Wave travel and reflection in the arterial system

Abstract

Blood pressure indices reveal pertinent information regarding the risk factors associated with certain cardiovascular conditions. In the last decade, research has focused on determining which module of measurement is most relevant as well as exploring new investigative techniques to aid in detection and treatment of cardiovascular disease (CVD). The rates of isolated systolic hypertension, arteriosclerosis and other diseases associated with ageing continue to rise as the elderly population grows. The cuff sphygmomanometer only measures blood pressure in the brachial artery. Pulse wave analysis (PWA) is a noninvasive method of generating the ascending aorta pressure wave from the arterial pressure pulse measured in the carotid or radial artery. Pulse wave analysis identifies the effects of increased pulse wave velocity (PWV), an indicator of arterial stiffness, and an independent measure of cardiovascular risk. As there is a discrepancy between pulse readings at different sites, PWA is invaluable in providing information on the left ventricle and on large arteries. This measurement can reveal the unseen beneficial effects of antihypertensive drugs, as ascending aortic systolic and pulse pressure often decrease more than brachial pressure, and can indicate the presence of spurious systolic hypertension. The technique is not difficult to learn and results have been reproduced in several studies. Continuing research into PWA needs to be done, however, to assure the reliability of the measurements and minimize the possibility of incorrect readings.