P1.06 THE ACCURACY OF CENTRAL SYSTOLIC BLOOD PRESSURE DETERMINED FROM THE SECOND SYSTOLIC PEAK OF THE PERIPHERAL PRESSURE WAVEFORM

Central blood pressure may be a better predictor of cardiovascular risk than peripheral blood pressure. The central systolic blood pressure (cSBP) can be estimated from the late systolic shoulder of the radial pulse waveform (pSBP2). We compared pSBP2 with cSBP derived by a generalized transfer function in a large cohort of subjects, across a wide age-range. We also compared pSBP2 with true central SBP (cSBPi) measured by cardiac catheterization. Non-invasive measurements were made by applanation tonometry using the SphygmoCor device. The aortic pressure waveform was derived from the radial waveform using a validated transfer function. cSBPi measurements were carried out in 38 subjects undergoing diagnostic cardiac angiography, and the radial artery pressure waveform was recorded simultaneously using the SphygmoCor device. Data from 1,880 subjects aged 18–85 years, yielded 10,269 individual observations. There was a strong correlation (r=0.99,P