Reversible Defects Research Articles

The relationship between fragmented QRS and mortality in without reversible defects patients with scintigraphical myocardial infarction diagnosis

Background/Aim: Evidence of increased mortality in perfusion abnormalities on myocardial perfusion scintigraphy (MPS) can be found. However, electrocardiography (ECG) is a cheaper and more easily accessible examination than MPS. Fragmented QRS (fQRS) is also considered to be associated with mortality in some cardiological diseases. The present study aimed to analyze the relationship between fQRS based on electrocardiography (ECG) and mortality in patients without reversible defects whose fixed hypoperfusion/perfusion defects were diagnosed and associated with myocardial infarction (MI) based on myocardial perfusion scintigraphy (MPS).
 Methods: Non-ischemic patients (2289 patients) with MI diagnoses based on scintigraphy were selected based on retrospective scintigraphy reports. The presence of fQRS was investigated in 85 patients whose 12-lead electrocardiographs could be accessed from the hospital archive, and their deaths due to all causes were questioned from the death information system. The relationship between left ventricular ejection fraction (LVEF), fQRS, type of exercise, number of leukocytes, other parameters, and mortality rates was analyzed.
 Results: The numbers of living (n = 69) and deceased (n = 16) patients were obtained. They were divided into two groups: (1) surviving patients (n = 69, number of fQRS positive 42) and (2) deceased (n = 16, number of fQRS positive 11). No distributional differences were found between mortality rates and fQRS and demographic features between groups (P = 0.558). However, a statistically significant effect was observed between mortality rates and low LVEF levels, pharmacological stress, number of leukocytes, and a low HDL level.
 Conclusion: The present study suggests that it may be useful to define benign features of fQRS. LVEF levels may be a very important parameter in decision-making for pharmacological stress, and its role in prediction of mortality may be higher than that obtained by fQRS.

The Relationship Between Coronary Dominance and Positive Results in Myocardial Perfusion Imaging.

ObjectiveOur study aims to evaluate the possible relationship between coronary artery dominance and its effect on accurately identifying reversible ischemia of inferior/inferior-lateral wall on cardiac perfusion imaging.BackgroundCoronary artery dominance is conventionally defined by the vessel which gives the rise to the AV nodal artery/posterior descending artery (PDA). Previous studies have explored the potential effect of coronary dominance on the accuracy of single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) tests in detecting inferior/inferior-lateral wall ischemia; further evidence is necessary to study that potential effect.MethodsWe conducted a single-center retrospective analysis to explore the potential relationship between coronary artery dominance and inferior/inferior-lateral wall ischemia on SPECT imaging. We identified a cohort of patients with a reversible defect(s) in the inferior and/or inferolateral walls on SPECT MPI who had subsequently undergone invasive coronary angiography. Coronary angiography was used to determine coronary dominance and to confirm the presence/absence of obstructive coronary artery disease in the distribution of the inferior and/or inferolateral wall(s). We correlated the findings on SPECT MPI to coronary angiography to identify true positives and false positive MPIs.ResultsA cohort of 200 patients was identified, patients in the cohort had undergone stress MPI with reversible defects with subsequent invasive coronary angiography. Baseline characteristics including age, BMI and sex were fairly well-balanced between the groups. The mean age was 68 +/- 11 in the right dominant group and 70 +/- 9 in the non right dominant group. One hundred and sixty-one patients (81%) were found to have right dominant circulation and 39 patients (19%) were found to have left or codominant circulation. Of the 161 patients in the right dominant group, 58 patients (36%) were found to have false positive stress MPI. Of the 39 patients in the left or codominant group, 23 patients (59%) were found to have false positive stress MPI. The incidence of false positive stress MPI in the inferior and inferolateral distribution is significantly higher in patients with non-right dominant coronary anatomy (p-value: 0.01).ConclusionNon-right coronary dominant anatomy could have high false positive MPI results in the inferior and inferolateral distribution. Therefore, the interpreting clinicians should exercise caution during the clinical evaluation of these patients.

