17 results on '"Akyuz K"'
Search Results
2. AB0634 Variability in Phenotype Clusters in Behçet’s Syndrome: A Systematic Review
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Macit, B., primary, Akyuz, K., additional, Esatoglu, S. N., additional, and Hatemi, G., additional
- Published
- 2022
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3. Novel risk model for one-year mortality and guidance of management strategy in isolated severe secondary tricuspid regurgitation
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Wang, T K M, primary, Mentias, A, additional, Akyuz, K, additional, Kirincich, J, additional, Duran Crane, A, additional, Pettersson, G B, additional, Gillinov, A M, additional, Popovic, Z B, additional, Xu, B, additional, Griffin, B P, additional, and Desai, M Y, additional
- Published
- 2021
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4. Earlier surgery improves long-term survival compared to class I surgical indications and infective endocarditis surgery for isolated severe tricuspid regurgitation
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Wang, T.K.M, primary, Akyuz, K, additional, Xu, B, additional, Gillinov, M, additional, Pettersson, G, additional, Griffin, B.P, additional, and Desai, M.Y, additional
- Published
- 2020
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5. Peripheral Blood Eosinophilia and Neutrophil Lymphocyte Rate in Antibiotic and/or Patients Hospitalized with COPD Exacerbations
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Kose, N., primary, Karakurt, Z., additional, Gundogus, B., additional, Gungor, A., additional, Akyuz, K., additional, and Turker, H., additional
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- 2020
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6. P.8.b.005 Assessment of patients with morbid obesity prior to bariatric surgery (sleeve gastrectomy)
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Garayeva, K., primary, Akyuz, K., additional, Yuksek, E., additional, Gultekm, G., additional, Taskm, H.E, additional, Taskin, M., additional, Zengin, S.U, additional, and Emul, M., additional
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- 2015
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7. Selectivity of heavy metal binding by algal polysaccharides
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Guven, K. C., Akyuz, K., and Yurdun, T.
- Abstract
The selectivity of heavy metal binding by algal polysaccharides such as alginic acid, carrageenan types and agar was investigated. Lead was retained in highest amounts by alginate.Algal polysaccharides were ranked as: Sodium alginate > carrageenans > agar for metal binding.The functional groups of algal polysaccharides are found to be effective in heavy metal binding selectivity and those containing carboxylic groups retained heavy metals higher than those with sulphate groups.
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- 1995
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8. Predicting Long-Term Clinical Outcomes of Patients With Recurrent Pericarditis.
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Yesilyaprak A, Kumar AK, Agrawal A, Furqan MM, Verma BR, Syed AB, Majid M, Akyuz K, Rayes DL, Chen D, Kai Ming Wang T, Cremer PC, and Klein AL
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- Humans, Female, Male, Middle Aged, Retrospective Studies, Adult, Risk Assessment methods, Machine Learning, Prognosis, Pericarditis diagnosis, Recurrence
- Abstract
Background: Recurrent pericarditis (RP) is a complex condition associated with significant morbidity. Prior studies have evaluated which variables are associated with clinical remission. However, there is currently no established risk-stratification model for predicting outcomes in these patients., Objectives: We developed a risk stratification model that can predict long-term outcomes in patients with RP and enable identification of patients with characteristics that portend poor outcomes., Methods: We retrospectively studied a total of 365 consecutive patients with RP from 2012 to 2019. The primary outcome was clinical remission (CR), defined as cessation of all anti-inflammatory therapy with complete resolution of symptoms. Five machine learning survival models were used to calculate the likelihood of CR within 5 years and stratify patients into high-risk, intermediate-risk, and low-risk groups., Results: Among the cohort, the mean age was 46 ± 15 years, and 205 (56%) were women. CR was achieved in 118 (32%) patients. The final model included steroid dependency, total number of recurrences, pericardial late gadolinium enhancement, age, etiology, sex, ejection fraction, and heart rate as the most important parameters. The model predicted the outcome with a C-index of 0.800 on the test set and exhibited a significant ability in stratification of patients into low-risk, intermediate-risk, and high-risk groups (log-rank test; P < 0.0001)., Conclusions: We developed a novel risk-stratification model for predicting CR in RP. Our model can also aid in stratifying patients, with high discriminative ability. The use of an explainable machine learning model can aid physicians in making individualized treatment decision in RP patients., Competing Interests: Funding Support and Author Disclosures Dr Cremer has served on the scientific advisory board of Kiniksa Pharmaceuticals and Cardiol Therapeutics. Dr Klein has received a research grant from Kiniksa Pharmaceuticals, Ltd, and Cardiol Therapeutics; and has served on the scientific advisory board of Kiniksa Pharmaceuticals, Ltd, Pfizer, Inc, and Cardiol Therapeutics. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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9. Echocardiography Versus Magnetic Resonance Imaging Quantification and Novel Algorithm for Isolated Severe Tricuspid Regurgitation.
