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Objectives: Comparison of coronary artery stent assessment with cardiac CT angiography (cCTA) using traditional filtered back projection (FBP) and sinogram affirmed iterative reconstruction (SAFIRE), in both full- and half-radiation dose image data.Methods: Dual-source cCTA studies of 37 implanted stents were reconstructed at full- and half-radiation dose with FBP and SAFIRE. Half-dose data were based on projections from one DSCT detector. In-stent noise, signal-to-noise ratio (SNR), and stent-lumen attenuation increase ratio (SAIR) were measured and image quality graded. Stent volumes were measured to gauge severity of beam hardening artefacts.Results: Full-dose SAFIRE reconstructions were superior to full-dose FBP vis-à-vis in-stent noise (21.2 ± 6.6 vs. 35.7 ± 17.5; P < 0.05), SNR (22.1 ± 8.6 vs. 14.3 ± 6.7; P < 0.05), SAIR (19.6 ± 17.6 vs. 33.4 ± 20.4%; P < 0.05), and image quality (4.2 ± 0.86 vs. 3.5 ± 1.0; P < 0.05). Stent volumes were lower measured with SAFIRE (119.9 ± 53.7 vs. 129.8 ± 65.0 mm(3); P > 0.05). Comparing half-dose SAFIRE with full-dose FBP, in-stent noise (26.7 ± 13.0 vs. 35.7 ± 17.5; P < 0.05) and SNR (18.2 ± 6.9 vs. 14.3 ± 6.7; P < 0.05) improved significantly. SAIR (31.6 ± 24.3 vs. 33.4 ± 20.4%; P > 0.05), stent volume (129.6 ± 57.3 vs. 129.8 ± 65.0 mm(3); P > 0.05), and image quality (3.5 ± 1.0 vs. 3.7 ± 1.1; P > 0.05) did not differ. Radiation dose decreased from 8.7 ± 5.2 to 4.3 ± 2.6 mSv.Conclusions: Iterative reconstruction significantly improves imaging of coronary artery stents by CT compared with FBP, even with half-radiation-dose data. [ABSTRACT FROM AUTHOR]

(1) In 1981 and 1982 male and female reproductive success of mainland and near- and distant-island populations of Centrosema virginianum and Opuntia stricta growing on two island and one mainland beach communities on the western coast of Florida were compared. (2) Pollen dispersal to neighbouring plants (which was used as an estimate of male reproductive success) was significantly reduced in both island populations of Centrosema relative to the mainland population. Pollen dispersal of Opuntia was significantly lower at the far island than at the near island. (3) Female reproductive success (estimated by fruit set) was significantly lower in Centrosema on the distant island than on the near island or mainland during 1981. Fruit set in Opuntia did not differ between the near and far island however, seeds per fruit were significantly lower on the far island both years. (4) Field experiments indicated significant pollinator limitation of fruit set for Centrosema growing on the far island in 1981, but not in 1982. On the far island in 1983, there was no significant difference in the number of seeds per fruit in naturally-pollinated and hand-crossed Opuntia flowers. (5) The differences between island and mainland pollinator communities and reproductive success that were found in plant communities separated by less than 10 km of water, suggest that pollinator limitation may be an important selective force on plant communities of distant, oceanic islands. [ABSTRACT FROM AUTHOR]

The decomposition of Malachite Green, CI Basic Green 4, by carbon arc light source has been studied in aqueous solution and on sulfoethyl and carboxymethyl ethers of cellulose. A mechanism for the photochemical decomposition has been proposed for both the solution and cellulose substrates. The decomposition products isolated from the aqueous solution studies included benzaphenone, 4-methylaminobenzophenone, 4-dimethylaminobenzophenone and p-dimethylaminophenol. Evidence for the formation of both ketones was also found in cellulose substrate reaction products. Chromatographic, infrared and mass spectra analyses were used to identify the decomposition products. The fact that the decomposition products were similar from both the solution and fiber substrate studies is taken as evidence for an analogous decomposition mechanism leading to their formation. The pKa of the anionic dye site on the fiber substrate directly influenced the fading rate of Malachite Green. [ABSTRACT FROM AUTHOR]

Can a Sports Ministry program positively impact the church's mission among its members? Previous research with commitment theory in psychology as it relates to sports and religious activity (2, 19) indicates that what benefits that church members get out of attending church activities will impact their frequency of attendance and commitment to their church. Sports activities have long been used as a tool to bring people into the church and increase fellowship and evangelism (11). To date, there has been little empirical research into the specific benefits of a sports ministry in the opinion of the church leaders who have sports activities in their church. [ABSTRACT FROM AUTHOR]

