ABSTRACT
Objective To assess the characteristics of left ventricular(LV) systolic dyssynchrony in patients with chronic heart failure (CHF) using two dimensional speckle-tracking imaging(2D-STI) and validate the correlation between LV systolic dyssynchrony and its ejection fraction (EF) measured by traditional two dimensional echocardiography. Methods Forty-two patients with CHF, which were divided into group CHF1 with 35% ＜EF≤50% and group CHF2 with EF≤35%, and 35 healthy subjects as control group were enrolled in this study. Two-dimensional echocardiography Simpson's method was used to measure EF of LV. The time from the onset of QRS complexes to systole peak strain rate from the longitudinal, radial and circumferential vectors(Tsrsl, Tsrsr, Tsrsc)was recorded and measured using 2D-STI, respectively. The standard deviation and the maximal temporal difference of Tsrsl, Tsrsr, Tsrsc (Tsrsl-SD,Tsrsr-SD,Tsrsc-SD,Tsrsl-diff,Tsrsr-diff, Tsrsc-diff)of 18 segments were calculated as indicator of LV systolic dyssynchrony. Results The indices of LV systolic dyssynchrony Tsrsl-SD,Tsrsl-diff, Tsrsr-SD, Tsrsr-diff,Tsrsc-SD,Tsrsc-diff in group CHF1 and CHF2 were significantly higher than those in the control group (P<0.05). Compared with group CHF1, those indices in CHF2 were significantly longer (P<0.05). Meanwhile, Tsrsl-SD, Tsrsr-SD, Tsrsc-SD(r = - 0.904～0.912, all P<0.05) and Tsrsl-diff, Tsrsr-diff, Tsrsc-diff(r = - 0.916～0.967, all P<0.01) had singnificantly negative correlations with LVEF, and the correlation coefficients between radial and circumferential 2D-STI dyssynchrony parameters and LVEF were higher than those between the longitudinal parameters and LVEF. Conclusions 2D-STI is a useful modality to evaluate the LV systolic asynchrony of the CHF and there is a good correlation between LVEF and the LV systolic dyssynchrony indices derived from 2D-STI.
ABSTRACT
Objective To probe into the clinical value of left atrial(LA) volme tracking method (LAVT) on the assessment of left atrial function in patients with hypertension. Methods Thirty-one patients with hypertension and 31 control subjects were involved. Images of apical two-chamber and four-chamber views were obtained by two-dimensional echocardiography. LA maximal volume (LAVmax), LA minimal volume (LAVmin), LA presystolic volume (LAVpre), systolic LA filling rate (dv/dtS), early diastolic LA emptying rate (dv/dtE) and late diastolic LA emptying rate (dv/dtA) were derived using LAVT. LA passive emptying volume(LAVp), LA passive emptying fraction(LAVpEF), LA active emptying volume(LAVa), LA active emptying fraction (LAVaEF), LA total emptying volume (LAVt), LA total emptying fraction(LAVtEF) were calculated. All volume measurements were corrected to body surface area (LAVI). Results There were significant differences in the LAVImax, LAVImin, LAVIpre, LAVpEF, LAVIa, LAVIt,dv/dtS, dv/dtA between hypertensive patients and control subjects(P <0.05~0.001), but no significant differences were found in the LAVp, LAVaEF, LAVtEF,dv/dtE between the two groups. The LAVImax has shown significant positive correlation with LAVIp, LAVIa and LAVIt(r = 0.588~0.812, P <0.001). LAVaEF has shown positive correlation with the LAVtEF(r = 0.833, P<0.001), whereas LAVpEF has not(r = 0.420, P <0.01). There was a significant positive correlation with LAVImax and LAVIpre(r = 0.908, P <0.001), LAVIpre and LAVIa(r = 0.689, P <0.001) ,dv/dtE and LAVIp(r = 0.690, P <0.001),dv/dtA and LAVIa(r = 0.600, P <0.001). Conclusions In hypertensive patients,left atrial reservoir function and booster pump function increase, while left atrial conduit function decreases. LAVT has a potential ability to evaluate left atrial function.
ABSTRACT
Objective To evaluate left atrial(LA) function in patients with prophase type 2 diabetes mellitus(T2DM) combinated with or without hypertension using left atrial volume tracking method(LAVT). Methods Thirty-one simple T2DM(T2DMI group) ,21 T2DM accompany with hypertension(T2DM2 group) and forty-five healthy subjects (control group) were enrolled in this study. Ultrasound LAVT(EUB-6500, Hitachi Medical Corporation) was applied to display and analyzed the LA volume loop imaging on the standard LV apical two and four chamber views. The maximal and the minimal LA volume (LAVmax, LAVmin) and the volume before LA contraction (LAVp) were recorded from the LA volume loop. The body surface area was used to correct these volume indexs. The LA reservoir function was assessed by calculating the total of LA filling volume (LAVItotal) and the expansion index(iLAVIe). The passive and active emptying percentage of the total emptying volume(LAVIpass, LAVIact) and the emptying index(iLAVIpass,iLAVIact) were caculated as the parameters of the LA conduit and booster pump function. Results Compared with the values in the control group, the LAVhotal,LAVIact were significantly higher and the LAVlpass,iLAVlpass were lower in the T2DM group (all P<0.05) ,while the iLAVIact was higher only seen in the T2DM2 group(P<0. 05). The LAVlact, iLAVIact were higher and the LAVIpass was lower in T2DM2 group than those in the T2DM1 group (all P<0.05). Conclusions The LA conduit hypofunction in primary in the prophase T2DM,when combinated with hypertension the LA constriction function compensatorily increased, LAVT can evaluate the function of LA in patients with T2DM accurately and rapidly.