Cardiac Arrhythmias

Question 1

What is the function of the SA node?

Answer 1

It acts as the heart’s natural pacemaker, initiating regular electrical impulses.

Question 2

What is the role of the AV node?

Answer 2

It delays the impulse to allow complete atrial contraction before ventricular activation.

Question 3

Where is the Bundle of His located?

Answer 3

It extends from the AV node into the interventricular septum.

Question 4

What do Purkinje fibers do?

Answer 4

They ensure rapid and coordinated ventricular depolarization and contraction.

Question 5

What does the P wave represent?

Answer 5

Atrial depolarization.

Question 6

What is the duration of the QRS complex?

Answer 6

About 0.10 seconds.

Question 7

What does the PR interval reflect?

Answer 7

AV nodal conduction time, normally about 0.20 seconds.

Question 8

What does the QT interval represent?

Answer 8

Total duration of ventricular depolarization and repolarization.

Question 9

What is the RR interval used for?

Answer 9

Calculating heart rate.

Question 10

What does the T wave represent?

Answer 10

Ventricular repolarization.

Question 11

Define a cardiac arrhythmia.

Answer 11

Any deviation from the normal rate or rhythm of the heartbeat.

Question 12

What are the three main types of arrhythmia presentation?

Answer 12

Tachycardia, bradycardia, and irregular rhythm.

Question 13

What does enhanced automaticity lead to?

Answer 13

Ectopic pacemaker activity and arrhythmias.

Question 14

What is the role of conductivity in arrhythmias?

Answer 14

Impaired conductivity can cause blocks or re-entry circuits.

Question 15

What is refractoriness?

Answer 15

The period after depolarization when cardiac cells cannot be re-excited.

Question 16

Name a structural cause of arrhythmias.

Answer 16

Myocardial infarction or cardiomyopathy.

Question 17

List two electrolyte imbalances that can cause arrhythmias.

Answer 17

Hypokalemia and hyperkalemia.

Question 18

How can the autonomic nervous system contribute to arrhythmias?

Answer 18

Through increased sympathetic or parasympathetic tone.

Question 19

Name one congenital cause of arrhythmias.

Answer 19

WPW syndrome or other inherited electrical system disorders.

Question 20

What is idiopathic arrhythmia?

Answer 20

Arrhythmia with no identifiable cause.

Question 21

What heart rate defines bradyarrhythmias?

Answer 21

< 60 beats per minute.

Question 22

What heart rate defines tachyarrhythmias?

Answer 22

> 100 beats per minute.

Question 23

Name three supraventricular arrhythmias.

Answer 23

AFib, atrial flutter, AVNRT.

Question 24

Name two ventricular arrhythmias.

Answer 24

VT and VF.

Question 25

What are the ECG features of AFib?

Answer 25

Irregularly irregular rhythm, absent P waves, fibrillatory waves.

Question 26

What is the hallmark ECG sign of atrial flutter?

Answer 26

Sawtooth flutter waves.

Question 27

Describe the ECG of SVT.

Answer 27

Narrow QRS, regular rhythm, hidden P waves.

Question 28

Describe the ECG of VT.

Answer 28

Wide QRS, regular or slightly irregular, no P waves.

Question 29

What does the ECG of VF look like?

Answer 29

Chaotic, no identifiable QRS complexes.

Question 30

What are the three degrees of AV block?

Answer 30

1st (long PR), 2nd (dropped beats), 3rd (AV dissociation).

Question 31

What is a common symptom of arrhythmias?

Answer 31

Palpitations.

Question 32

Why might an arrhythmia cause syncope?

Answer 32

Due to reduced cerebral perfusion.

Question 33

How do arrhythmias cause fatigue?

Answer 33

Through inefficient cardiac output.

Question 34

What life-threatening condition can result from VT or VF?

Answer 34

Sudden cardiac arrest.

Question 35

What symptom may suggest ischemia-related arrhythmia?

Answer 35

Chest pain.

Question 36

What respiratory symptom can arrhythmias cause?

Answer 36

Shortness of breath.

Question 37

What is the clinical implication of AFib?

Answer 37

Increased risk of thromboembolic stroke.

Question 38

What causes dizziness in arrhythmias?

Answer 38

Reduced blood flow to the brain.

Question 39

What is the importance of an irregularly irregular pulse?

Answer 39

Suggestive of AFib.

Question 40

When is a bradyarrhythmia more likely to cause symptoms?

Answer 40

When cardiac output is significantly reduced.

Question 41

What is the gold standard for arrhythmia diagnosis?

Answer 41

ECG.

Question 42

What is a Holter monitor used for?

Answer 42

Continuous 24-48 hour rhythm monitoring.

Question 43

What is the function of an event monitor?

Answer 43

Records rhythm during patient-reported symptoms.

Question 44

How does echocardiography assist in arrhythmia evaluation?

Answer 44

Detects structural heart abnormalities.

Question 45

What is an EP study?

Answer 45

An invasive procedure mapping heart electrical activity.

Question 46

What is the initial management step for unstable arrhythmias?

Answer 46

Immediate cardioversion or defibrillation.

Question 47

What medications are used for rate control in AFib?

Answer 47

Beta-blockers, calcium channel blockers.

Question 48

What is catheter ablation?

Answer 48

A procedure to destroy abnormal conduction pathways.

Question 49

What is the role of anticoagulation in AFib?

Answer 49

To prevent stroke from thromboembolism.

Question 50

What is the function of an ICD?

Answer 50

It delivers shocks to stop life-threatening arrhythmias.