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排序方式: 共有2580条查询结果,搜索用时 15 毫秒
91.
James K. Min Troy M. Labounty Millie J. Gomez Stephan Achenbach Mouaz Al-Mallah Matthew J. Budoff Filippo Cademartiri Tracy Q. Callister Hyuk-Jae Chang Victor Cheng Kavitha M. Chinnaiyan Benjamin Chow Ricardo Cury Augustin Delago Allison Dunning Gudrun Feuchtner Martin Hadamitzky Jorg Hausleiter Philipp Kaufmann Yong-Jin Kim Jonathon Leipsic Fay Y. Lin Erica Maffei Gilbert Raff Leslee J. Shaw Todd C. Villines Daniel S. Berman 《Atherosclerosis》2014
Background
Coronary artery disease (CAD) diagnosis by coronary computed tomographic angiography (CCTA) is useful for identification of symptomatic diabetic individuals at heightened risk for death. Whether CCTA-detected CAD enables improved risk assessment of asymptomatic diabetic individuals beyond clinical risk factors and coronary artery calcium scoring (CACS) remains unexplored.Methods
From a prospective 12-center international registry of 27,125 individuals undergoing CCTA, we identified 400 asymptomatic diabetic individuals without known CAD. Coronary stenosis by CCTA was graded as 0%, 1–49%, 50–69%, and ≥70%. CAD was judged on a per-patient, per-vessel and per-segment basis as maximal stenosis severity, number of vessels with ≥50% stenosis, and coronary segments weighted for stenosis severity (segment stenosis score), respectively. We assessed major adverse cardiovascular events (MACE) – inclusive of mortality, nonfatal myocardial infarction (MI), and late target vessel revascularization ≥90 days (REV) – and evaluated the incremental utility of CCTA for risk prediction, discrimination and reclassification.Results
Mean age was 60.4 ± 9.9 years; 65.0% were male. At a mean follow-up 2.4 ± 1.1 years, 33 MACE occurred (13 deaths, 8 MI, 12 REV) [8.25%; annualized rate 3.4%]. By univariate analysis, per-patient maximal stenosis [hazards ratio (HR) 2.24 per stenosis grade, 95% confidence interval (CI) 1.61–3.10, p < 0.001], increasing numbers of obstructive vessels (HR 2.30 per vessel, 95% CI 1.75–3.03, p < 0.001) and segment stenosis score (HR 1.14 per segment, 95% CI 1.09–1.19, p < 0.001) were associated with increased MACE. After adjustment for CAD risk factors and CACS, maximal stenosis (HR 1.80 per grade, 95% CI 1.18–2.75, p = 0.006), number of obstructive vessels (HR 1.85 per vessel, 95% CI 1.29–2.65, p < 0.001) and segment stenosis score (HR 1.11 per segment, 95% CI 1.05–1.18, p < 0.001) were associated with increased risk of MACE. Beyond age, gender and CACS (C-index 0.64), CCTA improved discrimination by maximal stenosis, number of obstructive vessels and segment stenosis score (C-index 0.77, 0.77 and 0.78, respectively). Similarly, CCTA findings improved risk reclassification by per-patient maximal stenosis [integrated discrimination improvement (IDI) index 0.03, p = 0.03] and number of obstructive vessels (IDI index 0.06, p = 0.002), and by trend for segment stenosis score (IDI 0.03, p = 0.06).Conclusion
For asymptomatic diabetic individuals, CCTA measures of CAD severity confer incremental risk prediction, discrimination and reclassification on a per-patient, per-vessel and per-segment basis. 相似文献92.
