Experimental Study of Assessment on Ventricular Activation Origin and Contraction Sequence by Doppler Tissue Imaging

To evaluate the possibility and accuracy of Doppler tissue image (DTI) on assessment of normal and abnormal ventricular activation and contraction sequence, 9 open chest canine hearts were analyzed by acceleration mode, M mode, and spectrum mode DTI. Our results showed that: (1) Acceleration mode DTI could show the origin of activation and conduction sequence on line; (2) M mode DTI revealed that the activation in mid interventricular septum was earlier than that in mid left ventricular posterior wall at sinus activation; (3) Spectrum DTI showed the ventricular endocardium was activated earlier than the ventricular epicardium in all segments at sinus rhythm. The earliest site of activation of the normal ventricular wall was at middle interventricular septum; the latest site was at basal posterior wall; the contraction sequence was different at the different walls; (4) During abnormal ventricular activation, mid left ventricular posterior wall was activated earliest in accordance with the pacing sites. Abnormal ventricular activation was slower than sinus activation, and the contraction sequence varied at different sites of ventricular wall. It is concluded that DTI can be used to localize the origin of normal or abnormal myocardial activation and to assess the contraction sequence conveniently, accurately and non invasively.

Evaluation of Normal Fetal Left Cardiac Function by Tissue Doppler Imaging

To explore the feasibility of using tissue Doppler imaging technique for the evaluation of fetus＇s left ventrieular diastolic function, and to confirm its reliability by comparing it with traditional methods, this study examined 61 pregnant women in whom satisfactory images were obtained of fetal eehoeardiography. The peak velocity of blood stream were measured, including E, A and E/A at mitral valve orifice on the four chamber view with pulse wave. And then tissue Doppler imaging mode was employed to measure the velocity of mitral valve annulus including Ea, Aa, Sa and Ea / Aa. Correlation analysis was conducted between the velocity of orifice and that of annulus in terms of gestation age. And then correlation analysis was performed between above data and gestation ages. A positive correlation was found between the velocity of orifice and that of annulus, and the velocity increased with the gestation age. The change was the most significant between the 28th and the 34th week of gestation age. Our study showed that it is feasible to evaluate the fetus＇s left ven trieular diastole function by tissue Doppler imaging. Its stability can avoid the influence of fetal heart rates and preload.

Value of Low Dose Dobutamine Doppler Tissue Imaging for Detecting Hibernating Myocardium

Summary: In order to assess the value of Doppler tissue imaging (DTI) in detecting viable hibernating myocardium, 20 patients with coronary artery disease and chronic left ventricular dysfunction underwent low dose dobutamine stress echocardiography and low dose dobutamine stress DTI. The results showed that among the 100 asynergic segments, 35 segments showed improvement after dobutamine infusion (group H) and no changes were observed in the remaining 65 segments (group N). The left ventricular echocardiographic score index decreased from 1.60±0. 35 to 1.44±0.36 ( n =20, P <0.01). During low dose dobutamine stress DTI, there was no difference in the values of velosity of S wave (V s) before dobutamine infusion between two groups. However, after dobutamine infusion, the values of V s and VR in group H were significantly higher than those in group N (V s:10.1±3.0 cm/s vs 7.3±2.2 cm/s, P <0.01; VR: 60 %±41 % vs 25 %±32 %, P <0.001). 95.7 % asynergic myocardial segments with VR≤0 had no viability while 86 % asynergic segments with VR>80 % were viable myocardium. It is concluded that the different reactions to dobutamine stress between hibernating and necrosis myocardium could be showed by DTI and it is more clinically significant when VR≤0 and VR>80 %.

