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991.
Christina Maria Steger Tobias Mayr Nikolaos Bonaros Johannes Bonatti Thomas Schachner 《International journal of experimental pathology》2016,97(6):447-456
A major reason for vein graft failure after coronary artery bypass grafting is neointimal hyperplasia and thrombosis. Elevated serum levels of homocysteine (Hcy) are associated with higher incidence of cardiovascular disease, but homocysteine levels also tend to increase during the first weeks or months after cardiac surgery. To investigate this further, C57BL/6J mice (WT) and cystathionine‐beta‐synthase heterozygous knockout mice (CBS+/?), a mouse model for hyperhomocysteinaemia, underwent interposition of the vena cava of donor mice into the carotid artery of recipient mice. Two experimental groups were examined: 20 mice of each group underwent bypass surgery (group 1: WT donor and WT recipient; group 2: CBS+/? donor and CBS+/? recipient). After 4 weeks, the veins were harvested, dehydrated, paraffin‐embedded, stained and analysed by histomorphology and immunohistochemistry. Additionally, serum Hcy levels in CBS knockout animals and in WT animals before and after bypass surgery were measured. At 4 weeks postoperatively, group 2 mice showed a higher percentage of thrombosis compared to controls, a threefold increase in neointima formation, higher general vascularization, a lower percentage of elastic fibres with shortage and fragmentation in the neointima, a lower percentage of acid mucopolysaccharides in the neointima and a more intense fibrosis in the neointima and media. In conclusion, hyperhomocysteinaemic cystathionine‐beta‐synthase knockout mice can play an important role in the study of mechanisms of vein graft failure. But further in vitro and in vivo studies are necessary to answer the question whether or not homocysteine itself or a related metabolic factor is the key aetiologic agent for accelerated vein graft disease. 相似文献
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994.
《Journal of Cardiovascular Computed Tomography》2019,13(1):62-67
BackgroundCTA based FFR, a software based application, enhances diagnostic value of coronary computed tomography angiography (CTA) examination. However it remains unknown whether it improves accuracy over the gold standard of invasive coronary angiography (ICA) in predicting functionally significant coronary stenosis. The aim of our study was to compare diagnostic accuracies of coronary CTA, CTA based FFR, and ICA, with invasive FFR as the reference standard in patients with intermediate stenosis on CTA.Methods96 intermediate stenoses (50–90%) from 90 subjects, with intermediate pre-test probability of CAD, who underwent coronary CTA were analyzed. Each patient had subsequent ICA with FFR. CTA based FFR (cFFR v2.1, Siemens) analysis was performed on-site. The stenoses with invasive FFR≤0.8 were considered hemodynamically significant.Results41/96 stenoses were hemodynamically significant (FFR≤0.8). While the area under ROC curves (AUC) for identification of significant stenosis evaluated on QCA (0.653), visual ICA (0.652), qCTA (0.690) and visual CTA (0.660) did not significantly differ, the AUC for CTA based FFR (0.835) was significantly higher (p = 0.004, p = 0.004, p = 0.010, p = 0.007, respectively). The accuracies of CTA based FFR, qCTA and QCA were 76%, 63% and 58% respectively.ConclusionOur results suggest that diagnostic potential of routine coronary CTA, augmented with CTA based FFR analysis, is superior to ICA in patients with intermediate stenosis. 相似文献
995.