Robert C. Lynall J. Troy Blackburn Kevin M. Guskiewicz Stephen W. Marshall Prudence Plummer Jason P. Mihalik 《Journal of Science and Medicine in Sport》2019,22(5):503-508
Objectives
Despite evidence for increased musculoskeletal injury after concussion recovery, there is a lack of dynamic balance assessments that could inform management and research into this increased injury risk post-concussion. Our purpose was to identify tandem gait dynamic balance deficits in recreational athletes with a concussion history within the past 18-months compared to matched controls.Design
Cross-sectional, laboratory study.Methods
Fifteen participants with a concussion history (age: 19.7 ± 0.9 years; 9 females; median time since concussion 126 days, range 28–432 days), and 15 matched controls (19.7 ± 1.6 years; 9 females) with no recent concussion history participated. We measured center-of-pressure (COP) outcomes (velocity, path length, speed, dual-task cost) under 4 tandem gait conditions: (1) tandem gait, (2) tandem gait, eyes closed, (3) tandem gait, eyes open, cognitive distraction, and (4) tandem gait, eyes closed, cognitive distraction.Results
The concussion history group demonstrated slower tandem gait velocity compared to the control group (4.0 cm/s difference), thus velocity was used as a covariate when analyzing COP path length and speed. The concussion history group (23.5%) demonstrated greater COP speed dual-task cost than the control group (16.3%) during the eyes closed dual-task condition. No other comparisons were statistically significant.Conclusions
There may be subtle dynamic balance differences during tandem gait that are detectable after return-to-activity following concussion, but the clinical significance of these findings is unclear. Longitudinal investigations should identify acute movement deficits in varying visual and cognitive scenarios after concussion in comparison with recovery on traditional concussion assessment tools while also recording musculoskeletal injury outcomes. 相似文献93.
Troy H. Middleton M.D. Ossama Al-Mefty M.D. Louis H. Harkey M.D. Andrew D. Parent M.D. John L. Fox M.D. 《Surgical neurology》1987,28(6):458-462
We describe a case of cervical spondylotic myelopathy in which deterioration occurred a month after decompressive laminectomy. Syringomyelia was then in evidence as seen by myelography and delayed metrizamide computed tomography scanning. The etiology of this finding and its possible relation to the course and treatment of cervical spondylotic myelopathy are discussed. 相似文献
94.
Thomas J Forbes Phillip Moore Carlos A C Pedra Evan M Zahn David Nykanen Zahid Amin Swati Garekar David Teitel Shakeel A Qureshi John P Cheatham Makram R Ebeid Ziyad M Hijazi Satinder Sandhu Donald J Hagler Horst Sievert Thomas E Fagan Jeremy Ringwald Wei Du Liwen Tang David F Wax John Rhodes Troy A Johnston Thomas K Jones Daniel R Turner Robert Pass Alejandro Torres William E Hellenbrand 《Catheterization and cardiovascular interventions》2007,70(4):569-577
BACKGROUND: We report a multiinstitutional study on intermediate-term outcome of intravascular stenting for treatment of coarctation of the aorta using integrated arch imaging (IAI) techniques. METHODS AND RESULTS: Medical records of 578 patients from 17 institutions were reviewed. A total of 588 procedures were performed between May 1989 and Aug 2005. About 27% (160/588) procedures were followed up by further IAI of their aorta (MRI/CT/repeat cardiac catheterization) after initial stent procedures. Abnormal imaging studies included: the presence of dissection or aneurysm formation, stent fracture, or the presence of reobstruction within the stent (instent restenosis or significant intimal build-up within the stent). Forty-one abnormal imaging studies were reported in the intermediate follow-up at median 12 months (0.5-92 months). Smaller postintervention of the aorta (CoA) diameter and an increased persistent systolic pressure gradient were associated with encountering abnormal follow-up imaging studies. Aortic wall abnormalities included dissections (n = 5) and aneurysm (n = 13). The risk of encountering aortic wall abnormalities increased with larger percent increase in CoA diameter poststent implant, increasing balloon/coarc ratio, and performing prestent angioplasty. Stent restenosis was observed in 5/6 parts encountering stent fracture and neointimal buildup (n = 16). Small CoA diameter poststent implant and increased poststent residual pressure gradient increased the likelihood of encountering instent restenosis at intermediate follow-up. CONCLUSIONS: Abnormalities were observed at intermediate follow-up following IS placement for treatment of native and recurrent coarctation of the aorta. Not exceeding a balloon:coarctation ratio of 3.5 and avoidance of prestent angioplasty decreased the likelihood of encountering an abnormal follow-up imaging study in patients undergoing intravascular stent placement for the treatment of coarctation of the aorta. We recommend IAI for all patients undergoing IS placement for treatment of CoA. 相似文献
95.
