Thursday, March 14, 2019
Theory of the P wave detection The algorithm first finds the the possible positive and negative wave peaks based on zero transition searching, then validates them with comparing to reference P waves. The P wave detection needs high amplitude resolution. This value is better, than 0.6 uV / bit in the Cardiospy system. With this resolution and the effective filter system which uses wavelet transformation, the Cardiospy system is able to detect P waves less than 50 uV of amplitude. Validation of the P wave detector The validation is carried out on 10 pcs 12 channel and 10 pcs 3 channel ECG reference records. The reference records include the P wave annotation. 12 of the 20 records are taken from the MitBih database, 8 records are taken from the Labtech database (30000 – 30007). 12 ch records s0014lre, s0292lre, s0302lre, s0331lre, s0364lre, s0422_re, s0431_re, s0437_re, s0549_re, s0550_re 3 ch records mgh001, mgh007, 30000, 30001, 30002, 30003, 30004, 30005, 30006, 30007 Validation result: Sensitivity: 95.42% Positive predictivity: 97.16%
Saturday, February 2, 2019
Advancements In Pulse Wave Velocity Measurement Jan 29, 2019 1:58:50 PM by Sarah Goodman | what is pulse wave velocity, research, aortic pulse wave velocity, aorta, aortic stiffness, study, health technology As a “hallmark of aging" the measurement of aortic stiffness has been changing the way that academics approach aging and mortality. The aorta, the body’s largest artery, is a prime subject for the measurement of arterial stiffness as well as an indicator of overall cardiovascular health and biological age. Aortic stiffness is determined by a variable called aortic pulse wave velocity (AoPWV). The stiffer the aorta, the less elastic the arterial walls become and the more quickly blood will travel through the body’s vasculature. A higher AoPWV indicates stiffer arteries, due in part to aging, sedentary lifestyle, poor diet, flexibility, smoking, and genetic factors. With a single measurement of AoPWV, it is possible to measure aortic stiffness and therefore determine a wealth of information about an individual’s biological age and overall health. Luckily, a number of tools exist allowing medical professionals and individuals alike to monitor aortic stiffness in the quest for increased longevity and a longer, healthier life. Below are 6 examples of the technology available to measure aortic stiffness, for both medical and consumer use. 1. SpyhgmoCor SphygmoCor technology, the gold standard of aortic stiffness measurement, is a medical device developed by AtCor Medical. AoPWV is measured utilizing waveform analysis, measurements taken from sensors on both the carotid artery in the neck, as well as the femoral artery in the leg. The Sphygmocor device is primarily used for scientific research. This device rings in at about $25,000. 2. iHeart Internal Age? iHeart Internal Age is the world’s first consumer technology to measure Aortic Pulse Wave Velocity. This fingertip device works with a mobile application on iOS or Android and calculates a user’s Internal Age by measuring AoPWV. The user then takes positive steps to improve health and decrease aortic stiffness and lower Internal Age. Advancements in technology and AoPWV measurement have made it possible for companies like VitalSines to provide the iHeart Internal Age device and mobile application for general consumer use. At only $149 USD, this device is available worldwide in order to make measurements of aortic and arterial stiffness more accessible for those who wish to take control of their heart health. 3. Meridian Digital Pulse Analyzer Another device frequently praised by doctors is the Meridian Digital Pulse Analyzer, which is capable of detecting cardiovascular problems in their earliest stages. Like SphygmoCor devices, this digital pulse analyzer utilizes the concepts of PWV and waveform analysis to measure arterial stiffness. At $400 per month, it’s a viable option for medical office use. However, due to its cost, the utility of this device is not for individuals. 4. Laser Doppler Vibrometry Innovative strides in the development of medical technology are being taken all the time, as demonstrated by this laser doppler vibrometry device developed under the Cardis Project assisted by IMEC in Europe with success in early clinical trials. This device, which is roughly the size of a hairdryer, shows promise for health professionals as a portable screening tool capable of measuring aortic stiffness in large numbers of patients. 5. Complior The Complior device from Alam Medical, a France-based company, has been available since 2011 as another reliable and non-invasive option for the measurement of PWV and arterial stiffness. It is available only by special order for medical use. 6. Arteriograph Similarly, renowned institutions around the world are using Arteriograph, made in Germany by Tensiomed, as a device to quickly and accurately measure arterial stiffness. This device, while preferred by many medical professionals for use in their practices, is for medical use only and not available for commercial or at-home use. What Does This Mean For The Consumer? Despite the increasing amount of research on the importance of AoPWV and arterial stiffness as a measurement of biological age, products designed for individual consumer use are much less prevalent than the expensive devices designed for use solely by medical professionals. We are looking forward to seeing the advances in aortic stiffness measurement as technology continues to advance. Author: Sarah Goodman Sarah is the Chief Operating Officer of VitalSines, makers of iHeart Internal Age?. Sarah's background is in marketing, publicity, fitness, and nutrition. She has worked with the iHeart Team for five years and is passionate about helping people live longer and healthier lives.