Evaluation of left atrial and left ventricular functions with 3D speckle-tracking echocardiography in patients with coronary artery tortuosity.

BACKGROUND: Tortuosity in the coronary arteries is a very common entity encountered during angiography. The effect of coronary artery tortuosity (CAT) on the myocardium has not been completely investigated. The aim of the current study was to assess the effects of CAT on left atrial (LA) and left ventricular (LV) myocardial functions by 3D speckle-tracking echocardiography (3D-STE). METHODS: Seventy-five patients with CAT and 80 age- and gender-matched controls who proved to have normal coronary angiograms (CAG) were enrolled into the study. Following CAG, the 2D images were obtained first, and then 3D images were obtained for strain analysis. RESULTS: The LAS-r, LAS-active, and LV-GLS were significantly depressed in the CAT (+) group (p < .001, p < .001, p = .012, respectively). The multivariate regression models demonstrated that LAS-r (p < .001), LAS-active (p = .009), and LV-GLS (p = .024) were found to be independent factors predicting CAT. CONCLUSION: The current study is the first to focus on the assessing both LA and LV myocardial dynamics in CAT (+) patients by strain echocardiography. The results of our study support the patients with CAT may have subclinical LA and LV myocardial involvements.

Demonstration of subclinical left ventricular electrical and mechanical dysfunction in overweight subjects by frontal QRS-T angle and 3D-speckle tracking echocardiography.

BACKGROUND: Overweightness is a considerable step in the process leading to obesity. There are no sufficient studies on the effect of cardiomyopathy defined in obese patients about overweight subjects. We thought that it may be useful to examine the myocardial involvement in overweight individuals electro-mechanically with more sensitive techniques before the development of obesity cardiomyopathy. AIM: The aim of the present study was to demonstrate whether or not there are subclinical left ventricular (LV) electrical and mechanical dysfunctions in overweight patients using frontal QRS-T (fQRS-T) angle (electrically) and 3D-speckle tracking echocardiography (mechanically). METHODS: A total of 80 overweight patients and 80 age- and sex-matched normal weight individuals were enrolled into the study. 3D-STE examinations of the patients were performed. Electrocardiographic recordings were obtained for fQRS-T angle assessment. RESULTS: The LV-GLS and LV-GCS were significantly depressed in the overweight group than in the normal weight group (-14.5 ± 3.4 vs. -21.7 ± 3.6, p < .001; -15.2 ± 4.6 vs. -24.3 ± 4.8, p < .001, respectively). The fQRS-T angle was found to be increased in the overweight group (142.5 ± 39.2 vs. 114.7 ± 43.5, p = < .001). Statistically significant positive linear correlations were observed between BMI with LV-GLS, LV-GCS, and fQRS-T angle. LV-GLS and LV-GCS were found to be disrupted linearly as BMI increased (r = .718 for BMI and LV-GLS, r = .653 for BMI and LV-GCS). As BMI increased, it was found that the fQRS-T angle increased (r = .692 for BMI and fQRS-T angle). CONCLUSION: Our results support that, overweight individuals, despite their being apparently healthy, may have subclinical LV myocardial mechanical and electrical dysfunction.

Association of left ventricular global area strain derived from resting 3D speckle-tracking echocardiography and exercise capacity in individuals undergoing treadmill exercise test.

Background: Left ventricular (LV) global area strain (GAS) is a novel index derived from resting 3D speckle-tracking echocardiography (STE), and its clinical significance has rarely been studied. We examined the association of LV GAS and exercise capacity in a health check-up population. Methods: We recruited 94 symptom-free participants (52.2 ± 11.7 years, 62.8% male) without substantial structural heart disease or coronary heart diseases who were undergoing a routine health examination. All participants underwent resting echocardiography and symptom-limited treadmill exercise test according to the Bruce protocol. Four strain parameters were obtained from the analysis, namely 3D GAS (GAS3d), global longitudinal strain, global circumferential strain, and global radial strain. Results: After multivariate analysis for factors of exercise time, we observed a significant association in LV GAS3d (P < 0.001). We divided participants into preserved and impaired exercise capacity groups according to the cutoff value of 8 metabolic equivalent of tasks. LV GAS3d (OR 1.24, 95% CI 1.10-1.39, P < 0.001) was an independent predictor of impaired exercise capacity and the optimal cut-off value was -19.96% at a sensitivity of 77.8% and at a specificity of 92.1%. LV GAS3d could improve the discriminatory power of exercise capacity in individuals with early mitral filling velocity to average mitral annulus velocity ratio (E/e') ≥ 8. Conclusions: LV GAS3d was significantly associated with exercise time and exhibited incremental predictive value on E/e' for exercise capacity in participants undergoing treadmill exercise test.

