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Objective To investigate the relationship between multi‐dimensional myocardial strain and global cardiac function in different stages of cardiac dysfunction in spontaneously hypertensive rats ( SHR ) by two‐dimensional strain echocardiography . MethodsAccording to cardiac function measurements ,SHR of 28 to 102 weeks were divided into 3 groups :Normal group[ Group A , normal left ventricular ejection fraction( LVEF) and left ventricular end‐diastolic pressure( LVEDP) , n ＝13] ,diastolic dysfunction group ( Group B , normal LVEF but increased LVEDP , n ＝24) ,and systolic dysfunction group ( Group C ,decreased LVEF and increased LVEDP , n ＝ 17 ) ,with WKY rats at similar weeks of age as controls ( group a , n ＝ 7 ;group b , n ＝ 12 ; and group c , n ＝ 16 ) . Morphological parameters of left ventricular were measured by echocardiography . Using EchoPac workstation ,systolic peak longitudinal strain ,circumferential and radial strain were calculated at the left ventricular middle levels . Extracellular collagen content was observed histologically . Results Left atrial dimension increased in group B and larger in group C ,and dilated left ventricular and thickened wall were only found in group C .Systolic peak longitudinal strain of group B was significantly lower than group A and group a ( all P ＜ 0 .05 ) ,and deteriorated in group C( P ＜ 0 .05 ) ,while systolic peak circumferential and radial strain and LVEF were only significantly decreased in group C ( all P＜ 0 .05 ) ,w hile there was no significant difference between Group A and Group B( all P ＞0 .05) . Collagen content in endocardial and mid‐layer myocardium increased in group B and C , and increased epicardial collagen occurred in group C . Systolic peak longitudinal strain , circumferential and radial strain were correlated positively with LVEF( r ＝0 .65 ,0 .80 ,0 .80 ,all P ＜0 .01) . Conclusions In SHR ,systolic peak longitudinal strain obtained by echocardiography is decreased in the period of diastolic dysfunction ,w hile the damage of systolic peak circumferential and radial strain leads to the systolic dysfunction .
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Objective@#To investigate the relationship between multi-dimensional myocardial strain and global cardiac function in different stages of cardiac dysfunction in spontaneously hypertensive rats (SHR) by two-dimensional strain echocardiography.@*Methods@#According to cardiac function measurements, SHR of 28 to 102 weeks were divided into 3 groups: Normal group[Group A, normal left ventricular ejection fraction(LVEF) and left ventricular end-diastolic pressure(LVEDP), n=13], diastolic dysfunction group (Group B, normal LVEF but increased LVEDP, n=24), and systolic dysfunction group (Group C, decreased LVEF and increased LVEDP, n=17), with WKY rats at similar weeks of age as controls (group a, n=7; group b, n=12; and group c, n=16). Morphological parameters of left ventricular were measured by echocardiography. Using EchoPac workstation, systolic peak longitudinal strain, circumferential and radial strain were calculated at the left ventricular middle levels. Extracellular collagen content was observed histologically.@*Results@#Left atrial dimension increased in group B and larger in group C, and dilated left ventricular and thickened wall were only found in group C. Systolic peak longitudinal strain of group B was significantly lower than group A and group a(all P<0.05), and deteriorated in group C(P<0.05), while systolic peak circumferential and radial strain and LVEF were only significantly decreased in group C (all P<0.05), while there was no significant difference between Group A and Group B(all P>0.05). Collagen content in endocardial and mid-layer myocardium increased in group B and C, and increased epicardial collagen occurred in group C. Systolic peak longitudinal strain, circumferential and radial strain were correlated positively with LVEF(r=0.65, 0.80, 0.80, all P<0.01).@*Conclusions@#In SHR, systolic peak longitudinal strain obtained by echocardiography is decreased in the period of diastolic dysfunction, while the damage of systolic peak circumferential and radial strain leads to the systolic dysfunction.
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Objective To investigate the value of two-dimensional echocardiography (2DE) in detecting left ventricular regional wall motion abnormality (RWMA) in non-ST-elevation myocardial infarction (NSTEMI) by contrast with coronary angiography (CAG).Methods Totally 68 cases of NSTEMI patients (NSTEMI group)and 50 cases of normal peoples (normal group)were collected.2DE dynamic image and CAG results were comparatively analyzed in two groups.Left ventricular RWMA of all patients were observed through multi-section dynamic images by 2 experienced echocardiographic physicians.Left ventricular wall motion abnormalities were determined according to the 16 segment method of the American Society of echocardiography (ASE).2DE-RWMA was positive if there were one or more segments of motion abnormalities.All NSTEMI patients underwent CAG 2 days after 2DE examination,CAG was positive if the degree of coronary artery stenosis was more than 50％.Results In 68 NSTEMI patients,66 cases were CAG positive and 2 cases were negative,35 cases were 2DE-RWMA positive and 33 cases were negative.Taking CAG as a gold standard,the sensitivity,specificity and accuracy,positive predictive value and negative predictive values of 2DE-RWMA in diagnosis of NSTEMI were 51.52％ (34/66),50.00 ％ (1/2),51.47％ (35/68),97.14％ (34/35),3.03 ％ (1/33).Compared with the 2DE-RWMA negative patients,the rate of three branches of coronary artery stenosis in 2DE-RWMA positive patients was higher (62.85％ vs 39.39％,P＜0.05),the degree of coronary artery stenosis that reached 90％-99％ was higher (68.57％ vs 48.48％,P＜0.05).Conclusion The sensitivity of 2DE is low of NSTEMI in detecting the left ventricle RWMA.The degree of coronary artery stenosis is probably serious if 2DE-RWMA is positive,which is helpful for preliminary clinical judgment.
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Background Left atrium size was reported as a marker for ventricular diastolic dysfunction and predictive risk factors for cardiovascular disease.Objective To analyze the relations between left atrial(LA) size and left ventricular(LV) diastolic function echocardiographically in rabbit model with LV dysfunction while with normal LVEF.Methods LV pressure overloaded animal model was established by abdominal aorta constriction in 18 New-Zealand rabbits(model group) which developed LVH with normal EF with 8 healthy rabbits as normal controls.LA dimension and volume(LAD,LAV),left ventricular dimension(LVD) and wall thickness(IVST,PWT),Transmitral inflow E and A,and mitral annulus velocities Ea and Aa were determined by echocardiography.LVEDP was measured within 24 hours after echo examination by catheterization.Results ①Increased LVD,IVST,PWT and LA size were found in model group(P