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31.
BackgroundWhether coronary plaque characteristics assessed in coronary computed tomography angiography (CCTA) in association with the coronary artery calcium score (CACS) have predictive value for coronary events is unclear. We aimed to examine the predictive value of the CACS and plaque characteristics for the occurrence of coronary events.MethodsAmong 2802 patients who were analyzed in the PREDICT registry, 2083 with suspected coronary artery disease (CAD) were studied using post hoc analysis. High-risk plaques were defined as having ≥2 adverse characteristics, such as low computed tomographic attenuation, positive remodeling, spotty calcification, and napkin-ring sign. An adjudicative composite of coronary events (cardiac death, nonfatal acute coronary syndrome, and coronary revascularization ≥3 months after indexed CCTA) were analyzed.ResultsSeventy-three (3.5%) patients had coronary events and 313 (15.0%) had high-risk plaques. Multivariate Cox proportional hazard analysis showed that high-risk plaques remained an independent predictor of coronary events (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.13–3.34, P ?= ?0.0154), as well as the log-transformed CACS (adjusted HR 1.24, 95% CI 1.11–1.39, P ?= ?0.0002) and the presence of obstructive stenosis (adjusted HR 5.63, 95% CI 3.22–10.12, P 0.0001). In subgroup analyses, high-risk plaques were independently predictive only in the low CACS class (<100).ConclusionThis study shows that assessment of adverse features by coronary plaque imaging independently predicts coronary events in patients with suspected CAD and a low CACS. Our findings suggest that the clinical value of high-risk plaques to CACS and stenosis assessment appears marginal.  相似文献   
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目的探讨左心室射血分数(LVEF)减低的左冠状动脉异常起源于肺动脉(ALCAPA)的超声心动图特点及手术效果。 方法选取2008年10月至2018年9月首都医科大学附属北京儿童医院ALCAPA患者28例,根据LVEF分为LVEF减低组(LVEF<50%)19例和LVEF正常组(LVEF≥50%)9例,比较2组患者超声心动图表现,应用两独立样本t检验比较2组患者间超声参数的差异。手术患者(17例)分别于术后1 d、1个月、6个月、1年进行超声心动图随访,应用配对t检验与术前超声参数进行对比。 结果LVEF减低组患者LVEF为30%~48%,平均年龄5.4个月;LVEF正常组LVEF为60%~73%,平均年龄2.5岁。LVEF减低组与LVEF正常组相比,左心室舒张末期内径大[(131.95±24.24)mm/m2 vs(85.67±20.26)mm/m2],右冠状动脉内径小[(3.06±0.51)mm vs(4.01±0.62)mm],差异具有统计学意义(t=-4.465、4.075,P均<0.001),易形成室壁瘤。LVEF减低组中10例行手术治疗,7例超声心动图随访至术后1年;与术前相比,术后1 d开始左心室舒张末期内径逐渐回缩[(109.98±16.06)mm/m2、(99.49±12.02)mm/m2、(89.48±10.90)mm/m2、(80.03±8.09)mm/m2 vs(123.26±12.40)mm/m2],差异具有统计学意义(t=-2.668、-7.519、-5.413、-6.526,P=0.004、0.001、0.012、0.007),LVEF术后1个月开始恢复,术后6个月达正常水平[(45.50±9.57)%、(66.25±10.34)%、(67.25±4.50)% vs(38.83±7.05)%],差异具有统计学意义(t=3.162、3.683、5.869,P=0.025、0.014、0.002)。 结论LVEF减低的ALCAPA患儿年龄小、心脏病变重,超声心动图可以准确作出诊断,但需要与心内膜弹力纤维增生症、扩张型心肌病相鉴别。ALCAPA手术治疗远期效果较好,超声心动图在术后随访中有重要作用。  相似文献   
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Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