Despite impressive improvements in the care of patients with ST-segment elevation myocardial infarction, mortality remains high. Reperfusion is necessary for myocardial salvage, but the abrupt return of flow sets off a cascade of injurious processes that can lead to further necrosis. This has been termed myocardial ischemia-reperfusion injury and is the subject of this review. The pathologic and molecular bases for myocardial ischemia-reperfusion injury are increasingly understood and include injury from reactive oxygen species, inflammation, calcium overload, endothelial dysfunction, and impaired microvascular flow. A variety of pharmacologic strategies have been developed that have worked well in preclinical models and some have shown promise in the clinical setting. In addition, there are newer mechanical approaches including mechanical unloading of the heart prior to reperfusion that are in current clinical trials., Competing Interests: Funding Support and Author Disclosures Dr Welt has served as a consultant to Xenter Inc and Faraday Pharmaceuticals. Dr Drakos has served as a consultant to Abbott Laboratories; and has received research support from Novartis. Dr Kapur has received consulting/speaker fees from Abbott, Abiomed, Boston Scientific, Edwards, Getinge, LivaNova, Teleflex, and Zoll; and has received institutional research grants from Abbott, Abiomed, Boston Scientific, Getinge, LivaNova, and Teleflex. All other authors have reported that they have no relationships relevant to contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. All rights reserved.)

Background: Hand fractures are among the most common injuries presenting in pediatric emergency departments (EDs) with incidence reported as high as 624 hand fractures per 100,000 person-years. If gone untreated, these injuries can lead to pain, loss of function, and psychological trauma. The purpose of this study was to identify risk factors and characterize pediatric hand fractures over a 5-year period., Methods: The National Electronic Injury Surveillance System (NEISS) was queried for all hand fractures in patients aged 1 to 19 years presenting to US EDs between 2016 and 2020. Incidence was calculated using US census data. Cases were retrospectively analyzed using age, location of the injury, sex, coronavirus disease-2019 (COVID-19) era, and etiology of injury. Bivariate logistic regression was used where appropriate., Results: A total of 21,031 pediatric hand fractures were identified, representing an estimated 565,833 pediatric hand fractures presenting to EDs between 2016 and 2020. The mean incidence of pediatric hand fractures was 138.3 fractures for 100,000 person-years [95% confidence interval (CI): 136.2-140.4], with a 39.2% decrease in incidence occurring between 2019 and 2020. It was found that 42.2% of the fractures were in patients aged 10 to 14. The incidence of hand fractures for males and females was 97.9 (95% CI: 96.2-99.7) and 40.4 (95% CI: 39.2-41.5), respectively, with the male rate peaking at age 14 and the female rate peaking at age 12. Age, sex, location of the injury, and injury during the COVID-19 pandemic were demonstrated to influence the frequency and etiology of the fracture., Conclusion: This study determined the incidence of pediatric hand fractures presenting to EDs across the United States. In addition, it identified risk factors for common hand fracture etiologies (sports-related, falling, crush, punching) and demonstrated the change in rates of different etiologies of pediatric hand fractures that presented to US EDs during the COVID-19 pandemic., Level of Evidence: Level III-retrospective comparative study., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Despite the fact that door-to-balloon times have been greatly reduced, the rates of death and the incidence of heart failure in patients with ST-segment elevation myocardial infarction (MI) have plateaued. There is still an unmet need to further reduce MI size in the reperfusion era. Most adjunctive therapies to enhance myocardial salvage have failed, but some have shown promise. Currently, the only adjunctive therapy in a pivotal trial that has demonstrated reductions in infarct size is localized delivery of supersaturated oxygen (SSO 2 ) therapy. This review provides background on prior infarct size reduction efforts. The authors describe the preclinical data that shows the effectiveness of SSO 2  in reducing MI size, improving regional myocardial blood flow and cardiac function, and reducing adverse left ventricular remodeling-presumably by reducing patchy areas of residual ischemia within the reperfused risk zone. Potential mechanisms by which SSO 2 is beneficial are described, including the delivery of high levels of dissolved oxygen through plasma to ischemic, but viable, vascular and myocardial cells, thus allowing their survival and function. The authors then describe the SSO 2 clinical trials, demonstrating that in patients with anterior ST-segment elevation MI, SSO 2 therapy safely and effectively reduces infarct size, improves cardiac function, and reduces adverse left ventricular remodeling., Competing Interests: Drs Kloner and Burkhoff have been consultants for ZOLL TherOx. Dr Creech is an employee of ZOLL TherOx. Drs. Stone and O’Neill have been consultants for ZOLL TherOx; and were involved in previous clinical trials with SSO2. Dr Spears was involved with preclinical studies with SSO2., (© 2021 The Authors.)

