单心动周期三维超声评价心梗后的左心收缩功能及同步性

目的应用单心动周期三维超声评价心肌梗塞患者的左心收缩功能及同步性,以便方便、快捷、准确地识别心肌梗塞的节段。方法正常组30例,心梗组27例,先用二维Simpson’S法测定左室整体EF值,再用单心动周期三维超声测左室整体EF值、SDll7值、DDI17值及各节段的容积时间曲线、EF值曲线。比较各组间参数的差异及相关性。结果正常组2D法和4D法测得的左室射血分数无明显差异。心梗组2D法和4D法测得的左室射血分数差异显著。正常组和心梗组的SD117值差异显著,DDI17值在两组间无明显差异。结论单心动周期三维超声心动图能全面真实地显示左室的几何形态,本研究显示心梗后左室整体EF值下降,17节段容积一时间曲线同步性差,曲线图直观明了,可以方便、快捷、准确地识别心肌梗塞的节段。     

LONG-TERM INHIBITION OF Na~ /H~ EXCHANGE ATTENUATES CARDIAC REMODELING AFTER MYOCARDIAL INFARCTION IN RATS

ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅＮａ /Ｈ ｅｘｃｈａｎｇｅｒ (ＮＨＥ)ｉｓａｐＨ ｒｅｇｕｌａｔｏｒｙｐｒｏｔｅｉｎｐｒｅｓｅｎｔｉｎｔｈｅｐｌａｓｍａｍｅｍ ｂｒａｎｃｅｏｆｃａｒｄｉｏｍｙｏｃｙｔｅｓａｎｄｏｔｈｅｒｃｅｌｌｔｙｐｅｓ.ＡｌｔｈｏｕｇｈｓｅｖｅｒａｌｉｓｏｆｏｒｍｓｏｆＮＨＥｈａｖｅｂｅｅｎｄｅ ｃｒｉｂｅｄ,ｔｈｅｐｒｅｄｏｍｉｎａｎｔｉｓｏｆｏｒｍｉｎｔｈｅｈｅａｒｔｉｓｔｈｅｕｂｉｑｕｉｔｏｕｓＮＨＥ 1 ,ｗｈｉｃｈｕｎｄｅｒｃｅｎｔａｉｎｐｈｙｓｉｏｌｏｇｉｃａｌｃｏｎｄｉｔｉ…     

Long-term inhibition of Na+/H+ exchange attenuates cardiac remodeling after myocardial infarction in rats

Objective: In addition to pH regulation, Na⁺/H⁺ exchange (NHE) has been shown to facilitate cell growth and proliferation. However, the effects of long-term inhibition of Na⁺/H⁺ exchange on cardiac structural and functional remodeling post myocardial infarction (MI) are still controversial. The present study was therefore carried out to further investigate the effects of long-term treatment with cariporide, a specific inhibitor of NHE-1, on cardiac remodeling after MI in rats; Methods: Male Wistar rats that underwent coronary ligation were randomly selected for cariporide treatment starting 6 h after induction of MI or no treatment. Treatment was continued up to 6 weeks post MI, after which, the arterial, venous and left ventricular catheters were chronically implanted. Twenty-four h later, after hemodynamic signals were recorded in conscious rats, they were sacrificed and hearts were taken out for morphological examinations; Results: Cariporide treatment decreased the heart weight and heart weight to body weight ratio (bothP<0.05), decreased left ventricular end-diastolic pressure (P<0.001), improved myocardial contractility (dP/dt _max) (P<0.05) and tended to increase the survival of treated rats compared to that of untreated infarct rats; Conclusion: The results of the present study indicate that the long-term inhibition of NHE with cariporide can attenuate cardiac structural remodeling and improve left ventricular dysfunction in infarcted rats, and suggest that Na⁺/H⁺ exchange inhibition could be an effective therapeutic strategy for myocardial infarction-induced heart failure.     

