Noninvasive studies of central aortic pressure.

Our purpose is to review noninvasive methods for measuring central arterial pressure. Indices of central arterial pressure measured from central aortic and peripheral arterial waveforms have shown value in predicting cardiovascular events and death, as well as in guiding therapeutic management. This article reviews noninvasive techniques of measuring central arterial pressure that have been validated against intra-arterial pressure. This paper explains methods to derive central (aortic and carotid) pressure from radial and brachial sites. It focuses on specific issues of brachial calibration applied to carotid pressure waveforms, which were regarded as a surrogate of aortic pressures used in three major studies (Framingham, Asklepios, and Australian National Blood Pressure 2 studies). We explain why radial-based methods are superior to carotid-based methods for estimating central pressure. Physiological principles of pressure measurement need be satisfied to ensure accurate recording.