12-lead ch.8 Flashcards Preview

12-leadECG > 12-lead ch.8 > Flashcards

Flashcards in 12-lead ch.8 Deck (26):

What are some irregularily, irregular rhythms?

Atrial fibrillation, MAT, WAP


What are some Irregularily, regular rhythms?

a pattern of this would be long long short, short short long such as in wenkebach or atrial flutter patterns.


Which questions should you ask yourself about p waves?

Do you see p waves? Are all the p waves the same? Does each qrs complex have a p wave? Is the PR interval constant?


Which questions should you ask yourself about the qrs?

Are the p waves and qrs associated with each other? Are the complexes wide or narrow? Are the qrs complexes grouped or not? Are there any dropped beats?


What can cause Sinus tachycardia?

medications or conditions that require increased cardiac output such as exercise, hypoxemia, hypovolemia, hemorrhage and acidosis.


What is the difference between a pause/arrest and a block?

A block occurs when the qrs is a dropped beat but the next beat resumes on cycle or is a multiple of the cycle in the case of two dropped beats. A pause would not occur regularily within that cycle.


How does a PAC occur?

What some pacemaker site in the atria fires faster than the SA node


Describe ectopic Atrial tachycardia.

Occurs when an ectopic atrial focus fires more quickly than the underlying sinus rate. ST and T wave abnormalities may be present transiently.


Which patients tend to have WAP/MAT

Patients with severe lung disease such as COPD.


Which HR is indicative of Atrial Flutter 2:1 conduction?

A ventricular rate of 150bpm. (atrial is twice as fast)


Describe Atrial Fibrillation.

Chaotic firing of numerous pacemaker cells in the atria.


Why are PJCs the same morphology of a normal QRS? What patterns can they occur in?

A PJC originates in the AV node and follows down the normal electrical conduction system of the ventricles. They can occur as Bigeminey and Trigeminey.


Describe the difference between a PJC and a junctional escape beat.

An escape beat does not fire prematurely and tends to occur after the regular interval because it allows time for the SA node to fire first, when it does not fire, the escape beat fires to ensure proper heart function.


In what instances would you see a junctional rhythm?

When the function of the SA node is absent or surpressed and can also occur in AV dissociation and third degree heart block.


Describe the difference between a PVC and a ventricular escape beat.

A PVC is a premature beat that should give compensatory pause after it occurred to allow the heart to repolarize. An escape beat however waits for other pacemakers to fire and when it does not, the ventricles kick out and fire a beat and results in no compensatory pause before the next normal beat.


What should you do in the case of idioventricular rhythms?

Wait to see if it resolves itself. NEVER USE ANTIARRHYTHMICS!


Describe a fusion beat.

A sinus beat would occur at some point where the impulse was allowed to go through the ventricles through the normal conduction system along with the ectopic arrhythmia.


Describe a capture beat.

A capture beat is a normal sinus beat within the context of Ventricular tachycardia.


How can you definitively diagnose Ventricular Tachycardia?

Fusion and capture beats within a wide complex tachycardic rhythm will help to diagnose VT.


Describe Brugada's sign of Ventricular Tachycardia

Brugada's sign is that the interval from the R wave to the bottom of the S wave is greater than .10sec.


Describe Josephson's sign of Ventricular Tachycardia.

Josephson's sign describes a small notching near the low point of the S wave.


What is the underlying arrhythmia in TDP?

An underlying prolonged QT interval.


What could Ventricular Flutter at 300bpm indicate?

WPW with 1:1 atrial flutter conduction.


What can cause 1st degree heart block?

Medications, vagal stimulation and disease.


What do you do if you can't tell if it's Mobitz I or Mobitz II?

Assume the worst - Mobitz II


What's the difference between AV dissociation and 3rd degree heart block?

If there are just as many P waves (1:1) as there are QRS complexes it's AV dissociation.