Assessment of Intraventricular Mechanical Dyssynchrony and Prediction of Response to Cardiac Resynchronization Therapy: Comparison between Tissue Doppler Imaging and Real-Time Three-Dimensional Echocardiography

Evaluating the predictive efficacy of real-time 3D echocardiography in cardiac resynchronization therapy

BACKGROUND

The aim of this study is to assess the predictive efficacy of real-time three-dimensional echocardiography (RT-3DE) and QRS wave duration in determining the response to cardiac resynchronization therapy (CRT) and assessing left ventricular systolic function pre- and post-CRT device implantation.

METHOD

A total of 51 patients with heart failure undergoing CRT at the Second Affiliated Hospital of Nantong University between January 1, 2013, and October 31, 2020, were enrolled in this study. Traditional two-dimensional echocardiography and RT-3DE were performed pre and post-CRT, with QRS wave width data from electrocardiograms and additional clinical information collected. Patients were categorized into CRT responder (n = 36) and CRT non-responder (n = 15) groups based on their response to CRT device implantation. Comparative analyses were conducted on the general characteristics of both groups, as well as the predictive efficacy of RT-3DE and QRS wave width for CRT responsiveness and left ventricular systolic function. Data on the standard deviation (Tmsv16-SD, Tmsv12-SD, Tmsv6-SD) and maximum difference (Tmsv16-Dif, Tmsv12-Dif, Tmsv6-Dif) of left ventricular end-systolic volume (LVESV) at segments 16, 12, and 6, as well as QRS wave width, were collected and analyzed.

RESULTS

The indicators Tmsv6-Dif, Tmsv12-Dif, Tmsv16-Dif, Tmsv6-SD, Tmsv12-SD, Tmsv16-SD, and QRS wave width exhibited significantly higher values in the CRT responder group when compared to the CRT non-responder group (P < 0.05). Among these, Tmsv16-SD demonstrated superior predictive performance for post-CRT response, with a sensitivity of 88.9%, specificity of 80.0%, and a diagnostic cut-off value of 6.19%. This predictive capability exceeded that of the conventional indicator, QRS wave width.

CONCLUSION

RT-3DE enables accurate prediction of post-CRT patient response and significantly facilitates quantitative assessment of CRT therapy efficacy.

Real-time three-dimensional echocardiography for detection of cardiac sarcoidosis in the early stage: a cross-sectional single-centre study

BACKGROUND

Sarcoidosis with cardiac involvement has a relatively high morbidity and mortality, and early diagnose of cardiac sarcoidosis is a critical issue. Systolic dyssynchrony index (SDI) measured by three-dimensional echocardiography was used in our study for detection of subclinical left ventricular (LV) systolic dysfunction in patients with sarcoidosis and normal LV function on two-dimensional echocardiography.

METHODS

Forty-four patients diagnosed with sarcoidosis (without clinically apparent cardiac involvement) and 44 healthy control subjects were included in this study. Two-dimensional echocardiographic parameters, also LV volumes and SDI measured by 3D echocardiography were analyzed in all participants.

RESULTS

While two-dimensional echocardiographic results of both study groups were similar; SDI_16 (SDI for 16 segments of LV) results were significantly higher in sarcoidosis group compared to healthy controls (6.99 ±5.02 vs 2.89 ± 1.32, p < 0.0001).

CONCLUSION

SDI_16 was higher in patients with sarcoidosis compared to healthy controls probably due to patchy infiltration characteristic of the disease. This parameter could be used as a marker to identify patients with cardiac involvement of sarcoidosis in the early phase.

Prognostic value of real-time three-dimensional echocardiography compared to two-dimensional echocardiography in patients with systolic heart failure

Heart failure (HF) is associated with morbidity and mortality. Real-time three-dimensional echocardiography (RT3DE) may offer additional prognostic data in patients with HF. The study aimed to evaluate the prognostic value of real-time three-dimensional echocardiography (RT3DE). This is a prospective study that included 89 patients with HF and left ventricular ejection fraction (LVEF) < 0.50 who were followed for 48 months. Left atrium and ventricular volumes and functions were evaluated by RT3DE. TDI and two-dimensional echocardiography parameters were also obtained. The endpoint was a composite of death, heart transplantation and hospitalization for acute decompensated HF. The mean age was 55 ± 11 years, and the LVEF was 0.32 ± 0.10. The composite endpoint occurred in 49 patients (18 deaths, 30 hospitalizations, one heart transplant). Patients with outcomes had greater left atrial volume (40 ± 16 vs. 32 ± 12 mL/m²; p < 0.01) and right ventricle diameter (41 ± 9 vs. 37 ± 8 mm, p = 0.01), worse total emptying fraction of the left atrium (36 ± 13% vs. 41 ± 11%; p = 0.03), LVEF (0.30 ± 0.09 vs. 0.34 ± 0.11; p = 0.02), right ventricle fractional area change (34.8 ± 12.1% vs. 39.2 ± 11.3%; p = 0.04), and greater E/e' ratio (19 ± 9 vs. 16 ± 8; p = 0.04) and systolic pulmonary artery pressure (SPAP) (50 ± 15 vs. 36 ± 11 mmHg; p < 0.01). In multivariate analysis, LVEF (OR 4.6; CI 95% 1.2-17.6; p < 0.01) and SPAP (OR 12.5; CI 95% 1.8-86.9; p < 0.01) were independent predictors of patient outcomes. LVEF and the SPAP were independent predictors of outcomes in patients with HF.

