Procainamide (Pronestyl)

Question 1

Class

Answer 1

Antiarrhythmic–class 1a

Question 2

Actions (2)

Answer 2

• Alters sodium conductance through the sodium (fast) channels of cardiac cells
• Decrease atrial and ventricular irritability:
  1) Decreases phase 4 depolarization (depresses automaticity)
  2) Increases threshold of excitability (depresses excitability)
  3) Prolong effective refractory period
  4) Reduces conduction velocity in atrium, Bundle of His, and ventricle

Question 3

Indications (3)

Answer 3

• Ventricular ectopy (PVCs, stable VT) refractory due to Lido
• VF and pulseless VT refractory due to Lido and Bretylium
• Wide complex PSVT

Question 4

Contraindications (3)

Answer 4

• 2nd and 3rd degree AV block
• Prolonged QT interval
• Torsades

Question 5

Side Effects (5)

Answer 5

• Hypotension
• Bradycardia
• Heart blocks
• Widened QRS
• Prolonged PR or QT interval