During which phase of the cardiac cycle does diastolic pressure occur?

• A. During heart contraction (systole)
• B. During valve opening
• C. During heart relaxation (diastole)
• D. During atrial contraction

Answer: (C)

Diastolic pressure is the arterial pressure that remains during the heart’s relaxation phase, when the ventricles are filling. After the heart finishes contracting and ejecting blood (systole), the ventricles relax and the aortic valve closes. The arteries then recoil, keeping pressure present but at a lower level until the next beat. This lowest arterial pressure occurs throughout diastole, including the later phase when the atria contract to top off ventricular filling. That’s why the diastolic pressure is the lower number in a blood pressure reading and is best described as occurring during heart relaxation.

So, this is not during contraction, and it isn’t tied to valve opening. It aligns with the period of diastole, when the heart is relaxing and refilling.