Objective To evaluate the difference of myocardium strain between myocadial infarction and ventricular aneurysm (VA) by two-dimensional speckle-tracking imaging in rabbits.Methods 26 healthy New Zealand white rabbits were enrolled in this study,6 were put into the control group and 20 in the experimental group.models of myocardial infarction concomitant with VA were prepared by the ligation of the middle segment of left anterior descending artery and left circumflex artery.At 4 weeks after the procedure,according to the pathological inspect and echocardiography for whether VA formed,the experimental animals were divided into the VA group and the myocadial infarction group.Echocardiography was performed to measure the LV cavity size and cardiac function.Radial strain rate (SrR) and circumferential strain rate(SrC) indexes were measured by 2D-STI software for each animal at the level of apex in left ventricular short-axis view,and then calculated the strain rate decrease percentage in each segment.Results 1)Compared with the control group,SrR-S,SrR-E,SrR A,SrC-S,SrC-E,SrC-A in all segments were reduced significantly in the VA group and the myocadial infarction group (P ＜ 0.05),the VA group was the most significant.2)Compared with the myocadial infarction group,the strain rate decrease percentage of SrR-S,SrR-E,SrR-A,SrC-S,SrC-E,SrC-A in all segment had significant in the VA group.Comparison between the each section,the strain rate decrease percentage of SrR-Santerior wall,SrR-Sateral wall,SrC-Santerior wall,SrC-Slateral wall were the most significant.3)There were the tighter relationship between the strain rate decrease percentage of SrR-Santerior wall,SrC-Santerior wall,SrR-Slateral wall,SrC-Slateral wall and left ventricular ejection fraction (r =0.82,0.72,0.75,0.71,repectively,all P ＜ 0.05).4) The ROC curve analysis showed that when the strain rate decrease percentage was 60％ as the critical point,the strain rate decrease percentage of SrC-Santerior wall,SrC-Slateral wall,SrR-Santerior wall,SrR-Slateral wall had a sensitivity of 83.30 ％,84.40％,83.30％,67.70％％ and a specificity was 73.60％,78.20％％,69.70％,83.30％ for prognosis ventricular aneurysm,repectively.Conclusions After ventricular aneurysm formation,anterior and lateral wall myocardial strain were give priority to the myocardial mechanics reconstruction,thus systolic myocardial strain rate decrease percentage can be important indicator of infarction myocardial developing into ventricular aneurysm.

Objective To construct the uItrasound microbubbIes co-carrying recombinant adenovirus containing stromal cell derived factor 1 (SDF-1α) and bone morphogenetic protein 2 (BMP2),and to study the maximum efficiency of carrying adenovirus and the optimum proportion of double gene combined with ultrasound contrast agents.Methods Microbubbles were combined separately with recombinant adenovirus co-expression of enhanced green fluorescent protein and SDF-1α(pAd-EGFP/SDF-1α) as well as red fluorescence protein and BMP2 (pAd-RFP/BMP2) via biotin-streptavidin method,and the maximum efficiency of carrying DNA in microbubbles was detected.Three microbubbles with binary vectors were prepared by blending the two above-mentioned pAd at different ratio (1 ∶1,1 ∶ 2,2 ∶ 1) into the microbubbles.The microbubbles with binary vectors were evaluated though physiochemical properties,fluorescence microscope and flow cytometry to test the carrying rate of DNA in microbubbles.Results There was no significant difference in PH,average diameter and concentrations between targeted microbubbles and control group (P ＞0.05).The carrying efficiency of DNA increased with virus loads in microbubbles,but lowered if further increasing virus amount after reaching saturation.When the proportion of binary vectors and microbubbles was 1 ∶ 1,its efficiency of carrying SDF-1α gene and BMP-2 was approximately equal,and flow cytometry demonstrated that the positive rate of microbubbles labeled by both fluorescein isothiocyanate(FITC) and rhodamine was (65.6 ± 0.5)％.However,it was (59.0 ± 2.3)％ when their proportion was the 2 ∶ 1,which was significantly lower than those when other two proportions (1 ∶ 1 and 1 ∶ 2).Under the fluorescence microscope,the targeted microbubbles were equally surrounded by bright green or red fluorescence.Conclusions Ultrasound microbubbles of double genes carrying EGFP/SDF-1a and RFP/BMP2 is made successfully via biotin-streptavidin method.The optimal proportion of combining microbubbles with double gene is 1 ∶1,which can reveal the optimum load rate and stable combination.