Doppler Tissue Imaging Assessment of Left Ventricular Systolic Dyssynchrony in Severe Heart Failure Patients With a Normal QRS Duration

Objectives To assess the prevalence of systolic dyssynchrony of the left ventricular （LV） walls in patients of heart failure（HF） with a normal QRS duration by Doppler tissue imaging （DTI）. Methods 20 patients of HF with a normal QRS duration and 20 healthy individuals were investigated with DTI to quantitatively analyze their pulsed-wave Doppler spectrum of basal and middle segments in six walls of left ventricle. The time between the onset of the QRS complex of the surface ECG and the onset of the systolic wave of pulsed-wave Doppler spectrum was measured （TS）. LV systolic synchronization was assessed by the maximal difference （MD） in time of TS, the standard deviation （SD） and the coefficient of variation （CV） of TS in the all 12 LV segments. Results When a TS-MD of TS〉 53.08 ms, a TS-SD of TS 〉18.08 ms and a TS-CV of TS 〉 0.91 （＋1.65 SD of normal controls） was used to define significant systolic dyssynchrony, the prevalence of systolic dyssynchrony was 55.0 %, 55.0 % and 55.0 %, respectively, in the HF patients group, significantly higher than those in the normal control and the locations of delayed contraction of these patients were different. Conclusions LV systolic dyssynchrony could be commonly demonstrated by DTI in HF patients with a normal QRS duration. This finding will support the view about the possibility that more HF patients could benefit from cardiac resynchronization therapy.

Pulsed Doppler Tissue Imaging for Assessment of Left Ventricular Systolic and Diastolic Synchronicity in Normal Subjects

Objectives To quantitatively analyze the longitudinal myocardial systolic and diastolic velocities and time intervals of the left ventricle in normal subjects, and to explore the value of pulsed Doppler tissue imaging （DTI） for the assessment of left ventricular systolic and diastolic synchronicity. Methods Twenty and six healthy subjects were studied by pulsed DTI. The septal and lateral, anterior and inferior walls of the left ventricle were displayed respectively, and basal and middle segments of each wall were selected for myocardial motion spectrum sampling. DTI parameters were： peak systolic myocardial velocity （s）, regional pre-ejection period （PEP）, time to the peak of s wave （Ts）, regional ejection time （ET） ; peak early diastolic velocity （e）, peak late diastolic velocity （a）, e/a ratio, time to the beginning of e wave （QE）, time to the peak of e wave （Te） and regional isovolumic relaxation time （IVRT）. Results The e and e/a were significantly different among basal segments, and s and e/a were significantly different among middle segments, with the highest value in lateral segments and the lowest value in septal segments. The s, e and a were all significantly higher in basal segments than middle segments. None of the systolic time intervals （PEP, Ts and ET） and diastolic time intervals （QE, Te and IVRT） were significantly different among basal segments and middle segments, neither were they when basal segment was compared with middle segment. Conclusions In normal subjects, the longitudinal myocardial systolic and diastolic velocities of the left ventricle are not homogeneous, but the contraction and relaxation are highly synchronized. Pulsed DTI can be used to quantitatively analyze the systolic and diastolic synchronicity of the heart.

In Vitro Validation of Tissue Doppler Left Ventricular Regional Wall Velocities by Using a Novel Balloon Phantom

To investigate the validity and accuracy of tissue Doppler imaging (TDI) using a novel balloon phantom, validation of TDI myocardial velocity measurements has been carried out indirectly from conventional M mode images. However it is not a true and independent gold standard. We described a new TDI validation method by using a specially developed left ventricular balloon model mounted in a water bath and constructed using two pear shaped balloons. It was connected to a pulsatile flow pump at 8 stroke volumes (50-85 ml/beat). The displacement and velocity of the balloon walls were recorded simultaneously by video imaging and TDI on a GE Vingmed System Five with a 5 MHz phased array probe at the highest frame rates available. Conventional M mode and 2 D imaging verified that our balloon model mimicked the shape and wall motion of left ventricle. There was a good correlation and agreement between the maximum video excursion of the anterior and posterior walls of the phantom and the results of the temporal integration of digital distance data by TDI (Anterior wall: r =0.97, SEE=0.24 mm, ±s =0.04±0.24 mm; Posterior wall: r =0.95, SEE=0.22 mm, ±s =0.03±0.24 mm). Analysis of the velocity profile by the TDI method showed that the velocity at each measured point was correlated well with the velocity obtained from the video images (Anterior wall: r =0.97, SEE=0.30 mm, ±s =-0.04±0.28 mm; Posterior wall: r =0.97, SEE=0.30 mm, ±s =0.04±0.28 mm). Our balloon model provided a new independent method for the validation of TDI data. This study demonstrated that the present TDI system is reliable for measuring wall motion distance and velocity.

