Material damage in TBCs by a synthetic CMAS and the non-destructive detection:-An exploration via a single crystal YSZ-

More recently a new type of damage has been pronounced in thermal barrier coatings (TBCs) by calcium-magnesium-alumino-silicates (CMAS) from ingestion of siliceous minerals under certain operating conditions, based on synthetic material in Table 1. In order to understand material aspect of CMAS damage, a study on material interaction between a synthetic CMAS and a single crystal yttria-stabilized zirconia (YSZ) was studied in this work. Here, the effect of crystallographic orientation on the interaction was also investigated. The experimental works clearly showed that the material interaction between the CMAS and YSZ was significant, resulting in the change in microstructural morphology(Fig. 1(a)). The extent of interaction depended on the crystallographic factor of the YSZ (Fig. 1(b)). The CMAS damage developed depending on the crystallographic plane of YSZ; it was the lowest onthe {111} plane.This is a noteworthy finding tomitigate the CMAS damagein EB-PVD top coat. The change in physical properties was also found to be pronounced at the CMAS damaged area. Based on these findings the non-destructive detection was also tried for engineering applications. Please click Additional Files below to see the full abstract

Material damage in TBCs by a synthetic CMAS and the non-destructive detection:-An exploration via a single crystal YSZ-

More recently a new type of damage has been pronounced in thermal barrier coatings (TBCs) by calcium-magnesium-alumino-silicates (CMAS) from ingestion of siliceous minerals under certain operating conditions, based on synthetic material in Table 1. In order to understand material aspect of CMAS damage, a study on material interaction between a synthetic CMAS and a single crystal yttria-stabilized zirconia (YSZ) was studied in this work. Here, the effect of crystallographic orientation on the interaction was also investigated. The experimental works clearly showed that the material interaction between the CMAS and YSZ was significant, resulting in the change in microstructural morphology(Fig. 1(a)). The extent of interaction depended on the crystallographic factor of the YSZ (Fig. 1(b)). The CMAS damage developed depending on the crystallographic plane of YSZ; it was the lowest onthe {111} plane.This is a noteworthy finding tomitigate the CMAS damagein EB-PVD top coat. The change in physical properties was also found to be pronounced at the CMAS damaged area. Based on these findings the non-destructive detection was also tried for engineering applications. Please click Additional Files below to see the full abstract

Left ventricular outflow tract obstruction with abnormal papillary muscles

AbstractA 65-year-old man with a history of hypertension was admitted to our hospital with fainting and syncope. He had experienced recurrent syncope since 20 years of age. On admission, systolic heart murmur was audible at the apex of the heart. Echocardiography revealed anteriorly displaced papillary muscles (PMs), elongation of the anterior mitral valve leaflet (AML), and systolic anterior motion (SAM) of the AML. Color Doppler imaging showed accelerated flow with a pressure gradient (PG) of 56mmHg at the left ventricular outflow tract (LVOT). Cardiac magnetic resonance imaging revealed mild asymmetric septal hypertrophy and multiple accessory PMs. Cine images clearly demonstrated SAM and LVOT obstruction due to anteriorly displaced PMs. Based on these findings, the patient was diagnosed as having hypertrophic cardiomyopathy and LVOT obstruction due to abnormal PMs. Oral administration of bisoprolol (2.5mg/day) was initiated, because the patient rejected surgical treatment. Follow-up echocardiography revealed a gradual decrease in the LVOT-PG to 24mmHg, and no episodes of fainting or syncope have recurred for 2 years after the initiation of bisoprolol.<Learning objective: Abnormal papillary muscle (PM) is an unusual cause of left ventricular outflow tract (LVOT) obstruction, and cardiac magnetic resonance (CMR) imaging has been reported to be useful for diagnosis of abnormal PM. Abnormal PMs with LVOT obstruction are usually treated by surgical correction, and therefore, reports on medical treatment are limited. We report a case of LVOT obstruction due to abnormal PMs, which was accurately diagnosed by CMR imaging and successfully treated with a beta-blocker.