Abstract 3157: KLF5 defines the secretory lineage and governs sphingolipid metabolism in the skin

Abstract Adult stem cells contribute to tissue regeneration and wound repair through cellular programs that can be hijacked by cancer cells. We previously reported such a phenomenon in skin, where squamous cell carcinomas adopt a plastic phenotype so called “stem cell lineage infidelity”, entailing a wide-spread co-expression of otherwise lineage restricted genes, exemplified by hair follicle factor SOX9 and interfollicular epidermal factor KLF5. Occurring transiently in wounds and persists in cancer, stem cell lineage infidelity is essential to drive wound repair and tumorigenesis. However, it remains unclear what were the functional mediators of lineage infidelity factors. We thus set out to investigate one of its defining factors, KLF5. Employing genome-wide transcriptome and epigenome profiling, we found KLF5 specifies the epidermal lineage in the skin and is essential for skin maturation in vivo. Strikingly, KLF5 binds to the genomic vicinity of, and transcriptionally controls, multiple key enzymes catalyzing rate-limiting steps of epidermal sphingolipid secretion, whose disruption led to loss of lipid ultrastructural integrity, compromised secretory machinery and selective decline of high complexity sphingolipids in the skin. Remarkably, lipid-rich dietary intervention was able to reverse skin defects caused by KLF5 ablation and KLF5 is prevalently disrupted in skin barrier and inflammatory diseases. Our findings suggest KLF5 serves as a master secretory lineage factor and a transcriptional governor of sphingolipid metabolism in the developing and diseased skin, warranting future investigation of its functional underpinning in wound repair and cancer. Citation Format: Yejing Ge. KLF5 defines the secretory lineage and governs sphingolipid metabolism in the skin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3157.

Myocardial perfusion imaging failed to improve patient risk classification compared with the revised cardiac risk index for early cardiac complications after major non-cardiac surgery.

Myocardial perfusion imaging (MPI) is frequently used for cardiac risk assessment before major non-cardiac surgery, but its ability to improve patient risk classification beyond simple clinical assessment is unknown. To explore the prognostic utility of MPI above a simple clinical risk calculator, the revised cardiac risk index (RCRI). A retrospective cohort study of at-risk patients who underwent MPI before major non-cardiac surgery in a tertiary hospital was conducted. Major adverse cardiac events (MACE) was defined as any myocardial infarction, acute pulmonary oedema, ventricular arrhythmia or cardiac death within 30 days of surgery. We analysed the predictive value of MPI for MACE using multivariable logistic regression and categorical net reclassification index. MACE occurred in 47 (7.4%) cases from 635 surgical procedures in 629 patients. MPI-identified medium or large-sized reversible perfusion defects (P = 0.02; odds ratio 2.9; 95% confidence interval 1.1-7.1) and RCRI score two or more (P = 0.03; odds ratio 2.3; 95% confidence interval 1.1-4.8) were significantly associated with MACE after adjusting for age, coronary revascularisation, surgical priority, need for general anaesthesia, left ventricular ejection fraction (LVEF) and fixed perfusion defects. MPI risk factors (LVEF, reversible perfusion and fixed perfusion defects) did not improve risk classification above baseline risk factors (age, RCRI and surgical priority). MPI risk factors are weak predictors for early cardiac complications after major non-cardiac surgery and failed to improve patient risk classification beyond essential assessment using age, RCRI and surgical priority. Clinicians should consider alternative risk assessment strategies because of MPI's poor prognostic utility and its associated time and financial costs.

Comparison of left ventricle mechanical dyssynchrony parameters in ischemic and non-ischemic patients using 13N-NH3 PET/CT

Background-AimThe relationship between perfusion pattern and stress-induced changes in Left Ventricular Mechanical Dyssynchrony (LVMD) has been previously described with controversial results using stress-rest perfusion imaging studies. The aim of this study was to assess the relationship between perfusion pattern and stress-induced changes in LVMD usingo regadenoson/rest13N-NH3 PET/CT. MethodsThere were 74 patients who underwent stress-rest 13N-NH PET/CT from January 2014 to October 2018 excluding patients with left bundle branch block, ventricular pacing and myocardial necrosis. The patients were divided into those with reversible perfusion defects at stress (Ischemic group, n = 18) and patients without reversible perfusion defects (non-ischemic group, n = 56). The LVMD parameters included: phase standard deviation (PSD) and phase histogram bandwidth (PHB), after stress and at rest. The ΔPSD (post-stressPSD-restPSD) and ΔPHB (post-stressPHB—restPHB) were calculated to measure stress-induced changes in LVMD. ResultsThere were no significant differences in LVMD parameters between post-stress and at rest in both groups. The PSD post-stress, ΔPSD and PHB post-stress were significantly higher in the ischemic group. ConclusionsUsing a vasodilator as a stress, the PSD and PHB post-stress and ΔPSD were significantly higher in the ischemic patients than the non-ischemic group, while there were no significant differences in each cohort between stress and rest indices.

