When is arterial pressure at its lowest?

When is arterial pressure at its lowest?

• A. As the ventricle relaxes (diastolic)
• B. Immediately after ventricle contracts
• C. During systolic peak
• D. At the start of atrial contraction

Answer: (A)

Arterial pressure is lowest during diastole, the period when the ventricle is relaxing. After the heart finishes ejecting blood, the ventricle relaxes and the aorta and arteries recoil, which keeps blood flowing but at a lower pressure. This diastolic pressure is the minimum value on the arterial pressure waveform. Immediately after the ventricle contracts, pressure rises into systole, so that isn’t the lowest. The systolic peak is the highest pressure, and the start of atrial contraction occurs during late diastole without driving arterial pressure to its minimum.

Arterial pressure is lowest during diastole, the period when the ventricle is relaxing. After the heart finishes ejecting blood, the ventricle relaxes and the aorta and arteries recoil, which keeps blood flowing but at a lower pressure. This diastolic pressure is the minimum value on the arterial pressure waveform. Immediately after the ventricle contracts, pressure rises into systole, so that isn’t the lowest. The systolic peak is the highest pressure, and the start of atrial contraction occurs during late diastole without driving arterial pressure to its minimum.