Systolic blood pressure is the pressure during ventricular contraction.

• A. Pressure during relaxation
• B. Pressure during ventricular contraction
• C. Pressure during atrial contraction
• D. Pressure during isovolumetric period

Answer: (B)

The main idea here is that systolic blood pressure is the arterial pressure reached when the heart is actively contracting and pushing blood out into the aorta. As the ventricles contract, ventricular pressure rises; once the aortic valve opens and blood is ejected, arterial pressure climbs to its peak—the systolic pressure. After that, during relaxation, arterial pressure falls to the diastolic value. The phase where the ventricles contract but the aortic valve is still closed (isovolumetric contraction) raises ventricular pressure but does not yet produce the peak arterial pressure, so it isn’t what we mean by systolic blood pressure.