What is the definition of diastolic blood pressure?

Diastolic blood pressure is defined as the pressure on arterial walls when the heart is at rest, specifically in the phase of the cardiac cycle known as diastole. During diastole, the heart relaxes and the chambers fill with blood, leading to a decrease in pressure within the arteries. This measurement reflects the lowest level of pressure within the arteries and is crucial for assessing cardiovascular health. Monitoring diastolic blood pressure helps in understanding the resilience of the arterial walls and the overall state of the cardiovascular system when the heart is not actively pumping blood.

It's important to distinguish this from other concepts; while systolic blood pressure represents the pressure in the arteries when the heart contracts and pumps blood, diastolic pressure gives critical insight into how well the arteries can sustain blood volume at rest.