超声心动图对心肌致密化不全的诊断及临床意义探讨

目的：探讨超声心动图对心肌致密化不全的诊断及临床意义。方法：应用Vivid7、HP5500彩色多普勒超声诊断仪（探头频率为2～4MHz）对32例左室心肌致密化不全患者进行检查,采用二维、M型、彩色及频谱多普勒观察病变心肌及心内膜改变,重点观察心尖段。常规测量各腔室内径、左室壁正常段心肌厚度及动度,评价心室舒张功能、计算左心室射血分数EF及瓣膜反流等基本信息。结果：①受累的心室内膜面可见多发异常粗大的、呈蜂窝状的肌小梁和交错深陷的隐窝形成网状结构。②病变区域心室壁外层的致密心肌明显变薄,为中低回声,较正常心肌薄2~4mm,其心肌厚度〈6mm,而内层心肌疏松增厚为强回声。③病变以近心尖部1/3室壁节段最为明显,很少累及室间隔及基底段室壁。④彩色多普勒可示隐窝间隙之间有低速血流与心腔相通。⑤多数患者以渐进性的心功能不全、呼吸困难、体循环栓塞、心律失常为主要表现,本组患者临床表现为心力衰竭22例,心脏杂音3例,心律失常2例,5例无明显不适症状。结论：超声心动图检查是准确、无创诊断心肌致密化不全的首选方法,能够对房室结构和心功能进行全面评价,有助于明确心力衰竭病因并协助治疗,同时也有助于筛查心肌致密化不全家族,对临床治疗起着很好的指导作用。     

探讨超声心动图对心肌致密化不全的诊断及指导治疗价值

目的研究心肌致密化不全的心内结构及心功能的改变,探讨超声心动图对心肌致密化不全的诊断及指导治疗的价值。方法常规检查各切面,主要测量房室内径、室壁厚度及运动幅度、瓣膜血流情况、心功能指数,重点了解室壁心肌结构及舒张末期左室内径、左心室射血分数,观察房室腔内是否有血栓形成。结果 3例患者中有2例单独左心室受累,1例累及双心室。3例患者超声心动图上均有特征性改变,心室内均见异常隆突的肌小梁和深陷其间的隐窝,彩色多普勒超声见肌小梁隐窝内的血流信号与心室腔相通。病变好发于左室心尖部、侧壁、下后壁,伴或不伴心功能不全、心律失常。结论对心肌致密化不全超声心动图具有特征性声像图表现,其检查能够对心肌致密化不全进行房室结构及功能的全面评价,是发现心肌致密化不全的首要方法,也是定期观察治疗后心功能改善的必要手段。     

超声心动图对心肌致密化不全的诊断价值

目的:探讨超声心动图对心肌致密化不全(noncompaction of ventricularmyocardium,NVM)的诊断价值.方法:采用二维、M型及多普勒超声心动图对疑似NVM患者进行多切面扫查.结果:9例患者均为左室受累.超声心动图检查可见左室内多发杂乱的肌小梁和深陷的小梁间隙(即隐窝)交织成的"海绵"样网状结构,其中小梁间隙与心室腔相通,深陷的隐窝内血流与心室腔相交通.非致密化心肌层与致密化心肌层厚度之比大于2.结论:超声心动图是诊断NVM的重要手段,在无明显临床症状时即可诊断,具有特征性意义.     

CRT_D介导室性心动过速的研究进展

心室再同步心脏转复除颤器（CRT）可有效改善心力衰竭（CHF）患者的运动耐量和生活质量,预防猝死,提高生存率,但_DCHFCRTD植入后由于心室激动顺序的改变,使QT间期延长、跨室壁复极离散度（TDR）增加,潜在致室性心律失常风险;且CHF患者通常存在心肌解剖改变,传导的不均一性,也为折返性心动过速的发生提供了维持的机制;而多次电击也可导致肌钙蛋白升高,引起心肌损伤,局部心肌复极离散度增加（DRVR）和QT间期延长,以及电除颤后心肌纤维化和急性细胞损伤,反复室速、室颤也会引起进行性左心功能不全、心肌细胞凋亡、恶化心律失常基质和增加心律失常易感性。CRT_D潜在致室性心律失常作用逐渐引起人们的重视,本文就近年来CRTD致室性心律失常的电生理机制与临床防治对策等做一综述。     