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Wang TKM, Reyaldeen R, Akyuz K, Popovic ZB, Gillinov AM, Xu B, Griffin BP, and Desai MY
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- Humans, Echocardiography methods, Magnetic Resonance Imaging, Heart Ventricles, Algorithms, Tricuspid Valve Insufficiency diagnostic imaging
- Abstract
Transthoracic echocardiography (TTE) is the first-line tool to evaluate isolated tricuspid regurgitation (TR) but it has limitations and its TR quantification compared with magnetic resonance imaging (MRI) has been studied infrequently. We compared isolated severe TR quantification by TTE against MRI and developed a novel TTE-based algorithm. Isolated TR patients graded severe by TTE and who underwent MRI January 2007 to June 2019 were studied. The TTE and MRI measurements were analyzed by correlation, area under receiver-operative characteristics curve (AUC), and classification and regression tree algorithm of TTE parameters to best identify MRI-derived severe TR (regurgitant volume ≥45 ml and/or fraction ≥50%). A total of 108 of 262 (41%) that were graded as severe TR by TTE also had severe TR by MRI. There were moderate correlations between TTE and MRI in the quantification of TR severity and right atrial size (Pearson r = 0.428 to 0.645) but none to modest correlations between them in right ventricle quantification. The key TTE parameters to identify MRI-derived severe TR in the decision tree regression algorithm were right atrial volume indexed ≥47 ml/m
2 and effective regurgitant orifice area ≥0.45 cm2 and especially if there is right ventricle free wall strain ≥ -9.5%. This novel algorithm has an AUC of 0.76% and 79% agreement to detect severe TR by MRI, which higher than the American Society of Echocardiography criteria with AUC 0.68% and 66% agreement (p = 0.006 and p <0.001, respectively). In conclusion, TTE-derived TR and right atrial quantification had moderate correlation and discrimination of severe TR by MRI, from which a novel TTE algorithm was derived, which had incrementally a higher accuracy than contemporary guidelines' criteria alone., Competing Interests: Declaration of Competing Interest Dr. Desai has research and consultant agreements with Myokardia Inc, Medtronic, and Silence therapeutics. Dr. Gillinov is a consultant for AtriCure, Medtronic, Edwards, CryoLife, Abbott, Johnson and Johnson, and ClearFlow and has right to equity in ClearFlow. The remining authors have no competing interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)- Published
- 2024
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10. Early surgery is associated with improved long-term survival compared to class I indication for isolated severe tricuspid regurgitation.
