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Aim To examine the impact of diabetes mellitus on procedural outcomes of patients who underwent percutaneous coronary intervention for chronic total occlusion. Methods We assessed the impact of diabetes mellitus on the outcomes of percutaneous coronary intervention for chronic total occlusion among 1308 people who underwent such procedures at 11 US centres between 2012 and 2015. Results The participants' mean ± sd age was 66 ± 10 years, 84% of the participants were men and 44.6% had diabetes. As compared with participants without diabetes, participants with diabetes were more likely to have undergone coronary artery bypass graft surgery (38 vs 31%; P = 0.006), and to have had previous heart failure (35 vs 22%; P = 0.0001) and peripheral arterial disease (19 vs 13%; P = 0.002). They also had a higher BMI (31 ± 6 kg/m2 vs 29 ± 6 kg/m2; P = 0.001), similar Japanese chronic total occlusion scores (2.6 ± 1.2 vs 2.5 ± 1.2; P = 0.82) and similar final successful crossing technique: antegrade wire escalation (46 vs 47%; P = 0.66), retrograde (30 vs 28%; P = 0.66) and antegrade dissection re-entry (24 vs 25%; P = 0.66). Technical (91 vs 90%; P = 0.80) and procedural (89 vs 89%; P = 0.93) success was similar in the two groups, as was the incidence of major adverse cardiac events (2.2 vs 2.5%; P = 0.61). Conclusions In a contemporary cohort of people undergoing percutaneous coronary intervention for chronic total occlusion, nearly one in two (45%) had diabetes mellitus. Procedural success and complication rates were similar in people with and without diabetes. [ABSTRACT FROM AUTHOR]

Seven large-scale high-strength concrete (HSC) shearwall specimens named HSCWI to HSCW7 were built and loaded to failure under inplane constant axial load and increasing horizontal loads. The test specimens were approximately 1/3 scale of a prototype wall. The compressive strength of concrete varied from approximately 11.6 ksi (80 Mzda) to more than 14.5 ksi (100 MPa) for different specimens. Except for Specimen HSCW4, which was tested imder a very high compressive stress of approximately -2.9 ksi (20 MPa), axial compressive stresses of approximately 1.2 ksi (8 MPa), 0.6 ksi (4 MPa), and zero were applied to the specimens. The horizontal reinforcement ratios of 0.47 and 0.75% and vertical reinforcement ratios of 0.75 and 1.26% were chosen for the wall panels. The experimental results of walls tested in this research as well as those reported by other researchers are compared with the ultimate resistance predicted by an interactive event simulator developed by the first author as well as the design procedures given in the Australian Standard AS3600 and AC1318. [ABSTRACT FROM AUTHOR]

The article presents a study on the design, properties and applications of low-calcium fly ash-based geopolymer concrete presented at the 31st International Conference on Advanced Ceramics and Composites. The study showed that low-calcium fly ash-based geopolymer concrete is suitable for structural applications because of its excellent compressive strength. Other properties of heat-cured low-calcium fly ash-based geopolymer concrete such as sulfate attack resistance are mentioned.

Reports on the development of fly ash-based geopolymer concrete. Efforts of the researchers to develop environmentally friendly construction materials; Contribution of ordinary portland cement production to greenhouse gas emission; Initiative aimed to reduce greenhouse gas emissions; Development of strategies to retain concrete as the material of choice for infrastructure and at the same time make it an environmentally friendly material.

Tests on half-sized models of edge panels of a flat plate floor are described. One model contained a spandrel beam and three did not. The purpose was to investigate the distribution of forces around an edge column. Measured slab moments and shears along the face of the spandrel showed what proportion of the total panel moment entered the column directly as bending and how much as torsion in the spandrel. The proportion of shear on each face was also deduced. Both the observed behavior and measured forces indicated that failure originated as a torsion-shear failure in the spandrel. Expressions are derived for the torsion and shear in the spandrel and also for the capacity of the spandrel to resist these. Emphasis is placed on adequate torsion steel in the spandrel to prevent what has hitherto been called a punching shear failure at an edge column. [ABSTRACT FROM AUTHOR]

Limitation of long-term deflections is an important consideration in the design of reinforced concrete flexural members. An expression is developed for maximum allowable span-depth ratios for reinforced concrete beams and one-way slabs. The derivations are based on Branson's deflection computation method recommended by ACI 318-77. Both the total deflection as well as the incremental deflection that may occur after attachment of nonstructural elements are limited. Finally, numerical examples are included to illustrate use of the proposed equations. [ABSTRACT FROM AUTHOR]

Three different methods of design for reinforced concrete horizontally curved beams are investigated. Tests were carried out on three beams designed by these methods. The beams were completely fixed at the supports and subjected to a vertical point load. The suitability of the design methods is discussed on the basis of observed behavior, strength, and modes of collapse, and by comparing the amount of steel required in each beam. [ABSTRACT FROM AUTHOR]

