Which pressure is lowest during the cardiac cycle?

During the cardiac cycle, diastolic pressure represents the lowest pressure in the arteries. This pressure occurs when the heart's ventricles are relaxed and filling with blood, which allows the pressure in the arteries to drop. As the ventricles fill, the pressure in the arteries is maintained at a lower level compared to systolic pressure, which is the peak pressure exerted in the arteries during ventricular contraction.

In contrast, systolic pressure is the highest pressure in the arteries, occurring when the heart beats and pumps blood out of the ventricles. Central venous pressure measures the pressure in the thoracic vena cava and reflects the amount of blood returning to the heart and the pressure within the right atrium, but it is generally higher than diastolic pressure. Pulmonary artery pressure is also elevated during ventricular contraction but is lower than systemic arterial pressures. Therefore, diastolic pressure is correctly identified as the lowest pressure during the cardiac cycle.