CRT_D介导室性心动过速的研究进展

心室再同步心脏转复除颤器(CRT_D)可有效改善心力衰竭(CHF)患者的运动耐量和生活质量,预防猝死,提高生存率,但CRT_D植入后由于心室激动顺序的改变,使QT间期延长、跨室壁复极离散度(TDR)增加,潜在致室性心律失常风险;且CHF患者通常存在心肌解剖改变,传导的不均一性,也为折返性心动过速的发生提供了维持的机制;而多次电击也可导致肌钙蛋白升高,引起心肌损伤,局部心肌复极离散度增加(DRVR)和QT间期延长,以及电除颤后心肌纤维化和急性细胞损伤,反复室速、室颤也会引起进行性左心功能不全、心肌细胞凋亡、恶化心律失常基质和增加心律失常易感性。CRT_D潜在致室性心律失常作用逐渐引起人们的重视,本文就近年来CRT_D致室性心律失常的电生理机制与临床防治对策等做一综述。     

速度向量成像技术评价心肌梗死患者节段心肌收缩功能

目的:应用速度向量成像技术(VVI)比较静息状态下相同节段的正常心肌、梗死心肌及非梗死心肌纵向和径向的运动特点,评价VVI技术对冠心病心肌梗死患者节段心肌收缩功能的临床应用价值.方法:选取健康志愿者30例和心肌梗死患者30例,分为正常组与心肌梗死组.选取心尖四腔、心尖二腔、心尖左室长轴;二尖瓣水平、乳头肌水平及近心尖部水平左室短轴切面,定量分析左室前间隔、前壁、侧壁、下壁、后壁及后间隔的径向运动,以及纵向的基底段、中间段及心尖段三个分段中梗死节段、非梗死节段及正常节段的心肌速度(Vs),应变(S),应变率(SR).结果:正常人左心室各室壁基底段、中间段和心尖段速度依次递减;应变、应变率差异无统计学意义.左心室各室壁二尖瓣水平切面、乳头肌水平切面、近心尖部水平切面径向速度、应变、应变率差异无统计学意义.心肌梗死组梗死节段VVI测值均降低,与正常组比较差异具有显著性意义.结论:VVI技术可以作为无创的心肌梗死诊断指标,有助于确定或排除冠心病心肌梗死诊断.     

心脏磁共振成像评价缺血性心肌病的临床应用价值

目的:评估心脏磁共振(cardiac magnetic resonance,CMR)功能成像在缺血性心肌病临床诊断中的价值。方法:使用飞利浦3.0T磁共振仪,对32例临床确诊的缺血性心肌病患者进行CMR平扫及钆对比剂动态增强扫描。应用Cardiac MR Analysis软件进行相关后处理分析,计算左室射血分数、室壁增厚率等心功能参数并与超声心动图检查结果相比较。采用17节段分段法分析心脏形态学、心肌组织运动、局部灌注、延迟增强等特点,评价其临床应用价值。结果:所有患者的心功能参数均降低,包括左室射血分数、每搏输出量、心输出量和室壁增厚率,心脏磁共振和超声心动图的测量结果并无明显差异(49%±5.3%vs 52%±8.2%;42.8 mL±8.9 mLvs 45.7 mL±10.6 mL; 3.5 L/min±0.6 L/min vs 3.8 L/min±0.9 L/min; 28%±4%. vs 31%±6%)(P0.05)。所有患者中存在室壁运动异常的为184段(184/544);其中心肌血流灌注信号减低的有136段(136/184),呈现心肌延迟强化的有98段(98/136)。结论:CMR功能成像对于缺血性心肌病的临床诊疗及预后评估可提供与心肌形态及功能相关的重要信息。     