Tests on 22 prestressed concrete I-beams are re-ported. Most beams were tested in bending and torsion, but -four also carried shear. Seven beams had reinforcement linking the flanges to the webs, and fifteen had no such reinforcement. Strength theories are developed for both types of beams. It is concluded that flange reinforcement in I-beams is essential since without it the flanges add little to the strength of the web alone, and may even be detrimental. Building code rules should perhaps take account of this. [ABSTRACT FROM AUTHOR]

Results of torsion tests on ten rectangular rein-forced concrete beams are presented, the principal variables being aspect ratio and amount of rein-forcement. It is shown that, other things being constant, the strength decreases with an increase in aspect ratio. Equations are derived for ultimate torque and minimum reinforcement. Correlation between predicted and experimental strength is good, not only for the ten beams tested but for sixtyfour others available in the literature. [ABSTRACT FROM AUTHOR]

Limitation of long-term deflection is an important consideration in the design of flat plates and flat slabs. In this paper an expression is developed that relates the span-depth ratio of a slab to the relevant parameters. Since this expression is not suitable for design purposes, a parametric study was performed which permitted development of design equations. Correlation between predicted long-term deflection and the small amount of field data available is excellent. Comparison with two codes of practice indicates that the use of the minimum slab thicknesses specified by these codes can result in deflections which in many cases will be objectionable. Finally, the ease with which the prqposed equations can be used is illustrated in a design example. [ABSTRACT FROM AUTHOR]

An approximate method for the calculation of long-term deflections of flat plates and flat slabs !s described. The method is applied to compute deflections of three existing floors for which details are available. The agreement between measured and calculated deflections is good. [ABSTRACT FROM AUTHOR]

Equations developed in an earlier paper for the strength of prestressed beams subjected. to bending, torsion and shear are rearranged m a form suitable for design. A design example is included. [ABSTRACT FROM AUTHOR]

A simple expression for the calculation of final deflections of reinforced concrete flat slab and flat plate floors is proposed. The deflections calculated by the proposed expression agree closely with those measured in real buildings. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures are capable of significant redistribu-tion of internal forces between the uncracked state and maximum load. Results obtained from tests on large-scale models of edge panels of reinforced concrete flat plate floors subjected to uniformly dis-tributed vertical load are presented. Test results showed that between the uncracked condition and the maximum load there was a consid-erable redistribution of moments, the two support moments and the midspan moments varying by about 50 percent. This suggests that in the design process, any analysis involving a high degree of refine-ment is quite unnecessary and bears no relation to reality. The tests also indicated high moment intensity opposite the column face with a substantial drop in moment just beyond. Based on this study, simple rules for the design of reinforcement in edge panels of flat plate floors are proposed. [ABSTRACT FROM AUTHOR]

This paper presents the development of a theory for bonded prestressed concrete rectangular beams subjected to combined torsion, bending and shear. The analysis Is similar to the one proposed by Collins et al for reinforced concrete beams. Strength equations are derived for Mode 1, 2 and 3 failures. An empirical equation is developed for the case of shear-compression mode of failure. The predictions of the theory are compared with over one hundred test results available in the literature. In general the agreement is good. The strength was not over-estimated for any of the test beams. [ABSTRACT FROM AUTHOR]

Background: There is limited data on the impact of a second attending operator on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) outcomes., Methods: We analyzed the association between multiple operators (MOs) (>1 attending operator) and procedural outcomes of 9296 CTO PCIs performed between 2012 and 2021 at 37 centers., Results: CTO PCI was performed by a single operator (SO) in 85% of the cases and by MOs in 15%. Mean patient age was 64.4 ± 10 years and 81% were men. SO cases were more complex with higher Japan-CTO (2.38 ± 1.29 vs. 2.28 ± 1.20, p = 0.005) and Prospective Global Registry for the Study of Chronic Total Occlusion Intervention scores (1.13 ± 1.01 vs. 0.97 ± 0.93, p < 0.001) compared with MO cases. Procedural time (131 [87, 181] vs. 112 [72, 167] min, p < 0.001), fluoroscopy time (49 [31, 76] vs. 42 [25, 68] min, p < 0.001), air kerma radiation dose (2.32 vs. 2.10, p < 0.001), and contrast volume (230 vs. 210, p < 0.001) were higher in MO cases. Cases performed by MOs and SO had similar technical (86% vs. 86%, p = 0.9) and procedural success rates (84% vs. 85%, p = 0.7), as well as major adverse complication event rates (MACE 2.17% vs. 2.42%, p = 0.6). On multivariable analyses, MOs were not associated with higher technical success or lower MACE rates., Conclusion: In a contemporary, multicenter registry, 15% of CTO PCI cases were performed by multiple operators. Despite being more complex, SO cases had lower procedural and fluoroscopy times, and similar technical and procedural success and risk of complications compared with MO cases., (© 2023 Wiley Periodicals LLC.)