Evaluation of left atrial and left ventricular functions in patients with Wolff-Parkinson-White syndrome before and after radiofrequency catheter ablation using three-dimensional speckle tracking echocardiography.

BACKGROUND: Wolff-Parkinson-White (WPW) syndrome is one of the most common congenital cardiac abnormalities among ventricular pre-excitation syndromes. Radiofrequency catheter ablation (RFCA) treatment of accessory pathways (APs) in WPW patients is an established curative therapy restoring normal atrioventricular conduction. We have not encountered any studies evaluating both the LA and LV functions of these patients before and after RFCA with three dimensional-speckle tracking echocardiography (3D-speckle tracking echocardiography (STE)). AIM: The purpose of the current study was to assess the LA and LV functions in patients with WPW syndrome before and after RFCA using 3D-STE. METHODS: A total of 21 patients with WPW syndrome who had been scheduled for RFCA were prospectively recruited for this study. 3D-STE examinations of the patients were performed 12-24 h before ablation and 1 month after ablation. RESULTS: The LV-global longitudinal strain (LV-GLS) and LV-global circumferential strain (LV-GCS) were significantly depressed in the pre-RFCA WPW group than in the control group (-14.3 ± 2.1 vs. -21.5 ± 2.2, p < .001; -12.6 ± 1.8 vs. -20.4 ± 1.8, p < .001, respectively). The left atrial strain-reservoir (LAS-r) and LAS-active were significantly decreased in the pre-RFCA WPW group than in the control group (31.9 ± 2.4 vs. 48.8 ± 2.6, p < .001; 11.7 ± 2 vs. 26.5 ± 2.1, p < .001, respectively). The LV-GLS, LV-GCS, LAS-r, and LAS-active values improved after RFCA compared to before. CONCLUSION: The results of our study indicated that there are subclinical impairments in LV and LA myocardial dynamics in the apparently healthy WPW patients, and these deteriorations improve after RFCA of AP.

The Prognostic Value of Left Atrial Reservoir Functional Indices Measured by Three-Dimensional Speckle-Tracking Echocardiography for Major Cardiovascular Events.

BACKGROUND: Left atrial (LA) volume and left ventricular longitudinal strain (LVLS) have significant prognostic values for major cardiovascular events (MACEs). Prognostic values of LA reservoir functional indices measured by 3-dimensional (3D) speckle-tracking echocardiography (STE) were evaluated.Methods and Results:A total of 264 patients, who underwent 2-dimensional (2D) echocardiography and 3DSTE for various underlying heart diseases, were followed up to record MACE. After a mean follow up of 547±435 days, 30 patients developed MACE: 7 cardiac deaths, 6 strokes, 1 non-fatal myocardial infarction, and 22 admissions for heart failure (5 of these had cardiac death after discharge, whereas 1 sustained stroke after discharge). Receiver operating characteristic curve analysis was performed to determine the optimal cut-off levels of 4 LA functional indices: LA emptying fraction (LAEmpF), LA longitudinal strain (LALS), LA circumferential strain (LACS), and LA area change ratio (LAAC), using 3DSTE. Among these factors, 2DLVLS, 3DLAEmpF, and 3DLALS demonstrated a higher hazard ratio (>5.0) than other variables. The 3DLAEmpF and 3DLALS had a higher average treatment effect (ATE) and ATE on the treated (ATT), respectively, than the other indices after propensity score matching. Addition of 3DLAEmpF to the base model using clinical variables and LV ejection fraction or 2DLVLS demonstrated higher prognostic power. CONCLUSIONS: LAEmpF calculated using 3DSTE possessed additive prognostic values for the prediction of MACE.