骨髓间充质干细胞移植对心衰大鼠心肌结构和功能的影响

研究骨髓间充质干细胞(MSC)移植对心力衰竭(简称心衰)大鼠心肌结构和功能的影响以及在病损心肌体内分化为心肌细胞的情况。将96只Wistar大鼠,用阿霉素成功诱导了54只心衰模型,随机分成3组,移植组为左室前壁注射MSC,对照组注射培养基,心衰组不给予任何干预措施。由彩色超声心动图(TTE)监测左室心功能参数。8周检测完成后取出心脏标本,做冰冻切片脏染色观察病损心肌结构的变化及免疫荧光检查植入MSC心肌肌球蛋白重链(MHC)及心肌特有的连接蛋白(Cx43)表达情况。结果表明植入的MSC存活并表达了MHC及Cx43,其周围宿主心肌细胞肿胀明显减轻。在移植MSC2周后,心功能开始改善,至8周时,心功改善能更明显。由此得出结论：MSC在病损心肌体内不仅能存活、分化为心肌细胞,使病损心肌组织病变减轻。而且可显著改善心衰大鼠的心功能。     

成人心肌致密化不全的研究进展

成人心肌致密化不全（NVM）是一种特殊少见的心肌病,是由于胚胎发育早期正常心内膜发育停滞所致的心脏病,特征是心内膜面有粗大的肌小梁和交错的深隐窝。临床表现为充力性心力衰竭、心律失常和系统性血栓栓塞等。目前以对症支持治疗为主,预后较差。现介绍其发病机制、病理解剖学、临床特点、诊断及诊断标准、治疗等方面进展,为临床诊断及治疗提供客观依据。近年来医师对该疾病认识的不断提高,使其误诊率和漏诊率有所下降,同时使患者的预后和生活质量得到明显改善,但还存在许多争议,需要进一步探讨。     

斑点追踪技术评价PCI术后左室功能的实验研究

目的:探讨二维斑点成像(speckle tissue imaging,STI)技术在经皮冠状动脉介入治疗(percutaneous coronary intervention,PCI)术后左室节段功能评价中的应用价值.方法:选择67例2011年1月～2012年6月于我院急诊行PCI治疗的急性前壁心肌梗死患者为研究对象,分别于PCI术前和术后72小时、1个月、三个月及六个月内行超声心动图检查,测量其常规超声心动指标E/A及LVEF,并用STI技术测定左室基底部及心尖段的旋转角度及解旋角度.结果:PCI术后患者基底部与心尖部心肌节段旋转及解旋角度均显著提高(P均＜0.05),但LVEF仅在术后六个月较术前提高(P＜0.05),其余时间的E/A及LVEF的变化无统计学意义(P＞0.05).结论:PCI术后患者左室功能改善,表现在心肌节段旋转解旋角度提高,二维STI技术可定量评价PCI患者左室心肌功能的变化.     

Isolated left ventricular noncompaction diagnosed by transthoracic threedimensional echocardiography

A 55-year-old man was admitted to our hospital because of chest distress, associated with activity. Two-dimensional echocardiography (2DE) demonstrated a suspected trabeculation versus false tendon of the left ventricular apex cordis but not meeting the diagnostic criteria of noncompaction of the ventricular myocardium (NVM). Threedimensional echocardiography (3DE) revealed more prominent trabeculations and deeper intertrabecular recesses of the left ventricular apex, which were consistent with the diagnostic criteria of NVM. In contrast to 2DE, 3DE provides wide, pyramid-shaped datasets that encompass the entire left ventricle. (Neth Heart J 2009;17:208–10.)     

The accessory papillary muscle with inferior J-waves - peculiarity or hidden danger?

A 24-year-old woman admitted with mild chest distress associated with activity without chest complaint for twenty days. Two orifices were visible at the level of the mitral valve with a transthoracic short-axis view of the two-dimensional and three-dimensional echocardiography. The left ventricle was mildly dilatated and the left ventricular wall was thickened, especially at the apex and anterolateral wall, and appeared sponge-like. There were numerous, excessively prominent trabeculations associated with intertrabecular recesses. Although the coexistence of NVM and DOMV could be a coincidence, we believe that both defects were probably caused by a developmental arrest of the left ventricular myocardium in the present case.     

