KROK 1 2015 – Question 118 · KROK (Medicine) · Physiology
During ventricular systole, the cardiac muscle does not respond to additional stimulation because it is in the phase of:
- A. Hyperexcitability
- B. Absolute refractoriness
- C. Subnormal excitability
- D. Relational refractoriness
- E. There is no correct answer
Hint
Relate the long plateau of the ventricular action potential, and the state of the sodium channels during it, to the excitability of the myocardium throughout systole.
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