Phase analysis of gated myocardial perfusion single-photon emission computed tomography after coronary artery bypass graft surgery: reflection of late reverse remodeling in patients with patent grafts after coronary artery bypass graft surgery

OBJECTIVE

Phase analysis using gated myocardial perfusion single-photon emission computed tomography (GMPS) is a tool used to assess left ventricular (LV) dyssynchrony. We attempted to investigate the role of LV dyssynchrony assessed by GMPS using phase analysis for the late LV function after coronary artery bypass graft surgery (CABG) in patients with patent grafts.

METHODS

A total of 45 patients who received off-pump CABG with patent graft 1 year after CABG and preserved perfusion reserve were enrolled retrospectively. All patients underwent GMPS before and 3 months and 1 year after CABG. Using the Emory Cardiac Toolbox, both phase histogram bandwidth (PBW) and phase SD derived by phase analysis were used for the analysis, in addition to the conventional perfusion parameters. For the evaluation of LV function, transthoracic echocardiography was also performed.

RESULTS

All of the patients showed perfusion improvement (paired t-test, P<0.05) after CABG. Nonetheless, 30 of 45 patients showed LV dyssynchrony 3 months after CABG. One year after CABG, however, 25 out of 45 patients showed reverse remodeling. Among those patients with reverse remodeling, 19 patients had shown LV 3 months after CABG. Using stepwise logistic regression with forward selection, PBW 3 months after CABG could predict reverse remodeling 1 year after CABG (odds ratio 1.03, P<0.05). Using receiver operating characteristic analysis, PBW 3 months after CABG had the largest area under the curve to detect reverse remodeling 1 year after CABG with a cut-off value of 82 (sensitivity 0.95, specificity 0.56, P<0.001).

CONCLUSION

Postoperative LV dyssynchrony assessed by GMPS using phase analysis may reflect late reverse remodeling and potential of further functional improvement in patients with patent grafts and preserved perfusion reserve after CABG.

Left Ventricular Dyssynchrony by Three-Dimensional Echocardiography: Current Understanding and Potential Future Clinical Applications

Left ventricular mechanical dyssynchrony is an important prognostic factor for patients with symptomatic systolic heart failure and has emerged as a therapeutic target for cardiac resynchronization therapy (CRT). However, approximately one-third of patients fail to improve after CRT based on current guideline recommendations and electrocardiographic criteria. Two-dimensional echocardiography and tissue Doppler-based techniques have shown variable results in assessment of left ventricular (LV) dyssynchrony and have limited value in clinical practice. Three-dimensional echocardiography (3DE) is an appealing novel imaging modality that has been recently used in quantitative evaluation of global and regional LV function. There is accumulating evidence that 3DE measurement of LV systolic dyssynchrony index may potentially play a role in predicting the short- and long-term response to CRT and further improve patient selection for CRT. New developments in 3DE speckle tracking technique and strain analysis may further improve the accuracy of LV mechanical dyssynchrony assessment in this population. In addition, recent studies suggest that mechanical dyssynchrony is present in patients with LV hypertrophy and diastolic heart failure. Three-dimensional echocardiographic assessment of dyssynchrony may aid in diagnosis and in predicting long-term outcome in these patients. We will summarize current understanding of 3DE techniques and parameters in assessment of LV mechanical dyssynchrony in the population of patients with systolic heart failure, LV hypertrophy, and diastolic heart failure. A number of the novel 3DE techniques described in this review are early in their stage of development, and they will continue to evolve and need further testing in large multicenter studies.