Objectives: To assess the feasibility and safety of same day discharge (SDD) after chronic total occlusion (CTO) percutaneous coronary intervention (PCI)., Background: CTO PCI has been associated with higher complication rates and procedural and hospitalization costs. Shortening post-PCI hospitalization length not only increases the patients' comfort but at the same time it consists an important part of cost reduction policies., Methods: We retrospectively compared the 30-day outcomes of patients who underwent CTO PCI at the Red Cross Hospital, Greece between January 2016 and June 2019 and underwent SDD versus non-SDD. Major adverse cardiovascular events (MACE) were defined as the composite of death, myocardial infarction, urgent repeat target vessel revascularization, tamponade, and stroke., Results: A total of 173 patients (mean age 63.7 ± 8.9 years) were included, of whom 51 (30%) underwent SDD. SDD patients were less likely to have diabetes mellitus (51 vs. 31%, p = .015), arterial hypertension (89 vs. 67%, p < .001), and acute coronary syndrome presentation (39.7 vs. 21.6%, p = .022), compared with non-SDD patients. Forearm access was used in all SDD patients and in 83% of the non-SDD patients. The 30-day incidence of MACE was 0% in the SDD group and 1.6% in the non-SDD group. Multivariable analysis showed that diabetes mellitus and longer procedural time were associated with lower probability of SDD (OR: 0.34, 95% CI: 0.15, 0.73 and OR: 0.29, 95% CI: 0.12, 0.71, respectively)., Conclusions: SDD appears to be feasible and safe in selected patients undergoing an uncomplicated CTO PCI through forearm approach., (© 2020 Wiley Periodicals LLC.)

Malignant fibrous histiocytoma (MFH)/undifferentiated pleomorphic sarcoma (UPS) is an uncommon malignancy in the head-and-neck region. UPS is a malignant neoplasm of uncertain origin that arises both in soft tissue and bone. We bring forth a 65-year-old female who presented with an ulceroproliferative growth in the right upper neck. Contrast-enhanced magnetic resonance imaging and 18 F-fluorodeoxyglucose positron emission tomography-computed tomography revealed a large exophytic, solid-cystic growth in the right parotid region with locoregional extension and few ipsilateral lymph nodes. Biopsy of the lesion revealed UPS, which was previously called MFH. She was considered for chemoradiotherapy. Correlative imaging helps in adequate staging of large tumors with assessment of response to chemoradiotherapy., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Indian Journal of Nuclear Medicine.)

