Which Blood Pressure Number is More Important?

The higher number (systolic) measures pressure when your heart contracts, and the lower (diastolic) reading measures the pressure when your heart relaxes. A recent study followed people with high blood pressure to see which people developed heart attacks (Hypertension, May 26, 2009). The authors found that the best predictors for future heart attacks are the systolic (heart contraction) blood pressure and pulse pressure (the difference between systolic and diastolic blood pressures). Evidently the higher your blood pressure rises when your heart contracts, the more likely you are to have a heart attack. Normally, the aorta is supposed to widen when the heart contracts to send a large amount of blood to your arteries. Those with the stiffest arteries that do not widen with each heart contraction are the ones most likely to suffer heart attacks. More on interpreting your blood pressure numbers