《Journal of vascular and interventional radiology : JVIR》2019,30(6):922-927
PurposeTo generate 3-dimensional (3D) printed ultrasound (US)-compatible vascular models (3DPVAM) and test them for noninferiority in training medical students in femoral artery access.Materials and MethodsA 3DPVAM of normal femoral artery (FA) anatomy was developed from an anonymized computerized tomography (CT) examination. Students were randomized to a 3DPVAM or a commercial model (CM) simulation experience (SE) for US-guided FA access. Students completed a pre-SE questionnaire ranking their self-confidence in accessing the artery on a 5-point Likert scale. A standardized SE was administered by interventional radiology faculty or trainees. Students completed a post-SE questionnaire ranking comfort with FA access on a Likert scale. Student questionnaire results from the 3DPVAM group were compared with those from the CM group by using chi-square, Wilcoxon signed-rank, and noninferiority analyses.ResultsTwenty-six and twenty-three students were randomized to 3DPVAM and commercial model training, respectively. A total of 76.9% of 3DPVAM trainees and 82.6% of CM trainees did not feel confident performing FA access prior to the SE. In both groups, training increased student confidence by 2 Likert points (3DPVAM: P < 0.001; CM P < 0.001). The confidence increase in 3DPVAM trainees was noninferior to that in CM trainees (P < 0.001).ConclusionsGeneration of a custom-made 3DPVAM is feasible, producing comparable subjective training outcomes to those of CM. Custom-made 3D-printed training models, including incorporation of more complex anatomical configurations, could be used to instruct medical students in procedural skills. 相似文献
996.
Varun Aggarwal Sebastian C. Tume Marco Rodriguez Iki Adachi Antonio G. Cabrera Hari Tunuguntla Athar M. Qureshi 《Congenital heart disease》2019,14(6):1130-1137
Objective: Predictors of right ventricle (RV) dysfunction after continuous‐flow left
ventricular assist device (CF‐LVAD) implantation in children are not well described.
We explored the association of preimplantation Pulmonary Artery Pulsatility index
(PAPi) and other hemodynamic parameters as predictors of prolonged postoperative
inotropes/pulmonary vasodilator use after CF‐LVAD implantation.
Design: Retrospective chart review.
Setting: Single tertiary care pediatric referral center.
Patients: Patients who underwent CF‐LVAD implantation from January 2012 to October 2017.
Interventions: Preimplantation invasive hemodynamic parameters were analyzed to evaluate the association with post‐CF‐LVAD need for prolonged (>72 hours) use of inotropes/pulmonary vasodilators.
Measurements and main results: Preimplantation cardiac catheterization data was available for 12 of 44 patients who underwent CF‐LVAD implant during the study period. Median (IQR) age and BSA of the cohort were 15.3 years (10.2, 18) and 1.74 m2 (0.98, 2.03). Group 1 (n = 6) included patients with need for prolonged inotropes/pulmonary vasodilator use after CF‐LVAD implantation and Group 2 (n = 6) included those without. Baseline demographic parameters, cardiopulmonary bypass time, and markers of RV afterload (pulmonary vascular resistance, PA compliance and elastance) were similar among the two groups. PAPi was significantly lower in group 1 compared to group 2 (0.96 vs 3.6, respectively; P = .004). Post‐LVAD stay in the intensive care unit was longer for patients in group 1 (46 vs 23 days, P = .52). Brain natriuretic peptide was significantly higher at 3 months after implantation in group 1; P = .01.
Conclusions: The need for inotropes/pulmonary vasodilators in the postoperative period can be predicted by the preimplantation intrinsic RV contractile reserve as assessed by PAPi rather than the markers of RV afterload. Further investigation and correlation with clinical outcomes is needed. 相似文献
Design: Retrospective chart review.
Setting: Single tertiary care pediatric referral center.
Patients: Patients who underwent CF‐LVAD implantation from January 2012 to October 2017.
Interventions: Preimplantation invasive hemodynamic parameters were analyzed to evaluate the association with post‐CF‐LVAD need for prolonged (>72 hours) use of inotropes/pulmonary vasodilators.
Measurements and main results: Preimplantation cardiac catheterization data was available for 12 of 44 patients who underwent CF‐LVAD implant during the study period. Median (IQR) age and BSA of the cohort were 15.3 years (10.2, 18) and 1.74 m2 (0.98, 2.03). Group 1 (n = 6) included patients with need for prolonged inotropes/pulmonary vasodilator use after CF‐LVAD implantation and Group 2 (n = 6) included those without. Baseline demographic parameters, cardiopulmonary bypass time, and markers of RV afterload (pulmonary vascular resistance, PA compliance and elastance) were similar among the two groups. PAPi was significantly lower in group 1 compared to group 2 (0.96 vs 3.6, respectively; P = .004). Post‐LVAD stay in the intensive care unit was longer for patients in group 1 (46 vs 23 days, P = .52). Brain natriuretic peptide was significantly higher at 3 months after implantation in group 1; P = .01.