Tissue Doppler Study before and after PCI in Patients with Chronic Stable Angina and Apparent Normal Ventricular Function for Evaluation of Myocardial Function

Background: This study aimed to determine the impact of the percutaneous coronary intervention (PCI) on myocardial function assessed by tissue Doppler echocardiography. Methods: Conventional two-dimensional echocardiography and Myocardial tissue peak velocities were recorded at the lateral, ant.septal, post.septal, posterior, ant. and inferior angles of the mitral annulus as well as at the lateral tricuspid annulus by pulsed-wave tissue Doppler echocardiography before PCI, as well as 1 day and 6 weeks after intervention. Results: Fifty consecutive patients with chronic stable angina and preserved systolic left ventricular function (mean age, 58.3 ± 6.594 years;32 men) undergoing PCI were studied. Conventional echocardiographic revealed no statistically significant difference between pre- and post-PCI (1 day after PCI and 6 weeks after PCI) as regarding trans-mitral and trans-tricuspid flow velocities except as regarding LVEDD, LVESD and LVEF which showed a significant improvement post-PCI. Compared with pre-interventional values, systolic peak velocity and early diastolic velocities improved at all sites (P ≤ 0.05 for each). The most pronounced improvement occurred in the septal area. Similarly, late diastolic velocities improved at all sites (P ≤ 0.05 for each) except at post Wall A’. Also, there was a significant improvement of E’DT & E’/A’ ratio after PCI (P value is significant <0.05 for each) but there was insignificant difference between pre & post PCI for E/E’ (P-value = 0.154). There was a significant improvement in tissue Doppler measures of early, late diastolic function and E’/A’ at the lateral tricuspid annulus after PCI compared with baseline values (P value is significant <0.05) but there was an insignificant change in tissue Doppler measures at the lateral tricuspid annulus of E’DT & E/E’ after PCI (repeated measures ANOVA P-value is >0.05 for each). There were significant reductions in IVRT, IVCT & MPI after PCI (P value is significant <0.05 for each) but there was insignificant change in ET after PCI (P-value = 0.09) at the septal angle of the mitral annulus and the lateral angle of the tricuspid annulus. Conclusions: Tissue Doppler parameters of diastolic and systolic function improve early after successful PCI, and this effect persists to 6 weeks after the intervention that emphasizes its value in the improvement of regional and global LV functions and myocardial contractility.

Tissue Doppler imaging study of right ventricular myocardial systolic activation in subjects with pulmonary arterial hypertension

Background Tissue Doppler imaging （TDI） has provided an objective means to quantify global and regional left ventricular （LV） and right ventricular （RV） function with improved accuracy and greater reproducibility than conventional echocardiography. This study was conducted to assess RV myocardial systolic activation by TDI in subjects with pulmonary arterial hypertension （PAH）. Methods A total of 30 patients with PAH and 30 healthy volunteers, all comparable in age and sex, underwent standard Doppler echo and TDI. Using pulsed Doppler echocardiography combined with TDI, the following regional parameters were evaluated in three different myocardial segments （RV basal lateral wall, basal septal, and LV basal lateral） on apical 4-chamber view： systolic （Sm）, early- and late-diastolic （Em and Am） peak velocities. RV myocardial systolic activation delay was defined as the difference in time to peak TDI systolic velocities between the RV basal lateral wall and basal septal. In addition, RV end-diastolic and end-systolic areas were measured to calculate RV fractional area change from the same apical 4-chamber view. Results Compared with the control group, patients with PAH showed increased RA and RV end-diastolic diameter （RA： （4.5±1.2）cm vs （3.0±0.8）cm, P〈0.05 and RV： （4.8±1.9）cm vs （3.4±0.5）cm, P〈0.05） and reduced RV fractional area change; （35±14）% vs （56±9）%, P〈0.05. These PAH patients showed lower myocardial peak velocities and a significant activation delay compared with controls （P〈0.05）. Moreover, a strong correlation between RV myocardial systolic activation delay and RV fractional area change was shown in patients with pulmonary arterial hypertension （r = -0.82）. Conclusions In PAH, RV myocardial systolic activation was markedly delayed, which was directly related to the RV fractional area change. RV myocardial systolic activation delay assessed by TDI could offer a unique approach to predict RV dysfunction.

