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1.
AimsMyocardial strain analysis enables more precise assessment of cardiac performance but is relatively load dependent. New tools have been developed with afterload adjustment. Our objective was to assess myocardial work (MW) in patients with repaired aortic coarctation (rACo).MethodsProspective study of consecutive patients with rACo who underwent a routine transthoracic echocardiogram in 2018 and 2019 at our center. Patients with significant aortic valve disease, pacemaker, or other congenital heart diseases (except for mild bicuspid aortic valve disease) were excluded. Global longitudinal strain with two dimensional speckle tracking analysis and MW were obtained (GWI:Global Work Index; GCW: Global Constructive Work; GWW: Global Wasted Work; GWE: Global Work Efficiency). Blood pressure was measured in the patient's right arm.ResultsWe included 42 patients in the analysis, mean age of 37±10 years, 38% males. In this group, 52% had hypertension and 64% had a concomitant bicuspid aortic valve. In comparison to previously published reference values, patients with rACo had significantly lower GWI (1807 vs. 1896 mmHg%) and GCW (2173 vs. 2232 mmHg%) (p<0.001), particularly in males. Systolic blood pressure is an independent predictor for GWI (β=0.432) and for GCW (β=0.534) and GLS an independent predictor of all MW parameters (β>0.594). Neither age nor gender were independent predictors.ConclusionsIn patients with rACo, there are some signs of left ventricular dysfunction with a reduction in GCW and GWI and with preserved GWE, despite normal ejection fraction and strain.  相似文献   
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目的分析三维斑点追踪成像技术(3D-STI)联合血清同型半胱氨酸(HCY)对冠心病患者左心功能的评估价值。 方法选取2018年5月至2021年6月宣城市人民医院收治的110例冠心病患者,均接受冠状动脉造影术,明确冠状动脉血流情况,根据左旋支、前降支及左冠状动脉单支血管直径狭窄程度分组,将直径狭窄≥50%的单支血管纳入研究组,将直径狭窄<50%的单支血管纳入对照组。比较两组心功能、应变参数、血清HCY,分析左心室应变参数与血清HCY相关性,绘制受试者工作特征(ROC)曲线,分析应变参数与HCY值联合诊断冠心病左心功能的价值。 结果110例冠心病患者均经冠状动脉造影术明确,65例患者单支血管直径狭窄<50%,男性46例,女性19例,年龄(65.41±10.52)岁;45例单支血管直径狭窄≥50%,男性37例,女性8例,年龄(64.83±10.17)岁。研究组A峰高于对照组[(75.58±12.65) cm/s vs(61.02±10.71) cm/s],差异有统计学意义(t=6.506,P<0.001)。研究组左心室短轴缩短率(FS)、左心室射血分数(LVEF)、E峰、E/A值均低于对照组(t=4.616、2.709、2.103、3.896,P均<0.05)。研究组心室整体周向应变(GCS)、整体长轴应变(GLS)、整体径向应变(GRS)、整体面积应变(GAS)均低于对照组(t=8.617、10.535、5.971、6.766,均P<0.001),HCY高于对照组(t=4.915,P<0.001);经Pearson相关系数分析,HCY与GCS、GLS、GRS、GAS呈负相关(r=-0.725、-0.682、-0.762、-0.758,均P<0.001);绘制ROC曲线发现,GCS、GLS、GRS、GAS、HCY及应变参数联合HCY诊断冠心病的曲线下面积(AUC)(95%CI)分别为0.853(0.751~0.954)、0.898(0.802~0.993)、0.731 (0.595~0.868)、0.847(0.735~0.960)、0.863 (0.768~0.957)、0.990(0.973~1.000)。 结论3D-STI应变参数与HCY密切相关,二者联合可有效评估冠心病左心功能。  相似文献   