Objectives: We sought to examine near-infrared spectroscopy (NIRS) imaging findings of aortocoronary saphenous vein grafts (SVGs)., Background: SVGs are prone to develop atherosclerosis similar to native coronary arteries. They have received little study using NIRS., Methods: We examined the clinical characteristics and imaging findings from 43 patients who underwent NIRS imaging of 45 SVGs at our institution between 2009 and 2016., Results: The mean patient age was 67 ± 7 years and 98% were men, with high prevalence of diabetes mellitus (56%), hypertension (95%), and dyslipidemia (95%). Mean SVG age was 7 ± 7 years, mean SVG lipid core burden index (LCBI) was 53 ± 60 and mean maxLCBI 4 mm was 194 ± 234. Twelve SVGs (27%) had lipid core plaques (2 yellow blocks on the block chemogram), with a higher prevalence in SVGs older than 5 years (46% vs. 5%, P = 0.002). Older SVG age was associated with higher LCBI (r = 0.480, P < 0.001) and higher maxLCBI 4 mm (r = 0.567, P < 0.001). On univariate analysis, greater annual total cholesterol exposure was associated with higher SVG LCBI (r = 0.30, P = 0.042) and annual LDL-cholesterol and triglyceride exposure were associated with higher SVG maxLCBI 4 mm (LDL-C: r = 0.41, P = 0.020; triglycerides: r = 0.36, P = 0.043). On multivariate analysis, the only independent predictor of SVG LCBI and maxLCBI 4mm was SVG age. SVG percutaneous coronary intervention was performed in 63% of the patients. An embolic protection device was used in 96% of SVG PCIs. Periprocedural myocardial infarction occurred in one patient., Conclusions: Older SVG age and greater lipid exposure are associated with higher SVG lipid burden. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Background: The Flash Ostial system (Ostial Corporation, Sunnyvale, CA) was designed to optimize implantation of aorto-ostial coronary stents by flaring the proximal stent struts against the aortic wall., Methods: We retrospectively reviewed the medical record, angiograms, and intravascular ultrasound images of 22 aorto-ostial percutaneous coronary interventions performed at our institution between March and September 2015. The Flash Ostial system was used in 13 cases (59%)., Results: Mean age was 67 ± 8 years and all patients were men. The target vessel was the right coronary artery (59%), left main (27%), or a saphenous vein graft (14%); 59% of the lesions had moderate/severe calcification. The mean number of predilation balloons was 1.8 ± 1.6, mean Flash ostial balloon diameter was 3.3 ± 0.5 mm and mean inflation pressure was 13.1 ± 4.0 atmospheres. Intravascular ultrasonography (available for 19 patients) revealed mean ostial minimum lumen cross-sectional area (MLA) of 9.2 ± 3.0 mm 2 and reference MLA of 8.5 ± 2.7 mm 2 . The percent difference between ostial and reference MLA was higher in cases in which the Flash Ostial system was used versus those where it was not (9.6 ± 5.5% vs. 4.0 ± 2.8%, P = 0.03). All stent struts were well apposed. Technical success was 100%. One patient developed a left groin pseudoaneurysm treated with thrombin injection and one patient had a periprocedural myocardial infarction. Median contrast, fluoroscopy time, and procedure time were 235 mL, 33 min, and 118 min, respectively., Conclusions: The Flash Ostial system can be successfully used in aorto-ostial stenting, resulting in large ostial vessel MLA. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Background: Daily radiation exposure over many years can adversely impact the health of medical professionals., Methods: Operator radiation exposure was recorded for 124 percutaneous coronary interventions (PCIs) performed at our institution between August 2011 and May 2013: 69 were chronic total occlusion (CTO)-PCIs and 55 were non-CTO PCIs. A disposable radiation protection sterile drape (Radpad; Worldwide Innovations & Technologies, Inc) was used in all CTO-PCI cases vs none of the non-CTO PCI cases. Operator radiation exposure was compared between CTO and non-CTO PCIs., Results: Mean age was 64.6 ± 6.2 years and 99.2% of the patients were men. Compared with non-CTO PCI, patients undergoing CTO-PCI were more likely to have congestive heart failure, to be current smokers, and to have longer lesions, and less likely to have prior PCI and a saphenous vein graft target lesion. CTO-PCI cases had longer procedural time (median: 123 minutes [IQR, 85-192 minutes] vs 27 minutes [IQR, 20-44 minutes]; P<.001), fluoroscopy time (35 minutes [IQR, 19-54 minutes] vs 8 minutes [IQR, 5-16 minutes]; P<.001), number of stents placed (2.4 ± 1.5 vs 1.7 ± 0.9; P<.001), and patient air kerma radiation exposure (3.92 Gray [IQR, 2.48-5.86 Gray] vs 1.22 Gray [IQR, 0.74-1.90 Gray]; P<.001), as well as dose area product (267 Gray•cm² [IQR, 163-4.25 Gray•cm²] vs 84 Gray•cm² [IQR, 48-138 Gray•cm²]; P<.001). In spite of higher patient radiation exposure, operator radiation exposure was similar between the two groups (20 μSv [IQR, 9.5-31 μSv] vs 15 μSv [IQR, 7-23 μSv]; P=.07)., Conclusions: Operator radiation exposure during CTO-PCI can be reduced to levels similar to less complicated cases with the use of a disposable sterile radiation protection shield.

Objectives: The Stenting of Saphenous Grafts-Xience V (SOS-Xience V) trial prospectively examined the frequency of angiographic in-stent restenosis in saphenous vein graft (SVG) lesions 12 months after implantation of a Xience V everolimus-eluting stent (EES; Abbott Vascular). Optical coherence tomography (OCT) during follow-up angiography was added to the protocol after OCT was approved for clinical use in the United States., Methods: Forty patients with 40 SVG lesions were enrolled in the study, of whom 27 underwent 12-month coronary angiography and 12 (only 1 of whom had in-stent restenosis) also had follow-up OCT evaluation. OCT strut-level analysis was performed to determine the percentage of strut coverage, malapposition, strut protrusion, neointimal thickness, and the existence of thrombus., Results: Mean patient age was 67 ± 7 years, and 95% were men. A total of 2584 struts were evaluated by OCT. The percentages for uncovered, malapposed, and protruding struts were 4%, 9%, and 15%, respectively. The mean strut neointimal thickness was 0.094 ± 0.094 mm. Of the 12 stents analyzed, 4 (33%) showed full neointimal coverage, 2 (17%) had all the struts embedded, 7 (58%) had at least 1 malapposed strut, and 10 (83%) had at least 1 protruding strut. The mean difference between the stent area and the lumen area was 0.36 ± 1.6 mm². No thrombus was detected in the stented areas., Conclusions: Use of EES in SVGs is associated with high rates of stent strut coverage and high malapposition rates at 12 months post implantation.