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

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.

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 .

Objectives:To identify the two-dimensional speckle tracking imaging (2D-STI)-derived longitudinal strain indices that reflect the myocardial functional characteristics of patients with apical hypertrophic cardiomyopathy (AHCM). Methods:This retrospective study included 30 patients with typical AHCM diagnosed at the First Affiliated Hospital of Fujian Medical University from January 2015 to May 2019 (AHCM group),35 patients with essential hypertensive left ventricular hypertrophy (HTLVH group),and 45 healthy volunteers (normal control group) were also included.Two-dimensional echocardiography was used to measure the cardiac chamber size and wall thickness,and 2D-STI was used to analyze the longitudinal strain during the left ventricular systolic phase,the global longitudinal strain (GLS) and the longitudinal strain of the apical,mid,and basal segments (LSA,LSM,LSB) were assessed.The ratios of the apical to the overall and other segmental longitudinal strains were used as the apical relative longitudinal strain indices,including the apical to basal longitudinal strain ratio (ABLR,LSA/LSB),the apical to global longitudinal strain ratio (AGLR,LSA/GLS),and the apical to basal-mid segment longitudinal strain ratio (ABMLR,LSA/[LSB+LSM]). Results:GLS was significantly lower in the AHCM group and HTLVH group than in the normal control group (both P<0.05),and was similar between the AHCM group and HTLVH group (P>0.05).The LSA,LSM,and LSB were also significantly lower in the AHCM group and HTLVH group than in the normal control group,LSA decrease was more significant in the AHCM group as compared to the HTLVH group,while the HTLVH group was mainly characterized by a decrease in LSB,which was significantly lower as compared to the AHCM group (all P<0.05).Compared with the normal control group,the ABLR,AGLR,and ABMLR were significantly reduced in the AHCM group,while significantly increased in the HTLVH group (all P<0.05).The ROC curve showed that the AUC of ABLR,AGLR,ABMLR,and LSA was 0.873 to 0.916,using<1.28 as the cutoff value of ABLR,the sensitivity was 90.0％ and specificity was 88.7％ for diagnosing AHCM. Conclusions:The apical relative longitudinal strain indices can reflect the myocardial functional characteristics of AHCM patients,which are better than single apical longitudinal strain value.As the most representative indice,ABLR may be useful in distinguishing AHCM from left ventricular hypertrophy caused by other diseases,and can be used as a parameter for the evaluation of myocardial function damage in AHCM.

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.