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Wang TKM, Akyuz K, Xu B, Gillinov AM, Pettersson GB, Griffin BP, and Desai MY
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- Female, Humans, Adult, Middle Aged, Aged, Treatment Outcome, Proportional Hazards Models, Retrospective Studies, Tricuspid Valve Insufficiency diagnostic imaging, Tricuspid Valve Insufficiency surgery, Tricuspid Valve Insufficiency complications, Heart Valve Prosthesis Implantation adverse effects, Cardiac Surgical Procedures
- Abstract
Background: Isolated tricuspid valve (TV) surgery has higher mortality compared with other single-valve operations. The optimal timing and indications remain controversial, and earlier surgery before the development of class I surgical indications may improve outcomes. We aimed to compare the characteristics and outcomes of surgery for isolated tricuspid regurgitation (TR), based on class I indication versus an earlier operation., Methods: Consecutive patients undergoing isolated TV surgery for TR without other concomitant valve surgery at our center during 2004 to 2018 were studied. Indications were divided into class I versus earlier surgery (asymptomatic severe TR with right ventricular dilation and/or dysfunction) for comparative analyses of characteristics and outcomes. The primary outcome was mortality., Results: The study included 159 patients (91 females [57.2%]; 115 for class I, 44 for early surgery), with a mean age of 59.7 ± 15.6 years, 119 (74.8%) with surgical repairs, and a mean follow-up of 5.1 ± 4.0 years. Overall operative mortality was 5.1% (8 patients) (class I, 7.0%; early surgery, 0.0%; P = .107), and class I had a higher composite morbidity than early surgery (35.7% [n = 41] vs 18.2% [n = 8]; P = .036). On Cox proportional hazard model analysis, class I versus early surgery (hazard ratio [HR], 4.62; 95% confidence interval [CI], 1.09-19.7; P = .04), age (HR, 1.03; 95% CI, 1.00-1.07; P = .046), and diabetes (HR, 2.50; 95% CI, 1.13-5.55; P = .024) were independently associated with higher mortality during follow-up., Conclusions: Patients with class I indication for isolated TV surgery had worse survival compared with those undergoing earlier surgery before reaching class I indication. Earlier surgery may improve outcomes in these high-risk patients., (Copyright © 2021 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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11. Quantitative Echocardiographic Assessment and Optimal Criteria for Early Intervention in Asymptomatic Tricuspid Regurgitation.
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Akintoye E, Wang TKM, Nakhla M, Ali AH, Fava AM, Akyuz K, Popovic ZB, Pettersson GB, Gillinov AM, Xu B, Griffin BP, and Desai MY
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- Humans, Female, Aged, Male, Tricuspid Valve diagnostic imaging, Retrospective Studies, Predictive Value of Tests, Echocardiography, Severity of Illness Index, Tricuspid Valve Insufficiency surgery
- Abstract
Background: Significant tricuspid regurgitation (TR) is associated with poor outcome and high operative mortality resulting from late presentation. Yet, the optimal timing for intervention is unknown., Objectives: The purpose of this study was to evaluate the prognostic value of echocardiographic parameters to inform early intervention in asymptomatic TR., Methods: Using the Cleveland Clinic echocardiography database 2004 to 2018, the authors identified a consecutive cohort of asymptomatic patients with moderate to severe (3+) or severe (4+) TR. Quantitative TR and right heart parameters were retrospectively determined, and their prognostic utility for all-cause mortality was assessed., Results: In 325 asymptomatic patients (mean age: 67.9 years; 79.4% female) with at least 3+ TR, there were 132 deaths (40.6%), with a median survival time of 9.9 years (95% CI: 7.9-12.7 years). By contrast, the median survival time in an age- and sex-matched cohort of symptomatic TR patients was 4.4 years (95% CI: 2.8-5.9 years). Among all the echocardiographic parameters evaluated, right ventricle free wall strain (RVFWS) and tricuspid regurgitant volume (RVol) were the strongest predictors of mortality in asymptomatic TR. The optimal discriminatory thresholds for these parameters were RVFWS <-19% and RVol >45 mL. The 5-year survival rates by number of risk factors (RF) were 93% (95% CI: 86%-96%), 65% (95% CI: 55%-74%), and 38% (95% CI: 26%-49%) for no RF, 1 RF, and both RFs, respectively. Compared with symptomatic TR, mortality was lower for asymptomatic TR with no RF (HR: 0.10; 95% CI: 0.04-0.29) or 1 RF (HR: 0.29; 95% CI: 0.14-0.58), but similar for asymptomatic TR with both RFs (HR: 1.11; 95% CI: 0.56-2.19)., Conclusions: RVFWS and RVol are key prognostic markers that can be serially monitored to inform optimal timing of intervention for severe asymptomatic TR., Competing Interests: Funding Support and Author Disclosures Dr Gillinov has served as a consultant to AtriCure, Medtronic, Edwards Lifesciences, CryoLife, Abbott, and ClearFlow; and has rights to equity in ClearFlow. Dr Desai has been supported by the Haslam Family endowed chair in cardiovascular medicine at the Cleveland Clinic. The current research was supported by a philanthropic gift from the Haslam family, Bailey family, and Khouri family. Dr Desai has research and consulting agreements with Bristol Myers Squibb, Medtronic, and Caristo Diagnostics. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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12. Contemporary Etiologies, Outcomes, and Novel Risk Score for Isolated Tricuspid Regurgitation.