Prevalence of Left Ventricular Dyssynchrony in Patients with Congenital Atrioventricular Block and Long-Term Pacing: A Three-Dimensional Echocardiographic Study

BACKGROUND

Left ventricular (LV) dysfunction is the major reason for poor outcomes in patients with congenital complete atrioventricular block (CCAVB) and pacemaker. Long-term pacing has been associated with LV mechanical dyssynchrony. However, the relationship of dyssynchrony and LV dysfunction is not clear.

OBJECTIVE

We sought to evaluate the prevalence of LV dyssynchrony by real time three-dimensional echocardiography (RT3DE) in patients with CCAVB and its association with LV dysfunction. In addition, we evaluated the agreement between RT3DE and tissue Doppler imaging (TDI) for detecting LV dyssynchrony.

METHOD

We studied 50 patients [median age 20 years old (5 months to 62 years), 68% women] with CCAVB and pacemaker who underwent complete two-dimensional echocardiography and RT3DE. LV dyssynchrony was considered if the systolic dyssynchrony index (SDI) was ≥ 5%. Intraventricular mechanical delay was defined by TDI when differences in electromechanical activation between LV walls were > 65 msec.

RESULTS

LV systolic dysfunction was present in 16 patients (32%) by two-dimensional and in 20 patients (40%) by RT3DE. There was a good correlation between LV ejection fraction by two-dimensional and RT3DE (r = 0.75; P < 0.001). Fourteen (28%) patients had intraventricular dyssynchrony by TDI, while 12 (24%) had intraventricular dyssynchrony by RT3DE. There was a good agreement between LV dyssynchrony by TDI and RT3DE (Kappa = 0.735; P < 0.001). There was a negative correlation between LV ejection fraction and SDI obtained by RT3DE (r = -0.58; P < 0.001) CONCLUSIONS: In patients with CCAVB and long-term pacing, LV dyssynchrony occurred in one-third of patients and was related to LV dysfunction. There was a good correlation between dyssynchrony obtained by RT3DE and TDI.

Assessment of LV ejection fraction using real-time 3D echocardiography in daily practice: direct comparison of the volumetric and speckle tracking methodologies to CMR

AIMS

This study is the first to directly compare two widely used real-time 3D echocardiography (RT3DE) methods of cardiac magnetic resonance imaging (CMR) and assess their reproducibility in experienced and less experienced observers.

METHODS

Consecutive patients planned for CMR underwent RT3DE within 8 h of CMR with Philips (volumetric method) and Toshiba Artida (speckle tracking method). Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were measured using RT3DE, by four trained observers, and compared with CMR values.

RESULTS

Thirty-five patients were included (49.7 ± 15.7 years; 55 % male), 30 (85.7 %) volumetric and 27 (77.1 %) speckle tracking datasets could be analysed. CMR derived LVEDV, LVESV and LVEF were 198 ± 58 ml, 106 ± 53 ml and 49 ± 15 %, respectively. LVEF derived from speckle tracking was accurate and reproducible in all observers (all intra-class correlation coefficients (ICC) > 0.86). LVEF derived from the volumetric method correlated well to CMR in experienced observers (ICC 0.85 and 0.86) but only moderately in less experienced observers (ICC 0.58 and 0.77) and was less reproducible in these observers (ICC = 0.55). Volumes were significantly underestimated compared with CMR (p < 0.001).

CONCLUSION

This study demonstrates that both RT3DE methodologies are sufficiently accurate and reproducible for use in daily practice. However, experience importantly influences the accuracy and reproducibility of the volumetric method, which should be considered when introducing this technique into clinical practice.

A pilot study of systolic dyssynchrony index by real-time three-dimensional echocardiography predicting clinical outcomes to surgical ventricular reconstruction in patients with left ventricular aneurysm

OBJECTIVES

The aim of the study was to detect whether the systolic dyssynchrony index (SDI) assessed by real-time 3D echocardiography (RT3DE) could predict clinical outcomes of patients with ventricular aneurysm in response to surgical ventricular reconstruction (SVR).

METHODS

In total, 120 individuals underwent RT3DE, including 30 healthy volunteers and 90 patients with ventricular aneurysm. All patients underwent clinical and echocardiographic assessments at baseline and at 12 months after SVR. The SDI was defined as the SD of time to minimum systolic volume of the 16 left ventricular (LV) segments, expressed in percent RR duration. SVR responder was defined as a >15% decrease in LV end-systolic volume, reduction in NYHA functional class or 20% relative increase in the LV ejection fraction (LVEF).

