Last update:
12-May-2011

Hypertension is a major risk factor for most cardiovascular diseases. Typically, it is identified by measuring blood pressure (BP) at the brachial artery, usually by cuff-sphygmomanometry. Although such a measurement may accurately determine brachial BP, it does not reflect central systolic BP or pulse pressure. This is mainly because the BP waveform is distorted as it travels outwards from the heart, due to the presence of wave reflections from the peripheral arteries and the spatial variation of geometrical and mechanical arterial properties. Due to this distortion, brachial BP provides an inaccurate measure of central aortic systolic pressure and pulse pressure. Central systolic BP is an essential factor in determining the cardiac function and work, while central diastolic BP may determine coronary flow to a greater degree than peripheral systolic and diastolic BP respectively. Accordingly, central (i.e. aortic or carotid) pressures are pathophysiologically more relevant than peripheral pressures and their accurate estimation by noninvasive techniques is clinically necessary, but challenging. This review presents the technology and the currently available methods that are used for the estimation of central BP, and discusses issues related to the methodological procedures, reproducibility, validity and limitations. Recent data supporting the independent clinical and prognostic value of central pressures are briefly discussed.

Key words: Applanation tonometry, Arterial stiffness, Pulse pressure amplification, Pulse wave analysis, Wave reflections.