Tachycardia

Question 1

What are narrow QRS complex tachycardic conditions?

Answer 1

• Sinus tach
• AVNRT
• AVRT
• MAT
• A Fib
• A Flutter

Question 2

What are wide QRS tachycardic conditions?

Answer 2

• AVRT antidromic (WPW)
• V Tach
• V Fib

Question 3

What is SVT, what does it look like on EKG and what are examples?

Answer 3

• Supraventricular tachy
• Regular, rapid rhythm
• Narrow QRS, no P waves
• Examples: AVNRT, AVRT, junctional tachy

Question 4

What does an SVT present as?

Answer 4

Sudden onset and ending of palpitations

Question 5

Management of persistent SVT (stable patients)

Answer 5

• Vagal maneuvers
• Carotid massage
• Adenosine
• CCB or BB

Question 6

Management of persistent SVT (unstable patients)

Answer 6

• Vagal maneuvers

- If unsuccessful, immediate DC cardioversion

Question 7

What is direct current (DC) cardioversion?

Answer 7

Conversion of cardiac arrhythmia to NSR using electricity

Question 8

What is the MC cause of SVT?

Answer 8

AVNRT

Question 9

What is AVNRT, who does it affect and what is it triggered by?

Answer 9

• Reentrant circuit around AV node tachy
• 75% female
• Triggered by exertion, caffeine, alcohol

Question 10

What is AVRT?

Answer 10

• Accessory pathway tachy
• Wide or narrow QRS
• Seen in WPW

Question 11

What are the types of AVRT?

Answer 11

• Orthodromic (narrow QRS)

- Antidromic (wide QRS)

Question 12

Treatment of orthodromic AVRT?

Answer 12

• Treat like SVT
• Vagal maneuvers, adenosine, CCB/BB for stable pts
• Immediate DC cardioversion for unstable pts

Question 13

What is antidromic AVRT?

Answer 13

• WPW with rapid rate
• Wide complex, fast rhythm
• Difficult to differentiate from V-Tach

Question 14

How to treat antidromic AVRT if you know it’s a pre-excitation syndrome:

Answer 14

• Immediate DC cardioversion in unstable pts
• Immediate procainamide in stable pts
• Then catheter RF ablation of accessory pathway for all

Question 15

How to treat antidromic AVRT in a conscious patient?

Answer 15

• Treat like stable V-tach

- ACLS protocol then RF ablation

Question 16

What is WPW syndrome?

Answer 16

• Pre-excitation syndrome involving accessory pathway
• 25-50% pts symptomatic
• MC PSVT which is usually AVRT
• Early childhood, early adulthood

Question 17

What is a potentially serious arrhythmia in patients with WPW?

Answer 17

AFib - may result in rapid ventricular response

Question 18

What is MAT and how to treat?

Answer 18

• Multifocal atrial tachycardia
• 3+ p wave morphologies
• Tx underlying conditions
• Verapamil, Flecainide or propafenone

Question 19

How to treat V-tach?

Answer 19

• If pulse present, DC cardioversion, ICD

- If pulseless, ACLS protocol

Question 20

What is non-sustained v-tach?

Answer 20

• 3+ PVCs

- Duration of less than 30 secs

Question 21

What disease is strongly associated with non-sustained V-tach?

Answer 21

Idiopathic dilated cardiomyopathy (80%)

Question 22

Management of non-sustained V tach?

Answer 22

• If infrequent, no intervention except optimize electrolytes, BB, manage underlying conditions
• If frequent, consider Amiodarone

Question 23

What is Torsades de pointes triggered by?

Answer 23

Hypokalemia
Hypomagnesemia
Drugs that prolong QTc

Question 24

What types of meds prolong QTc? What is the consequence?

Answer 24

• Antiarrhythmics
• Antipsychotics
• Abx (macrolides, quinolones)
• Antidepressants
• Can cause Torsades de pointes

Question 25

Treatment of Torsades de pointes

Answer 25

• Unstable pts: prompt defib

- Stable pts: IV magnesium, temp pacing if no response