心肌应变率在射血分数正常的心力衰竭合并心房纤颤患者心功能评价中的应用

目的分析心肌应变率(SR)在射血分数(EF)正常的心力衰竭(CHF)合并心房纤颤(房颤)患者心功能评价中的应用。方法 102例CHF患者左室EF(LVEF)均正常,其中,房颤组52例,非房颤组50例,同期50例查体健康者为对照组。观察3组左心房内径(LA)、左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、LVEF、心肌质量指数(LVMI)、心率(HR)、E峰、A峰、E/A、基底段、中间段和心尖段的心肌收缩期峰值应变、左室收缩期左房应变率峰值(SRS)、左室舒张早期左房应变率峰值(SRE)和左室舒张晚期左房应变率峰值(SRA)差异变化。结果 3组超声心动图指标变化差异有统计学意义(P<0.05)。房颤组LA、LVEDV、LVESV、LVMI、HR、E峰和E/A显著高于非房颤组及对照组,而A峰则明显低于非房颤组及对照组(P<0.05)。3组LVEF差异无统计学意义(P>0.05),与病理生理改变不符;3组心肌收缩期峰值应变差异显著(P<0.05)。房颤组左心室后间隔和侧壁的基底段、中段和心尖段明显低于非房颤组及对照组,3组SRS、SRE、SRA在各节段差异变化明显,房颤组后间隔和侧壁SRS、SRE、SRA在左心室各节段显著低于非房颤组及对照组(P<0.05)。结论 SR技术作为一种无创定量方法在EF正常CHF合并房颤患者的心功能评价中优于超声心动图指标。     

应变率成像评价扩张型心肌病左室局部心肌收缩和舒张功能

目的 应用应变率成像(SRI)技术评价扩张型心肌病(DCM)患者左心室局部心肌长轴方向收缩和舒张功能.方法 获取18例DCM患者和40例正常对照组心尖左室长轴、心尖两腔、心尖四腔的心肌应变率曲线,测量并比较两组各室壁各节段水平的收缩期、舒张早期、舒张晚期的峰值应变率(SRs、SRe、SRa).测量左室射血分数(LVEF)和二尖瓣口血流的E峰、A峰.结果 DCM组各节段水平的SRs、SRe、SRa明显低于正常对照组(P＜0.05或P＜0.01).结论 SRI技术能准确可靠地评价DCM患者左室局部心肌收缩和舒张功能.     

定量组织速度成像与应变率成像评价急性前壁心肌梗死患者心功能的应用价值

目的:观察急性前壁心肌梗死患者心肌速度(V)、应变率(SR)的变化特点,探讨定量组织速度成像(QTVI)及应变率成像(SRI)技术定量评价急性心肌梗死(AMI)患者的左室局部梗死心肌功能的临床应用价值。方法:应用QTVI及SRI对20例AMI患者和30例正常人左室前壁及前间壁节段纵向收缩期(S)、舒张早期(E)及房缩期(A)的峰值速度(VS、VE、VA)、峰值应变率(SRS、SRE、SRA)进行测定,并以冠脉造影结果为标准进行对比分析。结果:VS:AMI组心梗室壁的不同水平均较正常对照组显著性减低;VE:除前间隔的心尖水平外,心梗室壁较正常对照组显著性减低;VA:前壁的不同水平及前间隔的心尖水平AMI组较对照组显著性减低;SRS、SRE:AMI组不同水平左室心梗室壁较对照组显著性减低;SRA:前壁的不同水平及前间隔的基底水平AMI组较对照组显著性减低(分别P<0.01和P<0.05)。结论:QTVI及SRI技术是临床无创、定量评价急性心肌梗死局部心肌功能的有效方法。     

定量组织速度成像与应变率成像在急诊心肌缺血中的应用价值

目的探讨定量组织速度成像(QTVI)及应变率成像(SRI)在急诊心肌缺血中的临床应用价值。方法应用QTVI及SRI对32例急诊心肌缺血病人和30例正常人节段纵向收缩期(S)、舒张早期(E)及收缩期(A)的峰值速度(VS、VE、VA)、峰值应变率(SRS、SRE、SRA)进行测定。结果 VS:心肌缺血组室壁的不同水平均较正常对照组显著性减低;VE:除前间隔的心尖水平外,室壁较正常对照组显著性减低;VA:前壁的不同水平及前间隔的心尖水平心肌缺血组较对照组显著性减低;SRS、SRE:心肌缺血组不同水平左室室壁较对照组显著性减低;SRA:前壁的不同水平及前间隔的基底水平心肌缺血组较对照组显著性减低(P0.05或P0.01)。结论 QTVI及SRI技术是临床简便、无创,是准确评价急诊心肌缺血的有效方法。     

