conducted through the AV node - once again, as long as they come from the SA node. Which you can determine by the 1) presence and 2) axis of P-waves (should point roughly in the direction of lead II).
"Normal" is a different story. I usually avoid the whole "normal" debate altogether by saying: Sinus rhythm at blah blah blah BPM with blah degree AVB and blah blah blah.
a first degree block would still be a sinus rhythm, but i'm not sure i'd call a 3rd degree block a sinus rhythm. mostly because the ventricular beats themselves are not originating in the sinus node (although the atrial beats are). but this is just starting to become semantics, as you'd just call it an "A-V block", not a "sinus rhtyhm with A-V block"..when talking with your colleagues/patients.
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This whole discussion is about semantics. And 3rd degree AVB technically has 2 rhythms - sinus rhythm amongst the conduction and muscular cells of the atria, originating in the SA node and terminating in the direction of the AV node, and a junctional or ventricular escape rhythm originating somewhere south of the AV node and conducting throughout the ventricles.
So, "sinus rhythm" is still technically present in 3rd degree AVB. You see it as normal-looking P waves with regular P-P intervals and a normal P-wave axis, which implies that the pacemaker function of the SA nodal cells is intact, and that they are generating a regular impulse. That's all "sinus rhythm" means. However, the "rhythm" on the EKG does NOT necessarily correlate to what is going on in the rest of the heart - i.e. the contractile function, or, in the case of 3rd degree AVB, the conduction of the impulse through the AV node. For example, you can have sinus rhythm on the EKG, but have PEA.
All the "rhythm" tells you is where the impulse is being generated from, and, in some cases, what vector it follows - it is the difference in electrical potential between points on a straight line over time that registers as a peak or valley on your rhythm strip, which some of you refer to as a "pattern." Is it coming from the SA node, some ectopic place or large/small re-entrant loop in the atrium/junction/conduction system/ventricular wall? Maybe it's coming from lots of different ectopic places in the atrium (MAT), tiny uncoordinated re-entry loops all over the atrium (AFib), a re-entry loop in the AV node (AVNRT), or perhaps from a large loop in the ventricle (VT) but following different vectors each time the impulse leaves the site (Torsades).
I guess the actual wording is less important than actually understanding how to translate the squiggly lines you see on the EKG into anatomical and physiological concepts. I'm going to shut up now.
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Depends on the situation. Not knowing the actual wording can make you come across as uncertain, even though your electrophysiological knowledge is top-notch.
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Eh, whatever. Knowing the actual wording is sometimes just an exercise in academics. Knowing what it is, whether or not it's dangerous, and, most importantly, WHAT TO DO FOR IT is what's important. It's easy to lose sight of the practical aspects when learning how to read EKGs, especially at an advanced level.
