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Diagnostic Devices
Published in Laurence J. Street, Introduction to Biomedical Engineering Technology, 2023
As an example of ECG waveform (Figure 2.25) measurement and analysis, one parameter that is often measured is the time between the S and T parts of the ECG wave, referred to as ST segment analysis. This is a relatively straightforward portion of the ECG waveform to detect, and normally, it is curved slightly upward and is about 80 ms in duration. ST segment analysis looks at both the shape and duration of this section (Figure 2.26). If it is flat or sloping downward, or if it is at a lower level than normal, it may mean that blood flow to part of the heart muscles is restricted (cardiac ischemia). If the segment is elevated, it may indicate myocardial infarction (also called cardiac infarction or heart attack, though heart attack can describe other heart problems as well), where part of the heart muscle has necrotized (died) due to loss of blood supply.
Bench test for magnesium scaffold
Published in Yoshinobu Onuma, Patrick W.J.C. Serruys, Bioresorbable Scaffolds, 2017
Daniel Lootz, Wolfram Schmidt, Peter Behrens, Klaus-Peter Schmitz, Michael Haude, Ron Waksman
Intravascular stent implantation is a worldwide accepted minimally invasive procedure to treat cardiac ischemia caused by narrowed coronary arteries since the randomized studies BENESTENT [1] and STRESS [2] showed superiority over plain balloon angioplasty. Today permanent stents, with and without antiproliferative-drug-eluting coatings, are well established for keeping the treated vessel segments open [3,4]. The idea of a bioabsorbable vascular scaffold that alters its mechanical behavior during its lifetime in the human body has been present since the early days [1,3,5,6] of stent development and gaining increasing popularity. Bioabsorbable scaffolds should offer acute implantation properties comparable to permanent stents and subsequently degrade over time. Without the presence of any foreign irritations [7,8], the artery is allowed to return to its natural physiological state and a potential trigger for late restenosis is removed [9].
Cognitive Aids in Emergency Medical Services
Published in Joseph R. Keebler, Elizabeth H. Lazzara, Paul Misasi, Human Factors and Ergonomics of Prehospital Emergency Care, 2017
Keaton A. Fletcher, Wendy L. Bedwell
DSSs are located primarily in quadrant III, as they are designed to simplify cognition. The acute cardiac ischemia time-insensitive predictive instrument (TIPI; Selker et al., 1991) is a simple algorithm that combines seven variables that can be collected upon initial contact with the patient and provides a probability of acute cardiac ischemia. This decision aid can be incorporated into a digital program or hand calculated; either way, it simplifies the decision process of whether a patient should be admitted or triaged. EMS using this DSS need not know or be trained on the math or research that led to the development of the TIPI, nor could they be more effective without this cognitive aid. As such, the TIPI should and many other decision aids simplify cognition and allow EMS to rest upon the work and research of many others in order to rapidly deliver the best and most appropriate care.
Spatiotemporal regularization for inverse ECG modeling
Published in IISE Transactions on Healthcare Systems Engineering, 2020
Conventional ECG systems place ECG sensors at a very limited number of locations over the thorax and provide the cardiac electrical information with low spatial resolution. It has been suggested that high-resolution ECG mapping is more conducive to the diagnostic assessment of heart diseases such as acute cardiac ischemia (Herring & Paterson, 2006). ECG sensors placed at different locations on the torso surface respond to the cardiac electrodynamics differently. Researchers have developed the body surface potential mapping (BSPM) to provide a comprehensive 3D picture describing the electrical activity on the body surface projected from the heart using a large number (32-231) of ECG sensors (Bond et al., 2010; Lacroix et al., 1991; Rudy & Burnes, 1999). High-resolution BSPMs provide richer cardiac information than traditional ECG systems, and have been used to detect different heart diseases such as acute cardiac ischemia (Kornreich et al., 1993) and atrial fibrillation (Bonizzi et al., 2010).
Socialized occupational medicine in Israel: past, present, and future
Published in Archives of Environmental & Occupational Health, 2020
Lilah Rinsky-Halivni, Chaim Cohen, Shlomo Moshe, Eric Amster
Alternate stations throughout the factory were assessed in coordination with the employer. These included:A foundry where the worker had been previously employed. This work involved working in front of a furnace kept at a temperature of several hundred degrees and required the use of respiratory protection. At this station, two details drew the occupational physician’s attention. First, the worker’s shortness of breath upon exertion would make it difficult for him to use personal respiratory protection gear. Second, exposure to high temperatures could cause coronary vasodilation, leading to a decrease in cardiac perfusion.A paint hall – including dipping process in open vats using ceiling-mounted cranes. The work at this station does not require much exertion. However, one of the vats contains methylene chloride, which releases carbon monoxide that could exacerbate cardiac ischemia. This station was ruled out.The processing department, which includes machining work using open CNC (Computer Numerical Control) millers and lathes, saws with built-in suction mechanisms, and press for manual piercing. The operator could alternate between sitting and standing and would have to lift objects weighing up to 5 kilograms.
Vitamin D supplementation alters the expression of genes associated with hypertension and did not induce DNA damage in rats
Published in Journal of Toxicology and Environmental Health, Part A, 2019
Carla Da Silva Machado, Alexandre Ferro Aissa, Diego Luis Ribeiro, Lusânia Maria Greggi Antunes
The vitamin D3 deficient diet upregulated expression of nine genes in SHR rats (Ace, Agtr1b, Cacna1c, Drd5, Mylk2, Nostrin, Scnn1a, Scnn1g, and Sphk1) and six genes in normotensive WKY controls (Ace, Cacna1c, Ednra, Ephx2, Itpr1 and Itpr2). Ace was upregulated by vitamin D3 deficient diet in both SHR and normotensive WKY animals. The role of ACE in regulation of cardiovascular function and electrolyte homeostasis is well established, and ACE inhibitory molecules are commonly used in antihypertensive therapies (Cushman and Ondetti 1980; Danilczyk and Penninger 2006). Excess angiotensin II, ACE’s main active peptide, plays a critical role in cardiac ischemia occurrence, and our findings demonstrated that vitamin D3 deficiency increased Ace expression in both experimental models.