In-doped gallium oxide micro- and nanostructures: morphology, structure, and luminescence properties

The influence of indium doping on morphology, structural, and luminescence properties of gallium oxide micro- and nanostructures is reported. Indium-doped gallium oxide micro- and nanostructures have been grown by thermal oxidation of metallic gallium in the presence of indium oxide. The dominant morphologies are beltlike structures, which in many cases are twisted leading to springlike structures, showing that In diffusion in Ga2O3 influences the microstructure shapes. High-resolution transmission electron microscopy has revealed the presence of twins in the belts, and energy-dispersive X-ray spectroscopy in the scanning electron microscopy (SEM) has detected a segregation of indium impurities at the edges of planar structures. These results suggest that indium plays a major role in the observed morphologies and support the assumption of a layer by layer model as growth mechanism. An additional assessment of indium influence on the defect structure has been performed by cathodoluminescence in the SEM, X-ray photoelectron microscopy, and spatially resolved Raman spectroscopy

Temporal changes of left atrial function after orthotopic heart transplantation using cardiac magnetic resonance imaging in a single-center prospective study

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ÚNKP-19-3-I New National Excellence Program of the Ministry for Innovation and Technology; National Research, Development and Innovation Office of Hungary (NKFIA; NVKP_16-1-2016-0017 National Heart Program) Background The geometry and function of the left atrium (LA) change after orthotopic heart transplantation (HTX) with bicaval technique, as the LA has a recipient part around the pulmonary veins and a donor part, and these often contract separately. Because of this altered LA function, the recognition of left ventricular diastolic dysfunction can be challenging. The standard echocardiographic diastolic parameters are often in abnormal range in HTX patients despite of normal left ventricular diastolic function. Purpose The aim of our prospective study was to investigate the LA volumes and function and their temporal changes after HTX  using cardiac magnetic resonance (CMR). Method To better understand the cardiac characteristics of HTX patients, we started a prospective trial in January 2018. CMR was performed at one, three and six months after HTX. Left atrial contour detection was performed in 2- and 4-chamber views. Patients who had ≥Grade II allograft rejection before the CMR examination, were excluded (n = 6). In the remaining HTX patients (n = 37, 52 ± 12y, 29 male) and in a control group (n = 20, 49 ± 5y, 15 male) LA ejection fraction (EF), BSA-corrected maximum and minimum LA volume (Vi), stroke volume (SVi) were evaluated using bi-plane mode. LA global longitudinal strain (GLS) was defined with CMR based deformation imaging, called feature tracking. Results HTX patients had significantly higher LA volumes (maxLAVi 65 ± 22 vs. 46 ± 7 ml/m2, minLAVi 47 ± 21 vs. 18 ± 6 ml/m2) lower LASVi (19 ± 5 vs. 29 ± 4 ml/m2), LAEF (31 ± 10 vs. 62 ± 8%) and LA-GLS (10 ± 4 vs. 39 ± 11%) compared to the control group (p &amp;lt; 0.0001).  Analysing the temporal changes in HTX patients, we found an increase in the LA-GLS already at three months (10 ± 4 vs. 12 ± 3%, p &amp;lt; 0.05). The LAEF improved significantly at six months (29 ± 10 vs. 33 ± 10%, p &amp;lt; 0.05). Conclusion After HTX the LA volumes and function differ markedly from the normal population. The LA funcional parameters showed a moderate improvement after HTX. Better understanding the changes of left atrial function after HTX could help us to recognise  pathological conditions. Abstract Figure. Strain analysis of the left atrium </jats:sec

Structural and functional cardiac changes after transplantation: experiences of the first year of the prospective Heart-TIming CMR substudy