Purpose: Quadriceps tendon (QT) autograft ACL reconstruction was hypothesized to possess less anterior knee laxity, pivot shift laxity, and lower failure rates than hamstring tendon (HT) autografts., Methods: Terms "hamstring tendon autograft" and "ACL reconstruction" or "quadriceps tendon autograft" and "ACL reconstruction" were searched in Embase and PubMed. Inclusion criteria required that studies included patients treated for primary ACL injury with reconstruction using either a QT autograft (Group 1) or a HT autograft (Group 2) and instrumented anterior knee laxity assessment. Extracted information included surgical fixation method, graft type, graft thickness or diameter, single vs. double bundle surgical method, publication year, time between the index knee injury and surgery, % women, initial and final subject number, subject age, follow-up length, side-to-side anterior knee laxity difference, Lysholm Score, Subjective IKDC score, anterior knee laxity side-to-side difference grade, ipsilateral pivot shift laxity grade, and failure rate. The Methodological Index for Nonrandomized Studies was used to evaluate study methodological quality., Results: The QT group (Group 1) had 17 studies and the HT group (Group 2) had 61 studies. Overall, Group 2 had greater pivot shift laxity (OR 1.29, 95% CI 1.05-1.59, p = 0.005). Group 2 suspensory femoral fixation had greater pivot shift laxity (OR 1.26, 95% CI 1.01-1.58, p = 0.02) than Group 1 compression femoral fixation. Group 2 compression femoral fixation also had more anterior knee laxity (OR 1.25, 95% CI 1.03-1.52, p = 0.01) than Group 1 compression femoral fixation and higher failure rates based on initial (OR 1.69, 95% CI 1.18-2.4, p = 0.002) and final (OR 1.89, 95% CI 1.32-2.71, p = 0.0003) subject number. Failure rate for HT compression femoral fixation was greater than suspensory femoral fixation based on initial (OR 2.08, 95% CI 1.52-2.84, p < 0.0001) and final (OR 2.26, 95% CI 1.63-3.16, p < 0.0001) subject number., Conclusions: Overall, QT autografts had less pivot shift laxity and lower failure rates based on final subject number than HT autografts. Compression QT autograft femoral fixation had lower pivot shift laxity than suspensory HT autograft femoral fixation. Compression QT autograft femoral fixation had less anterior knee laxity and lower failure rates than compression HT autograft femoral fixation. Suspensory HT autograft femoral fixation had lower failure rates than compression HT autograft femoral fixation. Greater knee laxity and failure rates may be related to a combination of HT autograft diameter and configuration (tissue quality and dimensions, strands, bundles, and suturing method) variability and fixation mode., Level of Evidence: Level IV.

Background: The use of cementless femoral components has become the standard in younger patients due to increased implant survivorship and decreased loosening. However, it remains controversial whether these femoral stems can provide comparable results in elderly patients. Therefore, our purpose was to compare the (1) incidence of revisions; (2) clinical outcomes; (3) incidence of postoperative blood transfusions; and (4) differences in complications between the 2 cohorts., Methods: Seventy-four consecutive patients (78 hips) aged 80 years or older, who underwent primary total hip arthroplasty using a cementless, tapered, femoral stem were retrospectively compared with a matched cohort of 76 patients (78 hips) who were less than 80 years. Mean age was 83 years (range, 80-91 years) vs 59 years (range, 17-79 years) for the matched group. Minimum follow-up was 2 years. Revision rates, clinical outcomes using the Harris Hip Score, incidences of complications, and postoperative transfusion rates were evaluated., Results: In the octogenarian cohort, the aseptic survivorship was 99%, compared with 95% in the matched group. There were 2 aseptic loosenings (2.6%): 1 femoral implant loosening (1.3%) and 1 acetabular loosening, but only 1 revision was performed, as one of the patients declined revision surgery. In the matched cohort, there were 6 revisions (7.7%). There were no significant differences in revision rates between the 2 cohorts, and no significant differences in final Harris Hip Score scores. The incidence of blood transfusion in the study group was 42% vs 19% in control group (P < .01)., Conclusion: The use of cementless, tapered, femoral stems yielded excellent results in the octogenarian group, although adequate patient preoperative optimization is necessary given the significantly higher transfusion incidence., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The purpose of this study was to determine whether the use of a periarticular injection using liposomal bupivacaine could decrease pain and improve outcomes after total knee arthroplasty. Fifty consecutive patients received no periarticular injections (group A). Another 50 consecutive patients received a periarticular injection of liposomal bupivacaine (group B). There were no differences in the groups with respect to gender, age, body mass index (BMI), or comorbidities. There was a significant reduction in the amount of narcotics used in the liposomal bupivacaine group (60.97-mg oral morphine equivalent vs 89.74 mg, P  = 0.009). Patients in group B with a BMI <40 and a Charlson comorbidity index of 0-3 had decreased length of stay (2.64 vs 3.06 days, P  = .004), narcotic use over 24-48 hours (110.66 vs 182.47 mg, P  = .013), and narcotic use over 48-72 hours (49.61 vs. 112.65 mg, P  = .004). In patients with a BMI <40 and comorbidity index of ≤3, periarticular injection using liposomal bupivacaine leads to earlier discharge along with decreased use of narcotics.

The tunable swelling and rolling of films assembled via layer-by-layer (LbL) methods from poly(N-isopropylacrylamide-co-acrylic acid) (pNIPAm-co-AAc) microgels and poly(ethylenimine) (PEI) have been systematically studied. Microgel/PEI films assembled at pH 7.4 display a high degree of in-plane swelling at low pH that dramatically increases the film area and drives self-delamination from the substrate to form a free-standing film. The degree of film swelling can be controlled by the size of microgels used in film fabrication. Taking advantage of this feature, self-rolled scrolls can be easily obtained from microgel/PEI films prepared from microgels of two different sizes. The rolling direction can be controlled by the assembly of different size microgels in different film strata, and the final shape of the scrolls can be controlled by scratching the desired film edges. The present work contributes to a deeper understanding of microgel/PEI film swelling properties and introduces a facile and novel method to prepare free-standing films and self-rolled scrolls.