Malasana G Day JD Weiss JP Crandall BG Bair TL May HT Osborn JS Anderson JL Muhlestein JB Lappe DL Nelson J Bunch TJ 《Journal of cardiovascular electrophysiology》2011,22(7):761-766
A Strategy of Rapid Cardioversion. Background: The significance of early recurrent atrial tachyarrhythmias after atrial fibrillation (AF) ablation is unclear. Atrial remodeling driven by these tachyarrhythmias can result in electrical, contractile, and structural changes that may impair long‐term therapy success. Aggressive attempts to restore sinus rhythm in the temporal period of healing after ablation might improve outcomes. Methods: A total of 1,759 AF ablations were performed at Intermountain Medical Center or LDS Hospital. A total of 455 of those were among patients requiring repeat ablations. Patients were instructed to take their pulse daily and, if greater than 100 bpm or irregular, present the following business day fasting to the clinic for evaluation and cardioversion if AF or atrial flutter (AFL) were present. Results: Of the ablations performed, a total of 515 (29%, age: 65.6 ± 11.2 years, male: 57.9%) developed AF/AFL that required cardioverison. The majority of these arrhythmias first occurred in the initial 90 days (63.7%) postablation. During this period, 62.8% were on an antiarrhythmic drug (AAD). Only 25.1% were using an AAD at 3 months. The majority of ablations (75.6%) who experienced AF/AFL within the first 90 days after ablation were in sinus rhythm with no AAD at 1 year. Further, 48% of those with the first recurrence from 90 to 180 days were in sinus rhythm with no AAD at 1 year. Conclusions: The time at which the first recurrence of AF/AFL occurs impacts long‐term outcomes. An aggressive strategy of rapid cardioversion postablation reduces the significance of recurrent AF/AFL during the first 6 months . (J Cardiovasc Electrophysiol, Vol. 22, pp. 761‐766, July 2011) 相似文献
96.
Devarshi R Ardeshna Troy Cao Brandon Rodgers Chidiebere Onongaya Dan Jones Wei Chen Eugene J Koay Somashekar G Krishna 《World journal of gastroenterology : WJG》2022,28(6):624-634
Pancreatic cystic lesions (PCLs) are becoming more prevalent due to more frequent abdominal imaging and the increasing age of the general population. It has become crucial to identify these PCLs and subsequently risk stratify them to guide management. Given the high morbidity associated with pancreatic surgery, only those PCLs at high risk for malignancy should undergo such treatment. However, current diagnostic testing is suboptimal at accurately diagnosing and risk stratifying PCLs. Therefore, research has focused on developing new techniques for differentiating mucinous from non-mucinous PCLs and identifying high risk lesions for malignancy. Cross sectional imaging radiomics can potentially improve the predictive accuracy of primary risk stratification of PCLs at the time of detection to guide invasive testing. While cyst fluid glucose has reemerged as a potential biomarker, cyst fluid molecular markers have improved accuracy for identifying specific types of PCLs. Endoscopic ultrasound guided approaches such as confocal laser endomicroscopy and through the needle microforceps biopsy have shown a good correlation with histopathological findings and are evolving techniques for identifying and risk stratifying PCLs. While most of these recent diagnostics are only practiced at selective tertiary care centers, they hold a promise that management of PCLs will only get better in the future. 相似文献
97.
98.
CT Angiography of the Lower Extremities 总被引:1,自引:0,他引:1
99.
Kenneth Cornetta Jing Yao Aparna Jasti Sue Koop Makhaila Douglas David Hsu Larry A Couture Troy Hawkins Lisa Duffy 《Molecular therapy》2011,19(3):557-566
Lentiviral vectors are now in clinical trials for a variety of inherited and acquired disorders. A challenge for moving any viral vector into the clinic is the ability to screen the vector product for the presence of replication-competent virus. Assay development for replication-competent lentivirus (RCL) is particularly challenging because recombination of vector packaging plasmids and cellular DNA leading to RCL has not been reported with the current viral vector systems. Therefore, the genomic structure of a RCL remains theoretical. In this report, we describe a highly sensitive RCL assay suitable for screening vector product and have screened large-scale vector supernatant, cells used in vector production, and cells transduced with clinical grade vector. We discuss the limitations and challenges of the current assay, and suggest modifications that may improve the suitability of this assay for screening US Food and Drug Administration (US FDA)-licensed products. 相似文献
100.