Systolic hypertension. Direct and indirect BP measurements

The BPs of each of 26 patients with systolic hypertension were simultaneously measured indirectly by the cuff-mercury sphygmomanometer (cuff) and directly by intra-arterial recording from a brachial artery. The systolic BPs recorded by the two methods were comparable, indicating that systolic hypertension can be reliably diagnosed by readings from the cuff alone. However, the average diastolic BP was significantly overestimated by the cuff. This error in turn led to an underestimation by the cuff of the pulse pressure and overestimation of the mean arterial pressure. Thus, the low intra-arterial (true) diastolic BP and wide pulse pressure make increased arterial stiffness a plausible contributing factor in the pathophysiology of systolic hypertension.