Objective To evaluate the applied values of echocadiography in closing membranous ventricular septal defects (VSD) with the Amplatzer devices. Methods The VSD were closed by transcatheter Amplatzer closure devices in nine patients. The patients′ age ranged between 15-45 years old,mean (26?10) years old. The VSD diameter was measured from 3 to 15 mm. Seven patients were guided by transthoracic echocardiography and 2 patients by transesophageal echocardiography. Results All VSD were successfully closed by the Amplatzer devices, without complications. The device size ranged from 6 to 18 mm. No residual shunt and complication were detected by the echocadiography in intraoperation and 3 or 4 days after operation. Conclusions Echocardiography plays an important role in closing VSD with Amplatzer device, not only in intraoperative guidance and monitor, but also in post-operative follow up study.

Objective To evaluate the systolic and diastolic function in hypertrophic segments by myocardial strain rate imaging in the patients with hypertrophic cardiomyopathy (HCM).Methods Ten patients with HCM in the mid segment of the ventricular septum and 20 age-matched healthy controls were included.The myocardial strain rate (SR) curves in bas,mid and apical segments were respectively acquired on the left ventricular septum longitudinal axis position for all the participants,and the SR curves of endocardial,mid-myocardial,epicardial layers in mid segment were also acquired.The SR values including the peak systolic SR,the peak early-diastolic SR,the peak late-diastolic SR were respectively measured,the left ventricular eject fraction (EF) and the Doppler transmitral filling velocities (E and A values) were also measured.Results SR values measured from the hypertrophic segments were significantly lower than those from the corresponding segments of the septum in control group (P

Objective To evaluate left atrial (LA) function by real-time three-dimensional echocardiography (RT-3D) and speckle tracking imaging (STI) after circumferential ablation of pulmonay vein ostia for atrial fibrillation guided by carto mapping system. Methods Thirty patients who had ablation procedure for paroxysmal atrial fibillation were accepted echocardiography to estimate the LA function at pre-operation,3 days and 3 months of post-operation. The LA maximal, minimal and pre-systolic volume (LAVmax, LAVmin and LAVp), LA passive ejection fraction (LAPEF), LA active ejection fraction (LAAEF) were measured by RT-3DE respectively. The strain rate curve was acquired in each LA segment (anterior, posterior, lateral, inferior and septal) by STI. Systolic strain rate (SRs), early diastolic strain (SRe) and late diastolic strain rate(SRa) of each left atrial segments were measured. Results Comparing with preoperative,3 days post-ablation SRs,SRe and SRa decreased significantly in each wall of LA. After 3 months,SRa and SRe in anterior, inferior and septal were significantly improved, however, SRs showed no significant difference. LAVmax and LAVpre were significantly decreased. LAPEF and LAAEF were significantly improved. Conclusions The patients with circumferential pulmonary vein ablation were in a deterioration after three days. The pump function and conduit functions of left atrial were increased after 3 months.

Objective To study the change of thrombosis in rabbits arteries by electron microscope after thromb was lyses by urokinase targeted microbubbles.Methods A total of 24 rabbits with plateletrich thrombi in the femoral artery were randomized into 4 treatment groups (n = 6) :(1) ultrasound alone (US) ; (2) urokinase alone (UK); (3) ultrasound, non-targeted microbubble and urokinase (US + M + UK) ;(4) ultrasound, platelet-targeted microbubble and urokinase (US + R + UK).Urokinase targeted microbubbles were in conjunction with the surface of commercial microbubbles (SonoVue) by direct conjugation method.US was simultaneously applied transcutaneously over the thrombus up to 30 min.The thrombolytic effect was based on ultrasound, blood flow and histological observations at 120 min post treatment.Results US + R + UK group was completed recanalization (P ＜ 0.001).Scanning electron microscope examination showed thrombosis of the fiber network structure damage.Conclusions The main electron microscope change of RGDS urokinase targeted microbubbles dissolve thromb is thrombus fibrin network structure damage and fibrin dissolution.