RESULTS

The SDI was significantly higher in patients with aneurysm, at 14.3% compared with 2.0% in healthy volunteers (P <0.047). The SDI was negatively correlated with the LVEF. After SVR, 86 patients were responders. In this patient subgroup, the SDI exhibited an immediate significant decrease (to 7.7%; P <0.034) and a progressive decrease during 12 months of follow-up (to 4.9%; P <0.044). The SDI can discriminate SVR responders. Receiver-operating characteristic curve analysis yielded cut-off values of SDI 14.3% best associated with SVR response; area under the curve was 0.79 with reduction in NYHA class, 0.86 with increase in EF and 0.66 with decrease in the end-systolic volume.

CONCLUSIONS

RT3DE can be used to assess LV mechanical dyssynchrony in patients with aneurysm. SVR produces a mechanical intraventricular resynchronization and SDI can predict improvement following SVR.

Tissue Doppler imaging in coronary artery diseases and heart failure

Recent studies have explored the prognostic role of TDI-derived parameters in major cardiac diseases, such as coronary artery disease (CAD) and heart failure (HF). In these conditions, myocardial mitral annular systolic (S’) and early diastolic (E’) velocities have been shown to predict mortality or cardiovascular events. In heart failure non invasive assessment of LV diastolic pressure by transmitral to mitral annular early diastolic velocity ratio (E/E’) is a strong prognosticator, especially when E/E’ is > or =15. Moreover, other parameters derived by TDI, as cardiac time intervals and Myocardial Performance Index, might play a role in the prognostic stratification in CAD and HF. Recently, a three-dimensional (3-D) TDI imaging modality, triplane TDI, has become available, and this allows calculation of 3-Dvolumes and LV ejection fraction. We present a brief update of TDI.

A new quantification method for mechanical dyssynchrony with three-dimensional echocardiography; segmental time and volume loss for prediction of response to cardiac resynchronisation therapy

A novel method to assess left ventricular (LV) mechanical dyssynchrony using three-dimensional echocardiography (3DE) and semi-automated border detection was investigated, which might be superior in prediction of response to cardiac resynchronisation therapy (CRT) compared to traditional measures that rely solely on segmental time-to-contraction. Twenty-eight heart failure patients underwent real-time 3DE before CRT and at 6–12 months follow-up. Analysis of 3DE was performed using TomTec Research-Arena software featuring semi-automated endocardial border detection. The following echocardiographic parameters were calculated in a 16-segment model: areas under segmental time-volume-curves (STV); delay between contraction of the earliest and latest segment (L-E); and standard deviation of segmental time-to-contraction (SDI). Response to CRT was defined as ≥10% decrease in LV end-systolic volume at follow-up. Baseline Pre-STV had a higher sensitivity than SDI for prediction of response (94 vs 67%, respectively), with equal specificity (78%) and a higher area under receiver operator characteristic curve. In contrast, L-E had a sensitivity of 83% and a specificity of 56%. Using 3DE, methods that combine segmental time-to-contraction with segmental contractility might improve LV dyssynchrony assessment compared to traditional methods based on segmental time-to-contraction alone. Pre-STV might be a better predictor of response to CRT than SDI.

Prediction of long-term outcome of cardiac resynchronization therapy by acute pressure-volume loop measurements

AIMS

Invasive assessment of acute haemodynamic response to biventricular pacing has been proposed as a tool to determine individual response and to optimize the effects of CRT. However, the long-term results of this approach have been poorly studied. The present study relates acute haemodynamic effects of CRT to long-term outcome.

METHODS AND RESULTS

Forty-one patients were analysed in the present study. During temporary biventricular pacing before implantation, acute changes in LV pump function were assessed by pressure-volume loop measurements and related to long-term response after CRT. In the study population [30 (71%) men, NYHA class 2.9 ± 0.4, EF 28 ± 7%, QRS 150 ± 25 ms], baseline mean stroke work (SW) and dP/dt(max) were 4.6 ± 2.6 L × mmHg and 874 ± 259 mmHg/s, respectively. During biventricular pacing, mean SW and dP/dt(max) increased significantly by 43 ± 39% (+ 2.2 ± 2.4 L × mmHg, P < 0.001) and 13 ± 18% (+ 96 ± 136 mmHg/s, P < 0.001), respectively. In long-term responders (n = 29, 71%) compared with non-responders (n = 12, 29%), the acute increase in SW was significantly higher (+57 ± 33% vs. + 10 ± 30%, P < 0.001), whereas the acute increase in dP/dt(max) was not significantly different between responders and non-responders (+ 15 ± 18% vs. 6 ± 15%, P = 0.139). Receiver operating characteristic (ROC) curve analysis indicated that SW was superior to dP/dt(max), QRS duration and LV dyssynchrony in prediction of response to CRT. A cut-off value for SW of 20% yielded a sensitivity of 90% and specificity of 75% to predict reverse remodelling at 6 months.