Effect of Shenmai Injection(参麦注射液)on Ventricular Diastolic Function in Patients with Chronic Heart Failure:An Assessment by Tissue Doppler Imaging

Objective：To assess the effect of Shenmai Injection（参麦注射液,SMI） on left ventricular diastolic function（LVDF） in patients with chronic heart failure（CHF） by tissue Doppler imaging（TDI）.Methods：Sixty-four CHF patients were randomly assigned to two groups,the observation group and the control group.Basic treatment including polarized liquid therapy was given to all the patients.In addition,SMI was given to patients of the observation group.The treatment duration was 14 days.TDI was performed in all the patients 3 days prior to the initiation of the treatment and one week after the medication to measure the average movement velocity of the mitral ring of the left ventricle at the early systolic stage and late diastolic stage（Ea and Aa）;the outcomes were compared with the corresponding parameters obtained from blood flow Doppler echocardiography, namely,the velocity of the E-wave（E） and A-wave（A）.Results：After treatment,Ea and Ea/Aa increased and Aa decreased significantly in the observation group（P〈0.05）.In the control group,although some improvement was seen,there was no statistically significant change（P〉0.05）.No statistical significance was shown between groups in these parameters after treatment.Conclusion：TDI assessment shows that SMI could effectively improve the LVDF in CHF patients.

Early Changes in Atrial Electromechanical Coupling in Patients with Hypertension： Assessment by Tissue Doppler Imaging

Background： Hypertension （HT） is associated with atrial electrophysiological abnormalities. Echocardiographic pulsed wave tissue Doppler imaging （TDI） is one of the noninvasive methods for evaluation of atrial electromechanical properties. The aims of our study were to investigate the early changes in atrial electromechanical conduction in patients with HT and to assess the parameters that affect atrial electromechanical conduction. Methods： Seventy-six patients with HT （41 males, mean age 52.6 i 9.0 years） and 41 controls （22 males, mean age 49.8 ± 7.9 years） were included in the study. Atrial electromechanical coupling at the right （PRA）, left （PLA）, interatrial septum （PIS） were measured with TDI. Intra- （right： PIS-PRA, left： PLA-PIS） and inter-atrial （PLA-PRA） electromechanical delays were calculated. Maximum P-wave duration （Pmax） was calculated from 12-lead electrocardiogram. Results： Atrial electromechanical coupling at PLA （76.6 ± 14.1 ms vs. 82.9 ±15.8 ms, P - 0.036）, left intra-atrial （10.9 ±5.0 ms vs. 14.0 ± 9.7 ms, P = 0.023）, right intra-atrial （10.6 ± 7.8 ms vs. 14.5 ± 10.1 ms, P= 0.035）, and interatrial electromechanical （21.4± 9.8 ms vs. 28.3 ± 12.7 ms, P = 0.003） delays were significantly longer in patients with HT. The linear regression analysis showed that left ventricular （LV） mass index and Pmax were significantly associated with PLA （P = 0.001 and P = 0.002, respectively）, and the LV mass index was the only related factor for interatrial delay （1~ = 0.001）. Conclusions： Intra- and interatrial electromechanical delay, PLA were significantly prolonged in hypertensive patients. LV mass index and Pmax were significantly associated with PLA, and the LV mass index was the only related factor for interatrial delay. The atrial TDI can be a valuable method to assess the early changes of atrial electromechanical conduction properties in those patients.

