Other (Class V) Antiarrhythmics

Question 1

Digoxin MOA

Answer 1

-digoxin exerts direct parasympathomimetic effects via direct stimulation of the vagus nerve → 􏰀AV nodal inhibition

(“welcome to las VEGAS” sign)

Question 2

Digoxin may be used to treat ..

Answer 2

-useful in atrial fibrillation and flutter, not first line
(“many tv screens showing irregularly irregular rythm”)

-prevents rapid ventricular response in atrial fibrillation and flutter (rate control)
(“las vegas” sign shaped like metronome )

Question 3

Magnesium Can treat …

(“magnets”)

Answer 3

-useful for the treatment of certain arrhythmias (torsades)

• magnesium treats torsades de pointes
  (״Torn twisted torsades streamers״)

Question 4

Hyperkalemia can …

Answer 4

-induce arrhythmias
(“Banana dancer pointing up”)

-causes peaked T waves on ECG
(“Peaked streamer”)

Question 5

Hypokalemia can …

Answer 5

-induce arrhythmias, severe muscle weakness, and glucose abnormalities
(“female Banana dancer pointing down”)

-can induce U waves at the end of the T wave on EKG
(“Streamer with extra bump”)

Question 6

Adenosine MOA

Answer 6

-adenosine is a purine nucleoside
(“Purine shaped gate”)

-adenosine activates A1 (Gi) receptors on the myocardium and at the SA and AV nodes
(“A1 swing”)

-increases outward K+ current→hyperpolarization
(“Banana flying out of the cup”)

-suppress inward Ca2+ current
(“Falling calci-YUM ice cream”)

-decreases atrioventricular conduction
(“disconnected bottom of heart shaped lamp”)

-inhibits AV nodes
(“Note shaped dance floor”)

Question 7

Adenosine can treat ..

Answer 7

-first line agent for acute treatment of supraventricular arrhythmias (PVST)
(“Illuminated top of heart shaped lamp”)

Question 8

Side effects of Adenosine

Answer 8

-causes transient high grade heart block (direct av node inhibition for about 10s)
(“Hat blocking heart”)

-causes coronary dilation (mediated by A2 receptors)
(“Dilated coronary crown”)

-can cause cutaneous flushing
(“Flushed dancer”)

-can cause shortness of breath, chest pain, and impending sense of doom
(“Dancer clutching his chest)

-can cause fainting, headache, and hypotension
(“fainting female dancer”)

Question 9

the actions of adenosine are inhibited by…

Answer 9

-caffeine and theophylline (methylxanthines)
(“Energy drink blocking A1 gate”)