Tachyarrhythmias (Wide QRS)

Question 1

What are ventricular premature beats characterized by on an ECG?

Answer 1

Full compensatory pause between normal beats

Ventricular premature beats may not require therapy, just beta blockers for symptomatic treatment.

Question 2

List some causes of ventricular tachycardia (VT).

Answer 2

• CAD
• MI
• CHF
• Hypoxia
• Hypokalemia
• Digitalis
• Prolonged QT

CAD: Coronary Artery Disease, MI: Myocardial Infarction, CHF: Congestive Heart Failure.

Question 3

What is the treatment for unstable ventricular tachycardia?

Answer 3

Electrical cardioversion (200J mono or 100J bi)

Electrical cardioversion is used to restore normal heart rhythm.

Question 4

What are the acute treatments for ventricular tachycardia?

Answer 4

• Amiodarone
• Lidocaine
• Procainamide

These medications are administered intravenously.

Question 5

What is the chronic treatment for ventricular tachycardia?

Answer 5

Implantable cardioverter defibrillator (ICD)

An ICD is used to monitor and correct life-threatening arrhythmias.

Question 6

What is Torsades de pointes?

Answer 6

VT with sinusoidal oscillations of QRS height

Question 7

What causes Torsades de pointes?

Answer 7

Prolonged QT, which can be congenital or drug-related

Question 8

Name a class of drugs that can cause Torsades de pointes.

Answer 8

Antipsychotics

Question 9

Give an example of an antipsychotic that can lead to Torsades de pointes.

Answer 9

Chlorpromazine or haloperidol

Question 10

What class of anti-arrhythmic drugs can cause Torsades de pointes?

Answer 10

IA, IC, and III

Question 11

List one IA anti-arrhythmic drug associated with Torsades de pointes.

Answer 11

Quinidine or procainamide

Question 12

List one IC anti-arrhythmic drug associated with Torsades de pointes.

Answer 12

Flecainide

Question 13

List one III anti-arrhythmic drug associated with Torsades de pointes.

Answer 13

Amiodarone

Question 14

What class of antibiotics can cause Torsades de pointes?

Answer 14

Macrolides and fluoroquinolones

Question 15

Name one macrolide antibiotic that can lead to Torsades de pointes.

Answer 15

Erythromycin or clarithromycin

Question 16

What is the treatment for Torsades de pointes?

Answer 16

IV magnesium (1-2g bolus)

Question 17

Fill in the blank: Torsades de pointes is characterized by _______ oscillations of QRS height.

Answer 17

sinusoidal

Question 18

True or False: Torsades de pointes can be caused by congenital factors.

Answer 18

True

Question 19

True or False: All drugs causing Torsades de pointes are related to anti-arrhythmic medications.

Answer 19

False

Question 20

What does Torsades de pointes (TdP) mean?

Answer 20

Twisting of the points

Question 21

What type of tachycardia is Torsades de pointes?

Answer 21

Polymorphic ventricular tachycardia

Question 22

What is a key characteristic of the ECG pattern in Torsades de pointes?

Answer 22

Rapidly oscillating QRS complexes that appear to twist around the baseline

Question 23

What is the typical QTc duration associated with Torsades de pointes?

Answer 23

0.45 seconds or longer

Question 24

What is the typical heart rate during Torsades de pointes?

Answer 24

Exceeding 200 beats per minute

Question 25

What is the significance of absent P waves in Torsades de pointes?

Answer 25

Indicates the arrhythmia originates from the ventricles

Question 26

What phenomenon can trigger Torsades de pointes?

Answer 26

R-on-T phenomenon

Question 27

What is the R-on-T phenomenon?

Answer 27

An early beat occurs during the relative refractory period of the T wave

Question 28

Who is at higher risk of developing Torsades de pointes?

Answer 28

Individuals with long QT syndrome (LQTS)

Question 29

What are some treatment options for Torsades de pointes?

Answer 29

* Intravenous magnesium * Correction of electrolyte imbalances * Antiarrhythmic medications * Cardioversion or defibrillation

Question 30

True or False: Torsades de pointes can be life-threatening if not treated promptly.

Answer 30

True

Question 31

Fill in the blank: Torsades de pointes is characterized by _______ QRS complexes.

Answer 31

rapidly oscillating

Question 32

What is crucial for timely diagnosis and treatment of Torsades de pointes?

Answer 32

Understanding the ECG features and potential triggers

Question 33

What is Preexcitation syndrome also known as?

Answer 33

Wolff-Parkinson-White (WPW) syndrome ## Footnote WPW is characterized by an accessory pathway that allows for abnormal conduction between the atria and ventricles.

Question 34

What is the pathophysiology of Preexcitation syndrome?

Answer 34

Conduction through an accessory pathway between atria and ventricles ## Footnote This abnormal conduction can lead to rapid heart rates and arrhythmias.

Question 35

What is the characteristic ECG finding in Preexcitation syndrome?

Answer 35

Short PR interval (<0.12s) and slurred upstroke in QRS (delta wave) ## Footnote The delta wave is indicative of early ventricular activation due to the accessory pathway.

Question 36

Fill in the blank: The PR interval in Preexcitation syndrome is _______.

Answer 36

shorter than 0.12 seconds

Question 37

What does the 'delta wave' represent on an ECG?

Answer 37

Slurred upstroke in QRS complex ## Footnote The delta wave indicates preexcitation due to the accessory pathway.