Cardiac function evaluated by Tei index of tissue doppler imaging and brain natriuretic peptide in patients with acute coronary syndrome and hyperglycemia

Background Recent studies demonstrated that N-terminal pro-brain natriuretic peptide（NT-pro BNP） increases in patients with diabetes mellitus and raised concerns about the diagnostic validity of NT-pro BNP in assessment of cardiac function in patients with hyperglycemia.Current investigation was carried out to observe the influence of hyperglycemia on the correlation of NT-pro BNP and cardiac function index in patients with acute coronary syndrome（ACS）.Methods Fifty patients with ACS were enrolled and divided into hyperglycemia group（fasting plasma glucose（FPG） ≥ 6.1 mmol/L） and euglycemia group（FPG 〈 6.1 mmol/L）.All the patients underwent routine transthoracic ecocardiagraphy and tissue Doppler imaging（TDI） investigation.Blood sample were obtained with 24 hours of hospitalization for measuring of NT-proBNP level.Relation between TDI-Tei index and the level of NT-proBNP were analyzed in the two groups respectively.Result TDI-Tei index,systolic index and diastolic index were all significantly higher in hyperglycemia group than that in euglycemia group（0.679 ± 0.139 vs 0.600 ± 0.093,P = 0.022;0.294 ± 0.074 vs 0.258 ± 0.035,P = 0.036;0.385 ± 0.069 vs 0.342 ± 0.068,P = 0.032）.TDI-Tei index was significantly negatively correlated with the level of log NT-pro BNP in both hyperglycemia group and euglycemia group（rp = 0.673,P = 0.000;rp = 0.354,P = 0.000）.Conclusions（1）Cardiac function in patients with ACS complicated with hyperglycemia is inferior to that in patients with euglycemia;（2）Assessment of cardiac function with NT-proBNP is reliable in patients with hyperglycemia.

Assessment of left ventricular segmental function after autologous bone marrow stem cells transplantation in patients with acute myocardial infarction by tissue tracking and strain imaging

Background Emerging evidence suggests that stem cells can be used to improvecardiac function in patients after acute myocardial infarction. In this randomized trial, we aimedto use Doppler tissue tracking and strain imaging to assess left ventricular segmental functionafter intracoronary transfer of autologous bone-marrow stem cells ( BMCs) for 6 months' follow up.Methods Twenty patients with acute myocardial infarction and anterior descending coronary arteryocclusion proven by angiography were double-blindedly randomized into intracoronary injection ofbone-marrow cell (treated, n = 9 ) or diluted serum ( control, n = 11) groups. GE vivid 7 andQ-analyze software were used to perform echocardiogram in both groups 1 week, 3 months and 6 monthsafter treatment. Three apical views of tissue Doppler imaging were acquired to measure peak systolicdisplacement ( D_s) and peak systolic strain (ε_(peak)) from 12 segments of LV walls. Leftventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume ( ESV) wereobtained by Simposon's biplane method. Results (1) 3 months later, D_a and ε_(peak) over theinfract-related region clearly increased in the BMCs group [D_8: (4.49 ±2.71) mm vs (7.56 ±2.95)mm, P < 0. 01; ε_(peak): ( - 13.40 ±6.00)% vs ( - 17.06 ± 6.05)% , P<0.01] , but not in thecontrol group [ D_8: (4.74 ±2.67) mm vs (5.01 ±3.23) mm, P >0.05; ε_(peak): ( - 13.84 ± 6.05) %vs ( - 15.04 ± 6.75) % , P > 0.05 ]. At the same time, D_s over the normal region also increased,but the D_8 enhancement was markedly higher in the BMCs group than that in the control group [ (3.21±3.17) mm vs (0.76 ± 1.94) mm, P <0.01 ]. Parameters remained steady from the 3rd to 6th month ineither group (P >0.05). (2) LVEF in treated and control groups were almost the same at baseline (1st week after PCI) [ (53.37 ± 8.92) % vs (53.51 ± 5.84) % , P > 0.05 ]. But 6 months later, LVEFin the BMCs group were clearly higher than that in the control group [(59.33 ± 12.91)% vs (50.30 ±8.30)%, P < 0.05 ]. (3) There were no evident difference in EDV or ESV between two groups atbaseline [ EDV; (113.74 ±23.24) ml vs (129.94 ±32.72) ml , P>0.05; ESV: (57.12 ±18.66) ml vs(62.09 ± 17.68) ml, P > 0.05 ]. Three months later, EDV and ESV in the control group were markedlygreater than those in the BMCs group [EDV; (154.89 ±46.34) ml vs (104.85 ±33.21) ml, P<0.05; ESV:(82.91 ±35.79) ml vs (49.54 ± 23.32) ml, P < 0.05 ]. But EDV and ESV did not change much from 3rdto 6th month in either group (P>0.05). Conclusions Emergency transplantation of autologous BMCs inpatients with acute myocardial infarction helps to improve global and regional contractility andattenuate post-infarction left ventricular remodeling. Tissue tracking and strain imaging providequick, simple and noninvasive methods for quantifying left ventricular segmental function in humans.