Investigation of the Reverse Leakage Behavior and Substrate Defects in Vertical GaN Schottky and PIN Diodes

In this work, the effects of the substrate defect density and distribution on the reverse leakage behavior of GaN vertical Schottky diodes and p–i–n diodes are investigated. A direct connection between the reverse leakage behavior of GaN based vertical devices and the dislocation density of the underlying material was determined. The difference in the leakage current for devices on different locations of the wafer can be as high as 6 orders of magnitude (for p–i–n diodes) at −200V, for HVPE substrate with inhomogeneous but predictable defect distributions (GaN substrates with dot-core inversion domain features). For comparison, using HVPE substrates with uniform defect distribution (but with no cores), the p–i–n diodes show much more uniform leakage behavior, varying within only an order of magnitude, and that range fell within the much greater range of that for the inhomogeneous substrates. The substrates with inhomogeneous defect distribution proved to be useful to show the direct correlation. The topography measurements confirmed that the wafers with inhomogeneous defect distribution possess periodically patterned core-centers with higher defect density and larger lattice distortions surrounded by other regions, which have very low defect concentrations. Devices located away from the defective core-centers result in a reduction of the reverse bias leakage by over two orders of magnitude at −10 V for Schottky diodes. Similar trends are also observed in the p–i–n diodes; the devices close to the core centers show the highest reverse leakage (>0.01 A cm−2 at −200V). Devices further away from the core-centers (lower dislocation density) show lower reverse leakage current. Moreover, the p–i–n diodes on regions more than 300 μm away from the core-centers show the best leakage behavior (<10−7 A cm−2 at −200V) of all the devices, outperforming the devices on the substrates with uniform defect distribution (∼10−6 A cm−2 at −200V). The results from this study show that the substrate defect density and distribution play important roles in the device leakage current. X-ray topography is extremely effective for studying defect characteristics underneath individual devices. The use of the wafers with inhomogeneous, but predictable defect density clearly demonstrated the importance of low defect densities for high device performance.

Inpatient myocardial perfusion imaging characteristics of patients admitted with suspected type 2 myocardial infarction

Abstract Funding Acknowledgements Type of funding sources: None. Background ESC defines a type 1 myocardial infarction (T1MI) as "MI caused by atherosclerotic coronary artery disease and usually precipitated by atherosclerotic plaque disruption" and type 2 myocardial infarction (T2MI) as "ischaemic myocardial injury in the context of a mismatch between oxygen supply and demand". In practice it can be difficult to differentiate between MI types and the role of myocardial perfusion imaging (MPI) in making this distinction remains unclear. Purpose To establish whether suspected T2MI has different characteristics on MPI compared to suspected T1MI. Methods All inpatient MPI scans at our institution between 01/03/2018 and 28/02/2020 were retrospectively reviewed. Patients were excluded if they had a previous diagnosis of coronary artery disease, an invasive coronary angiogram prior to MPI, or a maximal troponin T &amp;lt; 14ng/l. Diagnoses were categorised based on review of scan request information. Echocardiography images were reviewed if within 30 days of MPI. Results 58 patients were included: 28 with suspected type 2 MI and 30 with suspected type 1 MI (mean age 70 vs. 75). There was no statistically significant difference in maximal troponin T between groups (T2MI 394.0 ng/l, T1MI 415.6 ng/l; p=0.90). 50% T2MI patients and 53% T1MI patients had a territorial defect on MPI (fully reversible defect 25% vs. 17%, partially reversible defect 7% vs. 33%, irreversible defect 14% vs. 3% for T2MI vs T1MI respectively). 25% T2MI patients had an area &amp;gt;10% LV myocardium volume showing reversibility, compared with 33% T1MI (p=0.49). Both groups had similar proportions of left ventricular (LV) impairment (both had 65% of patients with normal LV ejection fraction) and prevalence of regional wall motion abnormalities ((RWMA) 39% for T2MI, 35% for T1MI, p=0.76) on echocardiography. Conclusions A clinically significant proportion of the suspected T2MI group had territorial ischaemia. Additionally, both patient groups demonstrated similar proportion of patients with reversible ischaemia and of LV systolic dysfunction. Therefore differentiation between T2MI and T1MI can be challenging both clinically and with MPI. Prospective studies are required to establish the optimal methods for making the distinction between types of MI.

