mdcat logical reasoning MCQ #263

A patient with a history of cardiac arrhythmias is prescribed a medication that increases the duration of the action potential. Which ion channel is most likely affected?

mdcat logical reasoning MCQ #263

  1. Question 1

    Q1. A patient with a history of cardiac arrhythmias is prescribed a medication that increases the duration of the action potential. Which ion channel is most likely affected?

    • A) Calcium channels in the sinoatrial node
    • B) Potassium channels in the atrioventricular node
    • C) Sodium channels in the ventricular myocytes
    • D) Chloride channels in the atrial myocytes

    Answer: Potassium channels in the atrioventricular node

    Explanation: Increasing the duration of the action potential is most closely related to the effect of potassium channels, which regulate repolarization.