对比增强经颅多谱勒超声对心房右向左分流患者的诊断价值的分析

目的:比较对比增强经颅多普勒超声与经胸壁超声心动图、经食管超声心动图对心房右→左分流患者的鉴别诊断价值。方法:回顾性分析2014年9月至2018年11月哈尔滨医科大学附属第一医院经手术证实的41例心房右→左分流患者对比增强经颅多普勒超声及经胸壁超声心动图的检查所见及诊断结果,并回顾性分析其中29例患者对比增强经颅多普勒超声、经胸壁超声心动图及经食管超声心动图的检查所见及诊断结果。结果:在经手术证实的41例心房右→左分流患者中,对比增强经颅多普勒超声检查阳性结果 41例,阴性结果 0例,诊断准确性为100%;经胸壁超声心动图检查阳性结果 20例,阴性结果 21例,诊断准确性为48.8%。其中,同时进行对比增强经颅多普勒超声、经胸壁超声心动图及经食管超声心动图检查的29例患者中,经胸壁超声心动图阳性结果 12例,阴性结果 17例,诊断准确性为41.4%;经食管超声心动图检查阳性结果 24例,阴性结果 5例,诊断准确性为82.8%。结论:对比增强经颅多普勒超声可提高心房右→左分流的诊断准确率,其与经胸壁超声心动图及经食管超声心动图结合应用可提高心房右→左分流的鉴别诊断能力。     

Noncompaction of the ventricular myocardium is associated with a de novo mutation in the beta-myosin heavy chain gene

Noncompaction of the ventricular myocardium (NVM) is the morphological hallmark of a rare familial or sporadic unclassified heart disease of heterogeneous origin. NVM results presumably from a congenital developmental error and has been traced back to single point mutations in various genes. The objective of this study was to determine the underlying genetic defect in a large German family suffering from NVM. Twenty four family members were clinically assessed using advanced imaging techniques. For molecular characterization, a genome-wide linkage analysis was undertaken and the disease locus was mapped to chromosome 14ptel-14q12. Subsequently, two genes of the disease interval, MYH6 and MYH7 (encoding the alpha- and beta-myosin heavy chain, respectively) were sequenced, leading to the identification of a previously unknown de novo missense mutation, c.842G>C, in the gene MYH7. The mutation affects a highly conserved amino acid in the myosin subfragment-1 (R281T). In silico simulations suggest that the mutation R281T prevents the formation of a salt bridge between residues R281 and D325, thereby destabilizing the myosin head. The mutation was exclusively present in morphologically affected family members. A few members of the family displayed NVM in combination with other heart defects, such as dislocation of the tricuspid valve (Ebstein's anomaly, EA) and atrial septal defect (ASD). A high degree of clinical variability was observed, ranging from the absence of symptoms in childhood to cardiac death in the third decade of life. The data presented in this report provide first evidence that a mutation in a sarcomeric protein can cause noncompaction of the ventricular myocardium.     

The PhysioFlow Thoracic Impedancemeter Is Not Valid for the Measurements of Cardiac Hemodynamic Parameters in Chronic Anemic Patients

The aim of the present study was to test the validity of the transthoracic electrical bioimpedance method PhysioFlow® to measure stroke volume in patients with chronic anemia. Stroke volume index (SVI), as well as cardiac index (CI) obtained by transthoracic electrical bioimpedance method and doppler echocardiography were compared in healthy subjects (n = 25) and patients with chronic anemia (i.e. mainly with sickle cell anemia; n = 32), at rest. While doppler echocardiography was able to detect difference in SVI between the two populations, the Physioflow® failed to detect any difference. Bland & Altman analyses have demonstrated no interchangeability between the two methods to assess CI and SVI in anemic patients and healthy subjects. While doppler echocardiography displayed a good concordance for SVI results with those obtained in the literature for anemic patients, the Physioflow® did not. Finally, in contrast to doppler echocardiography: 1) the CI obtained with the Physioflow® was not correlated with the hemoglobin level and 2) the stroke volume determined by the Physioflow® was highly influenced by body surface area. In conclusion, our findings indicate that the Physioflow® device is inaccurate for the measurement of SVI and CI in patients with chronic anemia and has a poor accuracy for the measurement of these parameters in African healthy subjects.     