Risk Factors Associated With New-Onset Myocardial Perfusion Abnormalities in Kidney Transplant Candidates

The optimal coronary artery disease surveillance strategy for end-stage renal disease patients being evaluated for kidney transplantation is unknown. It is unclear what risk factors are associated with the development of new-onset perfusion abnormalities on serial myocardial perfusion imaging. Potential kidney transplant recipients who underwent 2 myocardial perfusion imaging studies at Emory University Hospital between January 2010 and December 2019 were identified. We assessed the frequency of development of any new perfusion defect and development of moderate to severe ischemia (reversible perfusion defect >10%) on serial imaging. Finally, we identified the clinical and imaging factors associated with new perfusion defects and explored the association between new perfusion defects and all-cause mortality. History of myocardial infarction (MI) and peripheral artery disease was associated with an increased risk of developing a new perfusion defect. History of MI was also associated with the risk of developing moderate-severe ischemia. Female patients were less likely to develop new perfusion defects or moderate-severe ischemia. There was no association between either outcome and all-cause mortality. In conclusion, a history of MI, peripheral artery disease, and male gender are risk factors for developing new perfusion defects, although only the history of MI and male gender predict moderate to severe ischemia. Interval development of any abnormal perfusion is not associated with increased mortality.

Fragmented QRS complex as a marker of myocardial fibrosis in patients with coronary artery disease

Aim– to analyze the relationship between fQRS and myocardial fibrosis in CAD patients using SPECT.&#x0D; Material and methods.Retrospectively, we have analyzed the anamnesis and examinations of 116 patients with suspected coronary heart disease. The fQRS was assessed according to the criteria of Das M. et al., 2006, along with the presence of a pathological Q wave and a slow increase in the amplitude of the R wave. We analysed the transient myocardial ischemia and/or myocardial scarring using stress/rest SPECT with technetium-99m.&#x0D; Results.fQRS was significantly more frequently detected in patients with stable and partially reversible perfusion defects – 44.1% and 52.2%, respectively, versus 13.0% and 5.5% in patients without perfusion defects or with reversible perfusion defects, p 0.05. Among 28 patients with QRS fragmentation and myocardial fibrosis, 19 (67.8%) had classical signs of fibrosis on the ECG, 9 (32.1%) had no ECG-registered fibrosis but fQRS was detected. The sensitivity of fQRS marker in detecting myocardial fibrosis reached 84.4%, the specificity was 63.3%.&#x0D; Conclusion.fQRS complex is an informative marker for detecting myocardial scarring in patients with coronary artery disease. Analysis of fQRS in daily clinical practice may increase the diagnostic value of electrocardiography in the detection of fibrosis.

Inferior myocardial wall ischemia on SPECT-MPI in patients with non dominant right coronary artery and non significant coronary artery disease

BackgroundThe impact of a non-dominant right coronary artery (NDRCA), on single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI)has not been clarified. Methods and resultsWe compared SPECT-MPI results of consecutive patients without significant (diameter stenosis ≥50%)coronary artery disease (CAD) and a NDRCA (Group-1), with those of patients from our database without CAD and a dominant RCA (Group-2). All patients were subjected to SPECT-MPI with I.V. infusion of adenosine, and TC99-tetrofosmin. Group-1 included 69 patients (55 men, 79.7%), mean age 66.8 ± 9.8 years. Group-2 consisted of 79 patients (56 men, 70.9%), mean age 62.7 ± 11.5. There was no difference in demographics and CAD risk factors between the two groups. The SPECT-MPI revealed inferior wall ischemia, in 35 patients (50.7%), in Group-1 and 27 patients (34.1%), in Group-2 (P = 0.041). ConclusionsA relatively high rate of reversible SPECT-MPI perfusion defects may be anticipated in patients with an unobstructed NDRCA compared to patients with a dominant RCA.

Anti-Oxidative and Anti-Inflammatory Micelles: Break the Dry Eye Vicious Cycle.

