Which term is used to describe the contraction phase of the heart cycle?

The contraction phase of the heart cycle is referred to as systole. During this phase, the heart muscle contracts, pumping blood out of the heart and into the arteries. This is a crucial part of the cardiac cycle, as it is when the heart generates the pressure needed to circulate blood throughout the body, delivering oxygen and nutrients to tissues while also removing waste products.

The term 'systolic' specifically relates to the pressures measured during this contraction phase, often seen in blood pressure readings. When blood pressure is measured, the systolic pressure represents the highest level of pressure in the arteries when the heart contracts.

In contrast, diastole is the phase when the heart relaxes and fills with blood, fibrillation refers to a disorganized heart rhythm, and pulse indicates the rhythmic expansion and contraction of arteries as blood is pumped from the heart. These terms relate to different aspects of heart function and the cardiac cycle.