肠淋巴液对休克大鼠心肌特性的影响

大鼠重度失血性休克30min后,左心室内压的最大上升速率( dp/dt max)和左心室收缩压(LVSP)都显著下降(P<0.01),而左心室舒张末压(LVEDP)却有所增高(P<0.05)。说明心肌的收缩功能和舒张功能均出现障碍,给少量淋巴液后(用量为0.5ml/100g体重)使休克时下降的左心室内压的最大上升速率和左心室收缩压显著回升(P<0.05),而增高的左心室舒张末压回落不明显,提示淋巴液可改善休克心肌的收缩功能障碍,但对低血容量情况下的心肌舒张功能无明显改善。     

Improved myocardial perfusion and cardiac function by controlled-release basic fibroblast growth factor using fibrin glue in a canine infarct model

Objective: Angiogenic therapy is emerging as a potential strategy for the treatment of ischemic heart disease but is limited by a relatively short half-life of growth factors.Fibrin glue (FG) provides a reservoir for controlledrelease of growth factors.The aim of this study was to evaluate the effects of basic fibroblast growth factor (bFGF) incorporating FG on angiogenesis and cardiac performance in a canine infarct model.Methods: Acute myocardial infarction was induced by ligation of the left anterior descending coronary artery (LAD).Group I (n=6) underwent ligation of LAD alone.In Group II,transmural channels were created in the infarct area (n=6).In Group III,nontransmural channels were created to locate FG cylinders containing bFGF (n=6).Eight weeks after operation,myocardial perfusion was assessed by single photon emission computed tomography,cardiac function by echocardiography,and vascular development by immunohistochemical staining.Results: Total vascular density and the number of large vessels (internal diameter ≥50 μm) were dramatically higher in Group III than in Groups I and II at eight weeks.Only the controlled-release group exhibited an improvement in regional myocardial perfusion associated with lower defect score.Animals in Group III presented improved cardiac regional systolic and diastolic functions as well as global systolic function in comparison with the other two groups.Conclusions: Enhanced and sustained angiogenic response can be achieved by controlled-release bFGF incorporating FG within transmyocardial laser channels,thus enabling improvement in myocardial perfusion and cardiac function.     

Human bone marrow-derived mesenchymal stem cells transplanted into damaged rabbit heart to improve heart function

INTRODUCTION Congestive heart failure is the end stage of manycardiovascular diseases. Myocardial infarction (MI)is a life-threatening event that may cause suddencardiac death and heart failure. Despite considerableadvances in diagnosis and treatment of heart disease,cardiac dysfunction after MI is still the majorworldwide cardiovascular disorder. Damaged myo-cardium after acute MI is gradually replaced by fi-brotic noncontractile cells to form scar tissue. Thedeveloping ventricul…     

Optimal time for mesenchymal stem cell transplantation in rats with myocardial infarction

Background:Bone marrow mesenehymal stem cell(MSC)transplantation is a promising strategy in the treatment of myocardial infarction(MI).However,the time for transplanting cells remains controversial.The aim of this study was to find an optimal time point for cell transplantation.Methods:MSCs were isolated and cultured from Sprague-Dawley(SD) rats.MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery.MSCs were directly injected into the infarct berder zone at 1 h,1 week and 2 weeks after MI,respectively.Sham-operated and MI centrel groups received equal volume of phosphate buffered saline(PBS).At 4 weeks after MI,cardiac function Was assessed by echocardiography;vessel density Was analyzed on hematoxylin-eosin stained slides by light microscopy;the apoptosis of cardiomyocytes Was evaluated by terminal deoxynucleotidy1 transferase-mediated dUTP nick end-labeling(TUNEL) assay;the expressions of proteins were analyzed by Western blot.Results:MSC transplantation improved cardiac function.reduced the apoptosis of cardiomyocytes and increased vessel density.These benefits were more obvious in l-week group than in 1-h and 2-week groups.There are more obvious increases in the ratio of bc1-2/bax and the expression of vascular endothelial growth factor(VEGF)and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups.Conclusion:MSC transplantation was beneficial for the recovery of cardiac function.MSC transplantation at l week post-MI exerted the best effects on increases of cardiac function,anti-apoptosis and angiogenesis.     