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Wang TKM, Akyuz K, Mentias A, Kirincich J, Duran Crane A, Xu S, Popovic ZB, Xu B, Gillinov AM, Pettersson GB, Griffin BP, and Desai MY
- Subjects
- Aged, Aged, 80 and over, Echocardiography, Female, Humans, Male, Middle Aged, Predictive Value of Tests, Retrospective Studies, Risk Factors, Treatment Outcome, Heart Valve Diseases complications, Tricuspid Valve Insufficiency diagnostic imaging, Tricuspid Valve Insufficiency epidemiology, Tricuspid Valve Insufficiency etiology
- Abstract
Objectives: The authors report etiologies and outcomes and devise a risk model in a large contemporary cohort of patients with isolated tricuspid regurgitation (TR)., Background: Isolated TR is a challenging clinical entity with heterogeneous etiology and often poor outcomes, with a paucity of recent research regarding the epidemiology of isolated TR., Methods: Consecutive patients with isolated TR graded at least moderate to severe on echocardiography from January 2004 to December 2018 (n = 9,045, mean age 70.4 ± 15.4 years, 60.3% women) were studied. TR etiologies were individually adjudicated as secondary or primary, with subcategories. All-cause death during follow-up was the primary endpoint, with associations between etiology and outcomes analyzed and a risk model created., Results: Primary and secondary TR etiologies were present in 470 (5.2%) and 8,575 (94.8%) patients, respectively. The main secondary etiologies were left heart disease in 4,664 (54.4%), atrial functional in 2,086 (24.3%), and pulmonary disease in 1,454 (17.0%), and the main primary etiologies were endocarditis in 222 (47.2%), degenerative or prolapse in 86 (18.3%), and prosthetic valve failure in 79 (16.8%). There were 3,987 deaths (44.0%) over a mean follow-up period of 2.6 ± 3.3 years. In unadjusted analyses, patients with secondary TR had worse survival than those with primary TR (HR: 1.56; 95% CI: 1.32-1.85), but this result was not statistically significant in multivariable analysis. The authors devised and internally validated a risk score for predicting 1-year mortality in these patients., Conclusions: Secondary TR constituted 95% of isolated significant TR and conferred worse survival than primary TR in unadjusted but not adjusted analyses. The present novel risk score stratifies the risk for 1-year death and may influence decision making for management in these high-risk patients., Competing Interests: Funding Support and Author Disclosures Dr Wang is supported by the National Heart Foundation of New Zealand Overseas Clinical and Research Fellowship (grant 1775). Dr Desai is supported by the Haslam Family endowed chair in cardiovascular medicine at the Cleveland Clinic, a generous philanthropic gift from the Haslam family, Bailey family, and Khouri family. Dr Desai has research and consulting agreements with Myokardia, Medtronic, and Silence Therapeutics. Dr Gillinov is a consultant to AtriCure, Medtronic, Edwards Lifesciences, CryoLife, Abbott, Johnson & Johnson, and ClearFlow; and has rights to equity in ClearFlow. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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13. Effect of Tricuspid Valve Repair or Replacement on Survival in Patients With Isolated Severe Tricuspid Regurgitation.
