One hundred cases of tetralogy of Fallot, confirmed by surgery, had been studied by two-dimensional echocardiography (2-DE). The preoperative diagnostic accuracy of the 2-DE was found to be 95%. All of VSDs, right ventricular hypertrophies and narrowings of the right ventricular "outflow tracts were demonstrated by the 2-DE. 97% of the over-riding aorta and 97.5% of the deformities of pul-monic valves were visualized. Contrast echocardiography demonstrated that moderate to massive amounts of contrast media were shunted from the right ventricle to the aorta during systole in 93% of the cases while the absence of contrast medium in. or the amount of such medium gaining access to the main pulmonary artery could be clearly visualized. Thus the contrast study was quite helpful in identifying pulmonary atresia and in quantitating the degree of pulmonary stenosis. Factors affecting the correct diagnosis of tetralogy of Fallot were then discussed.

Mitral effective regurgitant orifice area was measured by using color Doppler flow convergenee method,and its value on quantilarian of mitral insufficiency Was evaluated.The results showed that the parameter was correlated well with regurgitant volume,regurgitant fraction,color Doppler jet beginning width and jet area(r=0.89、0.84、0.82 and 0.67 respectively,P<0.001～0,0001).The accurate rate in differentiating mild and moderate from severe mitral regurgitation was 95.7% with the effective regurgitant orifice area≥30mm2.The effective regurgitant orifie area is a good parameter in quantification of naitral insufficiency.

The value of flow convergence and jet parameters in quantification of mitral regurgitation was estimated.The resultS showed that there were excellent correlations between mitral regurgitant flow convergence volume and mitral regurgitant volume,regurgitant fraction(r=0.87～0.93,P<0.0001).The correlations between jet parameters and regurgtant volume,regurgitant fraction were different,jet beginning width:r=0.88 and 0.81(P<0.0001),jet area : r=0.72 and O.50 and 0.61(P<0.05)and the ratio of jet area to left atrial area:r=0.27 and 0.29(P>0.05).The accurate rates of regurgitant flow convergence volume and jet beginning width in differentiating the grades of mitral regurgitation were 91.3～95.7%and 82.6～95.7%respectively.Mitrai regurgitant flow convergence volume is an accurate and reliable parameter in the quantification of mitral regurgitation.Jet parameters are of relative value in semiquantitation of mitral regurgitation,especially the jet beginning width.

Flow convergence is a new method of color Doppler flow quantification.The effect of instrumental settings on flow convergence was investigated in an in-vitro model.The result showed that the flow convergence volume increased from 1.67±1.01 l/min to 2.20±1.35～2.30±1.43 l/min(P< 0.0001)when aliasing limit(same concept as Nyquist frequency)was changed from 23 cm/s to 12cm/s. There was no significant effect on flow convergence volume with the change of other instrumental settings,including Color gain,frame frequency,paket size,transmit power,transducer frequency,etc. Color Doppler flow convergence is influenced by aliasing limit.mainly because that the isovelocity surfaces in acceleration region developed by different aliasing limits are not always in the shape of hemisphere.The result suggested that besides the selection of aliasing limit fits to a hemispherical isovelocity surface,flow convergence is rarely affected by the other instrumental settings,and therefore is a relatively stable parameter of flow quantification.

Objective　To assess the value of real-time myocardial contrast enhancement imaging (real-time MCE) on acute myocardial infarction.Methods　Eight open-chest canine models of myocardial infarction were established by ligating left anterior descent branch of coronary artery (LAD) on level after first diagonal branch. The real-time MCE, using intravenous instillation of a new kind of Perfluorocarbon contrast agent， were performed before the occlusion, 1 hour and 3 hours after the occlusion. The myocardial contrast agents perfusion and wall motion was observed on the middle of papillary muscles scan plane.Results　The real-time MCE showed not only the black aridity of contrast agents but also the wall motion abnormality 1 hour and 3 hours after the occlusion. In comparison with pathology, the defects of contrast perfusion were larger than the stained infarction zones. In addition, the flash contrast imaging revealed the reperfusion defect of adjacent zones.Conclusions　With the ability of showing the myocardial microcirculation and wall motion function simultaneously, the real-time MCE makes MCE exam significantly easier to perform. Finally, flash contrast imaging will be the cornerstone upon which perfusion quantification will be built.