Multilayer coatings made from hydrogel microparticles (microgels) are conceptually very simple materials: thin films composed of microgel building blocks held together by polyelectrolyte "glue". However, the apparent simplicity of their fabrication and structure belies extremely complex properties, including those of "dynamic" coatings that display rapid self-healing behavior in the presence of solvent. This contribution covers our work with these materials and highlights some of the key findings regarding damage mechanisms, healing processes, film structure/composition, and how the variation of fabrication parameters can impact self-healing behavior.

Unlabelled: Transient ischemic dilation (TID) in the setting of abnormal stress-rest cardiac SPECT myocardial perfusion imaging (MPI) has been linked with increased cardiovascular risk. However, the significance of TID in the setting of an otherwise normal SPECT MPI study has not been clearly established. In this study, cardiac CT was used to evaluate the prevalence of atherosclerotic lesions and the severity of coronary artery stenosis in patients with TID of the left ventricle with or without associated myocardial perfusion defects on SPECT MPI., Methods: The study population consisted of 1,553 consecutive patients who had undergone both cardiac CT and SPECT MPI within 1 mo between January 1, 2006, and September 1, 2011. Patients included in the study group had a pathologic TID value defined as ≥1.18 for men and ≥1.22 for women. Coronary CT angiography was used to evaluate each coronary segment for the presence and composition of atherosclerotic plaque and the degree of coronary stenosis. TID-positive patients were compared with a 2:1 risk-factor-matched-pair control cohort without TID., Results: TID was identified in 30 patients who were compared with TID-negative risk-factor-matched controls (n = 60). When compared with the TID-negative control cohort, TID-positive patients had no significant differences in the presence and extent of atherosclerosis, the degree of coronary artery stenosis, or the calcium score at cardiac CT. Similarly, there were no significant differences in these CT measures in TID-positive patients with a normal perfusion study (n = 20) when compared with TID-negative patients with a normal perfusion study (n = 48). In addition, there was no significant difference in the incidence of major adverse cardiac events when comparing both the TID-positive patients and the TID-negative control cohort and when comparing patients who were TID-positive with normal perfusion with patients who were TID-negative with normal perfusion., Conclusion: The presence of TID with an otherwise normal SPECT MPI study does not translate into a greater extent of coronary artery disease as assessed by cardiac CT or increased risk for future major adverse cardiac events., (© 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Rationale and Objectives: To investigate the impact of iterative reconstruction in image space (IRIS) on image noise, image quality (IQ), and postprocessing at coronary computed tomography angiography (cCTA) compared to traditional filtered back-projection (FBP)., Materials and Methods: The cCTA results of 50 patients (26 men; 58 ± 15 years, body mass index 31.5 ± 6.7 kg/m²) were investigated using a second-generation dual-source computed tomography system. Scan data were reconstructed with the use of IRIS and FBP algorithms. Two radiologists independently evaluated the reconstructions using automated coronary tree analysis software. Image noise was measured and IQ was rated on a 5-point Likert scale. The number of manual corrections after automated vessel segmentation, the time required to complete segmentation, and the number of missed segments were assessed in both IRIS and FBP reconstructions. Results were compared using paired t-test., Results: IRIS significantly reduced image noise compared to FBP (23.3 ± 8.8 vs. 33.5 ± 13.5 Hounsfield units, P < .001). Subjective IQ improved with IRIS (IRIS 3.2 ± 1.0 vs. FBP 3.0 ± 1.0, P < .05). IRIS decreased the time needed for coronary segmentation from 111.9 ± 40.5 seconds to 95.2 ± 38.2 seconds with FBP (P < .01) and required fewer manual corrections (5.7 ± 3.0 vs. 6.8 ± 3.6, P < .01). The number of missed vessel segments was not significantly different (3.6 ± 1.8 vs. 3.8 ± 1.9, P > .05) between IRIS and FBP, respectively., Conclusions: During cCTA postprocessing, IRIS significantly decreases the time and the number of manual corrections for a complete coronary segmentation compared to FBP. This effect is likely attributable to suppression of image noise by IRIS, which improves the performance of automated vessel segmentation and positively impacts cCTA analysis., (Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.)

Microgel multi-layer films assembled from anionic particles and linear polycation were prepared on elastomeric substrates and their self-healing properties studied. Dried films were imaged in situ during mechanical deformation and were determined to undergo plastic deformation in response to linear strain, leading to film buckling upon strain relaxation. Hydration leads to rapid reorganization of the film building blocks, permitting recovery of the film to the undamaged state. Additionally, films were determined to heal in the presence of high relative humidity environments, suggesting that film swelling and hydration is a major factor in the restoration of film integrity, and that full immersion in solvent is not required for healing. Films prepared from microgels with lower levels of acid content and/or polycation length, factors strongly connected to the charge density and presumably the connectivity of the film, also display self-healing characteristics.

