PAC's Vs PVC's Vs PSVTs Vs. SVT?

can someone please explain the difference between all of these

1. pvc is s singe previntricular contaction . this one i already know

2. pac is a single atrial contaction.  this one i know as well

3. psvt  what is this? i know it stands for paroximal supraventricular tachycardia but what exactly is it? does this have anything to do with premature ATRIAL tachycardia or is it completely different. if one were to get sinus tachy following a single pac would this constitute psvt?

4. svt i know it stands for supraventricular tachy but is it different then psvt? if so then how is it different?

5. atrial tachy. is this different than psvt or svt? and if so how does it differ?

6. how does sinus tachy differ from psvt? if a person gets a pvc or pac and then heart begins to race . you know race like after you run a race or whatever. but racing rhythm is sinus tachy does it still mean that its a atrial tachy because it follows a pac? or can it be fear from feeling the pac and heart races?

7. bigeminy and trigeminy does this only apply to ventricals or atria as well? how do these differ from psvts or svts?

[SillyHeart]

Premature atrial tachycardia is the same as SVT.  They are two terms for the same thing: a tachycardia originating in the atria (above the ventricles - or supraventricular).

Sinus tachycardia originates from the sinus node rather than from the atria.  A racing rhythm that originates from the sinus node is sinus tach whether a PAC preceded it or not because it's still originating from the sinus node, not from the atria.

[va_tony]

SVT is the abbreviation for supraventricular tachycardia and represents a number of different tachycardias (HR > 120/mim) that start in the atria. Sinus tachycardia is one type of SVT.  Other SVT's are AV nodal reentrant tachycardia (AVNRT), Wolff-Parkinson-White (WPW) Syndrome, rapid AV Nodal conduction, atrial flutter, atrial fibrillation, atrial bigeminy, etc. The P in PSVT stands for paroxismal meaning occasionally. This represents a short lived SVT (<1 day or so) that starts and stops on its own.  I have chronic afib that lasts for weeks. So I have AF and NOT PAF. If you experience a short lived sinus tachy (originates in the SA node, which is in the atria) it's technically PVST.

PAT or paroxismal atrial tachcardia is the same thing as PSVT (the supraventricular and the atrial are interchangeable).

Sinus Tachycardia are not normally triggered by PACs (premature atrial contractions).   PACs will at times trigger atrial flutter and atrial fibrillation (and atrial bigenimy, etc.). Sinus tachy starts in the SA node.  This can be due to either a problem with the SA node or with you autonomic nervous system (ANS).  There is a form of sinus tachy called inappropriate sinus tachycardia (IST) that  is characterized by fast tachy and at other time bradycardia (<60 beats/min).  This is generally caused by ANS problems.  This is also related (but not the same) as POTS (Postural orthostatic tachycardia), which may occur when you stand up.

And, of course, a racing heart caused by a panic attack is NOT sinus tachycardia. So any time fear and adrenoline enter the picture, it's not PSVT. Also when you exercise, the rapid heart rate is still considered normal sinus rhythm (NSR).

[va_tony]

I just checked on IST and it is NOT characterized by alternating tachy and brady--- that's called tachycardia-bradycardia syndrome. IST, is as the name implies an inappropriate tachy response to small amounts of exercise or stress.

[SillyHeart]

va_tony a racing heart caused by a panic attack is sinus tachycardia.

[va_tony]

I stand corrected.  One source describes sinus tachy as:

"Sinus tachycardia is usually a response to normal physiological situations, such as exercise and an increased sympathetic tone with increased catecholamine release—stress, fright, flight, anger. "

So, much of what I said about sinus tachy in my previous post really applies to IST.

[Michaelccc]

thank you for the input. yeah i agree with silly heart sinus tachy is the "normal" racing heart. whether exersize or fear or panic or whatever. its not an arrythmia. that is one thing i'm not afraid of. i always get that being a worrier or whatever. and i know most people dont think that psvt is anything to worry about it. but my docs always told me my racing heart is sinus meaning sinus tachy. few pvcs and pacs here and there started 4 months ago. not worried about those either. just wondering if i may have experienced psvt. reason i'm concerned is because it seems all these posts i'm reading everyone starts of with pac's pvcs then afibs then a tachys then vtachs. it just seems like pacs and pvcs are just the beginning. i don't know very confused here. for some reason i think i had psvt reason i suspect that is because a new study shows that psvt are confused for panic attacks so many times. not just a couple of times but tons of times. and if it is psvt i know at times it takes an ablation to cure. so there goes my concern. anyway my question is if i did have a psvt would the staff who take "event monitor" readings over the phone have informed me that i need to speak to my doc  ? or would they treat it the way they treat sinus tachy which is  "nothing to contact the doctor about at this time" answer?