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61.
62.

Background

Isolated tricuspid valve replacement is rare when performed as a re-operation after a left side operation. It is important to know the factors that determine mortality and morbidity. Tricuspid Annular Plane Systolic Excursion (TAPSE) is a scoring system that is used with non-invasive Doppler echocardiography to determine right ventricular (RV) function. This study analyzed TAPSE scores and adverse outcomes of isolated tricuspid valve surgery in patients with previous cardiac surgery.

Methods

All patients who underwent tricuspid valve replacement between January 2014 and December 2015 were retrospectively reviewed. Patients having concomitant mitral or aortic valve surgery were excluded. These patients were divided into two groups: TAPSE >14 mm and TAPSE ≤14 mm. In-hospital outcomes were compared.

Results

A total of 26 patients with severe tricuspid valve regurgitation underwent tricuspid valve replacement. There were 5 males (19.2%) and 21 females (80.8%). The average age at operation was 54.77±9.61 years (range, 27–69 years). There were 16 patients in the TAPSE >14 mm group and 10 patients in the TAPSE ≤14 mm group. The BNP in the TAPSE >14 mm group was significant (TAPSE >14 mm 672.34±229.98 versus TAPSE ≤14 mm 1,054.79±684.69, P=0.03). The median cardiopulmonary bypass (CPB) time and red blood cell (RBC) transfusions in the two groups were not different. The need for prolonged ventilatory support (>48 h) in the two groups was also not different (TAPSE> 14 mm 91.2±12.31 vs. TAPSE ≤14 mm 39.00±36.80, P=0.46). Moreover, hospital stays were similar between the two groups. No differences were found in postoperative renal and respiratory complications.