Objectives: To evaluate image quality (IQ) of low-radiation-dose paediatric cardiovascular CT angiography (CTA), comparing iterative reconstruction in image space (IRIS) and sinogram-affirmed iterative reconstruction (SAFIRE) with filtered back-projection (FBP) and estimate the potential for further dose reductions., Methods: Forty neonates and children underwent low radiation CTA with or without ECG synchronisation. Data were reconstructed with FBP, IRIS and SAFIRE. For ECG-synchronised studies, half-dose image acquisitions were simulated. Signal noise was measured and IQ graded. Effective dose (ED) was estimated., Results: Mean absolute and relative image noise with IRIS and full-dose SAFIRE was lower than with FBP (P < 0.001), while SNR and CNR were higher (P < 0.001). Image noise was also lower and SNR and CNR higher in half-dose SAFIRE studies compared with full-and half-dose FBP studies (P < 0.001). IQ scores were higher for IRIS, full-dose SAFIRE and half-dose SAFIRE than for full-dose FBP and higher for half-dose SAFIRE than for half-dose FBP (P < 0.05). Median weight-specific ED was 0.3 mSv without and 1.36 mSv with ECG synchronisation. The estimated ED of half-dose SAFIRE studies was 0.68 mSv., Conclusions: IR improves image noise, SNR, CNR and subjective IQ compared with FBP in low-radiation-dose paediatric CTA and allows further dose reductions without compromising diagnostic IQ., Key Points: • Iterative reconstruction techniques significantly improve non-invasive cardiovascular CT in children. • Using half traditional radiation dose image quality is higher with iterative reconstruction. • Iterative reconstruction techniques may allow further radiation reductions in paediatric cardiovascular CT.

Objectives: Performance evaluation of a fully automated system for calculating computed tomography (CT) coronary artery calcium scores from contrast medium-enhanced coronary CT angiography (cCTA) studies., Methods: One hundred and twenty-seven patients (58 ± 11 years, 71 men) who had undergone cCTA as well as an unenhanced CT calcium scoring study where included. Calcium scores were computed from cCTA by an automated image processing algorithm and compared with calcium scores obtained by standard manual assessment of unenhanced CT calcium scoring studies. Results were compared vis-a-vis (1) absolute calcium score values, (2) age-, gender- and race-dependent percentiles, and (3) commonly used calcium score risk classification categories., Results: One hundred and nineteen out of 127 (93.7%) studies were successfully processed. Mean Agatston calcium score values obtained by traditional non-contrast CT calcium scoring studies and derived from contrast medium-enhanced cCTA did not significantly differ (235.6 ± 430.5 vs 262.0 ± 499.5; P > 0.05). Calcium score risk categories and Multi-Ethnic Study of Atherosclerosis (MESA) percentiles showed very high correlation (Spearman rank correlation coefficient = 0.97, P < 0.0001/0.95, P < 0.0001) between the two approaches., Conclusions: Calcium score values automatically computed from cCTA are highly correlated with standard unenhanced CT calcium scoring studies. These results suggest a radiation dose- and time-saving potential when deriving calcium scores from cCTA studies without a preceding unenhanced CT calcium scoring study.

Objective: The objective of our study was to evaluate radiation dose and quantitative image quality parameters at high-pitch CT angiography (CTA) of the aorta compared with conventional CTA., Materials and Methods: We studied the examinations of 110 patients (65 men and 45 women; mean age ± SD, 64 ± 15 years) who had undergone CTA of the entire aorta on a second-generation dual-source CT system; 50 examinations were performed in high-pitch mode. The mean arterial attenuation, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) were calculated for the high-pitch CTA and conventional CTA groups. Radiation exposures were compared., Results: All studies were considered of diagnostic quality. At high-pitch CTA, the mean tube voltage and tube current-exposure time product were 118 ± 7 kV (SD) and 197 ± 78 mAs compared with 120 ± 1 kV and 258 ± 78 mAs, respectively, at conventional CTA (p < 0.05). The mean volume CT dose index, dose-length product, and effective dose were 8.1 ± 2.4 mGy, 561.1 ± 178.6 mGy × cm, and 9.6 ± 3.0 mSv at high-pitch CTA and 18.3 ± 7.7 mGy, 1162.6 ± 480.1 mGy × cm, and 19.8 ± 8.2 mSv at conventional CTA (p < 0.001). Attenuation was similar for both protocols, whereas significantly less contrast medium was injected for high-pitch CTA than for standard-pitch CTA (87.3 ± 16 mL vs 97.9 ± 16 mL, respectively; p < 0.01). The SNR and CNR were significantly lower in the high-pitch CTA examinations (p < 0.01), whereas the FOM was nonsignificantly higher. Twenty patients underwent both high-pitch CTA and conventional CTA, with a 45% reduction in radiation dose (p < 0.001)., Conclusion: High-pitch CTA of the aorta yields 45-50% reduction of radiation exposure as well as contrast medium savings with maintained vessel attenuation.