Objective To study the ultrasound-guided treatment by real-time biplane imaging in animals and patients. Methods In 6 dogs gallbladders were substituted as hepatic cysts. The shapes of gallbladders and spatial positions of needle tips in gallbladders were studied by real-time biplane imaging before and during treatments. During treatments of 3 renal cysts the changes of cysts and the spatial relations between needle tips and renal cysts were observed to confirm that the needle tips were always in the cysts. In 2 cases of hepatocellular carcinoma boiloff of the tissue around the antenna was observed by real-time biplane imaging during microwave coagulation. Results It was rapid and convenient to acquire the shape information of objects and locate the position of puncture by real-time biplane imaging. And it was more convenient to observe the spatial relation between needle tips and objects of treatment than by conventional single-plane imaging. Conclusions The method of real-time biplane imaging has great advantages in ultrasound-guided treatment.

Objective To study the velocity pattern of ischemic myocardium change during systolic phase by Doppler tissue imaging(DTI). Methods Twenty-three dogs were investigated as two groups. In 13 open-chest dogs as group A, regional wall motion abnormalities were induced by occluding branches of left circumflex coronary arteries(LCX). Left ventricular(LV) wall systolic velocity patterns at the mid-wall portion of the middle of LV posterior walls in the short-axis direction were recorded with DTI before and after artery occlusion. Ten dogs as group B were operated to occlude branches of LCX. Before and one week after operation the same parameters were recorded by transthoracic method. Results There were positive velocity peak(IVC 1), negative velocity peak(IVC 2) during isovolumic contraction and positive velocity peak(S) during ejection in DTI spectra of all normal LV posterior walls. The peak velocities of IVC 1 and S decreased significantly, but the peak velocity of IVC 2 increased significantly after occluding branches of LCX in both groups (P

Objective To investigate the feasibility of gene delivery to the ischemic myocardium of rabbits by ultrasound-mediated destruction of microbubbles. Methods A ligation model of left circumflex branch coronary artery was established in 48 rabbits. Three days after ligation, the mixture of gene and microbubbles was infused into the vein of rabbits with or without simultaneous ultrasound. Additional controls included ultrasound of microbubbles that did not contain gene, gene alone, gene plus ultrasound,and blank control. Rabbits were killed after two weeks and examined for the expression of vascular endothelial growth factor(VEGF). Results The hearts of five rabbits that underwent ultrasound-mediated destruction of microbubbles containing gene showed VEGF expression in ischemic myocardium.None of the control animals showed VEGF expression. Conclusions Ultrasound-mediated destruction of microbubbles is a promising method for the delivery of bioactive agents to the heart.

Objective To study the characteristics of calcific valvular heart disease (CVHD) with the aid of echocardiography. Methods Nine thousand and seventeen patients over 50 year-old who had received transthoracic echocardiographic examination were enrolled in the study. Diagnosis of CVHD was made with 2 dimension, M-mode and color Doppler echocardiography. General state of health, clinical manifestation and history of CVHD patients were also analyzed. Results Five hundred and seventy-four cases of CVHD were diagnosed and the characteristics of CVHD were observed. The diagnostic rate increased as the age increased. There was no significant difference between male and female. The calcified regions were commoner in aortic valves than in mitral valves, more frequent in non-coronary valves than in right or left coronary valves, and more frequently seen at tips of aortic valves and annuli of mitral valves than in other parts. The size of calcific plaques was usually between 3 and 10mm. Hemodynamic changes could be found in some patients. History of hypertension, coronary artery disease, and arteriosclerosis of the aorta were often found in these patients. Conclusions Echocardiography can be used to evaluate the position of calcification, size of calcification area, and degree of valvular stenosis or insufficiency, thus offers useful information for early diagnosis and treatment, and prognosis of CVHD in clinic.

Objective To explore the incidence and predisposing factors of coronary heart disease (CHD) among the patients with different types and extent of calcified valvular heart disease (CVHD). Methods 574 patients with CVHD diagnosed by echocardiography were divided into mild and severe groups based on the hemodynamic changes. The differences of incidence and predisposing factors of coronary heart disease between the two groups were compared. Results Ninety-seven cases of CVHD were categorized as having severe lesion, including aortic stenosis subgroup (AS group), aortic insufficiency subgroup (AI group) and mitral valve subgroup (MV group). All other patients were having mild lesions. There was no significant difference in blood pressure, blood lipid, fasting blood glucose, age and incidence of CAD, incidences in hypertension, hyperlipidemia and diabetes mellitus between two groups. Conclusions Mild CVHD showed similar prognostic value as that of severe CVHD, therefore it should not be ignored.