二维应变技术对不同分期慢性肾脏病患者左室功能的评价

目的:探讨二维应变技术（2DS）评价不同分期慢性肾脏病患者左室收缩功能的价值。方法:100名慢性肾脏病患者按肾小球滤过率分为3组,A组（n=30）、B组（n=30）及C组（n=40）,同时选取30名健康志愿者为正常对照组,分别取二维条件下心尖四腔切面、心尖两腔切面、心尖长轴切面3个连续心动周期图像。应用2DS获取左室18个节段心肌应变(s)及舒张早期应变率（SRe）,并计算整体应变（GLS）。结果:A组左室壁部分节段应变、应变率低于正常组。B组除间隔心尖段、下壁基底段、中间段以外,其余各节段收缩期应变均低于正常组, B组、C组各节段舒张早期应变率均低于正常组。其中,C组除前壁中间段、后壁心尖段以外,其他节段均较A组降低。B组、C组整体应变低于正常。结论:二维应变技术可以早期发现慢性肾脏病患者左室心肌收缩及舒张功能的异常。     

应用应变率成像技术对尿毒症患者左心室功能的评价

目的 应用应变率成像技术评价尿毒症患者左室的局部收缩与舒张功能。方法 40例尿毒症患者,左室肥厚(LVH)组25例,非左室肥厚(NLVH)组15例及30例正常对照组。取心尖四腔、心尖两腔、心尖左室长轴切面测量左室各室壁心肌收缩期、舒张早期、房缩期的峰值速度(VS、VE、VA)、峰值应变率(SRS、SRE、SRA)、最大应变及位移。结果 速度Vs、VA:尿毒症患者较正常对照组无显著性差异,VE:尿毒症患者NLVH组后间隔、下壁较正常对照组显著性减低,LVH组除后壁外余左室各壁较正常对照组显著性减低。尿毒症患者两组间仅在前间隔有显著性差异。应变率SRS:尿毒症患者LVH组左室侧壁较正常对照组显著性减低。SRE:尿毒症患者NLVH组左室侧壁、下壁、后壁较正常对照组显著性减低,LVH组除后间隔外左室各壁较正常对照组显著性减低。LVH组前间隔及前壁的SRE较NLVH组显著性减低。SRA:尿毒症患者较正常对照组无显著性差异。应变S:尿毒症患者NLVH组仅有左室侧壁较正常对照组有显著性差异,LVH组除后间隔外其余左室壁较对照组显著性减低。LVH组前壁的应变较NLVH组显著性减低。位移D:尿毒症患者NLVH组仅在后间隔较正常对照组显著性减低,LVH组后间隔、后壁、前间隔、下壁较正常对照组显著性减低(分别P<0.05和0.01)。结论 应变率成像技术能够早期评尿毒症患者左室的心肌运动功能。     

应变率成像评价冠心病支架置入术前后左心室局部收缩功能变化的研究

目的:探讨应变率成像技术(SRI)定量评价冠心病支架置入术后早期左心室局部收缩功能变化的临床价值。方法:50例经冠状动脉造影(CAG)证实存在左前降支(LAD)75%～100%不同程度的狭窄,分别在LAD支架置入术前1～3d,术后7d、3个月测量前壁及前间隔的基底段、中间段和心尖段的收缩期应变率(SRs)及左心室局部收缩功能的变化,测量左心室射血分数(LVEF),并与正常对照组(50例)进行比较。结果:与术前相比,术后7d各节段心肌的应变率均有增加(P<0.05),术后3个月各节段心肌的应变率、LVEF明显增加(P<0.01)。术前平均LVEF为0.468±0.076,术后7d增加为0.517+0.059(P<0.05),术后3个月则增加0.587±0.038(P<0.01)。结论:SRI可以无创定量评价冠心病冠状动脉支架置入术后早期左心室局部收缩功能的变化。     

应变率成像技术检测肺心病左心室收缩功能的临床应用

目的探讨应变率成像(SRI)技术评价慢性肺心病患者左心室收缩功能的价值。方法选取慢性肺心病患者64例(其中心功能代偿组30例,心功能失代偿组34例)及正常对照组30例,应用SRI技术测量左心室各壁基底段、中段的心肌收缩期峰值应变率(SRs),计算左心室收缩期平均峰值应变率(mSRs),并与常规超声心动图指标进行对比。结果与正常对照组比较,慢性肺心病组mSRs均显著升高,差异有统计学意义(P<0.01),且代偿组与失代偿组mSRs比较差异有统计学意义(P<0.05)。结论 SRI技术较常规超声心动图能更敏感、快速地定量评价慢性肺心病患者左心室收缩功能。     