Background: The performance of dual-energy CT (DECT) for the detection of myocardial blood volume deficits has not systematically been compared with single-energy CT (SCT) spectra., Objective: We evaluated the accuracy for detection of myocardial blood volume deficits in DECT and SCT compared with 99m-Tc-Sestamibi-SPECT (single-photon emission CT) during rest and stress., Methods: 47 patients underwent rest/stress SPECT myocardial perfusion imaging and cardiac DECT on a dual-source CT scanner. The A- and B-tubes were operated with 140 kV and 80 kV/100 kV, respectively. DECT raw data were reconstructed by (1) only using high-energy (140 kV) CT spectra, (2) only using low-energy (80 kV/100 kV) CT spectra, (3) merging data (30% low- and 70% high-energy CT spectra), and (4) DECT-based iodine maps. Two independent, blinded observers analyzed all CT data according to each of the 4 reconstruction strategies for myocardial blood volume deficits., Results: Specificity and positive predictive values were relatively similar between the 4 reconstruction strategies, with highest specificity (98%) of SCT datasets based on 140 kV for mixed perfusion deficits seen on SPECT. DECT iodine maps showed highest sensitivity, negative predictive value, and accuracy of 91%, 97%, and 93%, respectively, for mixed perfusion deficits. Analysis with receiver operating characteristics showed highest area under the curve values (0.84-0.93) with the use of DECT iodine maps in the detection of purely fixed and mixed perfusion deficits., Conclusion: DECT iodine maps show superior performance for the detection of fixed and mixed perfusion deficits compared with SCT spectra., (Copyright © 2011 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.)

The use of coronary computed tomography angiography (cCTA) is growing rapidly, in large part because of fast-paced technical innovations that have increased diagnostic accuracy while providing new opportunities for radiation dose reduction. cCTA using recent generation CT scanners has been repeatedly shown to have excellent negative predictive value for ruling out significant coronary stenosis in comparison with invasive coronary angiography (ICA) and is now accepted for this use in selected populations. Current work is increasingly focused on evaluating and optimising radiation dose reduction techniques, the cost-effectiveness of cCTA implementation, and the impact of cCTA on patient management and outcomes. In addition, the potential value of emerging applications, such as atherosclerotic plaque characterisation and myocardial perfusion and viability assessment, are undergoing intense investigation., (© 2011 Blackwell Publishing Ltd.)

Objectives: This study sought to determine whether hyperoxemic reperfusion with aqueous oxygen (AO) improves recovery of ventricular function after percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI)., Background: Hyperbaric oxygen reduces myocardial injury and improves ventricular function when administered during ischemia-reperfusion., Methods: In a prospective, multicenter study, 269 patients with acute anterior or large inferior AMI undergoing primary or rescue PCI (<24 h from symptom onset) were randomly assigned after successful PCI to receive hyperoxemic reperfusion (treatment group) or normoxemic blood autoreperfusion (control group). Hyperoxemic reperfusion was performed for 90 min using intracoronary AO. The primary end points were final infarct size at 14 days, ST-segment resolution, and delta regional wall motion score index of the infarct zone at 3 months., Results: At 30 days, the incidence of major adverse cardiac events was similar between the control and AO groups (5.2% vs. 6.7%, p = 0.62). There was no significant difference in the incidence of the primary end points between the study groups. In post-hoc analysis, anterior AMI patients reperfused <6 h who were treated with AO had a greater improvement in regional wall motion (delta wall motion score index = 0.54 in control group vs. 0.75 in AO group, p = 0.03), smaller infarct size (23% of left ventricle in control group vs. 9% of left ventricle in AO group, p = 0.04), and improved ST-segment resolution compared with normoxemic controls., Conclusions: Intracoronary hyperoxemic reperfusion was safe and well tolerated after PCI for AMI, but did not improve regional wall motion, ST-segment resolution, or final infarct size. A possible treatment effect was observed in anterior AMI patients reperfused <6 h of symptom onset.

Background: Intracoronary aqueous oxygen (AO) hyperoxemic perfusion, initiated shortly (15-30 min) after the onset of postinfarction reperfusion, reduces infarct size and improves left ventricular function. Whether such therapy provides similar benefits when administered many hours after the onset of reperfusion is unknown. Accordingly, the hypothesis was tested that AO hyperbaric perfusion, performed 24 h after the onset of postinfarction reperfusion, reduces infarct size and improves left ventricular ejection fraction (LVEF) in swine., Methods: Following a 1-h balloon occlusion of the left anterior descending coronary artery in air-ventilated juvenile domestic swine, reperfusion was allowed to proceed without adjunctive therapy overnight in all animals. The following day, half of the reanesthetized, air-ventilated swine were randomized to treatment with intracoronary AO hyperbaric perfusion for 90 min (n=6, mean arterial perfusate PO(2)=899+/-78 mm Hg), while the remainder served as controls (n=6)., Results: Infarct size by triphenyl tetrazolium chloride was reduced by 48% and the [area of necrosis]/[area at risk] ratio was reduced by 44% in the AO group compared to the control group (p<0.05). By serial ventriculography, mean LVEF improved by 21% during AO perfusion, relative to baseline and control group values (p<0.05), with no significant change 1 h after completion of treatment (p>0.05)., Conclusion: AO hyperbaric perfusion, delayed 24 h after the onset of postinfarction reperfusion, reduces infarct size and improves LVEF in an experimental animal model.