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Recently, we developed a high-frame-rate echocardiographic imaging system capable of acquiring images at rates up to 2500 per second. High imaging rates were used to quantify longitudinal strain parameters in patients with echocardiographically normal function. These data can serve as a baseline for comparing strain parameters in disease states. The derived timing data also reveal the propagation of mechanical events in the left ventricle throughout the cardiac cycle. High-frame-rate echocardiographic images were acquired from 17 patients in the apical four-chamber view using Duke University's phased array ultrasound system, T5. B-Mode images were acquired at 500–1000 images per second by employing 16:1 or 32:1 parallel processing in receive, a scan depth ≤14 cm and an 80° field of view with a 3.5-MegaHertZ (MHz), 96-element linear array. The images were analyzed using a speckle tracking algorithm tailored for high-frame-rate echocardiographic images developed at Aalborg and Duke University. Four specific mechanical events were defined using strain curves from six regions along the myocardial contour of the left ventricle. The strain curves measure the local deformation events of the myocardium and are independent of the overall cardiac motion. We observed statistically significant differences in the temporal sequence among different myocardial segments for the first mechanical event described, myocardial tissue shortening onset (p < 0.01). We found that the spatial origin of tissue shortening was located near the middle of the interventricular septum in patients with echocardiographically normal function. The quantitative parameters defined here, based on high-speed strain measurements in patients with echocardiographically normal function, can serve as a means of assessing degree of contractile abnormality in the myocardium and enable the identification of contraction propagation. The relative timing pattern among specific events with respect to the Q wave may become an important new metric in assessing cardiac function and may, in turn, improve diagnosis and prognosis.  相似文献   
5.
目的: 探讨超声弹性成像技术在IgG4相关唾液腺炎诊断和随访中的应用价值。方法: 回顾分析2018年5月—10月就诊于上海交通大学医学院附属第九人民医院口腔外科,诊断为IgG4相关唾液腺炎3例患者的临床资料。所有患者均接受口服小剂量糖皮质激素治疗,采用超声弹性成像技术应变率比值法和声辐射力脉冲成像法,对治疗前、后患者下颌下腺进行弹性超声检查,观察超声影像学特点及疗效。结果: 3例患者临床表现均为双侧下颌下腺无痛性肿大超过3个月,血清IgG和IgG4浓度均异常升高,下颌下腺活检病理及免疫组织化学染色结果提示符合IgG4相关唾液腺炎。治疗前弹性超声成像显示腺内大范围蓝色区域对应低回声区,应变率比值(SR)较正常腺体减小而剪切波速值(SWV)较正常腺体增大,表示该区域腺体质地比正常腺体明显较硬。所有患者经小剂量糖皮质激素治疗1个月后随访,临床表现原本肿大的下颌下腺明显消退,触诊质地软化,血清IgG和IgG4浓度明显下降,弹性超声显示蓝色区域范围明显缩小,黄色和绿色区域范围增大,对应SR增大而SWV减小,客观且半量化地反映腺体质地较治疗前软化。结论: 超声弹性成像技术通过测量SR或SWV,可以客观半量化地反映病变唾液腺质地。结合患者的临床表现、血清学指标和组织病理学表现,可以辅助IgG4相关唾液腺炎的诊断,并初步评价疾病的严重性和进展程度。  相似文献   
6.
