A computer program for the peripheral pulse wave

A brief journey into the history of the arterial pulse

Objective. This paper illustrates the evolution of our knowledge of the arterial pulse from ancient times to the present. Several techniques for arterial pulse evaluation throughout history are discussed. Methods. Using databases including Worldcat, Pubmed, and Emory University Libraries' Catalogue, the significance of the arterial pulse is discussed in three historical eras of medicine: ancient, medieval, and modern. Summary. Techniques used over time to analyze arterial pulse and its characteristics have advanced from simple evaluation by touch to complex methodologies such as ultrasonography and plethysmography. Today's understanding of the various characteristics of the arterial pulse relies on our ancestors' observations and experiments. The pursuit of science continues to lead to major advancements in our knowledge of the arterial pulse and its application in diagnosis of atherosclerotic disease.

Digital pulse plethysmography (DPG) in studies of the hemodynamic response to nitrates--a survey of recording methods and principles of analysis

Digital pulse plethysmography (DPG) has proved a technically simple, noninvasive, sensitive and informative technique for studying the effects of nitroglycerin and other nitrates on peripheral arteries. The importance of performing nitrate evaluation by DPG mainly in elderly subjects is emphasized. On the basis of observations with DPG some indirect conclusions on the effect of nitrates on the coronary arteries are justified. A review, with recommendations based on own experience, is given of various recording techniques and principles of evaluating quantitatively the digital volume pulse contour, with special reference to the influence of nitrates on the position and appearance of dicrotism. DPG seems to be a convenient, noninvasive and helpful procedure in studies on the development of nitrate tolerance.

Computer evaluation of human circulation based on non-invasive methods

A discriminating program was developed on the basis of time, dynamic and simply calculated parameters of non-invasive tracings recorded in the supine position. Data were derived from ECG, PCG and the indirect carotid pulse curve. The optimal program, formed after 40 experimental processes, was in 85% agreement with the clinical diagnosis. To improve the decision process, we created a new 'test again' group, in addition to the healthy and sick groups. The 'test again' group included 16.5% of the examined subjects. At the same time, there was 75.6% agreement with the clinical diagnosis, and 7.9% disagreement. The risk factors, which could be demonstrated as part of the 'errors' called attention to undetected heart failure. The descriminating function found to be best, was fed into a small computer (R-10). Records for evaluation were entered on magnetic tape to the computer which measured automatically the necessary parameters and printed out the 'decision': 'healthy', 'test again!', or 'cardiac patient', as well as other data, such as systolic time intervals, etc. There is a wide potential application for automated computer system based on non-invasive parameters.