Previous studies have demonstrated that the metastability threshold of aqueous oxygen (AO) is inversely dependent on the internal diameter of capillary tubes used to deliver it into blood. The hypothesis was tested herein that significantly higher thresholds are attainable with capillaries having markedly smaller dimensions (submicron) than those previously studied. Water was equilibrated with oxygen over a 0.3- to 0.7-k bar range. Inert gases (argon, helium) facilitated studies at pressures to 2.5 k bar. An argon-ion laser was used to visualize fluorescein in the liquid effluent from silica capillaries that were tapered at the distal end to a submicron internal diameter (0.5 +/- 0.3 microns). During infusion of the fluorescent effluent into host water at 21 degrees C and atmospheric pressure, integrity of the effluent and lack of microbubbles were monitored by videomicroscopy. No microbubbles were noted at AO concentrations ranging from 7.5 to 12.8 ml O2/g (0.34 to 0.68 k bar, respectively) or in the aqueous argon effluent at concentrations to 14 ml Ar/g (0.75 k bar). For aqueous helium, effluent nucleation was not observed at a mean concentration of 13 +/- 3 ml He/g (2.0 +/- 0.5 k bar), with an upper value of 15.2 ml He/g (2.4 k bar). The data represent the highest values of the tensile strength of water ever observed and approximate its theoretical homogeneous nucleation limit. Thus, remarkably high metastable concentrations of AO and other gases are attainable with the use of submicron capillaries.

We report a case of recurrent myocardial infarction occurring in two different coronary territories in a man with HIV-1 infection. On each occasion, clinical and angiographic success was obtained by intracoronary stent placement.

A patient underwent laser balloon angioplasty (LBA) combined with local intracoronary heparin therapy for treatment of a high grade stenosis of the mid-portion of the left anterior descending (LAD) coronary artery. Sustained patency of the LBA-treated lesion and no new coronary stenoses were found in a 10-year angiographic follow-up study., ((J Interven Cardiol 2005;18:357-360).)

Melanomas of sporadic and familial origin develop in a stepwise fashion in approximately 40-80% of all cases; yet, the genetic events governing the progression from nevocytic precursor lesions to early and advanced-stage melanomas remain largely unknown. In the present study, we provide an analysis of genes that were identified in four recently generated primary and metastatic melanoma Serial Analysis of Gene Expression (SAGE) libraries. In addition to SAGE tags corresponding to transcripts with unknown function, or to unidentified transcripts, known genes were identified that hitherto have not been shown to be expressed or have a function in early and advanced-stage melanomas and/or melanoma precursor lesions. Conducting fluorescence imaging analysis with cyanine dye-conjugated antibodies and oligonucleotides, we established the expression pattern of ATM, HEI10, PKD1, KAI11, IL-10R, and hypothetical protein FLJ11151 in nevus and melanoma specimens.

Uncorrected microvascular ischemia may contribute to left ventricular impairment during reperfusion after prolonged coronary artery occlusion. Attenuation of such ischemia in microvessels with impaired erythrocyte flow may require delivery of oxygen at high levels in plasma. Intraarterial infusion of aqueous oxygen (AO) can be used in a site specific manner to achieve hyperoxemic levels of oxygenation in the perfusate. With this new approach, the hypothesis was tested that reperfusion microvascular ischemia can be attenuated. After a 90 min coronary balloon occlusion in a canine model, AO hyperoxemic intracoronary perfusion was performed for 90 min after a 30 min period of autoreperfusion. Control groups consisted of normoxemic reperfusion, both passive (autoreperfusion) and active (roller pump). A significant improvement in left ventricular ejection fraction (p < 0.05) at 2 hr of reperfusion was noted only in the AO hyperoxemia group (17 +/- 6% by two dimensional echo), without a significant reduction in the improvement 1 hr after termination of treatment. During AO hyperoxemic perfusion, ECG ST segment isoelectric deviation normalized, and frequency of ventricular premature contractions was significantly reduced, in contrast to the autoreperfusion control group (p < 0.05). Microvascular blood flow, measured as the ischemic/normal left ventricular segment ratio by radiolabeled microspheres immediately after AO hyperoxemic perfusion, was double the value of the autoreperfusion control group at 2 hr of reperfusion (p < 0.05). We conclude that reperfusion microvascular ischemia is attenuated by intracoronary AO hyperoxemic perfusion and acutely improves left ventricular function in this model.