Dry eye disease (DED) impacts ≈30% of the world's population and causes serious ocular discomfort and even visual impairment. Inflammation is one core cause of the DED vicious cycle, a multifactorial deterioration in DED process. However, there are also reactive oxygen species (ROS) regulating inflammation and other points in the cycle from the upstream, leading to treatment failure of current therapies merely targeting inflammation. Accordingly, the authors develop micelle‐based eye drops (more specifically p38 mitogen‐activated protein kinases (MAPK) inhibitor Losmapimod (Los)‐loaded and ROS scavenger Tempo (Tem)‐conjugated cationic polypeptide micelles, designated as MTem/Los) for safe and efficient DED management. Cationic MTem/Los improve ocular retention of conjugated water‐soluble Tem and loaded water‐insoluble Los via electrostatic interaction with negatively charged mucin on the cornea, enabling an increase in therapeutic efficiency and a decrease in dosing frequency. Mechanistically, MTem/Los effectively decrease ROS over‐production, reduce the expression of proinflammatory cytokines and chemokines, restrain macrophage proinflammatory phenotypic transformation, and inhibit cell apoptosis. Therapeutically, the dual‐functional MTem/Los suppress the inflammatory response, reverse corneal epithelial defect, save goblet cell dysfunction, and recover tear secretion, thus breaking the vicious cycle and alleviating the DED. Moreover, MTem/Los exhibit excellent biocompatibility and tolerability for potential application as a simple and rapid treatment of oxidative stress‐ and inflammation‐induced disorders, including DED.

Highlights From the Circulation Family of Journals

Highlights From the <i>Circulation</i> Family of Journals

Three-dimensional Fusion of Myocardial Perfusion SPECT and Invasive Coronary Angiography Guides Coronary Revascularization

BackgroundSPECT myocardial perfusion imaging (SPECT MPI) and invasive coronary angiography (ICA) provide complementary clinical information in the diagnosis of coronary artery disease (CAD). We have developed an approach for 3D fusion of perfusion data from SPECT MPI and coronary anatomy from ICA. In this study, we aimed to evaluate its clinical value when compared to the traditional side-by-side readings. MethodsThirty-six CAD patients who had at least one stenosis ≥ 50% were retrospectively enrolled. Based on the presence of a perfusion defect in a territory subtended by a coronary vessel, all vessels were classified as matched, unmatched, or normal groups via both the fusion and side-by-side analysis. The treatments recommended by the fusion and side-by-side analysis were compared with those that the patients received. Major adverse cardiac events (MACE), defined as all-cause death, myocardial infarction, unstable angina requiring hospitalization, and unplanned revascularization, were assessed. ResultsThe overall vessel-based concordance was 78.7% between the fusion and side-by-side analysis. Compared with the side-by-side analysis, 23 coronary arteries (29 equivocal segments) of 19 patients were reclassified via fusion of data. In the matched, unmatched, and normal groups, the numbers of vessels with hemodynamically significant stenosis which caused reversible defect were 37 vs 53, 28 vs 14, and 43 vs 41 (P < .01) when comparing the side-by-side analysis with the fusion, and the revascularization ratios per vessel were 69% vs 88%, 29% vs 10%, and 2% vs 2% between them. During the five-year follow-up, 8 patients (22.2%) experienced MACE. Patients who received the same treatment as the guidance of 3D fusion results (n = 22) had superior outcomes when compared with those who did not (n = 14) (P < .01). ConclusionsCompared with the side-by-side analysis, the 3D fusion of SPECT MPI and ICA provided incremental diagnostic and prognostic value.

Strain-tuning of domain walls in multilayer graphene probed in the quantum Hall regime

Domain walls, topological defects that define the frontier between regions of different stacking in multilayer graphene, have proved to host exciting physics. The ability of tuning these topological defects in-situ in an electronic transport experiment brings a wealth of possibilities in terms of fundamental understanding of domain walls as well as for electronic applications. Here, we demonstrate through a MEMS (micro-electromechanical system) actuator and magnetoresistance measurements the effect of domain walls in multilayer graphene quantum Hall effect. Reversible and controlled uniaxial strain triggers these topological defects, manifested as new quantum Hall effect plateaus as well as a discrete and reversible modulation of the current across the device. Our findings are supported by theoretical calculations and constitute the first indication of the in-situ tuning of topological defects in multilayer graphene probed through electronic transport, opening the way to the use of reversible topological defects in electronic applications.

Relationship Between Myocardial Perfusion Imaging Abnormalities on Positron Emission Tomography and Anginal Symptoms, Functional Status, and Quality of Life.