黄芪预处理对麻醉家兔心肌缺血再灌注损伤的保护作用

目的:观察黄芪预处理对家兔心肌缺血再灌注损伤的保护作用。方法:采用在体家兔冠状动脉阻断的缺血/复灌损伤模型,测定心肌梗死面积、血浆中乳酸脱氢酶(LDH)和肌酸激酶(CK)活性及各项心室力学指标。结果:与单纯缺血/复灌组相比,黄芪预处理明显降低心脏缺血/复灌后的梗死面积和血浆中LDH、CK含量,促进左室收缩压(LVSP)、最大左室收缩速率( dP/dtmax)和最大左室舒张速率(-dP/dtmax)的恢复。结论:黄芪预处理对麻醉家兔心肌缺血再灌注所致心肌损伤具有保护作用。     

Elevated high sensitive C-reactive protein and apelin levels after percutaneous coronary intervention and drug-eluting stent implantation

Objective:Percutaneous coronary intervention(PCI) triggers an acute inflammatory response,while sirolimus is known to have anti-inflammatory properties;the inflammatory system response to PCI after sirolimus-eluting stent placement remains unclear.The purpose of this study is to determine the changes in high sensitive C-reactive protein(hs-CRP) and apelin after PCI procedure and drug-eluting stent implantation in patients with and without reduced left ventricular systolic function.Methods:Forty-eight consecutive patients undergoing PCI at the Beijing Anzhen Hospital between July and September 2006 were recruited.Sirolimus-eluting stents were employed in all patients.Blood samples were drawn immediately before and 24 h after the procedure.Plasma hs-CRP and apelin levels were determined by enzyme immunoassay.Results:Paired t-test revealed a significant increase in both hs-CRP and apelin post-procedure(P=0.006 and P0.0001,respectively).Patients with reduced left ventricular ejection fraction(LVEF) had significantly lower baseline apelin levels compared to those with normal ventricular function [(46.8±10.8) vs.(72.0±8.4) pg/ml,P0.001].However,apelin increased to a level similar to the level of those with normal left ventricular systolic function 24 h after the PCI procedure [(86.7±11.6) vs.(85.1±6.1) pg/ml,P=0.72].Conclusions:hs-CRP and apelin levels increased after PCI and sirolimus-eluting stent implantation.Patients with impaired left ventricular systolic function had significantly lower baseline apelin levels,which increased significantly after PCI.     

Polymorphisms in the genes for coagulation factor II,V,VII in patients undergoing coronary angiography

INTRODUCTIONCoronaryarterydisease (CAD)continuestobethemajorcauseofmorbidityandmortalityinourcountry .TheactivityofbloodcoagulationfactorshasbeenshowntobeanimportantriskindicatorforCAD .However,circulatinglevelsofcoagulationfactorsmaynotaccuratelyreflectt…     

Low‐intensity pulsed ultrasound ameliorates angiotensin II-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway

ObjectiveCardiac hypertrophy and fibrosis are major pathological manifestations observed in left ventricular remodeling induced by angiotensin II (AngII). Low-intensity pulsed ultrasound (LIPUS) has been reported to ameliorate cardiac dysfunction and myocardial fibrosis in myocardial infarction (MI) through mechano-transduction and its downstream pathways. In this study, we aimed to investigate whether LIPUS could exert a protective effect by ameliorating AngII-induced cardiac hypertrophy and fibrosis and if so, to further elucidate the underlying molecular mechanisms.MethodsWe used AngII to mimic animal and cell culture models of cardiac hypertrophy and fibrosis. LIPUS irradiation was applied in vivo for 20 min every 2 d from one week before mini-pump implantation to four weeks after mini-pump implantation, and in vitro for 20 min on each of two occasions 6 h apart. Cardiac hypertrophy and fibrosis levels were then evaluated by echocardiographic, histopathological, and molecular biological methods.ResultsOur results showed that LIPUS could ameliorate left ventricular remodeling in vivo and cardiac fibrosis in vitro by reducing AngII-induced release of inflammatory cytokines, but the protective effects on cardiac hypertrophy were limited in vitro. Given that LIPUS increased the expression of caveolin-1 in response to mechanical stimulation, we inhibited caveolin-1 activity with pyrazolopyrimidine 2 (pp2) in vivo and in vitro. LIPUS-induced downregulation of inflammation was reversed and the anti-fibrotic effects of LIPUS were absent.ConclusionsThese results indicated that LIPUS could ameliorate AngII-induced cardiac fibrosis by alleviating inflammation via a caveolin-1-dependent pathway, providing new insights for the development of novel therapeutic apparatus in clinical practice.     

