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《Seminars in thoracic and cardiovascular surgery》2020,32(4):990-999
A total of 15 leaflets from 5 failed conduits (group F) and 12 leaflets from 5 nonfailed conduits (group non-F) were evaluated. Macroscopic and histopathologic examination revealed 4 remarkable findings: proliferation of collagenous neointima, existence of lymphocytic inflammation, proteinaceous infiltration into the leaflet, and calcification of the leaflet. There was a significant correlation between appearance probability of calcification in group F and that of proteinaceous infiltration in group non-F, suggesting that proteinaceous infiltration into the leaflet seems to be responsible for leaflet calcification. Modification of the ePTFE material against proteinaceous infiltration may reduce the calcification, and therefore improve the durability of the ePTFE-valved conduit. 相似文献
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Study objectiveFibrinogen concentrate is used to treat severe postpartum hemorrhage despite limited evidence of its effectiveness in obstetric settings. We aimed to explore the association between its administration and maternal outcomes in women with severe postpartum hemorrhage.Design, setting and patientsThis secondary analysis of the EPIMOMS prospective population-based study, exploring severe maternal morbidity, as defined by national expert consensus (2012–2013, 182,309 deliveries, France), included all women with severe postpartum hemorrhage and transfused with red blood cells during active bleeding.MeasurementsThe primary endpoint was maternal near-miss or death, and the secondary endpoint the total number of red blood cells units transfused.InterventionsWe studied fibrinogen concentrate administration as a binary variable and then by the timing of its administration. We used multivariable analysis and propensity score matching to account for potential indication bias.Main resultsAmong the 730 women with severe postpartum hemorrhage and transfused, 313 (42.9%) received fibrinogen concentrate, and 142 (19.5%) met near-miss criteria or died. The risk of near-miss or death was not significantly lower among the women treated with fibrinogen concentrate than among those not treated, in either the multivariable analysis (adjusted RR = 1.03; 95% CI, 0.72–1.49; P = 0.855) or the propensity score analysis (RR = 0.85; 95% CI, 0.55–1.32; P = 0.477). Among women treated with fibrinogen concentrate, administration more than three hours after red blood cell transfusion started was associated with a higher risk of near-miss or death than administration before or within 30 min after the transfusion began (adjusted RR = 2.07; 95% CI, 1.10–3.89; P = 0.024). Results were similar for the secondary endpoint.ConclusionsThe use of fibrinogen concentrate in severe postpartum hemorrhage needing red blood cell transfusion during active bleeding is not associated with improved maternal outcomes. 相似文献
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《Journal of vascular surgery》2020,71(6):1921-1929
ObjectiveIdentifying biomarkers for abdominal aortic aneurysms (AAA) could prove beneficial in prognosis of AAA and thus the selection for treatment. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein that is highly expressed in aorta. MFAP4 is involved in several tissue remodeling-related diseases. We aimed to investigate the potential role of plasma MFAP4 (pMFAP4) as a biomarker of AAA.MethodsPlasma samples and data were obtained for 504 male AAA patients and 188 controls in the Viborg Vascular (VIVA) screening trial. The pMFAP4 levels were measured by Alphalisa. The Mann-Whitney U test assessed differences in pMFAP4 levels between the presence and absence of different exposures of interest. The correlation between pMFAP4 and aorta growth rate were investigated through spearman's correlation analysis. Immunohistochemistry and multiple logistic regression adjusted for potential confounders assessed the association between pMFAP4 and AAA. Multiple linear regression assessed the correlation between pMFAP4 and aorta growth rate. Cox regression and competing risk regression were used to investigate the correlation between AAA patients with upper tertile pMFAP4 and the risk of undergoing later surgical repair.ResultsA significant negative correlation between pMFAP4 and aorta growth rate was observed using spearman's correlation analysis (ρ = −0.14; P = .0074). However, this finding did not reach significance when applying multiple linear regression. A tendency of decreased pMFAP4 was observed in AAA using immunohistochemistry. Competing risk regression adjusted for potential confounders indicated that patients with upper tertile pMFAP4 had a hazard ratio of 0.51 (P = .001) for risk of undergoing later surgical repair.ConclusionsHigh levels of pMFAP4 are associated with a decreased likelihood of receiving surgical repair in AAA. This observation warrants confirmation in an independent cohort. 相似文献