CONCLUSION

Invasive assessment of acute haemodynamics is a reliable tool to determine individual response to CRT. An acute increase in SW predicts long-term response to CRT with a higher accuracy than an acute increase in dP/dt(max), baseline QRS duration, and degree of LV mechanical dyssynchrony.

Advanced echocardiographic techniques

Echocardiography has advanced significantly since its first clinical use. The move towards more accurate imaging and quantification has driven this advancement. In this review, we will briefly focus on three distinct but important recent advances, three‐dimensional (3D) echocardiography, contrast echocardiography and myocardial tissue imaging. The basic principles of these techniques will be discussed as well as current and future clinical applications.

The impact of change in volume and left-ventricular hypertrophy on left-ventricular mechanical dyssynchrony in children with end-stage renal disease

Left-ventricular dyssynchrony (LVD) adversely affects systolic performance and has not been previously evaluated in children with end-stage renal disease (ESRD). We hypothesized (1) that LVD in children with ESRD would be significantly increased compared with controls and (2) that volume load and left-ventricular hypertrophy (LVH) would be associated with increased LVD. This was a prospective observational study in which real-time three-dimensional echocardiographic data were acquired in 27 stable children with ESRD (13 peritoneal dialysis [PD] and 14 hemodialysis [HD]) and 29 normal controls. Data were acquired before and after an HD session. Dyssynchrony index (SDI) was defined per standard formulae and was normalized to cardiac cycle duration (SDIp). Left-ventricular mass (LVM) was obtained from M-mode echocardiography and was normalized to height(2.7) (LVM index). The mean age (13.8 vs. 11.3 years) and SDI, SDIp, LVM, and LVM index were significantly greater among children with ESRD than among controls (p < 0.05). Demographics and heart rates were comparable between HD and PD subgroups, whereas SDI 16 and 12 segments, SDIp 16 segments, and LVM were significantly greater in the HD group. SDI and SDIp 16 segments improved after an HD session (p < 0.05); LVM and LVM index remained unchanged. LVD was significantly greater in patients with LVH compared with those without LVH. Children with ESRD had significant LVD and increased LVM compared with controls. Increased LVD in those undergoing HD rather than PD, as well as the improvement in synchrony after HD, suggest that volume may modulate LVD. LVD was increased in children with LVH. LVD in children with ESRD may have pathogenic implications.

Real-time three-dimensional echocardiographic evaluation of left ventricular systolic synchronicity in patients with chronic heart failure: comparison with tissue Doppler imaging

BACKGROUND

To investigate the clinical value of real-time three-dimensional echocardiography (RT-3DE) for assessing of left ventricular systolic synchronicity.

METHODS

Thirty healthy volunteers and 62 patients with congestive heart failure (CHF) were enrolled. The SD of time to peak systolic motion (TDI-Ts12-SD) was measured with tissue Doppler imaging in 12 myocardial segments. The SD and maximal difference of the time to minimal systolic volume (Tmsv) between 16, 12, or 6 myocardial segments, expressed as a percentage of cardiac cycle duration, were measured with RT-3DE and labeled Tmsv16-SD%, Tmsv12-SD%, Tmsv6-SD%, Tmsv16-D%, Tmsv12-D%, and Tmsv6-D%, respectively. The Spearman coefficient and Kappa value were calculated, and Bland-Altman analysis was performed to investigate the correlation and agreement between the two methods. Tmsv values were compared with ejection fraction (EF).

RESULTS

There was a moderately positive (p< 0.01) correlation between TDI-Ts12-SD and Tmsv16-SD%, Tmsv12-SD%, Tmsv16-D%, and Tmsv12-D% (r = 0.65, 0.64, and 0.65, respectively, with Kappa values of 0.66, 0.65, 0.72, and 0.74, respectively, p< 0.01). Tmsv16-SD%, Tmsv12-SD%, and Tmsv12-D% were significantly different between CHF patients with EF ≤ 35% and those with EF > 35%.

CONCLUSIONS

RT-3DE can be used in patients with CHF to quantify left ventricular mechanical dyssynchrony. Tmsv12-SD% and Tmsv12-D% were the best indices of left ventricular systolic synchronicity in relation to the severity of CHF as evaluated from EF.

New equation for prediction of reverse remodeling after cardiac resynchronization therapy

OBJECTIVES

To integrate data from two-dimensional echocardiography (2D ECHO), three-dimensional echocardiography (3D ECHO), and tissue Doppler imaging (TDI) for prediction of left ventricular (LV) reverse remodeling (LVRR) after cardiac resynchronization therapy (CRT). It was also compared the evaluation of cardiac dyssynchrony by TDI and 3D ECHO.