Conclusions

It is important to determine the right ventricule function quantitatively. The TAPSE score is an important parameter that determines the cardiac index and right ventricle function. It should be used for the prediction of mortality and morbidity with all the other parameters as a whole.  相似文献   
63.
目的评价超声引导下腹横肌平面阻滞(TAPB)对于妇科腹腔镜手术患者预防性镇痛的效果。方法选取拟在全麻下行妇科腹腔镜手术患者60例,既往无其他特殊病史,美国麻醉医师协会(ASA)分级Ⅰ或Ⅱ级,年龄30~50岁,体重50~65 kg。采用随机数字表法,将其分为3组(n=20):对照组(Ⅰ组)、术前TAPB组(Ⅱ组)和术后TAPB组(Ⅲ组)。Ⅰ组不实施神经阻滞,Ⅱ组和Ⅲ组分别于麻醉诱导前或手术结束后行超声引导下双侧TAPB术。术后3组患者均采用1μg/ml舒芬太尼静脉自控镇痛(PCIA),背景输注速率2 ml/h,患者自控镇痛(PCA)剂量2 ml,锁定时间15 min,持续至术后第2天,维持疼痛视觉模拟(VAS)评分≤3分,若VAS评分3分时,静脉注射氟比洛芬酯50 mg行镇痛补救。记录术后24 h内舒芬太尼单位时间内用量、镇痛补救情况和不良反应的发生情况,计算舒芬太尼节俭程度。结果与Ⅰ组比较,Ⅱ组和Ⅲ组术后24 h内舒芬太尼单位时间内用量、镇痛补救率和恶心呕吐的发生率降低(P0.05);与Ⅲ组比较,Ⅱ组术后24 h内舒芬太尼单位时间内用量、镇痛补救率及恶心呕吐的发生率降低(P0.05)。Ⅱ组较Ⅰ组舒芬太尼用量节俭35.0%,较Ⅲ组舒芬太尼用量节俭16.0%。结论超声引导下TAPB能为妇科腹腔镜手术患者提供良好的术后镇痛,术前行神经阻滞效果优于术后。  相似文献   
64.
目的:分析经自动乳腺全容积成像(ABVS)所获得的乳腺癌图像冠状面特征与分子分型之间的联系。 方法:对153例(157个病灶)经病理证实的乳腺癌患者的ABVS冠状面图像特征及免疫组化结果进行回顾性分析,探讨乳腺癌ABVS冠状面图像特征与分子分型的相关性。 结果:不同分子分型的乳腺癌在ABVS冠状面上显示的边界、微钙化及间接征象方面均有统计学差异(P<0.05),微钙化在Luminal B型和Her-2过表达型中占比例较多(69.4%、77.3%),汇聚征在Luminal A型最常见(43.7%),三阴型更容易出现清晰的边界(27.8%)。四种分子分型的组织病理学特征及边缘形态之间的差异无统计学意义(P>0.05)。 结论:乳腺癌ABVS图像冠状面特征与四种亚型之间有一定的相关性。  相似文献   
65.
66.
《JACC: Cardiovascular Imaging》2019,12(12):2373-2385
ObjectivesThis study sought to compare the prognostic value of 2-dimensional (2D) right ventricular (RV) speckle tracking (STE) against cardiac magnetic resonance (CMR) RV ejection fraction (EF) and feature tracking (FT) and conventional echocardiographic parameters on overall and cardiovascular (CV) survival in patients with heart failure with reduced EF (HFrEF).BackgroundPrior works showed that RV systolic function predicts prognosis in HFrEF. 2D RVSTE had recently been proposed as new echocardiographic method to evaluate RV dysfunction.MethodsA total of 266 patients with HFrEF (mean LVEF 23 ± 7%, 60 ± 14 years of age; 29% women) underwent RV function assessment using CMR and 2D echocardiography and were followed for a primary endpoint of overall death and secondary endpoint of CV death.ResultsAverage CMR-RVEF was 42 ± 15%, average STE RV global longitudinal strain (STE-RVGLS) was −18.0 ± 4.9%, and average CMR-FT-RVGLS was −11.8 ± 4.3%. After a median follow-up of 4.7 years, 102 patients died, 84 of a CV cause. RVEF, FT-RVGLS, tricuspid annulus plane systolic excursion (TAPSE), fractional area change (FAC), and STE-RVGLS were significant univariate predictors of overall and cardiac death. In multivariate Cox regression, age, ischemic etiology, diabetes, New York Heart Association functional class III to IV, and beta-blocker treatment were independent clinical predictors of overall mortality. CMR-RVEF (chi-square to enter = 3.9; p < 0.05), FT-RVGLS (chi-square to enter 3.7; p = 0.05), FAC (chi-square to enter 6.2; p = 0.02), and TAPSE (chi-square to enter = 4.1; p = 0.04) provided additional prognostic value over these baseline parameters, but the additional predictive value of STE-RVGLS (chi-square to enter = 10.8; p < 0.001) was significantly (p < 0.05) higher than the other tests. Additional hazard ratio to predict overall mortality was 2.5 (95% confidence interval [CI]: 1.6 to 3.9) for STE-RVGLS <−19%, 2.15 (95% CI: 1.34 to 3.43) for TAPSE >15 mm, 1.6 (95% CI: 1.02 to 2.49) for FAC >39%, 1.93 (95% CI: 1.25 to 2.99) for RVEF >41%, and 1.87 (95% CI: 1.10 to 3.19) for CMR-FT-RVGLS <−15%.Conclusions2D RVGLS provides strong additional prognostic value to predict overall and CV mortality in HFrEF, with higher predictive value than CMR-RVEF, CMR-FT-RVGLS, TAPSE, or FAC. This supports use of STE-RVGLS to identify higher-risk HFrEF patients.  相似文献   
67.
ObjectivesThe aim of this study was to characterize left atrial (LA) pathology in explanted hearts with transthyretin amyloid cardiomyopathy (ATTR-CM); LA mechanics using echocardiographic speckle-tracking in a large cohort of patients with ATTR-CM; and to study the association with mortality.BackgroundThe clinical significance of LA involvement in ATTR-CM is of great clinical interest.MethodsCongo red staining and immunohistochemistry was performed to assess the presence, type, and extent of amyloid and associated changes in 5 explanted ATTR-CM atria. Echo speckle tracking was used to assess LA reservoir, conduit, contractile function, and stiffness in 906 patients with ATTR-CM (551 wild-type (wt)-ATTR-CM; 93 T60A-ATTR-CM; 241 V122I-ATTR-CM; 21 other).ResultsThere was extensive ATTR amyloid infiltration in the 5 atria, with loss of normal architecture, vessels remodeling, capillary disruption, and subendocardial fibrosis. Echo speckle tracking in 906 patients with ATTR-CM demonstrated increased atrial stiffness (median [25th-75th quartile] 1.83 [1.15-2.92]) that remained independently associated with prognosis after adjusting for known predictors (lnLA stiff: HR: 1.23; 95% CI: 1.03-1.49; P = 0.029). There was substantial impairment of the 3 phasic functional atrial components (reservoir 8.86% [5.94%-12.97%]; conduit 6.5% [4.53%-9.28%]; contraction function 4.0% [2.29%-6.56%]). Atrial contraction was absent in 22.1% of patients whose electrocardiograms showed sinus rhythm (SR) “atrial electromechanical dissociation” (AEMD). AEMD was associated with poorer prognosis compared with patients with SR and effective mechanical contraction (P = 0.0018). AEMD conferred a similar prognosis to patients in atrial fibrillation.ConclusionsThe phenotype of ATTR-CM includes significant infiltration of the atrial walls, with progressive loss of atrial function and increased stiffness, which is a strong independent predictor of mortality. AEMD emerged as a distinctive phenotype identifying patients in SR with poor prognosis.  相似文献   