Left Ventricular Torsion　- A New Echocardiographic Prognosticator in Patients With Non-Ischemic Dilated Cardiomyopathy.

BACKGROUND: Left ventricular (LV) torsion is a key parameter in cardiac function and predicts functional capacity (FC) more appropriately than LV ejection fraction (EF). We sought to investigate LV torsion as a marker of hospitalization for worsening heart failure (HF) in non-ischemic dilated cardiomyopathy (DCM) patients. Methods and Results: The 91 outpatients with newly diagnosed DCM (53±13 years, 20% female) were evaluated with 3D speckle-tracking imaging and followed up for 12 months; 43 healthy sex- and age-matched volunteers served as controls. LV torsion, LVEF, right ventricular function, LV global longitudinal (GLS) and circumferential (GCS) strain values, peak oxygen uptake (peak V̇O2) from FC and B-type natriuretic peptide levels were measured at baseline. Peak V̇O2correlated successively with LV torsion, diastolic filling and GCS (r=0.70, -0.52 and -0.41, P<0.01) disclosing the central role of LV torsion. During follow-up (median 272 days), 24 (26%) cardiac events occurred. A reduced LV torsion (<0.59 degrees/cm) predicted cardiac events similar to a reduced peak V̇O2(<19 mL/kg/min) (unadjusted hazard ratio 6.41 and 5.90, P<0.001). LV torsion provided a significant incremental value over right ventricular function and peak V̇O2(C-index: 0.85, P=0.02). CONCLUSIONS: The results demonstrated a clear relation between LV torsion and disease severity, suggesting that LV torsion has additional prognostic relevance in DCM patients.

Prognostic Value of Left Atrial Size and Functional Indices Measured by 3-Dimensional Speckle-Tracking Analysis.

BACKGROUND: The prognostic value of indices for left atrial volumes (LAV) and reservoir function measured by 3D speckle-tracking analysis (3DSTA) has not been determined. Methods and Results: LA maximal and minimal volume indices (LAVImax, LAVImin), and LA emptying fraction (LAEmpF) were measured via 2D echocardiography (2DE) and 3DSTA in 514 patients (62% male, mean age: 66±15 years) with various cardiovascular diseases. Two cutoff values using normal±2SD (cutoff criterion 1) and receiver-operating characteristic analysis (cutoff criterion 2) were evaluated. During a mean follow-up of 720±383 days, MACE (cardiac death, nonfatal myocardial infarction, stroke and admission for heart failure) occurred in 98 patients. Kaplan-Meier survival analysis showed both cutoff criteria measured by 2DE and 3DSTA had significant predictive power for MACE (P<0.001). For cutoff criterion 1, 3DSTA measurements yielded higher hazard ratios than 2DE by Cox proportional hazard model. Cutoff criterion 2 using 3DSTA had higher average treatment effect values than 2DE by matching propensity scores on the outcome. Further, a regression model that included clinical variables, left ventricular ejection fraction and cutoff criterion 2 using 3DSTA-derived LAEmpF had significantly higher prognostic power than 2DE. CONCLUSIONS: LA indices measured by 3DSTA had greater prognostic power for future MACE than 2DE. In particular, 3DSTA-derived LAEmpF has the potential to be a valuable prognostic tool in clinical settings.

Identification of significant coronary artery disease in patients with non-ST segment elevation acute coronary syndrome by myocardial strain analyses using three dimensional speckle tracking echocardiography.