Abstract Background In case of heart transplantation (HTX) the heart is affected by several factors e.g. ischaemia/reperfusion, denervation, immunosuppression. During the adaptation, the heart may show marked temporal changes in terms of myocardial mechanics, function and tissue characteristics. To better understand cardiac temporal characteristics after orthotopic bicaval HTX we started the prospective Heart-TIming (Transplantation Imaging) trial in January 2018. Purpose In our CMR substudy we aimed to evaluate the physiological structural and functional left and right ventricular characteristics and their temporal changes after HTX using cardiac magnetic resonance. Methods As part of the study HTX patients underwent CMR at one, three, six and twelve months after HTX (n=49; 53±11y, 39 male). Cine images, T2-weighted, native T1 and T2 mapping, late gadolinium enhancement (LGE) and adenosine stress perfusion (at 1 and 12 month) images were acquired. In order to describe physiological characteristics of the transplanted heart we excluded pts with significant coronary artery disease, ischaemic scar, ≥Grade II allograft rejection from this present study (n=9). We evaluated the left (LV) and right ventricular (RV) ejection fractions (EF), volumes, masses (M) and the global LV strain values: longitudinal (GLS), circumferential (GCS) strain and the standard deviation (SD) of the peak longitudinal strain (LS) and the mechanical dispersion. In a basal short axis slice the native T1 and T2 mapping values were evaluated. We compared baseline CMR parameters to age and gender matched healthy controls (n=20; 48±10y, 16 male), and analyzed the temporal changes after HTX. Results Comparing the HTX patients' CMR parameters at one month with normal controls, HTX patients had lower end-diastolic volumes (LVEDVi: 74±15 vs 89±13 ml/m2; RVEDVi: 72±16 vs 89±15 ml/m2 p&amp;lt;0.05), stroke volumes (LVSVi: 45±7 vs 55±8 ml/m2, RVSVi: 43±8 vs 54±8 ml/m2, p&amp;lt;0.0001), higher LVMi (63±2 vs 55±3 g/m2, p&amp;lt;0.05), increased SD of peak LS (14±2 vs 10±2, p&amp;lt;0.0001) and more pronounced mechanical dispersion (18±5 vs 12±4, p&amp;lt;0.0001). The native T1 mapping values were significantly higher in HTX pts (1007±40 vs 975±24 ms, p&amp;lt;0,01). Examining temporal changes in HTX pts we found a decrease in LVMi (66±14 vs 59±10 g/m2, p&amp;lt;0.01) already at three months. At 12 months LVMi decreased further, less negative GLS (−25±4 vs −20±4, p&amp;lt;0.01) and GCS (−38±7 vs −34±4, p&amp;lt;0.05), and lower SD of the peak LS (14±2 vs 11±2, p&amp;lt;0.01) were measured. Conclusions Understanding the temporal changes of cardiac mechanics, function and tissue characteristics, furthermore the establishment of physiological values may help in the early, noninvasive identification of pathological changes in HTX pts. Tissue specific information in HTX pts Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Project no. NVKP_16-1-2016-0017 has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary, financed under the NVKP_16 funding scheme. Supported by the ÚNKP-18-3-IV New National Excellence Program of Human Capacities. </jats:sec

P1528The added value of cardiac magnetic resonance to the diagnosis of patients after aborted sudden cardiac death

Abstract Introduction An estimated 25% of all cardiovascular deaths are due to sudden cardiac death (SCD). The primary cause of SCD is coronary artery disease, however cardiac diseases accounted for SCD differ in young vs. older individuals. In patients with normal coronary angiography (NCA) the differential diagnosis is still challenging, due to the broad spectrum of underlying cardiovascular abnormalities. Cardiac magnetic resonance (CMR) provides accurate tissue specific and functional information of the heart. Purpose We aimed to investigate patients after aborted sudden cardiac death but NCA using cardiac magnetic resonance imaging (CMR). Our goal was to evaluate left and right ventricular parameters, presence of late gadolinium enhancement (LGE) and to assess the diagnostic value of CMR. Methods We enrolled 84 consecutive patients (39±13 y; 51% male) after aborted SCD with NCA and without CMR contraindication. CMR examination including long- and short-axis cine, T2-weighted and LGE images were performed. Left and right ventricular parameters were evaluated. Presence and pattern of the oedema and LGE were also assessed. Results Structural myocardial abnormality was present in 57% of pts: dilated (n=13), arrhythmogenic right ventricular (n=6) and hypertrophic (n=4) cardiomyopathy (CMP), moreover acute (n=2) and chronic (n=3) myocardial infarction, acute (n=2) and chronic (n=2) myocarditis, Tako-Tsubo CMP (n=1), noncompaction CMP (n=1), endomyocardial fibrosis (n=1). In 13 cases aspecific structural alterations were detected with (n=7) and without (n=6) LGE. Only 13% of the patients showed ejection fraction lower than 35% (LVEF=52±9%), 54% showed LV dilation (LVEDVi&gt;100 ml/m2 in males and &gt;90 ml/m2 in females; LVEDVi=104±22 ml/m2). LGE was present in 36%, showing ischemic pattern in five cases and nonischaemic pattern in 25 cases. Eleven patients were elite athletes (28±10y, 91% male, training hours: &gt;10 hours/week). Three of them showed ARVC based on the current Task Force criteria, another three athletes showed aspecific structural alteration with nonischaemic LGE. The CMR examination confirmed the referral diagnosis in 22%, excluded the presence of structural myocardial alteration in 43% and changed the clinical diagnosis in 35% of the patients. Conclusion CMR has an important diagnostic value in patients after reanimation but NCA. More than half of these patients showed structural alteration and CMR provided a diagnosis in 42%. Acknowledgement/Funding Project no. NVKP_16-1-2016-0017 has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary </jats:sec

P345 Temporal changes of left atrial function after orthotopic heart transplantation in a single-center prospective study

