Systolic blood pressure is the pressure in the arteries when the heart beats and pumps blood. It is the higher number in a blood pressure reading, typically expressed in millimeters of mercury (mmHg). For example, in a reading of 120/80 mmHg, 120 represents the systolic pressure. This measurement is important because it helps assess the health of the cardiovascular system. High systolic blood pressure, known as hypertension, can increase the risk of heart disease and stroke. Regular monitoring can help individuals maintain healthy blood pressure levels and identify potential health issues early.