METHODS

Twenty-four consecutive patients with heart failure, sinus rhythm, QRS ≥ 120 msec, functional class III or IV and LV ejection fraction (LVEF) ≤ 0.35 underwent CRT. 2D ECHO, 3D ECHO with systolic dyssynchrony index (SDI) analysis, and TDI were performed before, 3 and 6 months after CRT. Cardiac dyssynchrony analyses by TDI and SDI were compared with the Pearson's correlation test. Before CRT, a univariate analysis of baseline characteristics was performed for the construction of a logistic regression model to identify the best predictors of LVRR.

RESULTS

After 3 months of CRT, there was a moderate correlation between TDI and SDI (r = 0.52). At other time points, there was no strong correlation. Nine of twenty-four (38%) patients presented with LVRR 6 months after CRT. After logistic regression analysis, SDI (SDI > 11%) was the only independent factor in the prediction of LVRR 6 months of CRT (sensitivity = 0.89 and specificity = 0.73). After construction of receiver operator characteristic (ROC) curves, an equation was established to predict LVRR: LVRR =-0.4LVDD (mm) + 0.5LVEF (%) + 1.1SDI (%), with responders presenting values >0 (sensitivity = 0.67 and specificity = 0.87).

CONCLUSIONS

In this study, there was no strong correlation between TDI and SDI. An equation is proposed for the prediction of LVRR after CRT. Although larger trials are needed to validate these findings, this equation may be useful to candidates for CRT.

Tissue Doppler, triplane echocardiography, and speckle tracking echocardiography: different ways of measuring longitudinal myocardial velocity and deformation parameters. A comparative clinical study

AIMS

The aim of our study was to compare global and segmental longitudinal myocardial velocity and deformation obtained from three different echocardiographic techniques of postprocessing analysis (two-dimensional tissue Doppler imaging (2D TDI), triplane tissue Doppler imaging (3D TDI), and speckle tracking echocardiography (STE)), in a group of consecutive subjects referred to echocardiography with different clinical indications, and to assess their reproducibility.

METHODS AND RESULTS

Standard echocardiograms with high frame rate gray-scale images and color coded TDI apical views, and a single beat TDI triplane apical section of the left ventricle were acquired at two different times. Longitudinal velocity and deformation parameters were obtained in postprocessing in 103 subjects from TDI and STE derived curves, and absolute values were compared to test the variability of the three techniques. All the measures were repeated twice, for a test-retest study. The times to peak velocity and deformation were similar by TDI and STE; other parameters showed significant difference (P < 0.05), both for global and segmental analysis. Reproducibility (expressed by the coefficient of variation and the coefficient of correlation r, in a large part of cases > 0.9) was acceptable, meaning that measures obtained at two different times did not differ significantly in between.

CONCLUSION

TDI and speckle tracking are both feasible and reproducible. Myocardial velocity and deformation parameters obtained with them are significantly different. STE is the most reproducible technique, whereas TDI based measurements are lower reproducible. STE can easily be used during clinical follow up for its feasibility and high reproducibility.

Biventricular Pacing in the Early Postoperative Period After Cardiac Surgery

Cardiac resynchronization therapy is not commonly used in the early postoperative period in patients undergoing cardiac surgery who have left ventricular (LV) dysfunction and a history of heart failure. We performed a prospective randomized clinical trial to compare atrial synchronous right ventricular (DDD RV) and biventricular (DDD BIV) pacing within 72 hours after cardiac surgery in patients with an EF ≤35 %, a QRS interval longer than 120 msec and who had LV dyssynchrony detected by real-time three-dimensional echocardiography (RT3DE). Epicardial pacing was provided by a modified Medtronic INSYNC III pacemaker. An LV epicardial pacing lead was implanted on the latest activated segment of the LV based on RT3DE. The study included 18 patients with ischemic heart disease, with or without valvular heart disease (14 men, 4 women, average age 71 years). Patients undergoing DDD BIV pacing had a statistically significant greater CO and CI (CO 6.7±1.8 l/min, CI 3.4±0.7 l/min/m²) than patients undergoing DDD RV pacing (CO 5.5±1.4 l/min, CI 2.8±0.7 l/min/m²), p<0.001. DDD BIV pacing in the early postoperative period after cardiac surgery corrects LV dyssynchrony and has better hemodynamic results than DDD RV pacing.