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Wang TKM, Mentias A, Akyuz K, Kirincich J, Crane AD, Popovic ZB, Xu B, Gillinov AM, Pettersson GB, Griffin BP, and Desai MY
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- Aged, Aged, 80 and over, Cohort Studies, Female, Hospital Mortality, Hospitalization, Humans, Male, Middle Aged, Severity of Illness Index, Survival Rate, Time Factors, Treatment Outcome, Heart Valve Prosthesis Implantation, Tricuspid Valve Insufficiency mortality, Tricuspid Valve Insufficiency surgery
- Abstract
Controversies remain in the management strategy for isolated tricuspid regurgitation (TR) because of adverse prognosis and uncertainties regarding the benefits of tricuspid valve surgery. We compared the characteristics and outcomes of a large cohort of patients with isolated TR, based on downstream tricuspid valve surgery versus medical management. Consecutive patients with isolated TR graded at least moderate-to-severe by echocardiography identified between January 2004 and December 2018 (n = 9,031, age 70 ± 15 years, 60% women) were retrospectively studied. The primary end point was time to all-cause mortality during follow-up. Outcomes were compared by management strategy using unadjusted and adjusted survival and multivariable regression analyses. Tricuspid valve surgery was performed in 632 of 9,031 of the cohort (7%), including 514 valve repairs and 118 valve replacements, with in-hospital mortality in 19 patients (2.9%). Overall, there were 3,985 all-cause deaths (44%) over mean follow-up of 2.6 ± 3.3 years. Tricuspid valve surgery was independently associated with lower mortality rate during follow-up, with hazard ratios (HRs) of 0.53 (95% confidence interval [CI] 0.45 to 0.64), and the association persisted in both primary and secondary TR subgroups. Tricuspid valve surgery also had a significantly higher rate of infective endocarditis and heart failure hospitalizations rates during follow-up, at HRs of 5.55 (95% CI 4.00 to 7.71) and 1.29 (95% CI 1.16 to 1.43), respectively. In conclusion, tricuspid valve surgery is rarely performed in isolated TR, but it is independently associated with greater survival for the overall cohort and both primary and secondary etiology subgroups. Increasing the utilization of this surgery at specialized centers is encouraged to try to improve the clinical outcomes for this challenging clinical entity., Competing Interests: Disclosures Dr. Desai has research and consultant agreements with Myokardia Inc, Medtronic, Silence therapeutics, and Caristo Diagnostics. Dr. Gillinov is consultant to AtriCure, Medtronic, Edwards, CryoLife, Abbott, Johnson and Johnson, and ClearFlow and has right to equity for ClearFlow. The other authors have no conflicts of interest to declare., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2022
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14. Comparison of risk scores for predicting outcomes after isolated tricuspid valve surgery.