Efficacy of Low-Density Lipoprotein Apheresis in Salvaging Critical Limb Ischemia Induced by Acute Thrombotic Occlusion on Peripheral Artery Disease

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Echocardiographic Manifestations in Patients with Cardiac Sarcoidosis

BackgroundCardiac sarcoidosis is a life-threatening disease with protean clinical manifestations, including congestive heart failure (CHF), conduction disturbance, ventricular arrhythmia and sudden death. Nonetheless, it is difficult to diagnose cardiac sarcoidosis in the clinical setting. Some echocardiographic findings of cardiac sarcoidosis associated with other diagnostic tools (201thallium scintigraphy, 67gallium citrate scan, serum markers and others) may be helpful upon early suspicion and diagnosis of cardiac sarcoidosis.Materials and MethodsFifty-two patients (36 female) with cardiac sarcoidosis, with a mean age of 48 ± 14 years (range, 21–70 yr), underwent a series of echocardiographic follow-up (mean, 88 ± 48 mo) examinations, and important echocardiographic parameters and findings were recorded.ResultsThere were left ventricular (LV) regional wall motion abnormalities (RWMAs) noted in 40 (localized in 16, multiple in 24), dilatation of the LV with impaired LV contractility in 28, thinning of the basal interventricular septum (IVS) in 27, thinning of LV free wall in 18, apical aneurysm in 12, apical thrombus in two, mimicking hypertrophic cardiomyopathy (HCM) in two, pericardial effusion (PE) in two (with cardiac tamponade in one), and LV wall thinning and aneurysm formation after steroid therapy for cardiac sarcoidosis in two of 43 patients.ConclusionThinning of the basal IVS or LV free wall is a specific echocardiographic finding of cardiac sarcoidosis. Other echocardiographic findings of cardiac sarcoidosis may mimic coronary artery disease (LV RWMA or apical aneurysm), CHF, or HCM. PE and thinning of the LV wall after steroid therapy were also noted in rare situations

Diagnostic utility of 123I-BMIPP imaging in patients with Takotsubo cardiomyopathy

Objective: Takotsubo cardiomyopathy is a cardiac syndrome with an acute onset defined by chest symptoms and ST segment elevation on electrocardiograms. Takotsubo cardiomyopathy is sometimes misdiagnosed as acute myocardial infarction (AMI). Therefore a non-invasive diagnostic method is needed to be established for setting up appropriate strategies. The purpose of this study was to detect myocardial metabolic abnormalities and to determine the diagnostic usefulness of 123I-beta-methy-iodophenyl pentadecanoic acid (123I-BMIPP) imaging in patients with takotsubo cardiomyopathy. Methods and results: We examined 16 patients with takotsubo cardiomyopathy and 12 with AMI in the left anterior descending artery. All patients were studied with resting 123I-BMIPP imaging. Total defect score (TDS) of 123I-BMIPP and perfusion were semi-quantitatively determined with single-photon emission computed tomography (SPECT) imaging using a 17-segment 5-point model. TDS of 123I-BMIPP were 4.8 ± 2.7 in patients with Takotsubo cardiomyopathy and 22.4 ± 10.7 in AMI. The ratio of summed BMIPP defect score of non-apical to apical segments in Takotsubo cardiomyopathy was smaller than that of the patients with AMI (0.1 ± 0.1 vs. 1.1 ± 0.7, p < 0.0001), indicating that 123I-BMIPP abnormalities were exclusively observed the in apical area. The ratio of summed perfusion defect scores of non-apical to apical segments in takotsubo cardiomyopathy did not differ significantly from that of AMI (0.52 ± 0.6 vs. 0.57 ± 0.3, p = NS). Summed BMIPP defect score in the apical area of takotsubo cardiomyopathy was larger than that of perfusion defect score (3.9 ± 2.7 vs. 1.8 ± 1.8, p = 0.04). Conclusion: Impaired metabolic metabolism exclusively in the apical region was observed by 123I-BMIPP SPECT images in takotsubo cardiomyopathy. These typical metabolic SPECT features of the disease can be utilized on differential diagnosis of takotsubo cardiomyopathy. © 2013.This is the author\u27s version of a work accepted for publication by Japanese College of Cardiology. Changes resulting from the publishing process, including peer review, editing, corrections, structural formatting and other quality control mechanisms, may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. The definitive version has been published in Journal of Cardiology, 64 (1), pp. 49-56,2014 July, 10.1016/j.jjcc.2013.10.01