AST Surgical Technologist Practice Exam

In terms of blood pressure readings, what does the term "diastolic" refer to?

1. The pressure when the heart beats

2. The lowest pressure in the arteries during resting phase

3. The average pressure during the cardiac cycle

4. The pressure before the heart contracts

The correct answer is: The lowest pressure in the arteries during resting phase

Diastolic blood pressure refers to the lowest pressure in the arteries during the resting phase of the heart, specifically when the heart is between beats. This phase occurs when the heart's chambers, particularly the ventricles, are filled with blood and the heart muscle is relaxed. At this time, the pressure in the arteries decreases, allowing for a measurement of how much pressure various factors exert on the artery walls when the heart is not actively contracting. Understanding diastolic pressure is crucial for evaluating cardiovascular health, as persistently high diastolic readings can indicate underlying conditions such as hypertension. This reading, paired with the systolic measurement (the pressure during heartbeats), provides insight into overall heart function and vascular resistance. Consequently, identifying diastolic pressure as the lowest arterial pressure during this resting phase accurately captures the physiological events occurring within the cardiovascular system.