Class 4 Anti-arrhythmics

Question 1

What is another name for Class 4 anti-arrhythmics?

Answer 1

Ca2+ channel blockers

Question 2

Name 3 Class 4 anti-arrhythmics.

Answer 2

1. Verapamil
2. Diltiazem
3. Amlodipine

Question 3

T/F: Verapamil and Diltiazem can be used to treat ventricular arrhythmias.

Answer 3

FALSE, they can only be used to treat supraventricular tachyarrhythmias.

Question 4

For dogs with supraventricular premature depolarizations or supraventricular tachycardia which class 4 anti-arrhythmic would you use and how?

Answer 4

In an ER you would use Esmolol and DILTIAZEM (Ca2+ channel blocker that prolongs the refractory period and slows conduction through the AV node) there is an IV and oral form.

Question 5

In a dog with a-fib with normal heart function but the rate is up (>150 bpm) in order to slow the ventricular response rate you would give…

Answer 5

Diltiazem and a beta blocker

Question 6

In a dog with a-fib and decreased heart function and the rate is up (>150 bpm) in order to slow the ventricular response rate you would give…

Answer 6

Digoxin AND Diltiazem and a beta blocker

Question 7

In a cat with a-fib which is usually caused by HCM you would give…

Answer 7

Diltiazem and a beta blocker (Propranolol)