BACKGROUND: Speckle-tracking imaging is a novel method for assessing left ventricular function and ischemic changes. This study aimed to predict the presence of significant coronary artery stenosis in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) by 3D strain analysis using speckle tracking echocardiography (3DSTE) at rest. METHODS: This cross-sectional study included a total 60 patients with NSTE-ACS who underwent 3DSTE immediately prior to coronary angiography. Subsequently, patients undergone coronary angiogram (CAG) and divided into two groups; group- I: significant stenosis (n = 36), group-II: non-significant stenosis (n = 24). RESULTS: Global peak systolic longitudinal strain (GPSLS), circumferential strain (CS), area strain (AS), and radial strain (RS) were obtained successfully in 60 patients. All strain parameters were significantly reduced in patient group of significant stenosis. Receiver operating characteristic (ROC) curve analysis demonstrated that GPSLS could effectively detect patients with significant stenosis (area under ROC curve = 0.840, 95% CI = 0.735-0.945). GPSLS with a cutoff value of -13.50% showed good sensitivity and specificity for predicting significant stenosis (sensitivity 88.9% and specificity 70.8%). CONCLUSION: Global peak systolic longitudinal strain using 3D speckle tracking echocardiography at rest was significantly lower in patients with significant stenosis and might be useful for identifying patients with a significant stenosis with good degree of sensitivity and specificity.

Cardiac function on 3-D speckle tracking imaging and cytokines in Kawasaki disease.

BACKGROUND: Serum N-terminal pro-brain natriuretic peptide (NT-proBNP) tends to rise in acute phase Kawasaki disease (KD), but the cause of NT-proBNP elevation has not been clarified. In a previous study, cardiac function evaluated on 2-D echocardiography (2D-E) such as ejection fraction was normal, but this does not reflect subtle changes in cardiac dysfunction, and hence the association between cardiac function and NT-proBNP elevation is still controversial. The aim of this study was therefore to elucidate the influence of cardiac function on NT-proBNP elevation, by evaluating cardiac function via strain on 3-D speckle tracking imaging (3D-STI), in acute and subacute KD patients. Given that cytokines are also thought to induce NT-proBNP in acute phase KD, serum cytokines and cytokine receptors were measured at the same time. METHODS: Laboratory data and echocardiography in 52 KD patients in the acute and subacute phases were reviewed. RESULTS: Median NT-proBNP was significantly elevated in the acute phase compared with the subacute phase (356.5 pg/mL; IQR, 145-904 pg/mL vs 103.5 pg/mL; IQR, 59-150 pg/mL, P < 0.01). All cytokines were also significantly elevated in the acute phase compared with the subacute phase. Tumor necrosis factor (TNF)-α, soluble TNF receptor (sTNFR)1, and sTNFR2 concentration were all significantly higher in the acute phase. Indices of cardiac function were not significant different between phases. NT-proBNP in the acute and subacute phases correlated with sTNFR1 (r = 0.63/0.43, P < 0.01), sTNFR2 (r = 0.50/0.31, P < 0.05), and interleukin-6 (r = 0.58/0.43, P < 0.01). NT-proBNP did not correlate with global longitudinal strain (GLS) on 3D-STI. CONCLUSION: Although no correlation was seen between NT-proBNP and GLS on 3D-STI, correlations between NT-proBNP and cytokines were clear. NT-proBNP might be a marker of inflammation in KD, but is not a marker of cardiac function.

Comparison of two-dimensional and three-dimensional echocardiographic strain in children with CHD.

BACKGROUND: In CHD, three-dimensional strain analysis may overcome limitations of Doppler and two-dimensional strain of the left ventricle. The aims of this study were to evaluate feasibility and reproducibility of three-dimensional longitudinal, circumferential, and radial systolic strain by three-dimensional speckle-tracking echocardiography compared with two-dimensional echocardiography. METHODS: Patients with CHD, biventricular circulation with a systemic left ventricle, and who had two- and three-dimensional imaging performed on the same day from 2010 to 2014 were included. Quantitative two- and three-dimensional strain analyses were performed (two-dimensional cardiac performance analysis version 1.2 and four-dimensional left ventricular analysis version 3.1). Intra- and inter-observer variabilities were calculated on 25 studies. RESULTS: A total of 30 patients, including 19 (61%) males, with a median age of 3.6 years (0.1-22 years) were included. The mean fractional shortening was 34.6±5.3%, and the mean ejection fraction was 62.0±6.4%. Measurement of two- and three-dimensional strain was feasible in >95% of segments. Good correlation was observed between longitudinal and circumferential strain (r=0.92, p⩽0.001 and r=0.87, p⩽0.001), but not radial strain (r=0.29, p=0.2). Intra- and inter-observer agreements were better for three-dimensional compared with two-dimensional strain, and better for both two- and three-dimensional longitudinal and circumferential strains compared with radial strain. CONCLUSION: Left ventricular three-dimensional strain analysis is feasible in children with CHD. The reproducibility of longitudinal and circumferential strain by three-dimensional analyses is better. Further longitudinal studies are warranted for the potential clinical application of this new technology.