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Wang TKM, Akyuz K, Kirincich J, Duran Crane A, Mentias A, Xu B, Gillinov AM, Pettersson GB, Griffin BP, and Desai MY
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- Adult, Aged, Cohort Studies, Female, Humans, Middle Aged, Retrospective Studies, Risk Assessment, Risk Factors, Severity of Illness Index, Tricuspid Valve diagnostic imaging, Tricuspid Valve surgery, Cardiac Surgical Procedures, End Stage Liver Disease, Heart Valve Prosthesis Implantation
- Abstract
Background: Risk models play important roles in stratification and decision-making towards cardiac surgery. Isolated tricuspid valve surgery is a high risk but increasingly performed the operation, however, the performance of risk models has not been externally evaluated in these patients. We compared the prognostic utility of contemporary risk scores for isolated tricuspid valve surgery., Methods: Consecutive patients undergoing isolated tricuspid valve surgery at Cleveland Clinic during 2004-2018 were evaluated in this cohort study. EuroSCORE II, Society of Thoracic Surgeon's tricuspid (STS-TVS) score, and the Model for End-stage Liver Disease (MELD) score were retrospectively calculated, and their performance for predicting operative mortality, postoperative complications, and mortality during follow-up was assessed., Results: Amongst 207 patients studied, the mean age was 54.1 ± 17.9 years, 116 (56.0%) were female, 92 (44.4%) had secondary tricuspid regurgitation, and 151 (72.9%) had a surgical repair. Mean EuroSCORE II, STS-TVS, and MELD scores were 6.3 ± 6.6%, 5.5 ± 6.2%, and 9.8 ± 4.7, respectively. C-statistics (95% confidence intervals) for operative mortality were 0.83 (0.74-0.93) for EuroSCORE II, 0.60 (0.45-0.75) for STS-TVS score, and 0.74 (0.58-0.89) for MELD score, while observed/expected ratios were 0.78 and 0.89 for the first two scores. All three scores were associated with mortality during follow-up and discriminated most postoperative complications., Conclusion: EuroSCORE II was superior to STS-tricuspid score for isolated TVS risk assessment. Although surgical risk scores traditionally underestimated operative mortality after isolated tricuspid valve surgery, they did not in our cohort, reflecting the excellent surgical results. The simple MELD score performed similarly to the EuroSCORE II, especially for discriminating morbidities., (© 2021 Wiley Periodicals LLC.)
- Published
- 2022
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15. Prognostic Value of Complementary Echocardiography and Magnetic Resonance Imaging Quantitative Evaluation for Isolated Tricuspid Regurgitation.
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Wang TKM, Akyuz K, Reyaldeen R, Griffin BP, Popovic ZB, Pettersson GB, Gillinov AM, Flamm SD, Xu B, and Desai MY
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- Female, Humans, Male, Middle Aged, Prognosis, Reproducibility of Results, Tricuspid Valve Insufficiency physiopathology, Echocardiography methods, Magnetic Resonance Imaging, Cine methods, Tricuspid Valve Insufficiency diagnosis
- Abstract
Background: Isolated tricuspid regurgitation (TR) remains a management dilemma with poor outcomes. Echocardiography and cardiac magnetic resonance imaging (CMR) are valuable tools for evaluating TR, but their prognostic utility has rarely been studied together in this setting. We aimed to determine the prognostic value and thresholds for echocardiography and CMR parameters for isolated severe TR., Methods: Consecutive patients with isolated severe TR by echocardiography and undergoing CMR during January 2007 to June 2019 were studied. Echocardiography and CMR-derived quantitative parameters were analyzed for independent associations with and thresholds for predicting the primary end point of all-cause mortality during follow-up., Results: Among 262 patients studied, mean age was 62.8±15.6 years, 156 (59.5%) were females, 207 (79.0%) had secondary TR, and 87 (33.2%) underwent tricuspid valve surgery after CMR. There were 68 (26.0%) deaths during a mean follow-up of 2.5 years. Both CMR-derived tricuspid regurgitant fraction (per 5% increase) and right ventricle free wall longitudinal strain (per 1% decrease in magnitude) were independently associated with worse survival, with hazard ratios (95% CIs) of 1.15 (1.05-1.25) and 1.10 (1.04-1.17), respectively, along with right heart failure symptoms of 2.03 (1.14-3.60), while tricuspid valve surgery was borderline protective with 0.55 (0.31-0.997). Regurgitant fraction ≥30%, regurgitant volume ≥35 mL and right ventricle free wall longitudinal strain ≥-11% (by velocity vector imaging technique, which yields lower magnitude values than other conventional strain techniques) were the optimal thresholds for mortality during follow-up., Conclusions: TR quantification by CMR and right ventricle free wall longitudinal strain by echocardiography were the key imaging parameters independently associated with reduced survival in isolated TR, incremental to conventional clinical factors. Clinically significant thresholds for these parameters were determined and may help guide decision-making for TR management.