BACKGROUND:Stromal cel-derived factor-1 (SDF-1) is one of the most powerful chemokines in myocardial infarction region and plays a particularly pivotal role in the homing of stem cels to an injured myocardium and promoting angiogenesis. On the other hand the microbubble and acoustics active substances carrying targetable ligands can be prepared into targeted ultrasound contrast agents that can be combined with living cels used for molecular imaging. The key of ultrasonic molecular imaging is to find imaging targets, and to successfuly prepare targeted ultrasound contrast agent which can be combined with the imaging target specificaly and efficiently. OBJECTIVE:To prepare and evaluate targeted microbubble contrast agents with SDF-1 monoclonal antibody. METHODS:Targeted microbubble contrast agent with SDF-1 monoclonal antibody was prepared using the biotin-streptavidin method. The physiochemical properties of targeted microbubble contrast agent were evaluated by appearance, pH, particle diameter, optical and fluorescence microscope and flow cytometry test. Four minipigs underwent ligation of the left anterior descending coronary artery to complete the establishment of acute myocardial infarction model, and another two minipigs were subject to thoracotomy but no ligation of the coronary artery. Then, al animals were injected with microbubble contrast agents. The stability of microbubbles was assessed by immunofluorescence testin vivo. RESULTS AND CONCLUSION:SDF-1 and microbubbles were combined by biotin-streptavidin method.In vitro appearance of the contrast agent was translucent yelow or green, and stratified after standing. pH vaule was 7.02±0.12 for non-targeted contrast agent and 6.10±0.19 for targeted microbubble contrast agent. Under the fluorescence microscope, the distribution and size of targeted microbubbles were uniform, and the microbubbles were surrounded by bright and ring shaped green fluorescence that had no changes after highly shaking. The diameter of microbubbles was (2 422.62±238.82) nm after carrying the SDF-1 antibody. Flow cytometry results showed that the carrying rate of targeted contrast agents was stable in different periods.In vivo test showed that targeted microbubbles gathered in vascular endothelial cel surface after acute myocardial infarction. These findings indicate that the targeted microbubble contrast agent carrying SDF-1 monoclonal antibody prepared by biotin-streptavidin method can be combined with vascular endothelial cels, and the binding rate is high and stablein vitro.

Objective To measure the parameters of mitral valve leaflets and mitral annulus in patientswithmildmitralregurgitation( MR )byreal timethree-dimensionaltransesophagealechocardiography (RT-3D-TEE),and explored the mechanism of MR.MethodsFifty-seven MR subjects were selected and twenty-eight subjects without mitral regurgitation were served as control group,all subjects were examined by RT-3D-TEE and acquired image,mitral valve quantification (MVQ) software was used for post-processing.Mitral annulus parameters (H/DAIPm,E2D,θAv-Mv,mitral annulus θnpa) and mitral valve leaflets parameters(A3DE,L2DAIPm,VA1-3tentVp1-3tentVtentHtentθnpa ) at the end of systolic were measured.The results of two groups were compared,and the most affected parameters to mild mitralregurgitation were selected.Results Compared with control group,VA3tent was decreased,mitral annulus θnpa and L2DAIPm increased,and the mitral valve leaflets θnpa was independently correlation factor of mild mitral regurgitation.ConclusionsThe mitral annulus geometry to flat in subjects with mild MR,the mitral valve local area is increased in subjects with mild MR,the mitral valve leaflets θnpa is independently correlation factor of mild mitral regurgitation.

ObjectiveTo evaluate the influence on left ventricular(LV) twist,and the relationship between LV twist and function in the rabbits with ventricular aneurysm formed after myocardial infarction by two-dimensional ultrasound speckle tracking imaging.MethodsTwenty-six healthy rabbits were divided into two groups,six as control group,twenty as experimental group.The model of myocardial infarction and ventricular aneurysm were established by ligaturing left anterior descending coronary artery and left circumflex artery.After four weeks,according to the pathological examination of whether ventricular aneurysm formed or not,the experimental group was divided into myocardial infarct group and ventricular aneurysm group.Echocardiography was performed to measure rotations (at the levels of mitral annulus and apex in LV short-axis view),LV twist,left ventricular cavity size and function.ResultsCompared with the myocardial infarct group,LV end-diastolic diameter(LVEDD) and LV end-diastolic volume(LVEDV) were larger in the ventricular aneurysm group,but LV ejection fraction (LVEF),LV fractional shortening (LVFS),apical rotation and LV twist were lower in the ventricular aneurysm group than the myocardial infarct group.Both apical rotation and LV twist had shown a great correlation with LVEF.The conclusion was also shown in the ROC curve that sensitivity and specificity of diagnosis cardiac dysfunction were 76.9％ and 80.0％ respectively when the apical rotation was 1.21°.Conclusions There was a closely relationship between the change of apical rotation and the LV systolic function.When the apical rotation dropped to 1.21°,an apparent decline of LV systolic function was implied.