Infrared Spectroscopic Study and Mathematical Simulations of Carotid Atherosclerosis.

BACKGROUND/AIM: The pathogenesis, treatment and prevention of atherosclerosis continue to be the subject of intensive research and study by the scientific community. Based on Fourier-transform infrared spectra and 3D-Doppler echogram, we attempted to develop a computational simulation model for predicting the association of atherosclerotic risk factors with pathogenic molecular structural changes. MATERIALS AND METHODS: Atheromatic carotid arteries from 56 patients (60-85 years old) were used as samples. Color 3D-Doppler echogram screening was performed on all patients preoperatively. Each infrared spectrum consisted of 120 co-added spectra at a spectral resolution of 4 cm-1 Results: The infrared spectral analysis reveals 'marker bands', such as the 1,744 cm-1 band assigned to aldehyde formation and to the 'fingerprint' digital spectral region of 1,050-1,169 cm-1, characteristic of the presence of advanced glycation end products (C-O-C). The accumulation of calcium phosphate salts increases the formation rate of stenosis. The critical point of stenosis risk starts at about 45%, while when stenosis is over 60-70%, the risk of ischemic stroke or other major adverse cardiovascular events increases dramatically. CONCLUSION: Fourier-transform infrared spectroscopy and mathematical simulation models showed that carotid artery stenosis over 45% reduces the blood flow rate, while stenosis over 65% dramatically increases the hemodynamic disturbance, with a parallel increase the rate of ischemic stroke or other major adverse cardiovascular events.

"Missing" acute coronary syndrome hospitalizations during the COVID-19 era in Greece: Medical care avoidance combined with a true reduction in incidence?

BACKGROUND: Reports from countries severely hit by the COVID-19 pandemic suggest a decline in acute coronary syndrome (ACS)-related hospitalizations. The generalizability of this observation on ACS admissions and possible related causes in countries with low COVID-19 incidence are not known. HYPOTHESIS: ACS admissions were reduced in a country spared by COVID-19. METHODS: We conducted a nationwide study on the incidence rates of ACS-related admissions during a 6-week period of the COVID-19 outbreak and the corresponding control period in 2019 in Greece, a country with strict social measures, low COVID-19 incidence, and no excess in mortality. RESULTS: ACS admissions in the COVID-19 (n = 771) compared with the control (n = 1077) period were reduced overall (incidence rate ratio [IRR]: 0.72, P < .001) and for each ACS type (ST-segment elevation myocardial infarction [STEMI]: IRR: 0.76, P = .001; non-STEMI: IRR: 0.74, P < .001; and unstable angina [UA]: IRR: 0.63, P = .002). The decrease in STEMI admissions was stable throughout the COVID-19 period (temporal correlation; R2 = 0.11, P = .53), whereas there was a gradual decline in non-STEMI/UA admissions (R2 = 0.75, P = .026) following the progressively stricter social measures. During the COVID-19 period, patients admitted with ACS presented more frequently with left ventricular systolic impairment (22.2 vs 15.5% control period; P < .001). CONCLUSIONS: We observed a reduction in ACS hospitalizations during the COVID-19 outbreak in a country with strict social measures, low community transmission, and no excess in mortality. Medical care avoidance behavior is an important factor for these observations, while a true reduction of the ACS incidence due to self-isolation/quarantining may have also played a role.

Oxidative stress in ageing and disease development studied by FT-IR spectroscopy.

FT-IR spectroscopy was used to investigate the effect of oxidative stress and to approach the mechanism on cancer bone demineralization, aortic valve mineralization and heterotopic ossification on disease development. The FT-IR spectra obtained from paediatric, adult bone and ex vivo irradiated adult healthy bone with a dose of 20Gy were compared with those of healthy bone. The increase of band intensity changes of vasCH2,vsCH2 in the region 3000-2850cm-1 depended on aging, the disease progression and the dose of irradiation. The bands at 3080cm-1 and 1744cm-1, which originate from olefinic terminal bond (v=CH) and ester carbonyl group (vROCO), respectively, indicate the influence of oxidative stress on lipid degradation and peroxidation, respectively. The new bands at about 1690cm-1 and 1516cm-1 denote the presence of ß-sheet conformation of the proteins due to the diseases, confirming the increasing amount of lipophilic environment and fibril formation. Comparison of the FT-IR spectra of calcified aortic valve and hip heterotopic ossification with that of normal bones showed that in the bone-like formation the peroxide anion free radicals play an important role in the disease.

Performance and safety profile of regadenoson myocardial perfusion imaging: first experience in Greece.

