Systematical quantitative evaluation of left ventricular mechanical dysfunction in patients with cirrhosis using ultrasonic layer-specific strain imaging / 中华超声影像学杂志

Objective:To assess the left ventricular (LV) myocardial mechanical dysfunction in patients with cirrhosis using ultrasonic layer-specific strain imaging and to explore its value in clinical application.Methods:A total of 80 consecutive cirrhosis patients without cardiovascular diseases were prospectively enrolled from October 2020 to March 2021 in Sichuan Provincial People′s Hospital, 39 of whom were assigned to the compensated group and 41 were assigned to the decompensated group according to the occurrence of portal hypertension. Forty-three healthy volunteers during the same period were randomly recruited as the control group. Transthoracic echocardiography was performed to assess the LV configuration and functional parameters. LV global longitudinal strain in endocardial, middle and epicardial myocardium (GLSendo, GLSmid, GLSepi), and longitudinal strain (LS) in basal, middle and apical segments, and peak strain dispersion (PSD) were obtained using ultrasonic layer-specific strain imaging. ΔLS was calculated by the formula of GLSendo-GLSepi. Then, the differences of related parameters among three groups were compared.Results:①Conventional echocardiography: compared with the control group, the interventricular septum end-diastolic thickness (IVSTd), left ventricular posterior wall end-diastolic thickness (LVPWd), left ventricular mass (LVM) and LVM index (LVMI) were increased in compensated and decompensated groups (all P<0.05), while no significant differences in conventional echocardiographic parameters were identified between the two cirrhosis groups (all P>0.05). ②Global layer-specific strain: compared with the control group, GLSendo, GLSmid, GLSepi and ΔLS were decreased and PSD was increased in compensated and decompensated groups (all P<0.05); Moreover, the decompensated group showed a more impaired GLSendo, GLSmid and GLSepi than compensated group (all P<0.05), whereas there were no significant differences of ΔLS and PSD between the two groups(all P>0.05). ③Segmental layer-specific strain: compared with the control group, LS values of three layers in compensated and decompensated groups were reduced at basal, middle and apical levels (all P<0.05); Compared with the compensated group, LS values of three layers in decompensated group tended to be reduced at above there levels, but only apical segments had significant differences (all P<0.05). Conclusions:There are different degrees of LV mechanical dysfunction in patients with variable severity of cirrhosis. Ultrasonic layer-specific strain imaging has the potential to quantitatively assess the state of cardiac involvement in patients with cirrhosis and to provide visual evidence for the early and accurate diagnosis of myocardial injuries.

Effects of different ultrasound power application on left ventricular transmural displacement in vivo open‐chest Beagle canines / 中华超声影像学杂志

Objective To evaluate left ventricular ( LV ) myocardial mechanical transmural longitudinal displacement ( LD ) and radial displacement ( RD ) with contrast agent and different power irradiation in open‐chest Beagle canines by ultrasound velocity vector images ( VVI) workstation . Methods T he anesthetized open‐chest Beagle canines were assigned into two groups randomly :Group A ( n ＝6) for baseline ,diagnostic ultrasound power irradiation ( 300 mW) 5 min ,combined with contrast agent irradiation 5 min and contrast agent 20 min conditions ; Group B ( n ＝ 6 ) for baseline and intensity ultrasound irradiation ( 1 W ,2 W and 3 W ,5 min respectively) conditions . T he standard short‐axis and long‐axis gray‐scale view s during three complete cardiac cycles in open‐chest Beagle canine models were acquired . T he peak LD subendomyocardium ( LD‐subendo) ,LD subepimyocardium ( LD‐subepi) ,RD subendomyocardium ( RD‐subendo) and RD subepimyocardium ( RD‐subepi ) of LV were analyzed using a dedicated Syngo VVI method . Results In group A ,the LV LD‐subendo ,LD‐subepi ,RD‐subendo and RD‐subepi in the most of segments showed increasing trend in diagnostic power irradiation ,contrast agent irradiation 5 min and contrast agent 20 min compared with baseline condition ,however the differences were not significant ( P ＞0 .05 ,respectively) . T he peak LD‐subendo and LD‐subepi ,RD‐subendo and RD‐subepi of LV in group A with the same condition were significant different ( all P ＜0 .05) . In group B ,LV LD‐subendo in ultrasonic power 3 W was lower than baseline condition ( P ＜ 0 .05 ) ,LV RD‐subendo was higher compared with baseline condition ( P ＜0 .05) . T he peak LD‐subendo and LD‐subepi ,RD‐subendo and RD‐subepi of LV in group B with the same condition were significant different ( all P ＜ 0 .05) . Conclusions On ultrasonic power 3 W ,LV LD‐subendo is decreased resulting to negative inotropic effect and RD‐subendo is increased to maintain the normal heart work .LV LD and RD on diagnostic ultrasound power irradiation 5 min , combined with contrast agent irradiation 5 min ,contrast agent 20 min conditions ,ultrasonic power 1 W and 2 W are not prominent changes .