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目的 本研究采用二维斑点追踪显像技术(2D-STI)评价使用蒽环类化疗药物患者左室收缩功能及左室收缩同步性,探讨2D-STI在评价蒽环类药物化疗早期心肌毒性中的应用价值。方法 选取我院诊断为乳腺癌的女性患者40例,所有患者均接受表柔比星化疗。分别在化疗前(T0)、第一周期及第二周期化疗后(T1、T2)进行二维超声心动图检查,用EchoPAC软件分析蒽环类药物化疗患者左室心肌内膜、心肌外膜、整体纵向应变(EndoGLS、EpiGLS、GLS)、环向应变(EndoGCS、EpiGCS、GCS)及左室整体径向应变(GRS);获取纵向、环向及径向整体达峰时间标准差(Tssl-SD、Tssc-SD,Tssr-SD)及纵向、环向及径向达峰时间最大差值(Tssl-Dif、Tssc-Dif、Tssr-Dif),获取纵向、环向及径向延迟指数(LSDI、CSDI、RSDI)。结果 与T0周期相比,GLS、endoGLS及endoGCS在T2周期化疗后的变化有统计学意义(p2均<0.05);与T0周期相比,患者Tssl-SD及LSDI 在T2周期化疗后的变化有统计学意义(p2均<0.05)。结论 2D-STI技术获取的分层应变参数及同步性参数可以准确分析蒽环类药物化疗患者早期心肌收缩功能的损伤及室壁运动协调性的损伤,能够敏感发现蒽环类药物化疗后的早期心肌毒性表现。  相似文献   
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IntroductionIn obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA) can lead to gradient reduction and symptom improvement. We aimed to assess the efficacy and safety of ASA in a long-term outcome study.MethodsWe analyzed patients who underwent ASA over a seven-year period in a tertiary center. The primary echocardiographic endpoint was >50% reduction in left ventricular outflow tract (LVOT) gradient within a year of the procedure. The primary clinical endpoints were improvement in functional capacity and a combined endpoint of cardiac death and rehospitalization for cardiac cause. The follow-up period was 4.17±2.13 years.ResultsA total of 80 patients, mean age 63.9±12.3 years, 30.0% male, were analyzed. Baseline LVOT gradient was 96.3±34.6 mmHg and interventricular septal thickness was 21.6±3.1 mm. Minor complications were observed in 6.3% and major complications in 2.5%, and 8.8% received a permanent pacemaker.The primary echocardiographic endpoint was achieved by 85.7%. At three-month follow-up, LVOT gradient was 25.8±26.0 mmHg in the successful procedure group, compared to 69.2±35.6 mmHg in the other patients (p=0.001). At six months, LVOT gradient was 27.1±27.4 vs. 58.2±16.6 mmHg (p=0.024). Among 74 patients in NYHA class III/IV before the procedure, 57 (77%) improved to NHYA class I/II. The combined primary clinical endpoint (cardiac death and rehospitalization for cardiac cause) was observed in 27.5% (n=22). In the unsuccessful group, the combined endpoint was observed in 54.5%, compared to only 22.7% in the successful group. Only two patients died of cardiac causes.ConclusionASA is a safe procedure with a high success rate. Patients who achieved significant reductions in LVOT gradient suffered less cardiac death and rehospitalization for cardiac cause.  相似文献   
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目的探讨左心室舒张功能减低与青年高血压病患者急性脑梗死的相关性。方法收集2014年10月~2018年2月宝鸡市第二中医医院神经内科收治的青年急性脑梗死同时患有高血压病的患者92例(观察组),同时选取同期患有高血压病的青年体检患者98例(对照组)。对两组患者都进行心脏彩色多普勒检查,观察患者的左心室舒张功能,并分析左心室舒张功能减低与急性脑梗死的关系。结果 190例青年高血压病患者中,左心室舒张功能正常者18例,占9. 47%,左心室舒张功能减低者172例,占90. 53%,其中127例为左心室舒张功能减低1级,占66. 84%(127/190),55例为左心室舒张功能2级,占28. 95%(55/190),8例为左心室舒张功能3级,占4. 21%(8/190)。观察组患者IVRT、Ea/Aa及A’值分别为(114. 97±10. 16)、(0. 79±0. 11)和(5. 21±1. 03),对照组分别为(72. 86±8. 75)、(1. 3±0. 25)和(5. 02±0. 82),差异有统计学意义(P 0. 05)。观察组患者左心室舒张功能减低IVRT、Ea/Aa及A’值和急性脑梗死发生之间有相关关系(r=0. 53,r=0. 61,r=-0. 59)。结论青年左心室舒张功能减低与高血压病有关,左室舒张功能减低可能是青年高血压病患者罹患急性脑梗死的独立预测因素。  相似文献   
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