《Vaccine》2022,40(33):4772-4779
In Portugal, Neisseria meningitidis serogroup B (MenB) is the most common serogroup causing invasive meningococcal disease. To protect against MenB disease two protein based MenB vaccines are available in Portugal, the 4CMenB that was licenced in 2014 and included in the routine immunization program in October 2020, and the bivalent rLP2086 vaccine licensed in 2017. The aim of this study was to predict the coverage of the 4CMenB and rLP2086 vaccines against Portuguese isolates of Neisseria meningitidis sampled between 2012 and 2019 and to evaluate the diversity of vaccine antigens based on genomic analysis.Whole-genome sequence data from 324 Portuguese Neisseria meningitidis isolates were analysed. To predict strain coverage by 4CMenB and rLP2086, vaccine antigen reactivity was assessed using the MenDeVar index available on the PubMLST Neisseria website.This study included 235 (75.6%) MenB isolates of all invasive MenB strains reported between 2012 and 2019. Moreover, 89 non MenB isolates sampled in the same period, enrolling 68 from invasive disease and 21 from healthy carriers, were also studied.The predicted strain coverage of MenB isolates was 73.5% (95% CI: 64.8%–81.2%) for 4CMenB and 100% for rLP2086. Predicted strain coverage by 4CMenB in the age group from 0 to 4 years old, was 73.9%. Most of MenB isolates were covered by a single antigen (85.4%), namely fHbp (30.3%), P1.4 (29.2%), and NHBA (24.7%).In Portugal, the most prevalent peptides in MenB isolates were: P1.4 (16.2%), NHBA peptide 2 (14.0%), and fHbp peptide 14 (7.2%), from 4CMenB and fHbp peptide 19 (10.6%) from rLP2086. No significant temporal trends were observed concerning the distribution and diversity of vaccine antigen variants.4CMenB and rLP2086 vaccines showed potential coverage for isolates regardless serogroup.The use of both vaccines should be considered to control possible outbreaks caused by serogroups with no vaccine available.  相似文献   
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目的:心血管损伤是尿毒症血液透析患者的主要并发症,左房形变与左室充盈压及功能障碍有关,目前量化左房功能仍有一定挑战。本研究探讨四维自动左房定量(LAQ)技术评估保留左室射血分数(LVEF)的尿毒症血液透析患者的左房功能。方法:选取LVEF正常的尿毒症血液透析患者37例和正常对照组34例,所有参与者行常规超声心动图和LAQ检查。主要采集胸骨旁左室长轴和心尖四腔心切面图像,通过脱机分析软件EchoPac 203测量左房直径、容积、射血分数和应变参数,并对两组进行分析比较。结果:与正常对照组相比,尿毒症组的左室扩大、左室壁肥厚,左房直径和容积增加,左房排空分数虽有一定降低,但仍在正常范围内。左房储存、管道及辅泵期的纵向应变均降低,周向应变仅储存和管道期降低,辅泵期无明显差异。结论:尿毒症血液透析患者的心肌损害早于LVEF异常,左房应变比常规超声参数更敏感、更早期发现左房结构和功能的损害。LAQ作为一种新方法,可早期检出LVEF正常的尿毒症患者的左房功能障碍,为临床早期诊疗提供有价值的信息。  相似文献   
9.
目的应用无创左室压力-应变环(PSL)获取接受蒽环类药物化疗的乳腺癌患者左室心肌做功参数,评价蒽环类化疗药物对左室功能的影响。方法选取乳腺癌术后接受蒽环类药物化疗患者30例(乳腺癌组)和正常健康志愿者30例(对照组),乳腺癌组分别于化疗前1 d(T0)及下一周期化疗前1 d(T1、T2、T3、T4、T5)行超声心动图检查。脉冲组织多普勒(PW-TDI)获取二尖瓣环6个位点收缩期峰值运动速度(S’);斑点追踪技术及PSL获取左室整体纵向应变(GLS)、18节段纵向应变达峰时间标准差(Tls-SD)及最大差(Tls-dif)、整体做功指数(GWI)、整体有用功(GCW)、整体无用功(GWW)及整体做功效率(GWE)等参数,比较两组上述参数的差异。结果与对照组比较,乳腺癌组T0期收缩压、舒张压、左室射血分数(LVEF)、Tei指数、二尖瓣环TDI参数、应变参数及心肌做功参数差异均无统计学意义。与T0期比较,乳腺癌组T4、T5期S’-PostSept、S’-Lat、S’-Ant均显著减低(均P<0.05);T1~T5期余常规超声参数均无明显变化。与T0期比较,乳腺癌组T1~T3期GLS无明显变化,T4、T5期GLS均显著减低,且随着化疗周期进展呈递减趋势(均P<0.05);T4、T5期Tls-SD、Tls-dif均显著增大(均P<0.05)。与T0期比较,乳腺癌组T1~T3期GWI、GCW、GWW及GWE均无明显变化;T4、T5期GWI、GCW及GWE均显著减低,且随着化疗周期进展呈递减趋势(均P<0.05);T4、T5期GWW显著增加,且随着化疗周期进展呈递增趋势(均P<0.05)。结论PSL可从心肌做功角度评估接受蒽环类药物化疗的乳腺癌患者化疗早中期左室收缩功能受损,为早期评估乳腺癌化疗相关心功能异常提供新的方法。  相似文献   
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