应变率成像评价自体外周血干细胞移植术后心肌梗死患者左室局部心肌功能的临床研究

目的探讨应变（SI）及应变率成像（SRI）在急性心肌梗死（AMI）患者自体外周血干细胞移植治疗前、后左室局部心肌功能定量评价中的应用价值。方法共有65例AMI患者入选本项前瞻性、非随机、开放试验（其中35例患者为细胞移植组，30例为常规治疗组）。应用SRI、SI和多普勒速度成像（TVI）测定细胞移植组、常规治疗组治疗前、后及30名健康人的左室壁各节段的SI、SRI及TVI的参数变化。结果①65例AMI患者的589个缺血节段的心肌收缩期峰值应变率（PSSR）、舒张早期峰值应变率（PESR）、收缩期峰值应变（PSS）、心肌收缩期峰值速度（VS）和舒张早期峰值速度（Ve）显著降低，舒张晚期峰值应变率（PASR）和舒张晚期峰值速度（Va）变化差异无统计学意义。SRI和SI检出缺血心肌的敏感性、特异性及准确性明显高于TVI[（90％、91％、92％）比（71％、69％、71％），P〈0．01]。②细胞移植组随访期305个经治疗缺血心肌节段中，244个节段的PSSR、PESR、PSS、Vs及ve较术前显著增高或恢复正常，常规治疗组随访期284个经治疗缺血节段中，169个节段的PSSR、PESR、PSS、Vs及Ve较术前显著增高或恢复正常，但两组治疗后改善的缺血心肌节段数比例及SRI、TVI参数比较差异有统计学意义（P〈0．01）。结论SRI和SI能够无创定量评价冠心病缺血心肌节段的运动异常，为临床客观评价冠脉内自体干细胞移植术疗效提供了一种早期无创、敏感、有效的定量分析手段。     

应用定量组织速度图、组织位移、应变及应变率评价正常人左心室局部心肌功能

目的观察左室节段性心肌组织速度、位移、应变及应变率的正常值以及它们与年龄的关系。方法对132例健康志愿者行组织多普勒检查,测量左心室各壁各节段心肌的峰值速度、组织追踪、应变及应变率。结果①心肌的峰值速度（V）:不同室壁及同一室壁的不同节段有显著的差异性（P<0.05,P<0.01）,收缩期峰值速度（VS）、舒张早期峰值速度（VE）与年龄负相关（分别为r=-0.52、r=-0.72,P<0.01）,舒张晚期峰值速度（VA）与年龄呈正相关（r=0.46,P<0.01）。②组织位移（Ds）:不同室壁及同一室壁的不同节段有显著的差异性（P<0.05,P<0.01）,与年龄呈负相关（r=-0.41,P<0.01）。③心肌应变（ε）:不同室壁的相同节段无显著差异性;同一室壁的不同节段有显著的差异性（P<0.01）,与年龄呈负相关性（r=-0.28,P<0.01）。④心肌应变率:收缩期应变率（Ssr）:不同室壁及同一室壁的不同节段有显著的差异性（P<0.05,P<0.01）,与年龄无相关性（r=-0.14）。舒张早期应变率（Esr）:不同室壁及同一室壁的不同节段无显著的差异性,与年龄呈负相关（r=-0.20,P<0.05）。舒张晚期应变率（Asr）:不同室壁及同一室壁的不同节段无显著的差异性,与年龄呈正相关（r=0.28,P<0.01）。⑤所有数据两性之间无显著差异性。结论大多数参数如心肌组织速度、位移、应变及应变率在不同室壁、不同节段有显著的差异性,与年龄相关。     

Echocardiographic strain and strain rate imaging--clinical applications

Echocardiographic strain and strain rate imaging is a new technology enabling more reliable and comprehensive assessment of myocardial function. The spectrum of potential clinical applications is very wide due to its ability to differentiate between active and passive movement of myocardial segments, to quantify intraventricular dyssynchrony and to evaluate components of myocardial function, such as longitudinal myocardial shortening, that are not visually assessable. The high sensitivity of both tissue Doppler (TDI) derived and two-dimensional (2D) speckle tracking derived strain and strain rate data for the early detection of myocardial dysfunction recommend these new non-invasive diagnostic methods for routine clinical use. In addition to early detection of myocardial dysfunction of different etiologies, assessment of myocardial viability, detection of acute allograft rejection after heart transplantation and early detection of patients with transplant coronary artery disease, strain and strain rate measurements are helpful in the selection of different therapies and follow-up evaluations of myocardial function after different medical and surgical treatment. Strain and strain rate data also provide important prognostic information. This Review explains the fundamental concepts of strain and strain rate for both TDI-derived and speckle tracking 2D-strain derived deformation imaging and discusses the clinical applicability with all the major advantages and limitations of these new echocardiographic methods, which recently have become a subject of great interest for clinicians.     