Three-dimensional echocardiographic characterization of left ventricular remodeling in Olympic athletes

The aim of the present study was to assess, using 3-dimensioanl echocardiography, the morphologic characteristics, determinants, and physiologic limits of left ventricular (LV) remodeling in 511 Olympic athletes (categorized in skill, power, mixed, and endurance sport disciplines) and 159 sedentary controls matched for age and gender. All subjects underwent 3-dimensional echocardiography for the assessment of LV volumes, ejection fraction, mass, remodeling index (LV mass/LV end-diastolic volume), and systolic dyssynchrony index (obtained by the dispersion of the time to minimum systolic volume in 16 segments). Athletes had higher LV end-diastolic volumes (157 ± 35 vs 111 ± 26 ml, p <0.001) and mass (156 ± 38 vs 111 ± 25 g, p <0.001) compared to controls. Body surface area and age had significant associations with LV end-diastolic volume (R(2) = 0.49, p <0.001) and mass (R(2) = 0.51, p <0.001). Covariance analysis showed that also gender and type of sport were significant determinants of LV remodeling; in particular, the highest impact on LV end-diastolic volume and mass was associated with male gender and endurance disciplines (p <0.001). Regardless of the type of sport, athletes had similar LV remodeling indexes to controls (1.00 ± 0.06 vs 1.01 ± 0.07 g/mL, p = 0.410). No differences were found between athletes and controls for the ejection fraction (62 ± 5% and 62 ± 5%, p = 0.746) and systolic dyssynchrony index (1.06 ± 0.40% and 1.37 ± 0.41%, p = 0.058). In conclusion, 3-dimensional echocardiographic morphologic and functional assessment of the left ventricle in Olympic athletes demonstrated a balanced adaptation of LV volume and mass, with preserved systolic function, regardless of specific disciplines participated.

Three-dimensional speckle tracking echocardiography for automatic assessment of global and regional left ventricular function based on area strain

OBJECTIVE

We evaluated the ability of a novel automatic index based on area strain to reliably quantify global and regional left ventricular (LV) function and accurately identify wall motion (WM) abnormalities using three-dimensional speckle tracking echocardiography.

METHODS

A total of 140 consecutive patients underwent two- and three-dimensional echocardiography. Segmental WM assessment by area strain was compared with visual assessment of two-dimensional images by two experienced echocardiographers. For global LV function assessment, area strain was validated against LV ejection fraction (EF) and wall motion score index (WMSI). Observer reliability was assessed in all patients, whereas test-retest reliability was evaluated in a subgroup of 50 randomly selected patients. Normal reference values of area strain were determined in 56 healthy subjects.

RESULTS

Agreement of WM scores between area strain and visual assessment was found in 94% of normal, 55% of hypokinetic, and 91% of akinetic segments (κ-coefficient 0.88). Sensitivity, specificity, and accuracy of area strain to distinguish abnormal segments from normal segments were 91%, 96%, and 94%, respectively. In regard to global LV function assessment, area strain was highly correlated with EF and WMSI (r = 0.91 and 0.88, respectively). Observer and test-retest reliability of area strain for quantitative assessment of global and regional LV function were good to excellent (all intraclass correlation coefficients ≥0.77). Intraobserver and interobserver reliability of semiquantitative segmental WM analysis by area strain (κ-coefficients 0.87 and 0.73) were comparable to visual assessment by experienced echocardiographers (0.85 and 0.69, respectively).

CONCLUSION

Area strain represents a promising novel automatic index that may provide an accurate and reproducible alternative to current echocardiographic standards for quantitative assessment of global and regional LV function. Area strain seems to adequately identify regional wall motion abnormalities compared with the clinical standard of visual assessment by experienced echocardiographers.

Three-dimensional echocardiography for left ventricular quantification: fundamental validation and clinical applications

One of the earliest applications of clinical echocardiography is evaluation of left ventricular (LV) function and size. Accurate, reproducible and quantitative evaluation of LV function and size is vital for diagnosis, treatment and prediction of prognosis of heart disease. Early three-dimensional (3D) echocardiographic techniques showed better reproducibility than two-dimensional (2D) echocardiography and narrower limits of agreement for assessment of LV function and size in comparison to reference methods, mostly cardiac magnetic resonance (CMR) imaging, but acquisition methods were cumbersome and a lack of user-friendly analysis software initially precluded widespread use. Through the advent of matrix transducers enabling real-time three-dimensional echocardiography (3DE) and improvements in analysis software featuring semi-automated volumetric analysis, 3D echocardiography evolved into a simple and fast imaging modality for everyday clinical use. 3DE provides the possibility to evaluate the entire LV in three spatial dimensions during the complete cardiac cycle, offering a more accurate and complete quantitative evaluation the LV. Improved efficiency in acquisition and analysis may provide clinicians with important diagnostic information within minutes. The current article reviews the methodology and application of 3DE for quantitative evaluation of the LV, provides the scientific evidence for its current clinical use, and discusses its current limitations and potential future directions.

