主动脉出口血压对左心室血流特性的影响

采用Mimics对心脏进行三维重构，用3-matic进行模型优化以及模型误差分析，对左心室室壁运动做速度分布假设，基于UDF宏文件对左心室室壁运动编写程序，将血液视为非牛顿流体，采用动网格技术研究不同血压对左心室血液流动的影响。模拟发现当左心室收缩时，压力梯度明显，内部压力减小。当左心室舒张时，内部压力逐渐增高。二尖瓣口处的速率先增大后减小。血压升高，左心室内剪切应力持续增大，极易破坏红细胞结构，产生溶血现象，导致心脏功能紊乱。     

Quantification of myocardial fibrosis using noninvasive T2-mapping magnetic resonance imaging: Preclinical models of aging and pressure overload

Noninvasive imaging of cardiac fibrosis is important for early diagnosis and intervention in chronic heart diseases. Here, we investigated whether noninvasive, contrast agent-free MRI T₂-mapping can quantify myocardial fibrosis in preclinical models of aging and pressure overload. Myocardial fibrosis and remodeling were analyzed in two animal models: (i) aging (15-month-old male CF-1 mice vs. young 6- to 8-week-old mice), and (ii) pressure overload (PO; by transverse aortic constriction in 4- to 5-month-old male C57BL/6 mice vs. sham-operated for 14 days). In vivo T₂-mapping was performed by acquiring data during the isovolumic and early diastolic phases, with a modified respiratory and ECG-triggered multiecho TurboRARE sequence on a 7-T MRI. Cine MRI provided cardiac morphology and function. A quantitative segmentation method was developed to analyze the in vivo T₂-maps of hearts at midventricle, apex, and basal regions. The cardiac fibrosis area was analyzed ex vivo by picro sirius red (PSR) staining. Both aged and pressure-overloaded hearts developed significant myocardial contractile dysfunction, cardiac hypertrophy, and interstitial fibrosis. The aged mice had two phenotypes, fibrotic and mild-fibrotic. Notably, the aged fibrotic subgroup and the PO mice showed a marked decrease in T₂ relaxation times (25.3 ± 0.6 in aged vs. 29.9 ± 0.7 ms in young mice, p = 0.002; and 24.3 ± 1.7 in PO vs. 28.7 ± 0.7 ms in shams, p = 0.05). However, no significant difference in T₂ was detected between the aged mild-fibrotic subgroup and the young mice. Accordingly, an inverse correlation between myocardial fibrosis percentage (FP) and T₂ relaxation time was derived (R² = 0.98): T₂ (ms) = 30.45 – 1.05 × FP. Thus, these results demonstrate a statistical agreement between T₂-map–quantified fibrosis and PSR staining in two different clinically relevant animal models. In conclusion, T₂-mapping MRI is a promising noninvasive contrast agent-free quantitative technique to characterize myocardial fibrosis.     

Midterm Outcomes of Angioplasty for Pediatric Renovascular Hypertension

PurposeTo evaluate the midterm outcomes of percutaneous transluminal renal angioplasty (PTRA) for pediatric renovascular hypertension (RVH).Materials and MethodsThe clinical data of patients who underwent PTRA for RVH in the authors’ hospital from 2012 to 2019 were retrospectively analyzed. Postprocedural blood pressure, glomerular filtration rate (GFR) of the affected kidney, restenosis, and complications were closely monitored.ResultsPTRA was performed in a total of 30 children (20 boys and 10 girls), with a mean age of 7.3 years ± 0.7 (range, 40 days to 13.9 years) and a mean weight of 25.0 kg ± 2.3 (range, 3.4–53 kg). The median follow-up period was 26.5 months (range, 1 month to 7.5 years). Technical success was achieved in 26 (86.7%) of the 30 patients. Restenosis developed in 3 patients (10.0%). Only 1 patient underwent stent implantation, and the stent fractured 8 months later, requiring further intervention. There were no other complications. In terms of clinical benefit of blood pressure control after the initial PTRA procedure, 15 patients (50%) were cured and 7 patients (23.3%) showed improvement. There was no significant difference in the etiology, lesion location, and lesion length between patients with clinical benefit and failure (P = .06, P = .202, and P = .06, respectively). GFR of the affected kidney was significantly improved from 19.9 mL/min ± 11.2 to 38.1 mL/min ± 11.9 at the 6-month follow-up after PTRA (P < .001).ConclusionsThe overall results of PTRA for pediatric RVH caused by different etiologies are promising. PTRA not only provided a clinical benefit of blood pressure control in 73.3% of the patients but also significantly improved the function of the affected kidney.     