Left ventricular subclinical dysfunction associated with myocardial deformation changes in obstructive sleep apnea patients estimated by real-time 3D speckle-tracking echocardiography.

BACKGROUND: Previous studies have demonstrated that patients with obstructive sleep apnea (OSA) may develop left ventricular (LV) diastolic dysfunction. We aimed to study whether OSA patients have LV regional systolic dysfunction with myocardial deformation changes, despite a normal LV ejection fraction, using real-time 3D speckle-tracking echocardiography (Rt3D-STE). METHODS: Seventy-eight patients with OSA and no comorbidities were studied. They were divided into the following three groups according to the apnea-hypopnea index (AHI): 5~15/h as group I (mild OSA, 26 cases), 15~30/h as group II (moderate OSA, 29 cases), and ≥30/h as group III (severe OSA, 23 cases). Thirty gender-age-matched normal subjects were included as controls. The parameters of LV diastolic function were acquired with traditional echocardiography. The LV myocardial deformation parameters were obtained, including the longitudinal (LS), circumferential (CS), radial (RS), and area (AS) strains, with Rt3D-STE. RESULTS: LV global systolic function was normal in all patients, but diastolic function was impaired in groups II and III (E/E' was 9.6 ± 2.8 and 10.4 ± 2.5, respectively, p < 0.0001). The global LS and AS were significantly reduced in groups II and III compared with the controls and group I (LS 15.9 ± 1.4 % and 14.8 ± 1.5 % vs 18.2 ± 1.7 % and 17.8 ± 1.5 %; AS 27.4 ± 1.8 % and 24.9 ± 2.3 % vs 33.4 ± 2.2 % and 32.7 ± 2.9 %, respectively, p < 0.0001), but the global CS and RS were significantly reduced only in group III (17.3 ± 1.4 % and 43.1 ± 6.5 % vs 19.6 ± 1.6 % and 55.4 ± 4.0 %, respectively, <0.0001). The severity of OSA was significantly associated with the LV global AS value (r = -0.80, p < 0.0001), LS (r = -0.64, p < 0.0001), CS (r = -0.51, p < 0.0001), and RS (r = -0.62, p < 0.0001). CONCLUSIONS: Patients with moderate and severe OSA tended to have both LV diastolic dysfunction and abnormalities in regional systolic function with myocardial deformation changes, in spite of the normal LV ejection fraction. Myocardial strains of the LV were negatively correlated with the AHI. Rt-3DST had important clinical significance in the early evaluation of cardiac dysfunction in OSA patients.

Role of Three-Dimensional Speckle Tracking Echocardiography in the Quantification of Myocardial Iron Overload in Patients with Beta-Thalassemia Major.

BACKGROUND: The new three-dimensional speckle tracking echocardiography (3DSTE) may enable comprehensive quantification of global left ventricular (LV) myocardial mechanics. METHODS: Twenty-four patients aged 29.3 ± 5.2 years and 22 controls were studied. 3DSTE was performed to assess LV 3D global strain, twist and torsion, ejection fraction, and systolic dyssynchrony index (SDI). The LV SDI was calculated as % of SD of times-to-peak strain of 16 segments/RR interval. The global performance index (GPI) was calculated as (global 3D strain·torsion)/SDI. Area under the receiver operating characteristic curve (AUC) was calculated to determine the capability of 3DSTE parameters to discriminate between patients with (cardiac magnetic resonance T2* <20 ms) and those without myocardial iron overload. RESULTS: Compared with controls, patients had significantly lower LV global 3D strain (P < 0.001), twist (P = 0.01), torsion (P = 0.04), and ejection fraction (P < 0.001) and greater SDI (P < 0.001). The GPI was lower in patients than controls (P < 0.001). T2* value correlated positively with global 3D strain (r = 0.74, P < 0.001) and GPI (r = 0.63, P = 0.001), and negatively with SDI (r = -0.44, P = 0.03). The AUCs of GPI, global 3D strain, ejection fraction, torsion, and 1/SDI were 0.94, 0.90, 0.87, 0.82, and 0.70, respectively. The GPI cutoff of 2.7°/cm had a sensitivity of 94.9% and a specificity of 88.9% of differentiating patients with from those without myocardial iron overload. CONCLUSIONS: The LV composite index of strain, torsion, and dyssynchrony derived from 3DSTE enables sensitive detection of myocardial iron overload in patients with thalassemia.