Conclusions: The need for inotropes/pulmonary vasodilators in the postoperative period can be predicted by the preimplantation intrinsic RV contractile reserve as assessed by PAPi rather than the markers of RV afterload. Further investigation and correlation with clinical outcomes is needed. 相似文献
997.
B. Kowall N. Lehmann A.A. Mahabadi S. Moebus R. Erbel K.H. Jöckel A. Stang 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(3):228-235
Background and aims
There is controversy on the potentially benign nature of metabolically healthy obesity (MHO), i.e., obese persons with few or no metabolic abnormalities. So far, associations between MHO and coronary artery calcification (CAC), a measure of subclinical atherosclerosis, have mainly been studied cross-sectionally in Asian populations. We assessed cross-sectional and longitudinal MHO CAC associations in a Caucasian population.Methods and results
In the Heinz Nixdorf Recall Study, a population-based cohort study in Germany, CAC was assessed by electron-beam tomography at baseline and at 5-year follow-up. For cross-sectional and longitudinal analyses, we included 1585 participants free of coronary heart disease at baseline, with CAC measurements at baseline and at follow-up, and with either normal weight (BMI 18.5–24.9 kg/m2) or obesity (BMI ≥30.0 kg/m2) at baseline. We used four definitions of MHO. In our main analysis, we defined obese persons as metabolically healthy if they met ≤1 of the NCEP ATP III criteria for the definition of the metabolic syndrome – waist circumference was not taken into account because of collinearity with BMI.Persons with MHO had a higher prevalence of CAC than metabolically healthy normal weight (MHNW) persons (prevalence ratio = 1.59 (95% confidence interval 1.38–1.84) for the main analysis). Persons with MHO had slightly larger odds of CAC progression than persons with MHNW (odds ratios ranged from 1.17 (0.69–1.99) to 1.48 (1.02–2.13) depending on MHO definition and statistical approach).Conclusion
Our analyses on MHO CAC associations add to the evidence that MHO is not a purely benign health condition. 相似文献998.
James L. Januzzi Sunil Suchindran Udo Hoffmann Manesh R. Patel Maros Ferencik Adrian Coles Jean-Claude Tardif Geoffrey S. Ginsburg Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(3):251-260
Background
Evaluation of stable symptomatic outpatients with suspected coronary artery disease (CAD) may be challenging because they have a wide range of cardiovascular risk. The role of troponin testing to assist clinical decision making in this setting is unexplored.Objectives
This study sought to evaluate the prognostic meaning of single-molecule counting high-sensitivity troponin I (hsTnI) (normal range <6 ng/l) among outpatients with stable chest symptoms and suspected CAD.Methods
Participants with available blood samples in PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) were studied, and hsTnI results were analyzed relative to the primary outcome of death, acute myocardial infarction (MI), or hospitalization for unstable angina by 1 year. The secondary outcome was the composite of cardiovascular death or acute MI.Results
The study sample consisted of 4,021 participants; 98.6% had measurable hsTnI concentrations. The median hsTnI value was 1.6 ng/l. In upper hsTnI quartiles, patients had higher-risk clinical profiles. Higher hsTnI concentrations were associated with greater event probabilities for death, acute MI, or hospitalization for unstable angina. In multivariable models, hsTnI concentrations independently predicted death, acute MI, or hospitalization for unstable angina (hazard ratio: 1.54 per increase in log-hsTnI interquartile range; p < 0.001) and cardiovascular death or acute MI (hazard ratio: 1.52 per increase in log-hsTnI interquartile range; p < 0.001) and were particularly associated with near-term events, compared with longer follow-up.Conclusions
In symptomatic outpatients with suspected CAD, higher concentrations of hsTnI within the normal range were associated with heightened near-term risk for death, acute MI, or hospitalization. (Prospective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献999.
1000.