血府逐瘀汤合温胆汤加减联合西药治疗高血压颈动脉硬化的临床观察

目的:观察血府逐瘀汤合温胆汤加减联合西药治疗高血压颈动脉硬化的效果。方法:选取2017年6月至2018年6月聊城市中医院收治的高血压颈动脉硬化患者92例作为研究对象,按照随机数字表法随机分为对照组与观察组,每组46例。对照组患者给予左旋氨氯地平+阿托伐他汀口服,观察组在对照组基础上加用血府逐瘀汤合温胆汤加减口服。观察患者血压、血脂控制情况,测定颈动脉内膜中层厚度(IMT)、斑块面积、血管皮内皮功能、血清蛋白酶分子水平。结果:与对照组比较,观察组治疗后的血压SBP、DBP及血脂TG、TC、LDL-C等指标更低(P<0.05);颈动脉粥样硬化斑块IMT厚度、斑块面积明显缩小(P<0.05),血管内皮功能指标ET-1、AngⅡ、TXB2水平明显降低,NO水平明显升高(P<0.05);血清CatK、MMP-9水平明显降低(P<0.05);观察组不良反应发生率8.70%明显低于对照组不良反应发生率21.74%(P<0.05)。结论:血府逐瘀汤合温胆汤加减联合西药更利于控制高血压颈动脉硬化患者的血压,调节脂质代谢,改善血管内皮功能,降低血清蛋白酶分子的含量,用药安全。     

李延应用泽泻汤合温胆汤治疗舒张压高的临床经验

随着社会的发展,人类生活方式的改变,高血压病越来越高发,具有低龄化趋势,代谢综合征常伴随发生,此种情况下的高血压往往是以舒张压升高为主,临床表现常与“亚健康”状态混淆,未能引起患者甚至部分医生的重视,然而事实上越来越多的科学研究证实舒张压高之危害十分明显,不容忽视。尽管现代医学对舒张压高的病因及病理机制有明确的阐述,但是暂时没有特效的药物。李延教授在治疗高血压病方面有着丰富的临床经验,临床中运用泽泻汤合温胆汤加减治疗舒张压高之眩晕,切中病机,加减灵活,屡有良效。文中从中医角度阐述舒张压高的病因病机,介绍李师辨病辨证思路,组方用药特点,附三则典型验案,另加个人心得体会,以期为舒张压高的有效治疗提供思路。     

Ventilatory support in the intensive care unit

This article focuses on the functional features of positive-pressure ventilators, the modes of invasive and non-invasive mechanical ventilation, and the main ventilator settings. It also highlights the potential complications of mechanical ventilation, the basic principles of weaning, and the pathophysiological basis of patient-ventilator dyssynchrony.     

右美托咪啶与芬太尼联合对ICU 腹部外科术后机械通气患者镇静镇痛的效果比较

目的:探讨右美托咪啶与芬太尼联合在ICU腹部外科术后机械通气患者中的应用效果及对镇静、镇痛作用的影响。方法:选择2018年5月—2019年6月ICU腹部外科术后机械通气患者62例,随机分为对照组(n=31例)和观察组(n=31例)。两组均采用芬太尼持续静脉泵入,对照组采用咪达唑仑镇静镇痛,观察组采用右美托咪啶镇静镇痛,比较两组镇痛镇静效果、镇静剂使用剂量、苏醒及达到镇静所需时间、血流动力学水平及安全性。结果:两组T2、T3时间点VAS评分分别为(2.40±0.31 vs 2.43±0.32和2.01±0.12 vs 2.05±0.15)、Ramsay量表评分分别(3.21±0.35 vs 3.20±0.33和3.01±0.25vs 3.00±0.24)均低于T1时间点(VAS评分2.94±0.69 vs 2.96±0.71;Ramsay量表评分3.57±0.61 vs 3.58±0.62)(P0.05);观察组右美托咪啶联合芬太尼镇痛镇静达到镇静所需时间(34.29±3.56) min长于对照组(23.63±3.21)(t=5.535,P=0.043);观察组镇静剂使用剂量(220.59±15.25)μg、苏醒时间(3.29±0.69)min均少(短)于对照组镇静剂使用剂量(386.44±18.92)μg、苏醒时间(7.56±1.21)min(t=6.294、6.092,P=0.023、0.025);两组T1、T2时间点心率[观察组T1(88.47±9.76)次/min、T2(86.41±9.43)次/min;对照组T1(89.53±10.41)次/min、T2(87.46±9.58)次/min]均高于T0时间点[观察组(78.78±4.35)次/min、对照组(79.12±4.41)次/min](P0.05);观察组T1、T2时间点MVP(79.58±5.71、87.53±6.76)mmHg高于对照组(74.12±4.69、75.26±5.61)mmHg(t=9.613、7.223,P=0.011、0.016);观察组的不良反应发生率为6.45%,与对照组的12.90%差异无统计学意义(χ~2=1.214, P=0.643)。结论:将右美托咪啶联合芬太尼用于ICU腹部外科术后机械通气患者中能获得良好的镇痛、镇静效果,缩短苏醒及达到镇静所需时间,血流动力学相对稳定,药物安全性较高,值得推广应用。     

Is routine extubation overnight safe in cardiac surgery patients?

Objectives

Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.