Left ventricular mechanics in adolescents and young adults with a history of kawasaki disease: analysis by three-dimensional speckle tracking echocardiography.

BACKGROUND: Myocardial fibrosis and perfusion abnormalities can occur in patients with Kawasaki disease (KD). We explored using the new three-dimensional speckle tracking echocardiography (3DSTE) the left ventricular (LV) mechanics in adolescents and young adults with a history of KD. METHODS: Twenty-five KD patients (18 males) aged 17.0 ± 5.2 years, 14 with (group I) and 11 without (group II) coronary aneurysms, were studied. The 3D volume datasets were acquired for quantification of LV global 3D strain, global and regional area strain, systolic dyssynchrony index (SDI), twist, twist gradient (twist/LV length), and ejection fraction. RESULTS: The results were compared with those of 14 age-matched controls. Of the 14 group I patients, 6 had left, 2 had right, and 6 had both left and right coronary aneurysms. Compared with controls, group I patients had significantly lower LV systolic global 3D strain (43.7 ± 7.3% vs. 50.4 ± 6.6%, P = 0.02), twist (8.7 ± 1.3° vs. 11.4 ± 2.0°, P < 0.001), and twist gradient (1.5 ± 0.3°/cm vs. 1.9 ± 0.4°/cm, P = 0.01), greater SDI (6.8 ± 1.9% vs. 4.7 ± 1.9%, P < 0.001), and similar ejection fractions. Six patients in group I had perfusion defects, who had global 3DSTE parameters similar to those of the 8 patients without perfusion abnormalities (all P > 0.05). For group II patients, only the global area strain was significantly lower than that of controls (37.6 ± 3.5% vs. 40.7 ± 3.6%, P = 0.038). CONCLUSION: In adolescents and young adults with a history of KD, impairment of LV mechanics occurs and is worse in patients with than those without coronary complications.

Elucidating the mechanisms underlying left ventricular function recovery in patients with ischemic heart failure undergoing surgical remodeling: A 3-dimensional ultrasound analysis.

OBJECTIVE: The study objective was to elucidate the mechanisms of left ventricle functional recovery in terms of endocardial contractility and synchronicity after surgical ventricular reconstruction. METHODS: Real-time 3-dimensional transthoracic echocardiography was performed on 20 patients with anterior left ventricle remodeling and ischemic heart failure before surgical ventricular reconstruction and at 6-month follow-up, and on 15 healthy controls matched by age and body surface area. Real-time 3-dimensional transthoracic echocardiography datasets were analyzed through TomTec software (4D LV-Analysis; TomTec Imaging Systems GmbH, Unterschleissheim, Germany): Left ventricle volumes, ejection fraction, and global longitudinal strain were computed; the time-dependent endocardial surface yielded by 3-dimensional speckle-tracking echocardiography was postprocessed through in-house software to quantify local systolic minimum principal strain as a measure of fiber shortening and mechanical dispersion as a measure of fiber synchronicity. RESULTS: Compared with controls, patients with heart failure before surgical ventricular reconstruction showed lower ejection fraction (P < .0001) and significantly impaired mechanical dispersion (P < .0001) and minimum principal strain (P < .0001); the latter worsened progressively from left ventricle base to apex. After surgical ventricular reconstruction, global longitudinal strain improved from -6.7% to -11.3% (P < .0001); mechanical dispersion decreased in every left ventricle region (P ≤ .017) and mostly in the basal region, where computed mechanical dispersion values were comparable to physiologic values (P ≥ .046); minimum principal strain improved mostly in the basal region, changing from -16.6% to -22.3% (P = .0027). CONCLUSIONS: At 6-month follow-up, surgical ventricular reconstruction was associated with significant recovery in global left ventricle function, improved mechanical dispersion indicating a more synchronous left ventricle contraction, and improved left ventricle fiber shortening mostly in the basal region, suggesting the major role of the remote myocardium in enhancing left ventricle functional recovery.