应用新技术观察生脉注射液对左室舒张变化率的影响

本实验采用心导管技术，以左心室舒张末期压力下降最大变化速率（每分钟－dp/dt）为指标，观察了生脉液对家兔急性心肌缺血引起的心舒末期每分钟－dp/dt的影响。其结果表明,脉液可以改善由于心肌缺血而致的左心舒张力功能的不足，使每分钟－dp/dt明显增加。     

心脏神经症患者的心功能特点

目的:探讨心脏神经症患者的心功能特点.方法:采用心阻抗法检测46例心脏神经症患者和50例健康成年人的心功能各项指标.结果:心脏神经症患者的SV、CO、CI、HI和AC均明显低于健康对照组(P＜0.01),而TPR明显高于对照组(P＜0.01),而且心脏神经症患者的心室舒张功能显著低于正常对照组.结论:心脏神经症患者的心脏收缩和舒张功能均减退.     

Reducing the oxidative stress mediates the cardioprotection of bicyclol against ischemia-reperfusion injury in rats

Objective

To investigate the beneficial effect of bicyclol on rat hearts subjected to ischemia-reperfusion (IR) injuries and its possible mechanism.

Methods

Male Sprague-Dawley rats were intragastrically administered with bicyclol (25, 50 or 100 mg/(kg·d)) for 3 d. Myocardial IR was produced by occlusion of the coronary artery for 1 h and reperfusion for 3 h. Left ventricular hemodynamics was continuously monitored. At the end of reperfusion, myocardial infarct was measured by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and serum lactate dehydrogenase (LDH) level and myocardial superoxide dismutase (SOD) activity were determined by spectrophotometry. Isolated ventricular myocytes from adult rats were exposed to 60 min anoxia and 30 min reoxygenation to simulate IR injuries. After reperfusion, cell viability was determined with trypan blue; reactive oxygen species (ROS) and mitochondrial membrane potential of the cardiomyocytes were measured with the fluorescent probe. The mitochondrial permeability transition pore (mPTP) opening induced by Ca²⁺ (200 μmol/L) was measured with the absorbance at 520 nm in the isolated myocardial mitochondria.

Results

Low dose of bicyclol (25 mg/(kg·d)) had no significant improving effect on all cardiac parameters, whereas pretreatment with high bicyclol markedly reduced the myocardial infarct and improved the left ventricular contractility in the myocardium exposed to IR (P<0.05). Medium dose of bicyclol (50 mg/(kg·d)) markedly improved the myocardial contractility, left ventricular myocyte viability, and SOD activity, as well decreased infarct size, serum LDH level, ROS production, and mitochondrial membrane potential in rat myocardium exposed to IR. The reduction of ventricular myocyte viability in IR group was inhibited by pretreatment with 50 and 100 mg/(kg·d) bicyclol (P<0.05 vs. IR), but not by 25 mg/(kg·d) bicyclol. The opening of mPTP evoked by Ca²⁺ was significantly inhibited by medium bicyclol.

Conclusions

Bicyclol exerts cardioprotection against IR injury, at least, via reducing oxidative stress and its subsequent mPTP opening.     

Validation of the use of foreign gas rebreathing method for non-invasive determination of cardiac output in heart disease patients

INTRODUCTION In the arsenal of cardiac functional parameters,cardiac output(CO),cardiac index(CI),and strokevolume(SV)are potentially important determinantsof hemodynamics,the measurement of which relieson complicated and sometimes invasive techniques.In the case of congestive heart failure,non-invasivemethods to provide accurate measures of these pa-rameters during exercise stress testing would addsignificant objectiveness to the test result.This couldbe of considerable importance for …     

Study on the effect of doxorubicin on expressions of genes encoding myocardial sarcoplasmic reticulum Ca2+ transport proteins and the effect of taurine on myocardial protection in rabbits

To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits were injected with DOX , 8 rabbits with DOX and Tau, and 9 rabbits with normal saline. Cardiac function , concentration of calcium in cardiomyocytes (Myo[Ca2+]i), activity of SR Ca2+-ATPase(SERCA2a), level of SERCA2a mRNA and Ca2+ released channels(RYR2)mRNA were detected. The left ventricle tissues were observed by electron microscopy. The results showed that cardiac index, left ventricular systolic pressure, activity of SR Ca2+-ATPase and level of SERCA2a mRNA decreased , while Myo[Ca2+]i increased in DOX-treated rabbits. DOX could not affect the level of RYR2 mRNA. Tau intervention could alleviate the increase of left ventricular diastolic pressure, Myo[Ca2+]i and the decrease of SERCA2a mRNA induced by doxorubicin. The results suggested that downregulation of SERCA2a gene expression was an important mechanism of DOX-induced cardiomyopathy and that Tau could partially improve the heart function by reducing calcium overload and alleviating downregulation of SERCA2a mRNA.     