Dyssynchrony Assessment with Tissue Doppler Imaging and Regional Volumetric Analysis by 3D Echocardiography Do Not Predict Long-Term Response to Cardiac Resynchronization Therapy

Background. Currently there are no reliable predictors of response to cardiac resynchronization therapy (CRT) before implantation. We compared pre-CRT left ventricular (LV) dyssynchrony by tissue Doppler imaging (TDI) and regional volumetric analysis by 3-dimensional transthoracic echocardiography (3DTTE) in predicting response to CRT. Methods. Thirty-eight patients (79% nonischemic cardiomyopathy) with symptomatic heart failure who underwent CRT were enrolled. Clinical and echocardiographic responses were defined as improvement in one NYHA class and reduction in LV end-systolic volume by ≥15% respectively. Functional status was assessed by Minnesota Living with Heart Failure questionnaire and 6-minute walk distance. Results. In 33 patients, after CRT for 7.86 ± 2.27 months, there were 24 (73%) clinical and 19 (58%) echocardiographic responders. Functional parameters, LV dimensions, volumes and synchrony by TDI and 3DTTE improved significantly in responders. There was no difference in the number of responders and nonresponders when cut-off values for dyssynchrony by different measurements validated in other trials were applied. Area under receiver-operating-characteristic curve ranged from 0.4 to 0.6. Conclusion. CRT improves clinical and echocardiographic parameters in patients with systolic heart failure. The dyssynchrony measurements by TDI and 3DTTE are not comparable and are unable to predict response to CRT.

Diffuse late gadolinium enhancement by cardiovascular magnetic resonance predicts significant intraventricular systolic dyssynchrony in patients with non-ischemic dilated cardiomyopathy

BACKGROUND

Left ventricular dyssynchrony and myocardial fibrosis are common findings in patients with nonischemic dilated cardiomyopathy (NDCM). The aim of this study was to investigate the association between myocardial fibrosis and intraventricular systolic dyssynchrony (DYS-sys) in patients with NDCM.

METHODS

Thirty-nine patients with NDCM and sinus rhythm were enrolled. Intraventricular DYS-sys was evaluated using Doppler tissue imaging, and cardiac fibrosis was assessed with cardiovascular magnetic resonance imaging with a 17-segment cardiac model. Each segment was graded on a 2-point scale (segmental fibrosis score): 0 = absence of late gadolinium enhancement, and 1 = presence of late gadolinium enhancement. A cardiac fibrosis index was calculated as 17/(17 - sum of fibrotic segments). Receiver operating characteristic analysis was performed to determine the utility of the cardiac fibrosis index to predict intraventricular systolic dyssynchrony.

RESULTS

Patients with DYS-sys had larger left atrial size (P = .004) and left ventricular end-systolic (P = .028) and end-diastolic (P = .034) volumes and lower tricuspid annular Doppler tissue imaging peak systolic velocities (P = .037) compared with patients without DYS-sys. A cardiac fibrosis index > or = 1.4 predicted significant DYS-sys with 92% sensitivity and 60% specificity (area under the receiver operating characteristic curve, 0.703; 95% confidence interval, 0.512-0.893; P = .035). Patients with cardiac fibrosis indexes > or = 1.4 (group 1) had larger left ventricular end-systolic (P = .044) and end-diastolic (P = .034) volumes than those with cardiac fibrosis indexes < 1.4 (group 2). Nine of 11 patients (82%) in group 1 and 6 of 28 patients (21%) in group 2 had significant DYS-sys (Pearson's chi(2) = 12.169, P < .0001). Logistic regression analysis revealed that cardiac fibrosis index > or = 1.4 (odds ratio, 11.2; 95% confidence interval, 1.72-71.4; P = .012) was an independent predictor of DYS-sys.

CONCLUSION

Patients with NDCM and prominent cardiac fibrosis have significant DYS-sys. The cardiac fibrosis index is a useful tool to predict DYS-sys.

Automated border detection in three-dimensional echocardiography: principles and promises

Several automated border detection approaches for three-dimensional echocardiography have been developed in recent years, allowing quantification of a range of clinically important parameters. In this review, the background and principles of these approaches and the different classes of methods are described from a practical perspective, as well as the research trends to achieve a robust method.