Myocardial perfusion imaging (MPI) identifies abnormalities that occur early in the ischemic cascade leading to angina. Our aim was to study the association between ischemic measures on positron emission tomography MPI and patients' health status; their symptoms, function, and quality of life. Health status was collected using the Seattle Angina Questionnaire (SAQ-7, 0-100, higher=better) and Rose Dyspnea Score (RDS) on 1515 outpatients with known or suspected coronary artery disease presenting for clinically indicated pharmacological 82Rb positron emission tomography MPI from July 2018 to July 2019. Adjusted multivariable ordinal regression models were used to assess the association between MPI findings of ischemia and the SAQ physical limitation, angina frequency, quality of life, summary score, and the RDS. The mean SAQ and RDS scores of the cohort (mean age 71.7 years, 55% male, 37.6% prior myocardial infarction or revascularization) were 73.8±28.6 (physical limitation), 87.4±21.7 (angina frequency), 79.0±26.1 (quality of life), 81.3±19.0 (summary score), and 2±2 (RDS). No perfusion, flow or function abnormalities were significantly associated with SAQ angina frequency scores. Low left ventricular ejection fraction reserve (≤0%), low global and regional myocardial blood flow reserve (<2) were independently associated with worse SAQ Physical Limitation score, SAQ summary score, and RDS (30% to 57% greater odds; all P≤0.01), but reversible perfusion defects were not. Impaired augmentation of left ventricular ejection fraction and myocardial blood flow with stress is associated with significant angina-associated functional limitation, health status, and dyspnea in patients who underwent positron emission tomography MPI, but not the frequency of their angina. Future studies should evaluate whether therapies that improve stress-induced abnormalities in systolic function and myocardial flow may improve patients' health status.

Effect of Runner Distance on Microstructure and Properties of Semi-Solid Squeeze Casting CuSn10P1 Alloy

It is easy to form reverse segregation and shrinkage porosity defects during the solidification of CuSn10P1 alloy, which leads to the poor properties and limits its application in high strength and toughness parts. In this paper, semi-solid CuSn10P1 alloy slurry was prepared by enclosed cooling slope channel (for short ECSC). The effect of runner distance on microstructure and properties by liquid squeeze casting and semi-solid squeeze casting was studied. The results showed that the microstructure of semi-solid squeeze casting is finer than that of liquid squeeze casting, and the shrinkage defects are improved. The solid fraction with 65 mm runner is lower than that without runner in liquid squeeze casting and semi-solid squeeze casting due to the retention effect of solid phase in semi-solid slurry flow, but the properties with 65 mm runner is better than that without runner. The ultimate tensile strength, yield strength and elongation of semi-solid squeeze casting CuSn10P1 alloy with 65 mm runner distance reached 466.5 MPa, 273.6 MPa and 13.4%, which were improved by 26%, 19% and 97%, respectively, as compared to that of liquid squeeze casting.

COVID-19 Geçiren Pulmoner Sekeli Olmayan Hastalarda Kalıcı Dispne Nedeni Kardiyak Tutulumdur: Retrospektif Çalışma

Objective: Several forms of cardiovascular involvement have been described in acute coronavirus disease-2019 (COVID-19) infection and also it has been shown that acute infection is responsible for cardiac symptoms. However, the data on cardiac involvement and associated symptoms in chronic phase remains unclear. Recent evidence have shown that the reason for persistent dyspnea can be persistent cardiac dysfunction in post COVID-19 infection. The aim of our study was to investigate the relationship between persistent dyspnea and cardiac involvement in post COVID19 patients without pulmonary sequelae. Material and Methods: In our study, we recruited 30 post COVID-19 patients with dyspnea between January 2021 and July 2021. In all patients, the absence of pulmonary sequelae was detected with PFT and chest- CT. 2D-TTE, 2DSTE and MPS were performed for each case. Results: Left ventricular dysfunction was detected in 63.3% of patients and also 93.3% of patients had extensive abnormal GLS at 3 month follow-up. Of the patients, 33.3% had myocardial perfusion defect (MPD) and all MPDs were observed to be reversible defects. MPD was obviously seen in anterior wall (60%) and mid (20%) to apical (70%) segments. As compared with patients without MPD, patients with MPD had higher CK-MB (p: 0.016) and troponin I (p: 0.011), lesser PW thickness (p:0.020) and lower peak systolic strain rate at A2C view (p:0.031). Patients with NYHA III had more impaired GLS than patients with NYHA II (p:0.035). Conclusion: Our study suggests ischemic or nonischemic cardiac dysfunction may be associated with persistent dyspnea in post- COVID- 19 patients without lung sequelae.