Objectives: The objectives of the study were to test the hypothesis that hyperbaric levels of oxygen enhance the sensitivity of a sarcoma cell line to doxorubicin (Adriamycin) both in vitro and in vivo in a rat model of pulmonary metastases and to test the feasibility of arterialization of mixed venous blood by direct injection of aqueous oxygen into the pulmonary artery in a rat model., Methods: Rat sarcoma (MCA-2) cells were incubated in the presence of increasing concentrations of doxorubicin (0.1-2.0 micromol/L). A dose-dependent toxicity relationship at 12 hours of treatment was examined with and without pretreatment with hyperbaric oxygen (3.7 atm absolute for 1.5-3.5 hours). In vivo, Sprague-Dawley rats (n = 24) were injected intravenously with 10(6) MCA-2 cells, and the lung tumors were allowed to mature for 14 days. At that time the animals were divided into four groups: control (no treatment), doxorubicin at 2 mg/kg, hyperbaric oxygen (oxygen at 2 atm absolute for 30 minutes), and hyperbaric oxygen plus doxorubicin. Seven days after treatment, the numbers of lung nodules were counted and the lung weights were determined. In additional rats (n = 7), aqueous oxygen (1 mL oxygen/g saline solution) was infused into the pulmonary artery to determine whether arterialization of mixed venous blood was comparable to pulmonary artery oxygenation with a hyperbaric chamber (n = 7)., Results: Hyperbaric oxygen plus doxorubicin produced significantly greater cytolysis of MCA-2 cells (P <.01) than did doxorubicin alone. Hyperbaric oxygen plus doxorubicin also significantly decreased the number of lung metastases and the lung weight relative to doxorubicin alone (P <.01 and P <.01, respectively). The feasibility of arterialization of mixed venous blood (>100 mm Hg) with aqueous oxygen infusion was demonstrated., Conclusions: Hyperbaric oxygen enhanced the chemotherapeutic effect of doxorubicin both in cell culture and in the rat model. Aqueous oxygen infusion can be used to oxygenate mixed venous blood at levels similar to those obtained with the use of a hyperbaric chamber.

Objectives: The purpose of the study was to test the hypothesis that intracoronary aqueous oxygen (AO) hyperbaric reperfusion reduces myocardial injury after prolonged coronary occlusion. Background. Attenuation of ischemia/reperfusion injury by the use of hyperbaric oxygen (HBO) administered during reperfusion has been demonstrated for a wide variety of tissues, including myocardium. We have recently developed a more practical, catheter-based, site-specific method for delivery of oxygen at hyperbaric levels with aqueous oxygen infusion., Methods: Following a 60-minute balloon occlusion of the left anterior descending coronary artery in swine, intracoronary AO hyperoxemic perfusion (50 mL blood/minute; 1.5 mL AO/minute; mean pO2 = 834 104 mmHg) was performed for 90 minutes after a 15-minute period of normoxemic autoreperfusion (physiologic reperfusion). Control groups consisted of autoreperfusion alone; active normoxemic perfusion (50 mL/minute) for 90 minutes; and hyperoxemic perfusion with a hollow fiber oxygenator (HFO) for 90 minutes. Results. A significant improvement in left ventricular ejection fraction was noted by ventriculography at 105 minutes of reperfusion (ANOVA, p < 0.05), compared to the 15-minute autoreperfusion period, only in the AO and HFO groups. Mean percent infarct size (area of necrosis)/(area at risk), quantitative post-mortem hemorrhage score, and myocardial myeloperoxidase levels at 3 hours of reperfusion were significantly less in the AO group (ANOVA, p < 0.05), but not in the HFO group, compared to normoxemic groups. Conclusions. The results demonstrate that intracoronary hyperbaric reperfusion with AO, but not with a membrane oxygenator, attenuates myocardial ischemia/reperfusion injury.

Normal saline (NS) is commonly used as a coronary catheter flush solution. We tested the hypothesis that intracoronary (i.c.) infusions of lactated Ringer's solution (LR) and LR with 5% dextrose (D5LR), both of which contain potassium and calcium, would be associated with less prominent surface ECG changes compared with i.c. infusions of NS. In 34 patients, 10 mL each of NS, LR, and D5LR at 37 degrees C were infused over 5 sec into the left main coronary artery. A 12-lead ECG was recorded before, continuously during, and after each infusion. Blinded ECG analysis revealed T-wave amplitude changes > 0.2 mV in 94%, 12%, and 3% of patients with the use of i.c. NS, D5LR, and LR, respectively (P < 0.0001, NS vs. D5LR or LR). QT prolongation > 40 msec occurred in 88%, 15%, and 18% of patients with i.c. NS, D5LR, and LR, respectively (P < 0.0001, NS vs. D5LR or LR). QT dispersion was increased by > 40 msec in 26% of patients during i.c. NS infusion compared to only 3% of patients with i.c. LR and D5LR infusions (P < 0.01). In conclusion, i.c. NS infusion is associated with more marked repolarization changes as compared with i.c. LR and D5LR infusions. Since such changes may lower arrhythmogenesis thresholds, the routine use of LR as a coronary catheter flush solution should be considered. Cathet. Cardiovasc. Intervent. 48:359-364, 1999., (Copyright 1999 Wiley-Liss, Inc.)

We report on treatment of a patient in whom failure to deploy the distal portion of a Palmaz-Schatz stent occurred but was not recognized. After an unstable course, the patient underwent repeat coronary angiography, at which time the stent was rewired and redilated. Full deployment of the stent with restoration of TIMI grade 3 flow was achieved. The putative cause of the problem, incomplete deployment of the stent because of inadvertent advancement of the stent delivery sheath, should be avoided, and needs to be recognized if it occurs. Crossing and redilating the stent is possible, although technically difficult.