Backscatter tensor imaging and 3D speckle tracking for simultaneous ex vivo structure and deformation measurement of myocardium.

OBJECTIVE: Biaxial mechanical testing is a common method for elucidation of mechanical properties of excised ventricular myocardium, especially in the context of structural remodeling that accompanies heart disease. Current imaging strategies in biaxial testing are based on optical camera imaging of the tissue surface, thus providing no information about the tissue microstructure and limiting strain measurements to two dimensions. Here, these limitations are overcome by replacing the camera with ultrasound imaging in order to measure both transmural fiber orientation and 3D tissue deformation during biaxial testing. METHODS: Quasi-static biaxial mechanical testing is applied to four samples of excised porcine ventricular myocardium (two left- and two right-ventricular tissues). During testing, a rotational scan of an ultrasound linear array provides data for both backscatter tensor imaging and 3D speckle tracking, from which transmural fiber orientation and tissue deformation are computed, respectively. Ultrasound-derived fiber orientation and tissue strain are validated against histology and camera surface imaging, respectively. DISCUSSION: Ultrasound-derived fiber angle and tissue strain exhibit good accuracy, with root-mean-square errors of 9.9° and 1.2% strain, respectively. Further investigation into the optimization of backscatter tensor imaging is warranted. Replacing the rotational scan of a linear array with volume imaging with a matrix array will improve the technique. CONCLUSION: Ultrasound imaging can replace the optical camera measurement during biaxial mechanical testing of ventricular myocardium in order to accurately provide measurements of transmural fiber orientation and tissue strain. In situ knowledge of transmural fiber structure and tissue deformation can enhance the inverse problem used to determine tissue mechanical properties from biaxial testing.

Left Atrial Remodeling in Patients With Severe Rheumatic Mitral Stenosis and Sinus Rhythm Using Two-Dimensional and Three-Dimensional Speckle Tracking Echocardiography.

Background: In mitral stenosis (MS), the combination of an increase in left atrium (LA) pressure and atrial inflammatory response is accompanied by increase in interstitial fibrosis of the atrial wall with disorganization of atrial muscle bundles, LA dysfunction and subsequently LA dilatation. We aimed to assess the effect of severe rheumatic MS on LA volumes and mechanics. Methods: We enrolled 40 patients with pure severe rheumatic MS and sinus rhythm as a patient group and 30 healthy subjects as a control group. All patient and control groups underwent two-dimensional (2D) transthoracic echo to measure left ventricle (LV) dimensions, function, LA deformations, estimated systolic pulmonary artery pressure (EPAP), and left ventricle global longitudinal strain (LV GLS). Also LA volumes and mechanics (LA strain during LV systole (reservoir function) and LV diastole (early = conduit, and late = booster pump = atrial contraction)) were measured by three-dimensional (3D) transthoracic echo; mitral valve (MV) area was measured by 3D transesophageal echo (as routine pre-percutaneous MV commissurotomy using multiplanar reconstruction in mid-esophageal apical long-axis view from LA prospective). Results: By 2D transthoracic echo, patient group revealed significantly lower all LA function vs. control group including LA strain during reservoir (24 ± 6 vs. 43 ± 3, P < 0.001), LA strain during conduit (-11 ± 3 vs. -25 ± 2, P < 0.001), and during booster pump (-13 ± 4 vs. -18 ± 1, P < 0.001). EPAP was significantly higher in patient group (48 ± 7 vs. 27 ± 4 in control group). LV GLS was significantly lower in patient group (-16±2% vs. -23±2% in control group). All 3D LA volumes were significantly higher in patient group than control group including maximum LA volume (LAVmax) (76 ± 18 vs. 50 ± 5, P < 0.001), indexed LA volume (LAVi) (44.6 ± 10.1 vs. 28.7 ± 3.7, P < 0.001), LV minimum volume (LAVmin) (51 ± 15 vs. 30 ± 4, P < 0.001), and LA volume pre atrial contraction (LAVpre A) (63 ± 15 vs. 41 ± 6, P < 0.001). Also, there was significantly decreased LA strain using 3D speckle tracking echo in patient group including systolic deformation of LA (reservoir function) (23 ± 6 vs. 41 ± 3, P < 0.001) and diastolic deformation, early diastole (conduit function) (-10 ± 2 vs. -24 ± 2, P < 0.001), and late diastole (booster pump function) (-13 ± 4 vs. -18 ± 1, P < 0.001). Conclusions: All LA function markedly reduced in pure severe rheumatic MS. The reduction of LA mechanics is directly related to the degree of reduction of the stenotic MV area. LV GLS significantly reduced in severe MS and its reduction is directly related to the degree of reduction of the stenotic MV area and the LAVi by 3D echo.

