Arrhythmias Part 2

Question 1

What are the characteristics of multifocal atrial tachycardia?

Answer 1

• P waves of different morphologies
• Varying PR segment length
• QRS will be narrow
• Irregular rhythm
• HR > 100 = MAT
• HR < 100 = WAP (wandering atrial pacemaker)

At least 3 different P-wave morphologies must be present in the same lead.

Example: Normal P, Inverted P, biphasic P

Question 2

What are the characteristics of paroxysmal atrial tachycardia?

Answer 2

• Regular rhythm
• May not see P wave if buried in T wave
• Typical HR of 100-200
• Abrupt in onset
• Often difficult to discern from SVT.

Primary characteristic is its abrupt nature.

Inferior leads should always have normal P-waves.

Question 3

What is the primary discerning feature between atrial rhythms and junctional rhythms?

Answer 3

Junctional rhythms have no PR segment since they originate in the junction.

Question 4

What characterizes atrial fibrillation?

Answer 4

• Irregular rhythm with an irregular rate
• Potential lack of P-waves preceding a normal QRS.
• Inconsistent presence of P-waves.

Question 5

Where is the likely origin of AFib in the heart?

Answer 5

Pulmonary veins

Question 6

How does atrial flutter present?

Answer 6

• Organized version of Afib
• Appears as a sawtooth, rhythmic form.

Question 7

Afib vs Aflutter origin

Answer 7

Question 8

How do you determine whether aflutter is 3:1 vs 4:1?

Answer 8

Atrial rate divided by ventricular rate.

More of an FYI per prof rice.
Calculated by determining R-R for ventricular rate.
Calculated by determining P-P peaks for atrial rate.

Question 9

What are the characteristics of SVT?

Answer 9

• Regular rhythm
• Abrupt onset
• Abrupt cessation
• HR 150-250
• Includes junctional tachycardia, AKA AV nodal reentry tachycardia (AVNRT)

Still has a narrow QRS.

Question 10

What is considered a wide QRS?

Answer 10

3 small boxes or more.

Seen in ventricular arrhythmias.

Question 11

Describe a PVC

Answer 11

• Wide complex at least 3 small boxes wide
• Usually long, compensatory pause after
• Occurs EARLIER than the next beat.

Question 12

What is considered SR w/ multiple/frequent PVCs?

Answer 12

Occurring less than every 4th beat.

If faster, it could be bigeminy, tri, etc.

Can also be multifocal.

Question 13

Define VTach.

Answer 13

3 consecutive ventricular beats at a rate of at least 120 bpm.

Sustained > 30s

Question 14

What does Torsades look like and what is the treatment?

Answer 14

Treat with magnesium

Question 15

What is an accelerated idioventricular rhythm?

Answer 15

• Sustained VT at a slower rate (50-100)
• < 50bpm = idioventricular rhythm

Question 16

Describe Vfib.

Answer 16

• No true QRS complexes
• Coarse waveforms along baseline.

Causes SUDDEN DEATH IF NOT TREATED

Question 17

What is VT commonly confused with?

Answer 17

SVT w/ aberrancy.

VT is dangerous, so assume VT until proven otherwise.