肢体缺血预处理对大鼠坏死心肌的保护作用

目的:研究肢体缺血预处理(LIP)对大鼠缺血再灌后心脏损伤的影响。方法:采用反复捆绑后肢造成缺血预适应的方法,观察其对心肌缺血再灌后梗死面积和形态学改变的影响,对心肌CK-MB和cTn-I的影响,以及对抗氧化物酶的影响。结果:与缺血再灌组比较,预处理能明显降低心肌梗死面积,减轻心肌细胞的损害,减少心肌酶的漏出并能提高SOD的活性。结论:LIP对心肌损伤具有保护作用。     

Hemodynamic changes in depressive patients

Objective： This study is aimed at exploring the relationship between hemodynamic changes and depressive and anxious symptom in depression patients. Methods： The cardiac function indices including the left stroke index （LSI）, ejection fraction （EF）, heart rate （HR）, diastolic pressure mean （DPM）, systolic pressure mean （SPM）, left ventricle end-diastolic volume （LVDV）, effective circulating volume （ECV）, resistance total mean （RTM） and blood flow smooth degree （BFSD） were determined in 65 patients with major depressive disorders and 31 healthy normal controls. The clinical symptoms were assessed with Hamilton depression scale （HAMD） and Hamilton anxiety scale （HAMA）. Results： In patients with depression without anxiety, LSI, EF, LVDV, DPM, SPM, ECV, BFSD were significantly lower than those in controls, while RTM was higher than that in controls. Patients with comorbidity of depression and anxiety showed decreased LVDV, ECV, BFSD, and increased HR in comparison with the controls. The anxiety/somatization factor score positively correlated with LSI, EF, LVDV, but negatively correlated with RTM. There was negative correlation between retardation factor score and DPM, SPM, LVDV. Conclusion： The study indicated that there are noticeable changes in left ventricle preload and afterload, blood pressure, peripheral resistance, and microcirculation in depressive patients, and that the accompanying anxiety makes the changes more complicated.     

Study on the effect of doxorubicin on expressions of genes encoding myocardial sarcoplasmic reticulum Ca~( 2+) transport proteins and the effect of taurine on myocardial protection in rabbits

ＩＮＴＲＯＤＵＣＴＩＯＮＤｏｘｏｒｕｂｉｃｉｎ(ＤＯＸ)ｉｓａｋｉｎｄｏｆａｎｔｈｒａｃｙ ｃｌｉｎｅｓａｎｔｉｂｉｏｔｉｃｓｗｈｏｓｅａｎｔｉｎｅｏｐｌａｓｔｉｃｓｐｅｃｔｒｕｍｉｓｂｒｏａｄａｎｄｅｆｆｅｃｔｉｓｓｔｒｏｎｇ.Ｉｔｈａｓｇａｉｎｅｄｗｉｄｅ ｓｐｒｅａｄｕｓｅｉｎｔｈｅｔｒｅａｔｍｅｎｔｏｆｃｈｉｌｄｈｏｏｄｌｅｕｋｅ ｍｉａａｎｄｓｏｌｉｄｔｕｍｏｒｓ.Ｈｏｗｅｖｅｒ,ｉｔｓｃｌｉｎｉｃａｌｕｓｅｉｓｌｉｍｉｔｅｄｂｙｉｔｓｃａｒｄｉｏｔｏｘｉｃｉｔｙ .Ｔｈｅｃａｌｃｉｕｍｏｖｅｒ…     

淋巴液对不同状态大鼠左心室内压的影响

淋巴液对正常血压大鼠的平均动脉压[MAP]、左室收缩压[LVSP]及左室舒张末压[LVEDP]与生理盐水对照组各项指标相比无显著差异[P>>0.05];而对失血性休克大鼠的MAP、LVSP具有显著回升作用[P<0.01],而对休克时LVEP的恢复无明显作用[P>0.05]。提示:淋巴液只能提高休克心脏的收缩功能,在低血容量情况下对休克心脏的舒张功能无明显影响,对正常心脏的收缩和舒张功能均无明显影响。