- Published
- 2021
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16. Exonic duplication CNV of NDRG1 associated with autosomal-recessive HMSN-Lom/CMT4D.
- Author
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Okamoto Y, Goksungur MT, Pehlivan D, Beck CR, Gonzaga-Jauregui C, Muzny DM, Atik MM, Carvalho CMB, Matur Z, Bayraktar S, Boone PM, Akyuz K, Gibbs RA, Battaloglu E, Parman Y, and Lupski JR
- Subjects
- Adult, Base Sequence, Comparative Genomic Hybridization, Female, Gene Duplication, Gene Expression, Genes, Recessive, Humans, Male, Mutation, Sequence Analysis, DNA, Turkey, Young Adult, Cell Cycle Proteins genetics, Charcot-Marie-Tooth Disease genetics, DNA Copy Number Variations genetics, Intracellular Signaling Peptides and Proteins genetics, Refsum Disease genetics
- Abstract
Purpose: Copy-number variations as a mutational mechanism contribute significantly to human disease. Approximately one-half of the patients with Charcot-Marie-Tooth (CMT) disease have a 1.4 Mb duplication copy-number variation as the cause of their neuropathy. However, non-CMT1A neuropathy patients rarely have causative copy-number variations, and to date, autosomal-recessive disease has not been associated with copy-number variation as a mutational mechanism., Methods: We performed Agilent 8 × 60 K array comparative genomic hybridization on DNA from 12 recessive Turkish families with CMT disease. Additional molecular studies were conducted to detect breakpoint junctions and to evaluate gene expression levels in a family in which we detected an intragenic duplication copy-number variation., Results: We detected an ~6.25 kb homozygous intragenic duplication in NDRG1, a gene known to be causative for recessive HMSNL/CMT4D, in three individuals from a Turkish family with CMT neuropathy. Further studies showed that this intragenic copy-number variation resulted in a homozygous duplication of exons 6-8 that caused decreased mRNA expression of NDRG1., Conclusion: Exon-focused high-resolution array comparative genomic hybridization enables the detection of copy-number variation carrier states in recessive genes, particularly small copy-number variations encompassing or disrupting single genes. In families for whom a molecular diagnosis has not been elucidated by conventional clinical assays, an assessment for copy-number variations in known CMT genes might be considered.
- Published
- 2014
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17. Balancing riparian management and river recreation: methods and applications for exploring floater behavior and their interaction with large wood.
- Author
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Biedenweg K, Akyuz K, and Skeele R
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- Adolescent, Adult, Child, Environmental Monitoring, Female, Geographic Information Systems, Humans, Male, Public Opinion, Risk-Taking, Suburban Population, Washington, Young Adult, Conservation of Natural Resources, Recreation, Rivers, Trees
- Abstract
River managers are tasked with meeting both ecological and human needs. In the Puget Sound lowland, riparian management often includes placing or allowing the presence of large wood to stabilize riverbanks and enhance salmon habitat. Although this practice benefits humans by protecting infrastructure and natural resources, it is unclear how such practices interact with an additional human interest, recreation. Furthermore, we were unable to find studies that describe how an agency can go about researching the interaction between recreation and large wood management practices. This study tested methods for describing and estimating the number of river floaters, where they float in relationship to river projects, the risks they take while floating, and their perceptions of large wood in the river. Selecting a high-use suburban river in Washington State, we used riverside observations, interviews, and an infrared counter to gather data in the summer of 2010. Statistical analyses provided general characteristics of users, trends in engaging in risky behaviors, and estimates of use for the entire season and on the busiest day. Data mapping with GIS presented the density of use along the river and frequency of use of specific float routes. Finally, qualitative analysis of interviews clarified floaters' perspectives of large wood. To address the multiple mandates of river managers, it is important to understand recreation users, the factors that could be putting them at risk, and how the actual users perceive large wood in the river. This study demonstrates methods for scientifically gathering such information and applying it when making riparian management decisions.
- Published
- 2012
- Full Text
- View/download PDF
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