Which phase of the cardiac cycle occurs immediately after systole?

The phase of the cardiac cycle that occurs immediately after systole is diastole. During systole, the heart muscles contract, allowing the chambers of the heart to pump blood out to the lungs and the rest of the body. Once this contraction is complete, the heart muscles begin to relax, which marks the transition into diastole.

Diastole is characterized by the filling of the heart chambers with blood. During this phase, the pressure in the heart decreases, allowing the atria and ventricles to expand. This is essential for the filling of the ventricles, preparing them for the next contraction during systole. It’s important to note that diastole is not just a passive phase; it includes the active contraction of the atria toward the end, but the general phase referred to is still diastole.

The other phases mentioned, such as isovolumetric relaxation and ventricular filling, occur during diastole but are more specific sub-phases. Isovolumetric relaxation occurs immediately after ventricular contraction when all heart valves are closed and the ventricles are relaxing, but before they fill with blood. Ventricular filling is the part of diastole where blood flows from the atria into the ventricles. Thus,