Avalon-H90 Clinical Value
Chest pain accounts for approximately 7 million annual visits to emergency departments (ED) in the United States, making chest pain the second most common complaint .
Chest Pain Patients (CPP) present with a spectrum of signs and symptoms reflecting the many potential etiologies of chest pain. Diseases of the heart, aorta, lungs, esophagus, stomach, mediastinum, pleura, and abdominal viscera may all cause chest discomfort. Non-cardiac chest pain (NCCP) is very common in the general population . 75% CPP patients will have a non-cardiac condition, however most of these will still follow the chest pain pathway and undergo serial cardiac biomarker testing to rule out an MI or other cardiac syndromes . When it comes to chest pain, the cardiologist's first priority is to exclude any acute life-threatening cardiovascular condition . These include acute coronary syndrome, aortic dissection, pulmonary thromboembolism, and pericardial tamponade. If these acute conditions have been excluded, evaluation for chronic ischemic heart disease or pericardial disease must be pursued .
Patient outcome has not been ideal for the majority of patients who experience delays in the emergency department (ED) before receiving definitive therapy. Furthermore, a significant number of patients with AMI (4% to 13%) are not diagnosed by the emergency physician [1-3]. These AMI patients, once inadvertently released home, have 11% to 25% risk of dying from the MI [2,3]. These patients are the most expensive cause of malpractice litigation against emergency physicians, comprising 20% of dollars paid for malpractice. - See more at: http://www.acep.org/Clinical---Practice-Management/Chest-Pain-Units-in-Emergency-Departments/#sthash.JZbl4W4s.dPaM5XFi.dpuf
If a patient with an AMI is treated within 70 minutes, the left ventricular damage can be minimized due to infarct abortion, and mortality decreases to 1.6% . If therapy is delivered after this time, mortality and morbidity from AMI rise dramatically, as significant irreversible myocardial damage has already occurred. - See more at: http://www.acep.org/Clinical---Practice-Management/Chest-Pain-Units-in-Emergency-Departments/#sthash.JZbl4W4s.dPaM5XFi.dpuf
There is a need in technology for ER and ED medicine that delivers results during minutes after patient admission, that could rule out patients with high and low risks cardiac event correspondingly with high negative and positive prediction values. According the references above, there is a demand of Emergency Medicine delivering test results such as SPECT does during the minutes but not hours. In fact, MCG is exactly what is needed. According the study provided by Cedar Sinai Medical Center , MCG data taken from the chest pain patients can deliver the similar result or better than SPECT in diagnostics of ischemic heart disease. Available MCG data was provided by an MCG system that took about 6-8 minutes of measurements (now reduced to 1 – 1.5 minutes in the new system), delivering analysis during next 3-5 minutes. Even though results were very promising, there were problems with system performance in close proximity of elevators, moving hospital personnel and activities in nearby rooms, creating a serious difficulty in using MCG in ER, ED or ICU departments.
Also those systems, requiring Liquid Helium, had to be refilled twice a week. Mesuron Inc. has developed sophisticated MCG system and software configuration that solved those problems completely. This new system operates without using the liquid helium (cooling provided by a cryocooler coupled with proprietary Mesuron technology that allows very effective removal of heat from the cooled volume -- another significant advantage unique to our system). Mesuron MCG system allows measuring the heart signal in real hospital environment in close proximity to all kinds of machinery, freight elevators, working printers, computers and moving hospital personnel.
Mesuron MCG system such as“Avalon-90” can deliver heart Ventricle Repolarization Dynamics Analysis (VRDA) during 3-5 minutes; that includes taking the cardiac data during only 90 seconds or less. The result of the VRDA is similar to what SPECT does. The reason for this similarity is clear: hypoxia of some region of the heart muscles manifests itself in both diagnostics. SPECT detects the regions of the heart with hypoxia (reduced delivery of blood supply) using the radioactive chemical containing Thallium that acts similar to oxygen. Scanning the heart, SPECT can identify regions of the heart with insufficient Thallium supply in heart muscles affected by insufficient blood supply.
MCG VRDA analysis detects the multidimensional dynamics of the electrical activity caused by differences in functions of Electrical Action Potential EAP of normal heart tissues and abnormal ones, with hypoxia. Interaction of functions of EAP of normal and affected regions is creating the repolarization dynamics that is different from the normal repolarization of the heart muscles activity. Mesuron’s MCG VRDA can detect Repolarization problem even without hypoxia event per say. EAP of heart muscles experienced with insufficient blood supply during prolong time also has different function due to changes in chemistry of muscles activities adapting insufficient blood supply. As a result, the MCG can detect abnormalities even with no presence of hypoxia at the time of measurements. That is why MCG results in CSMC study were so similar to SPECT, even when taking the MCG data on patients at rest.
Conclusion: MCG VRDA is a rapid noninvasive, no radiation, no contact, no pharmaceuticals, no physical exercise test delivering results with indications of high risk and low risk cardiac patients (related to ventricle repolarization abnormalities) with high positive and negative predictive values.
- Richard Niska, M.D., M.P.H., F.A.C.E.P.; Farida Bhuiya, M.P.H.; and Jianmin Xu, M.S.; Division of Health Care Statistics,
- Ronnie Fass1 and Sami R Achem2 Noncardiac Chest Pain: Epidemiology, Natural Course and Pathogenesis http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3093002/
- Backus et al. 2011; Rohacek et al. 2012; Six et al. 2012; Backus et al. 2013
- Kirsten Tolstrup, Bo E. Madsen, Jose A. Ruiz, Stephen D. Greenwood, Judeen Camacho, Robert J. Siegel, H. Caroline Gertzen, Jai-Wung Park, Peter A. Smars "Non - Invasive Resting Magnetocardiographic Imaging for the Rapid Detection of Ischemia in Subjects Presenting with Chest Pain" Cardiology 2006; 106:270-276 Read PDF file here Read Online here
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