Cardiology Ch 3 Flashcards

Set Details Share
created 1 year ago by nick_madon9
Sinus and atrial dysrhythmias
show moreless
Page to share:
Embed this setcancel
code changes based on your size selection


SA node

Located in the upper portion of the right atrium and is referred to as the primary pacemaker of the heart.



All cardiac rhythms except the normal sinus rhythm


Normal sinus rhythm

normal electrical conduction pathway. Both the R to R and the P to P intervals are normal

- regular rate of 60-100 electrical impulses per minute


Sinus bradycardia

A dysrhythmia that occurs when all electrical impulses originate from the SA node and follow the normal conduction pathway but the heart rate is slower than 60 impulses per minute.


Sinus tachycardia

Occurs when all electrical impulses originate from the SA node at a rate between 101-150 beats per minute.


Sinus arrhythmia

Occurs when the SA node initiates all the electrical impulses but at irregular intervals.

-P to P and R to R intervals change with respirations, producing an irregular rhythm.


Sinus exit block

Occurs when the SA node initiates an electrical impulse that is blocked and not conducted to the atria.


Sinus arrest

Occurs when the SA node does not initiate an electrical impulse

- Depolarization will not occur and the next expected complex will not be seen


Sick sinus syndrome

Used to describe a sinus rhythm with a pause

- Used to refer to any dysrhythmia caused by a disruption in the electrical conduction pathway of the atria.


Atrial dysrhythmias

SA node fails to generate an electrical impulse. any other pacemaker site within the atria is capable of initiating the impulse.


Premature atrial complex

An individual complex that occurs earlier than the next expected complex of the underlying rhythm

- Originates from any atrial site outside the SA node


Non-compensatory pause

Could indicate the development of increased irritability in the SA node, causing it to generate an impulse sooner than expected in response to the premature beat.

-Measurement will be less than two times the R to R interval of the underlying rhythm.


Compensatory pause

Measurement will equal at least two times the R to R interval of the underlying rhythm.

- SA node does not respond to the premature beat


Paroxysmal atrial tachycardia

The sudden onset of a tachycardia with a rate greater than 150 electrical impulses per minute.

- P wave occurs before every QRS complex.

- P wave may be hidden in the T wave of the preceding complex


Supraventricular tachycardia

When dysrhythmia fits all of the characteristics of a PAT/PSVT but the beginning of the dysrhythmia is not seen.

-P wave may be hidden in the T wave of the preceding complex because of the rapid rate of the SVT.


Atrial flutter

Occurs when a single irritable site in the atria initiates many electrical impulses at a rapid rate.

- Electrical impulses are conducted throughout the atria so rapidly that normal P waves are not formed.

-Flutter waves are formed instead.


Atrial fibrillation

An increased irritability of all the cardiac cells in the atria exists.

- atrial rate may be so fast that the atria may not completely empty and some blood may pool causing blood clots


Wolf-Parkinson-White Syndrome

Genetic condition that occurs when an electrical impulse follows an additional or abnormal electrical conduction pathway called the bundle of kent.


Delta wave

Bump seen in the slurred section of the QRS complex.

- formed by depolarization of the ventricles through the accessory pathway before the normally conducted electrical impulse can reach the ventricles.