Searching for ST-segment elevation myocardial infarction markers by absorption spectra analysis of exhaled air samples

Abstract

\n \n \n Type of funding sources: None.\n Background. Myocardial infarction is one of the main causes of mortality and disability. The standard diagnosis of myocardial infarction is associated with cardiospecific enzymes blood sampling. At the same time, it is of interest to search for new non-invasive myocardial necrosis markers, and there are few data in the periodicals on exhaled metabolites in myocardial infarction patients.\n Purpose. Detecting specific molecules or their combination for ST-segment elevation myocardial infarction patients\xa0 in exhaled air by analyzing the spectroscopic characteristics of exhaled air samples.\n Methods. The target group included 17 patients. The control group included\xa0 18 healthy volunteers. Inclusion criteria for the target group: primary STEMI; admission within 12 hours from the onset of STEMI; age 18 and older. All patients underwent standard diagnostics of AMI, including determination of CPK, CPK-MB, troponin. Exclusion criteria: acute illness, or exacerbation of chronic, major surgery \xa01 month before myocardial infarction; severe lung pathology; congestive heart failure III, IV NYHA class; impossibility of air sampling due to various reasons.\n In parallel, on the 1st day of hospitalization, as early as possible, air samples were taken on fasting. To do this, the patient three times calmly, until the lungs are completely empty, exhales into the surrounding space, at the end of the third exhalation - into a one-off air intake, which then was closed hermetically.\n The absorption spectra of samples of exhaled air were determined using the method of laser optical-acoustic spectroscopy and using a system for terahertz spectroscopy with time resolution. A comparative analysis of the spectra of samples of exhaled air for the 1st and 2nd ranges was carried out.\n The obtained spectra of exhaled \xa0air \xa0samples were analyzed using the principal component analysis. Statistical data processing was carried out by the STATISTICA 10.0.\n Results. \xa0Absorption spectra of exhaled air samples were obtained in two ranges - infrared (range 1, wavelength: 2.5-10 μm - using the method of laser optical-acoustic spectroscopy) and terahertz (range 2, frequency: 0.3-2 THz - s using a terahertz time-resolved spectroscopy system). A comparative spectra analysis of exhaled air samples for the 1st and 2nd ranges was carried out. It is shown that in the Principal Component space of the vector set\xa0 of signs for the spectra of exhaled air samples in ranges 1 and 2, corresponding to healthy patients and patients with primary myocardial infarction, it is possible to perform a visual separation.\n Conclusion. With the help of optical-acoustic and terahertz spectroscopy, a specific combination of substances in the exhaled air for patients with ST-segment elevation myocardial infarction was found.\n