New optical method to study oxygen activity in flowing liquid

The necessity to study the oxygen activity of aqueous media in the flowing state to solve various problems has been substantiated. It has been found that emitted γ-quanta as a result of decay of 16N nuclei with energy more than 9 MeV cause the formation of additional color centers and reversible optical defects in the fiber. Their appearance leads to increased radiation-induced losses in the optical fiber, which reduce the power of laser radiation transmitted through it. A new optical method has been developed that makes it possible to study the nature of oxygen activity change by the number of γ-quanta emitted by 16N nuclei when the liquid moves along the pipeline. For the first time, the nature of the change in the spectral distribution of the number of 16N nuclei emitted as a result of oxygen activity was investigated, and its features in the current flow were determined. In order to realize long-term studies of oxygen activity, a method was proposed to restore optical properties of fiber in the presence of background radioactive radiation. Keywords:

Myocardial Perfusion Imaging Failed to Improve Patient Risk Classification Compared to the Revised Cardiac Risk Index for Early Cardiac Complications After Major Non-Cardiac Surgery

Cardiac evaluation is desirable before major non-cardiac surgery with myocardial perfusion imaging (MPI) frequently utilised for risk assessment. However, the prognostic utility of MPI above a simple clinical risk calculator, the Revised Cardiac Risk Index (RCRI), is unknown. We conducted a retrospective cohort study of patients who underwent MPI before major non-cardiac surgery, incorporating 635 surgical procedures in 629 patients over six years. Major adverse cardiac events (MACE) within 30 days of surgery, including any myocardial infarction, acute pulmonary oedema, ventricular arrhythmia, or cardiac death, occurred in 47 (7.4%) cases. We analysed predictive value of MPI for MACE using multivariable logistic regression and categorical net reclassification index. MPI-identified medium or large-sized reversible perfusion defects (p=0.02, odds ratio 2.9 [95% CI 1.1-7.1]) and RCRI score two or more (p=0.03, odds ratio 2.3 [(95% CI 1.1-4.8]) were significantly associated with MACE after adjusting for age, coronary revascularisation, surgical acuity, need for general anaesthesia, left ventricular ejection fraction (LVEF) and fixed perfusion defects. Net reclassification index comparing models with and without MPI risk factors (LVEF, reversible perfusion and fixed perfusion defects) did not significantly improve risk classification. MPI risk factors are weak predictors for early cardiac complications after major non-cardiac surgery and failed to improve patient risk classification beyond a simple risk assessment using age, RCRI and surgical priority. Clinicians should consider alternative risk assessment strategies because of MPI's poor prognostic utility and its associated time and financial costs.

Orbital Apex Syndrome With Encephalitis: A Rare and Serious Complication of Herpes Zoster Ophthalmicus

Introduction: Herpes zoster reactivation is more common in the elderly population. Although ocular complications are seen in 20-70% of patients with herpes zoster ophthalmicus, orbital apex syndrome is a rare case. Encephalitis is also a rare neurologic complication of HZO. Purpose: To report a Herpes Zoster Ophthalmicus (HZO)case with rare neurologic complication that ophthalmologist should be aware of. Case Presentation: A 68-year-old man had a chief complaint of a sudden blurred vision in right eye two days before admission, followed by rash and pain on the right upper eyelid and forehead. Visual acuity was hand movement on the right eye and 0.5 on the left eye. The patient had total ophthalmoplegia and total ptosis on his right eye, reverse relative afferent pupillary defect on his left eye and right peripheral facial nerve palsy. Optic discs were found to be normal on both eyes. The patient was diagnosed as orbital apex syndrome on his right eye associated HZO and right peripheral facial nerve palsy. The patient received oral acyclovir 800 mg five times/day and intravenous methylprednisolone 250 mg four times/day for three days. After four days of admission, the patient had a seizure and loss of his consciousness. The patient was consulted to neurology department and was given anticonvulsant therapy. The spinal tap revealed pleocytosis and increased protein. The patient was diagnosed as herpes zoster encephalitis. After one week, the patient regained full consciousness and his visual acuity was improved to 0.16 on the right eye. Color vision, visual field, and contrast sensitivity were also improved, ophthalmoplegia were partially resolved and peripheral facial nerve palsy was fully resolved. Conclusion: Herpes Zoster Ophthalmicus affect the central and peripheral nervous system at the same time and can be life-threatening with delayed diagnosis and treatment. It may be necessary to collaborate with the neurology department for every HZO case to minimize the life-threatening complications of HZO.