KVV E-Modules

What is the normal resting membrane potential of a ventricular cardiac myocyte?

A: -40 mV B: 0 mV C: -90 mV D: +30 mV

Which ion is primarily responsible for the depolarization phase (Phase 0) in cardiac action potential?

A: K⁺ B: Ca²⁺ C: Na⁺ D: Cl⁻

Bradycardia is defined as a heart rate of:

A: <80 beats/min B: >100 beats/min C: <60 beats/min D: 60–100 beats/min

Bradycardia is defined as a heart rate of:

A: <80 beats/min B: >100 beats/min C: <60 beats/min D: 60–100 beats/min

Which phase of the cardiac action potential is referred to as the “plateau phase”?

A: Phase 1 B: Phase 2 C: Phase 3 D: Phase 4

What is the predominant ion movement during Phase 3 of the cardiac action potential?

A: Na⁺ influx B: Ca²⁺ influx C: K⁺ efflux D: Cl⁻ influx

Supraventricular arrhythmias originate from:

A: Ventricles B: Bundle branches C: Atria or AV node D: Purkinje fibres

Which of the following is NOT a typical symptom of cardiac arrhythmia?

A: Dizziness B: Palpitations C: Rash D: Syncope

What does a “broad QRS complex” on ECG most likely indicate?

A: Ventricular conduction abnormality B: Rapid atrial firing C: Supraventricular origin D: Normal conduction

Which class of antiarrhythmic drugs blocks β-adrenergic receptors?

A: Class I B: Class II C: Class III D: Class IV

Which ion has a higher intracellular concentration under resting conditions?

A: Na⁺ B: Cl⁻ C: K⁺ D: Ca²⁺