Noncompaction of the Ventricular Myocardium Is Associated with a De Novo Mutation in the β-Myosin Heavy Chain Gene

Noncompaction of the ventricular myocardium (NVM) is the morphological hallmark of a rare familial or sporadic unclassified heart disease of heterogeneous origin. NVM results presumably from a congenital developmental error and has been traced back to single point mutations in various genes. The objective of this study was to determine the underlying genetic defect in a large German family suffering from NVM. Twenty four family members were clinically assessed using advanced imaging techniques. For molecular characterization, a genome-wide linkage analysis was undertaken and the disease locus was mapped to chromosome 14ptel-14q12. Subsequently, two genes of the disease interval, MYH6 and MYH7 (encoding the α- and β-myosin heavy chain, respectively) were sequenced, leading to the identification of a previously unknown de novo missense mutation, c.842G>C, in the gene MYH7. The mutation affects a highly conserved amino acid in the myosin subfragment-1 (R281T). In silico simulations suggest that the mutation R281T prevents the formation of a salt bridge between residues R281 and D325, thereby destabilizing the myosin head. The mutation was exclusively present in morphologically affected family members. A few members of the family displayed NVM in combination with other heart defects, such as dislocation of the tricuspid valve (Ebstein''s anomaly, EA) and atrial septal defect (ASD). A high degree of clinical variability was observed, ranging from the absence of symptoms in childhood to cardiac death in the third decade of life. The data presented in this report provide first evidence that a mutation in a sarcomeric protein can cause noncompaction of the ventricular myocardium.     

脑内P物质在谷氨酸兴奋腹内侧核引起的升压反应中之作用

目的：分析谷氨酸兴奋下兵脑腹内侧核（NVM）引起升压反应的机制。方法：大鼠脑内或静脉注射不同药物,记录血压和心率的变化。结果：①L－谷氨酸（Glu)兴奋NVM、P物质（SP）注入背内侧核（NDM）室旁核（NPV）或延髓头端腹外侧区（RVL）均引起升压反应;②NVM升压反应可被双侧NDM、NPV或PVL内预先注射[D-Pro^2,D-Phe^7,D-Trp^9]-P物质（SP拮抗剂）衰减,但RVL内注射阿托品无此效应;③酚妥拉明（i.v.）也能使NVM升压反应减小,而心得安或甲基阿托品（i.v.）对该升压反应无影响。结论：兴奋NVM可通过NDM（SP受体）,作用于NPV（SP受体）升压区和RVL（SP受体）－交感缩血管神经系统产生升压反应。心交感和心迷走神经不参与该反应。     

左肾动脉缩窄诱导心肌肥大大鼠心肌蛋白差异表达研究

目的：应用蛋白质组学方法分析病理性心肌肥大心肌细胞蛋白表达特征。方法：雄性SD大鼠16只,分为2组（n=8）：两肾一夹组（2K1C）和假手术组（SO）,术后饲养8周,使用普通多普勒和组织多普勒鉴定动物模型,然后提取心肌总蛋白,应用二维凝胶电泳技术,建立分辨率高和重复性良好的凝胶图像,质谱（MALDI—TOF-MS）鉴定差异蛋白点,与网络数据库进行匹配,并对鉴定蛋白进行分类。结果：两肾一夹大鼠心肌细胞有21个蛋白点表现出显著增加或减少,经数据库匹配,获得14种差异表达的蛋白质。结论：两肾一夹大鼠心肌出现一些差异表达蛋白席官们可能在病理性心肌肥大的发生中起重要作用。