Assessment of cardiac function and synchronicity in subjects with isolated bundle branch block using Doppler imaging

Background Using tissue Doppler imaging and conventional echocardiographic technique, we examined the cardiac function and synchronicity in individuals with isolated right bundle branch block （RBBB） or left bundle branch block （LBBB） and assessed the relationship between QRS duration and synchronicity.

Assessment of atrial electromechanical interval using echocardiography after catheter ablation in patients with persistent atrial fibrillation

We sought to investigate variation of atrial electromechanical interval after catheter ablation procedure in patients with persistent atrial fibrillation using pulse Doppler（PW） and pulse tissue Doppler imaging（PW-TDI）.A total of 25 consecutive in-patients with persistent atrial fibrillation,who restored sinus rhythm after ablation procedure,were recruited in our cardiac center.Echocardiography was performed on each patient at 2 hours,1 day,5 days,1 month and 3 months after the ablation therapy,and atrial electromechanical delay was measured simultaneously by PW and PW-TDI.There was no significant difference between PW and TDI in measuring atrial electromechanical delay.However,at postoperative 2 hours,peak A detection rates were mathematically but nonsignificantly greater by PWTDI than by PW.Second,there was a significant decreasing trend in atrial electromechanical interval from postoperative 2 hours to 3 months,but only postoperative 2-hour atrial electromechanical interval was significantly greater than atrial electromechanical interval at other time.Lastly,patients without postoperative 2-hour atrial electromechanical interval had a significantly longer duration of atrial fibrillation as compared to those with postoperative 2-hour atrial electromechanical interval,by the PW or by PW-TDI,respectively.In patients with persistent atrial fibrillation,atrial electromechanical interval may decrease significantly within the first 24 hours after ablation but remain consistent later,and was significantly related to patients＇ duration of atrial fibrillation.Atrial electromechanical interval,as a potential predicted factor,is recommended to be measured by either PW or TDI after24 hours,when patients had recovered sinus rhythm by radiofrequency ablation.