OBJECTIVE: MPI can provide valuable information in the investigation of patients with known or suspected coronary artery disease. The stress component of the studies can be conducted with regadenoson, which was approved for clinical use in Greece in 2016. We investigated the performance and safety profile of regadenoson MPI based on our 7 months institutional experience. PATIENTS AND METHODS: We studied 96 consecutive patients (59 males, 37 females, mean age 70.35y.o, range: 46-87y.o.) referred to our department for a clinically indicated MPI study with pharmacological stress. Eleven patients suffered from chronic obstructive pulmonary disease. Patients underwent regadenoson stress test, combined with both stress and rest imaging. Data on the symptoms and electrocardiographic changes due to regadenoson administration were recorded. Symptoms were graded as 1-mild: a symptom that did not distress the patient, 2-moderate: a symptom that distressed the patient but it was self-limiting, or 3-severe: a symptom that distressed the patient requiring medical intervention. RESULTS: Regadenoson-related symptoms were reported in 56 patients and were: dyspnea, discomfort, dizziness, chest pain, epigastric pain, neck pain, headache, flushing, nausea, heartburn, weakness, and upper limbs numbness. The severity of symptoms was recorded as grade 1 in 30 patients, grade 2 in 25 patients, and grade 3 in 1 patient. Two or more different symptoms were reported in 28 patients. Ischemic electrocardiographic changes and arrhythmias were observed in 8 patients. CONCLUSION: Our findings support previously published data indicating the optimal safety profile of regadenoson MPI, even in the group of patients suffering from chronic obstructive pulmonary disease.

An infrared spectroscopic study of aortic valve. A possible mechanism of calcification and the role of magnesium salts.

In the present study fourier transform infrared (FT-IR) spectroscopy was used to study the mechanism of pathogenesis of aortic valve calcification. The high intensity bands of vCH3 and vCH2 groups of lipids and phospholipids of membranes, in the spectral region 3000-2800 cm(-1), show the high concentration of lipids and fatty components in aortic valve, resulting from degradation of the main aliphatic chain of the membranes, with a change of their permeability and fluidity. The presence of bands at 3075 and 1744 cm(-1), assigned to olefinic (v=CH) and aldehyde carbonyl groups, respectively, implies that reactive oxygen species are involved in the initiation of peroxidation of the lipids and phospholipids. These latter bands are related to the oxidative stress of the patients. From the shifts of bands to lower frequencies of the characteristic absorption bands of amide I and amide II, it is suggested that the proteins change their secondary structure from α-helix to ß-sheets and random coil due to modifications of collagen, associated with the permeability of aortic valve atherosclerosis. From the spectral region 1150-900 cm(-1), where the characteristic stretching vibration bands of the phosphate groups (vPO4(-3)) absorb, the calcified aortic valve was found to contain biological hydroxyapatite (Ca10(PO4)6(OH)2), as well as amorphous hydroxyapatite (Ca5(PO4)xOH) and CaHPO4. These findings are in agreement with scanning electron microscopy energy-dispersive X-ray analysis and X-ray diffraction analyses. SEM micrographs show that the valves are rich in fibrils and that the protein-protein cross-linked chemical bonds seem to be the points of initiation of calcification.

An unusual pattern of three major components of the cardiovascular system: multimodality imaging and review of the literature.

INTRODUCTION: Coronary artery anomalies are found in 0.4% to 1.4% of patients who undergo coronary angiography. Anomalous origin of left coronary artery from the right sinus of Valsava is the rarest, with a reported prevalence of 0.02 -0.03% according to angiographic studies. CASE PRESENTATION: We present the rare case of a 42-year-old-man suffering from stable angina with unusual development of 3 major components of the cardiovascular system Coronary angiography revealed an anomalous origin of the left coronary artery from the ostium of the right coronary artery. Magnetic resonance angiography depicted an anomalous origin of the left common carotid artery from the innominate artery and an aneurysm of descending thoracic aorta. Coronary computed tomography angiography revealed the course of left coronary artery between aortic root and conus arteriosus at the level of the right ventricular outflow tract. In this report we attempt to highlight the rarity of this vascular anatomy. CONCLUSION: Anomalous origins of the coronary arteries are rare, but may cause myocardial ischemia and sudden death. Thus, their reliable identification is a matter of paramount importance possibly evaluating the effects of therapeutic intervention. Newer imaging modalities improve the illumination of vascular system anatomy, shedding light to diagnostic dilemmas that come up in daily medical practice.

Oxidative stress and atherogenesis. An FT-IR spectroscopic study.

Atherosclerosis is a complex phenomenon which leads to sudden death. Fourier transform infrared (FT-IR) spectroscopy was used to study the pathogenic components of carotids that produce the atheromatic plaque at the molecular level, as well as the role of free radicals, which are developed during oxidative stress and their effect on plaque generation. The absorption infrared spectra reflected significant changes which were analogous to clinical data of each patient. The spectra contained signature bands of the biological molecules which were characteristic for the plaque components. The bands found at about 3080 cm(-1) and 1736 cm(-1) were proportional to low-density lipoprotein concentration for each patient, suggesting the hydroperoxidation of lipids due to free radicals, generated during oxidative stress. From scanning electron microscopy analysis, it was found that the carotid plaques contained calcium minerals, silicon and heavy metals, such as copper, silver, lead and titanium, which were related to the working environment of the patients.

Radial artery angioplasty after perforation during diagnostic cardiac catheterisation.

The use of the radial artery as an access site for diagnostic and interventional cardiac procedures has been extensively developed in recent years as a result of reduced complications at puncture site, reduced costs and the improvement in the patients' quality of life. The complications of trans-radial procedures are rarely major and very rarely life threatening--a key benefit of the radial approach. We describe the case of a patient who underwent percutaneous radial artery angioplasty, because of perforation caused during diagnostic cardiac catheterisation, in order to complete the catheterisation procedure before the patient proceeded to endovascular treatment of a sub-renal abdominal aortic aneurysm.