Muscle strain injuries

Muscle injuries--lacerations, contusions or strains--are by far the most common injuries in sports. After first aid following the RICE principle (Rest, Ice, Compression and Elevation), therapy must be tailored according to the severity of the injury and based on the knowledge gained from experimental studies on regeneration of injured muscle. Most muscle injuries can be treated conservatively with excellent recovery, but complete ruptures with complete loss of function should be managed surgically. Immediately after the injury, a short period of immobilization is needed to accelerate formation of the scar between the stumps of the ruptured myofibers, to which the stumps adhere. The optimal length of immobilization depends on the grade of the injury, and should not be longer than needed for the scar to bear the pulling forces without rerupture. Early mobilization is required to invigorate adhesion, orientation of the regenerating muscle fibers, revascularization and resorption of the connective tissue scar. Another important aim of early mobilization, especially in clinical sports medicine, is to minimize inactivity-induced atrophy as well as loss of strength and extensibility, which are rapidly appearing adverse sequelae of prolonged immobilization.     

Repetitive strain injury

Repetitive strain injury remains a controversial topic. The term repetitive strain injury includes specific disorders such as carpal tunnel syndrome, cubital tunnel syndrome, Guyon canal syndrome, lateral epicondylitis, and tendonitis of the wrist or hand. The diagnosis is usually made on the basis of history and clinical examination. Large high-quality studies using newer imaging techniques, such as MRI and ultrasonography are few. Consequently, the role of such imaging in diagnosis of upper limb disorders remains unclear. In many cases, no specific diagnosis can be established and complaints are labelled as non-specific. Little is known about the effectiveness of treatment options for upper limb disorders. Strong evidence for any intervention is scarce and the effect, if any, is mainly short-term pain relief. Exercise is beneficial for non-specific upper limb disorders. Immobilising hand braces and open carpal tunnel surgery release are beneficial for carpal tunnel syndrome, and topical and oral non-steroidal anti-inflammatory drugs, and corticosteroid injections are helpful for lateral epicondylitis. Exercise is probably beneficial for neck pain, as are corticosteroid injections and exercise for shoulder pain. Although upper limb disorders occur frequently in the working population, most trials have not exclusively included a working population or assessed effects on work-related outcomes. Further high-quality trials should aim to include sufficient sample sizes, working populations, and work-related outcomes.     

Left ventricular size determines tissue Doppler-derived longitudinal strain and strain rate

AIMS: Tissue Doppler-derived indices of strain (epsilon) and strain rate (SR) have been developed to assess regional cardiac function. However, the effect of left ventricular (LV) size on epsilon and SR has not been studied in depth. The aim of this study was to assess to what extent heart size influence epsilon or SR. METHODS AND RESULTS: In 21 anaesthetized pigs ranging from 12.5 to 70.0 kg, tissue Doppler-derived epsilon and SR, and haemodynamic parameters, were assessed during controlled heart rates and different loading conditions. dP/dt did not correlate to pig weight, suggesting constant contractility during growth. Longitudinal epsilon and SR were significantly higher in smaller compared with larger hearts. The hyperbolic correlation between pigs weight and epsilon and SR was r(2)=0.621 and 0.372, respectively, both P<0.0001. Afterload elevation induced a reduction in longitudinal epsilon (from -24.2+/-3.2 to -12.1+/-5.5%, P=0.001) and SR (from -2.3+/-0.8 to -1.3+/-2.4 s(-1), P=0.034), whereas increasing preload increased epsilon (from -26.4+/-10.3 to -38.1+/-14.3%, P=0.006) and SR (from -2.3+/-0.9 to -4.22+/-1.8 s(-1), P=0.002). CONCLUSION: Longitudinal epsilon and SR decrease with increasing LV dimensions in spite of an unaltered contractility. These results show and confirm that heart size influences epsilon and SR, which are highly load-dependent parameters.     

辽宁与四川两省嗜人按蚊细胞遗传学研究

目的　确定辽宁省可疑按蚊与嗜人按蚊的遗传关系。方法　以人工诱导法和自然交配法对辽宁省可疑嗜人按蚊与四川省嗜人按蚊进行杂交实验 ,观察杂交卵的孵化率、幼虫生长情况、化蛹率、羽化率 ,判定辽宁省可疑嗜人按蚊与四川省嗜人按蚊是否存在生殖隔离 ;按Kanda法制作幼虫唾腺染色体 ,观察杂交F1代幼虫唾腺染色体联会情况。结果　两地按蚊人工诱导杂交卵的孵化率为 72 36 % ,化蛹率 70 13% ,羽化率 92 5 4 % ;自然交配孵化率、化蛹率和羽化率分别为 87 72 %、70 99%和 95 0 9%。杂交F1代与亲本回交和自交 ,杂交F2 代均能正常发育。杂交F1代幼虫唾腺染色体完全联会。结论　两地嗜人按蚊不存在生殖隔离 ,辽宁省可疑按蚊确系嗜人按蚊无疑。     

心房超声应变和应变率成像在心房颤动中的应用价值

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