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Background/purposeMachine learning has been used to predict procedural risk in patients undergoing various medical interventions and procedures. One-year mortality in patients after Transcatheter Aortic Valve Replacement (TAVR) has a wide range (from 8.5 to 24% in various studies). We sought to apply machine learning to determine predictors of one year mortality in patients undergoing TAVR.Methods/materialsA retrospective study of 1055 patients who underwent TAVR (Jan 2014–June 2017) with one-year follow up was completed. Baseline demographics, clinical, electrocardiography (ECG), Computed Tomography (CT) and echocardiography data were abstracted. Variables with near zero variance or ≥50% missing data were excluded. The Gradient Boosting Machine learning (GBM) prediction model included 163 variables and was optimized using 5-fold cross-validation repeated 10-times. The receiver operator characteristic (ROC) for the GBM model was calculated to predict one-year mortality post TAVR, and then compared to the TAVI2-SCORE and CoreValve score.ResultsAmong 1055 TAVR patients (mean age 80.9 ± 7.9 years, 42% female), 14.02% died at one year. 78% had balloon expandable valves placed. Based on GBM, the ten most predictive variables for one-year survival were cardiac power index, hemoglobin, systolic blood pressure, INR, diastolic blood pressure, body mass index, valve calcium score, serum creatinine, aortic annulus area, and albumin. The area under ROC to predict survival for the GBM model vs TAVI2-SCORE and CoreValve Score was 0.72 (95% CI 0.68–0.78) vs 0.56 (95%CI 0.51–0.62) and 0.53 (95% CI 0.47–0.59) respectively with p < 0.0001.ConclusionThe GBM model outperforms TAVI2-SCORE and CoreValve Score in predicting mortality one-year post TAVR. 相似文献
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ContextKnee arthroplasty surgery is significant trauma, leading to an activated immune system causing inflammation and oxidative stress. Many current biomarkers are invasive, costly, and often slow to analyse, limiting their use for rapid inflammatory measurements.ObjectivesWe have examined the use of urinary neopterin and total neopterin in knee arthroplasty patients to non-invasively measure oxidative stress and inflammation from immune system activation. We aim to validate the use of these biomarkers for quick, cost effective and predictive measurements of post-surgical inflammation assessment.Methodology19 Knee arthroplasty patients were analysed pre-operatively and for a defined post-operative period to determine the urinary levels of neopterin and total neopterin (neopterin +7,8-dihydroneopterin) using high performance liquid chromatography with fluorescence detection. These results were then compared to a control group of 20 participants with normal knee function.Results7,8-Dihydroneopterin was stable in urine over 12 h when refrigerated. Knee arthritis was associated with an increase in pre-operative neopterin (oxidative stress) and total neopterin (inflammation). The subsequent arthroplasty surgery generated a significant increase neopterin and total neopterin. Both biomarkers were reduced immediately post-operatively, before becoming elevated on the following days. There was no clear evidence of an association between initial neopterin and total neopterin levels and a patient's level of inflammation during in-hospital recovery.ConclusionsThe stability of 7,8-dihydroneopterin in urine allows for its use as an inflammatory marker. Urinary neopterin and total neopterin provided a fast, non-invasive, and simple measure of oxidative stress and inflammation after knee arthroplasty. 相似文献
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Paul J. Devlin Brian W. McCrindle James K. Kirklin Eugene H. Blackstone William M. DeCampli Christopher A. Caldarone Ali Dodge-Khatami Pirooz Eghtesady James M. Meza Peter J. Gruber Kristine J. Guleserian Bahaaladin Alsoufi Linda M. Lambert James E. OBrien Erle H. Austin Jeffrey P. Jacobs Tara Karamlou 《The Journal of thoracic and cardiovascular surgery》2019,157(2):684-695.e8