Quantification analysis of pleural line movement for the diagnosis of pneumothorax

BACKGROUND There is no research on quantitative pleural line movement.In this study,we assume that tissue Doppler and its quantitative technology can quantify the pleural line movement and can be used to diagnose pneumothorax.AIM To evaluate the quantitative assessment of pleural line movement measured by tissue Doppler imaging(TDI)for pneumothorax diagnosis.METHODS Adult patients(n=45)diagnosed with unilateral pneumothorax were included in this study.Each patient underwent TDI of both lungs.The pneumothorax side and contralateral normal lung side were compared using several indices obtained from TDI:peak pleural line velocity(PV_(max)),peak chest wall tissue velocity(CV_(max)),peak pleural line strain value(PS_(max)),peak chest wall tissue strain value(CSmax),PV_(max)/CV_(max)and PS_(max)/CSmax.The receiver operating characteristic analysis was used to evaluate the performance of these quantitative assessments for pneumothorax diagnosis.RESULTS Various quantitative variables of the pneumothorax side were all lower than that of the non-pneumothorax side and included the PV_(max)(0.36 cm/s vs 0.59 cm/s,P<0.001),PS_(max)(1.14%vs 1.90%,P=0.001),PV_(max)/CV_(max)(1.06 vs 4.93,P<0.001),and PS_(max)/CSmax(0.76 vs 1.74,P<0.001).For the discrimination of pneumothorax,the cut-off values of the PV_(max),PS_(max),PV_(max)/CV_(max),and PS_(max)/CSmax were calculated as 0.50 cm/s,0.94%,1.96,and 1.12,respectively.Similarly,the sensitivities and specificities of PV_(max),PS_(max),PV_(max)/CV_(max),and PS_(max)/CSmax were 96%and 62%,47%and 91%,93%and 96%,and 82%and 93%,respectively.The area under the receiver operating characteristic curve were 0.84,0.72,0.99,and 0.91,respectively,for PV_(max),PS_(max),PV_(max)/CV_(max),and PS_(max)/CSmax.CONCLUSION Quantification analysis of pleural line movement using TDI is a useful tool for the diagnosis of pneumothorax.

Optimized cardiac resynchronization therapy in patients with congestive heart failure

Heart failure was a major and increasing public health problem, with an almost ＂epidemic＂ increase in the number of patients. Despite recent advances in pharmacotherapy, the prognosis remains poor. Cardiac resynchronization therapy （CRT）, by pacing right and left ventricles, has been proved to improve symptoms and reduce mortality for heart failure patients with cardiac dyssynchrony, However, 20% to 30% of patients did not respond to CRT. The good cardiac synchronicity before CRT and the remaining atrioventficular, inter- and intra-ventricular dyssynchrony after CRT may explain the non-response. New echocardiographic techniques, and in particular tissue Doppler imaging （TDI） analysis, has been proved to be a helpful tool in evaluating cardiac dyssynchrony, as well as in assessing the degree of cardiac resynchronization after biventricular device implantation. So, in this study, we optimized the pacing parameters to determine whether echo-guided optimizing of AV/VV delays would enhance the effect of CRT on cardiac function and synchronicity.

Evaluation of cardiac function in patients with arrhythmogenic right ventricular cardiomyopathy by echocardiography

Background Arrhythmogenic right ventricular cardiomyopathy （ARVC） mainly performs local myocardial abnormal movements and tissue Doppler and spot tracking technique can accurately reflect myocardial movement. However, the technique is still rarely used in research of ARVC. Methods The study enrolled 28 ARVC patients and 28 normal controls. Right ventricular parameters were measured by two-dimensional echocardiography, tissue Doppler imaging, speckle tracking imaging in order to compare the difference between two groups. Results Morphological indices （right ventricular inflow tract inner diameter and right ventricular outflow tract inner diameter） and functional indices （right ventricular peak S＇, right ventricular E＇/ A＇ ratio, tricuspid annular plane systolic excursion, right ventricular fractional area change and right ventricular inferior and lateral wall longitudinal strain） showed significant difference between the ARVC group and control group. All the above-mentioned indices were analyzed by receiver operating characteristic curve （ROC curves）. Area under the curve （AUC） of right ventricular inferior wall longitudinal strain was the largest one （AUC = 0.94） with an optimal cutoff value of -19.5%. Conclusion Compared with two- dimensional echocardiography and tissue Doppler imaging, right ventricular inferior wall longitudinal strain is a more sensitive predictor for changes of ARVC.