Present status and trend of heart fluid mechanics research based on medical image analysis / 生物医学工程学杂志

With introduction of current main methods for heart fluid mechanics researches, we studied the characteristics and weakness for three primary analysis methods based on magnetic resonance imaging, color Doppler ultrasound and grayscale ultrasound image, respectively. It is pointed out that particle image velocity (PIV), speckle tracking and block match have the same nature, and three algorithms all adopt block correlation. The further analysis shows that, with the development of information technology and sensor, the research for cardiac function and fluid mechanics will focus on energy transfer process of heart fluid, characteristics of Chamber wall related to blood fluid and Fluid-structure interaction in the future heart fluid mechanics fields.

The mechanical characterization study of mitral annulus at different sites in normal adults using ultrasonic dual pulse-wave Doppler / 中华超声影像学杂志

Objective To define the mechanical features of mitral annulus at various sites,and to investigate the specific mechanics characterization at different mitral annulus sites in evaluation consequences of left ventricular function by dual pulse-wave Doppler (DPW) technology.Methods The DPW spectrums were obtained at lateral and aboral interval,anterior and inferior and posterior mitral annular from 112 normal adults.The peak systolic velocity (Sm),peak early diastolic velocity (Em),peak late diastolic velocity (Am),the beginning time of the peak and the time to peak were measured,and E/A,Em/Am,E/Em,left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) were computed.Results 1)Sm,Em,Am and Em/Am measured in the free wall annulus were significantly greater than measured in the interval annulus of mitral annular sites.However,E/Em was opposited (P ＜ 0.05).Sm of the posterior wall mitral annulus accelerated frist and experienced shortest duration in all the mitral annular sites (P ＜ 0.01).There were no significant differences of Em time parameters among different mitral annulus sites.Am of the beginning time and peak time in the free wall annulus were significantly longer than that in the interval annulus of anterior mitral annular sites.However,the acceleration time was opposited(P ＜0.05).2) Sm was correlated with LVEF and LVFS (r =0.243 and r =0.227,P ＜0.01) only at the posterior mitral annular site,Em/Am of anterior and posterior wall mitral annulus had the highest correlations with mitral orifice flow E/A(r =0.545 and 0.545 respectively,P ＜ 0.01).Conclusions There are significant differences among the mechanics patterns at different mitral annulus sites in normal adults.The mechanics characterization at different mitral annulus sites have different conclusions of left ventricular function.

An initial study of left intra-ventricular diastolic fluid dynamics in pre-diabetics using vector flow mapping / 中华超声影像学杂志

Objective To evaluate left intra-ventricular diastolic blood flow patterns and fluid dynamics in pre diabetics using vector flow mapping(VFM),and to explore the value of left intra-ventricular hydromechanics characteristics assessment of intracardiac flow by VFM with more sensitive indexes.Methods Forty four patients with type 2 diabetes,twenty-eight pre-diabetes patients and thirty-three normal volunteers underwent VFM to determine the left ventricular(LV) diastolic blood flow patterns and fluid dynamics.The two-dimensional color Doppler flow images data were acquired in standerd apical fourchamber view during 3 complete cardiac cycles.These images were analyzed using a dedicated off-line workstation.At different level (mitral annulus,papillary muscl and apex level),the diastole blood flow parameters of LV including flow velocity and volume,velocity gradients (△V),pressure gradients (△P),diastole flow volume,vortex intensity ( Ⅵ),vortex area ( VA),vortex radius (VA) were derived.Thedifferences of the above parameters were compared among the three groups.The correlationship between diastolic function parameters and LV hydromechanics indexes were analyzed.Results ① Compared to normal group and pre-diabetics group,the LV diastolic function parameters E/A and e/a in diabetics group were lower( P ＜0.01),with no differences for E/e( P ＞0.05).There were no significant diffrences of these indices between diabetics group and pre-diabetics group( P ＞0.05).②)Compared to normal group,the intraventricular peak flow velocity at basal level,△V and △P in diabetics group and pre-diabetics group were lower( P ＜0.01),but there were no significant differences of these indices between diabetics group and prediabetics group( P ＞ 0.05).③Compared to normal group,the diastolic positive volume at basal level in diabetics group and pre-diabetics group was lower ( P ＜0.01 ),but there was no significant differences of these indices between diabetics group and pre-diabetics group ( P ＞ 0.05).④ Compared to the normal group,the Ⅵ in diabetics and pre-diabetics group was decreased,but there were no significant differences ofthese indices between diabetics group and pre-diabetics group( P ＞0.05).The VA and VR in diabetics and pre-diabetics group were increased,but there were no significant differences of these indices between diabetics group and pre-diabetics group ( P ＞ 0.05).⑤ There were no correlationship between diastolic function parameters and LV hydromechanics indexes.Conclusions There is the same LV diastolic blood flow patterns and fluid dynamics existed in pre-diabetics as diabetics.VFM could be used as a new methods to demonstrate the early left intra-ventricular fluid dynamics damages in pre-diabetics patients.