68.
The close agreement between biplane (BP) and single-plane (SP) angiographic estimates of left ventricular (LV) volumes results from the similarity of the minor axes measured in the right anterior oblique (RAO) and left anterior oblique (LAO) views. Disease states that alter LV geometry may change the length of one minor axis more than the other, producing a discrepancy between BP and SP volumes. To examine this hyposthesis, angiographically derived volumes in 21 patients with atrial septal defects (ASD) in which the LV appears to be compressed and flattened by an enlarged right ventricle, were compared to 100 normal control patients. In the control patients, the median SP estimate of end-diastolic volume (EDV) was 7.6% larger than the BP determination, whereas in patients with ASD, the median SP EDV estimate was 16.7% larger than the BP EDV (P<0.0001). The SP end-systolic volume (ESV) underestimated the BP value by 3.4% in controls but overestimated the BP ESV in patients with ASD by 4.3% (P<0.02). The overestimate of the SP EDV and SP ESV when compared to the BP volumes may be due to changes in either the minor axes or the appearance of the longest major axis in the LAO view. The longest major axis was found in the RAO view in 99% (99/100) of normals and 95% (20/21) of ASD patients (P?NS). The median ratio of RAO to LAO end-diastolic minor axes, however, was 1.07 in the normals and 1.17 for ASD patients. The median ratio of end-systolic minor axes was 0.97 for controls and 1.04 for ASD patients. Compression of the LV in patients with ASD shortens the LAO minor axis, resulting in a significantly greater SP overestimation of LV volume than occurs in normals. The degree of SP volume overestimate was not predicted by the magnitude of the left-to-right shunt or pulmonary pressure. This source of error affects all SP methods for determining left ventricular volume, including radionuclide techniques using static images.  相似文献   
69.
Three-dimensional assessment of optically cleared, entire organs and organisms has recently become possible by tissue clearing and selective plane illumination microscopy (“ultramicroscopy”). Resulting datasets can be highly complex, encompass over a thousand images with millions of objects and data of several gigabytes per acquisition. This constitutes a major challenge for quantitative analysis. We have developed post-processing tools to quantify millions of microvessels and their distribution in three-dimensional datasets from ultramicroscopy and demonstrate the capabilities of our pipeline within entire mouse brains and embryos. Using our developed acquisition, segmentation, and analysis platform, we quantify physiological vascular networks in development and the healthy brain. We compare various geometric vessel parameters (e.g. vessel density, radius, tortuosity) in the embryonic spinal cord and brain as well as in different brain regions (basal ganglia, corpus callosum, cortex). White matter tract structures (corpus callosum, spinal cord) showed lower microvascular branch densities and longer vessel branch length compared to grey matter (cortex, basal ganglia). Furthermore, we assess tumor neoangiogenesis in a mouse glioma model to compare tumor core and tumor border. The developed methodology allows rapid quantification of three-dimensional datasets by semi-automated segmentation of fluorescently labeled objects with conventional computer hardware. Our approach can aid preclinical investigations and paves the way towards “quantitative ultramicroscopy”.  相似文献   
70.
BackgroundIncreasing the ankle plantar-flexion angle at initial contact (IC) during landing reduces the impact features associated with landing, such as the vertical ground reaction force and loading rate, potentially affecting the risk of anterior cruciate ligament (ACL) injury. However, the relationships between the ankle plantar-flexion angle at IC and the previously identified biomechanical factors related to noncontact ACL injury have not been studied.Research questionThus, the purpose of this study was to determine whether significant relationships exist between the ankle plantar-flexion angle at IC and the biomechanical factors related to noncontact ACL injury.MethodsThe peak anterior tibial shear force, peak external knee valgus moment, peak knee valgus angle, and combined peak external knee valgus plus tibial internal rotation moments were measured in 26 individuals while performing self-selected, single-leg landing. Pearson correlation analyses were performed to assess the relationships between the ankle plantar-flexion angle at IC and the biomechanical factors mentioned above.ResultsThe greater ankle plantar-flexion angle at IC was related to smaller the peak knee valgus moment (r = −0.5, p = 0.009) and the combined peak knee valgus plus internal rotation moments (r = −0.58, p = 0.001).SignificanceThese results suggest that large ankle plantar-flexion angle at IC might be associated with lesser loading of the knee frontal plane and altering the self-selective ankle angle may result in biomechanical changes associated with ACL injury risk.  相似文献   
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