Abstract Funding Acknowledgements Project no. NVKP_16-1-2016-0017 has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary The geometry and function of the left atrium (LA) change after orthotopic heart transplantation (HTX) with bicaval technique, as the LA has a recipient part around the pulmonary veins and a donor part, and these often contract separately. Because of this altered LA function, the recognition of left ventricular diastolic dysfunction can be challenging. The standard echocardiographic diastolic parameters are often in abnormal range in HTX patients despite of normal left ventricular diastolic function. The aim of our prospective study was to investigate the LA volumes and function and their temporal changes after HTX using cardiac magnetic resonance (CMR). To better understand the cardiac characteristics of HTX patients, we started a prospective trial in January 2018. CMR was performed at one, three and six months after HTX. Left atrial contour detection was performed in 2- and 4-chamber views. Patients who had ≥Grade II allograft rejection before the CMR examination, were excluded (n = 2). In the remaining HTX patients (n = 21) and in a control group (n = 21) LA ejection fraction (EF), BSA-corrected maximum and minimum LA volume (Vi), stroke volume (SVi) were evaluated using bi-plane mode. LA global longitudinal strain (GLS) was defined with CMR based deformation imaging, called feature tracking. HTX patients had significantly higher LA volumes (maxLAVi 71 ± 22 vs. 47 ± 6 ml/m2, minLAVi 53 ± 22 vs. 18 ± 5 ml/m2) lower LASVi (19 ± 7 vs. 29 ± 4 ml/m2), LAEF (27 ± 10 vs. 62 ± 8%) and LA-GLS (8 ± 3 vs. 39 ± 10%) compared to the control group (p &amp;lt; 0.0001). Analysing the temporal changes in HTX patients, we found an increase in the LAEF (26 ± 8 vs. 30 ± 5%) and LA-GLS (8 ± 3 vs. 11 ± 3%) at three months (p &amp;lt; 0.05), there was no significant difference between the LA parameters at three and six months. Better understanding of the changes of left atrial function after HTX could help us to recognise pathological conditions. Abstract P345 Figure. Strain analysis of the left atrium </jats:sec

P3558Cardiac magnetic resonance characteristics of the transplanted heart: first results of the prospective Heart-TIming CMR substudy

Abstract Background In case of heart transplantation (HTX) the heart is affected by several factors e.g. ischaemia/reperfusion, denervation, immunosuppression. During the adaptation, the heart may show marked temporal changes in terms of myocardial mechanics, function and tissue characteristics. To better understand temporal characteristics after orthotopic bicaval HTX we started the prospective Heart-TIming (Transplantation Imaging) trial in January 2018 including standard 12-lead ECG, 24-hour Holter monitor, endomyocardial biopsy, transthoracic echocardiography, invasive coronary angiography with intravascular ultrasound and optical coherence tomography and cardiac magnetic resonance (CMR). Aim In our CMR substudy we aimed to evaluate the physiological structural and functional left and right ventricular characteristics and their temporal changes after HTX using CMR. Methods As part of the study HTX patients underwent CMR at 1, 3 and 6 months after HTX (n=31; 52±10.5y, 25 male). Cine images, T2-weighted, late gadolinium enhancement (LGE) and adenosine stress perfusion (at 1 month) images were acquired. In order to describe physiological characteristics of the transplanted heart we excluded pts with significant coronary artery disease, ischaemic scar, ≥Grade II allograft rejection from this present study (n=6). We assessed the left (LV) and right ventricular (RV) ejection fractions, volumes, masses (M) and LV strain. We assessed the global strain values: longitudinal, circumferential (GCS) strain and the standard deviation (SD) of the peak longitudinal strain (LS) and the left ventricular mechanical dispersion. We compared baseline volumetric and strain parameters to age matched healthy controls (n=20; 47±11.4y, 15 male), and the temporal changes between one, three and 6 months. Results Comparing the HTX patients' CMR parameters at one month with normal controls, HTX patients had lower LV and RV end-diastolic volumes (LVEDVi: 76.6±15.9 vs 90.6±11.6ml/m2; RVEDVi 74.5±17.5 vs 90.3±12.1ml/m2, p&lt;0.05),stroke volumes (p&lt;0.05) and higher LVMi (67.6±14.4 vs 57.2±11g/m2, p&lt;0.05). CMR based strain analysis of the HTX pts showed hyperkinetic GCS (−40,5±6.3% vs −35.2±4.8%, p&lt;0.05), increased SD of peak LS and more pronounced mechanical dispersion (p&lt;0.001) compared to the controls. Examining temporal changes in HTX pts we found a decrease in LVMi (69.57±16.4 vs 61.7±9.8g/m2, p&lt;0.05) already at three months, normalization of GCS (−37.7±5.5% vs −32.6±4.9%, p&lt;0.05) and decrease in SD of peak LS (13.5±2.3 vs 11.4±2.4, p&lt;0.05) at 6 months. Oedema was present in all pts at one month after HTX, and disappeared after three months. LGE with aspecific pattern was present in 42%. LGE with aspecific pattern in HTX pts Conclusions Understanding the temporal changes of LV mechanics, function and tissue characteristics, furthermore the establishment of physiological values may help in the early, noninvasive identification of pathological changes in HTX pts. NCT number: NCT03499197 Acknowledgement/Funding Project no. NVKP_16-1-2016-0017 has been implemented with the support provided from the National Research, Development and Innovation Fund of Hungary </jats:sec