What is the relaxation phase of the heart, also known as the bottom number of blood pressure?

Diastole is the phase of the cardiac cycle when the heart relaxes after contraction. During this phase, the heart chambers (the atria and ventricles) fill with blood, allowing the heart to prepare for the next contraction. This relaxation is crucial for maintaining adequate blood flow and pressure throughout the circulatory system.

The bottom number of a blood pressure reading, known as the diastolic pressure, reflects the pressure in the arteries when the heart is in this relaxed state, emphasizing the heart's ability to refill with blood without exerting extra pressure.

Understanding diastole is important because it plays a key role in overall cardiovascular health. It indicates how well the heart can manage its filling time and maintain adequate blood circulation in contrast to the systolic phase, which is the phase of contraction where blood is pumped out of the heart. Thus, recognizing diastole as the relaxation phase enhances comprehension of cardiac function and blood pressure regulation.