3D Atrial Strain for Predicting Recurrence of Atrial Fibrillation after Pulmonary Vein Isolation.

AIMS: Association of two-(2D) and three-dimensional (3D) left atrial strain (LAS) and low-voltage area (LVA) with recurrence of atrial fibrillation (AF) after pulmonary vein isolation (PVI) was assessed. METHODS AND RESULTS: 3D LAS, 2D LAS, and LVA were obtained in 93 consecutive patients undergoing PVI and recurrence of AF was analyzed prospectively. AF recurred in 12 patients (13%). The 3D left atrial reservoir strain (LARS) and pump strain (LAPS) were lower in patients with recurrent AF than without (p = 0.008 and p = 0.009, respectively). In univariable Cox regression, 3D LARS or LAPS were associated with recurrent AF (LARS: HR = 0.89 (0.81-0.99), p = 0.025; LAPS: HR = 1.40 (1.02-1.92), p = 0.040), while other values were not. Association of 3D LARS or LAPS with recurrent AF was independent of age, body mass index, arterial hypertension, left ventricular ejection fraction, and end-diastolic volume index and left atrial volume index in multivariable models. Kaplan-Meier curves revealed that patients with 3D LAPS < -5.9% did not exhibit recurrent AF, while those >-5.9% had a significant risk of recurrent AF. CONCLUSIONS: 3D LARS and LAPS were associated with recurrent AF after PVI. Association of 3D LAS was independent of relevant clinical and echocardiographic parameters and improved their predictive value. Hence, they may be applied for outcome prediction in patients undergoing PVI.

Early Change in Area Strain Detected by 3D Speckle Tracking Is Associated With Subsequent Cardiotoxicity in Patients Treated With Low Doses of Anthracyclines.

Objective: To evaluate the prognostic impact of the parameters of myocardial deformation using three-dimensional speckle tracking echocardiography (3DSTE) in patients with breast cancer who underwent chemotherapy with low doses of anthracyclines. Background: Chemotherapy-related cardiotoxicity has an important prognostic impact on cancer survivors. Three-dimensional STE has revealed more consistent data than two-dimensional techniques and may represent a more accurate tool in the evaluation of myocardial function in patients who underwent chemotherapy. Methods: We evaluated patients with breast cancer who were treated with anthracyclines (associated or not with trastuzumab) in five stages: baseline, after cumulative doses of 120 and 240 mg/m2 of doxorubicin, and then, after 6 months and at least 1 year after anthracyclines. Ultrasensitive troponin I (US-TnI) and a standard echocardiography study were performed at each stage. We analyzed left ventricular ejection fraction (LVEF) by Simpson's method, two-dimensional speckle tracking (2DSTE) with longitudinal and radial strain values, and 3DSTE with longitudinal, radial, and circumferential strain as well as twist, torsion, rotation, and three-dimensional global area strain (3DGAS). Cardiotoxicity was defined as a decrease in LVEF by more than 10 percentage points to a value lower than 53%. Results: We evaluated 51 female patients who were aged 50.6 ± 11 years. After the cumulative dose of 240 mg/m2 of doxorubicin, US-TnI was increased (>34 pg/ml) in 21 patients (45%, p > 0.001), LVEF remained unchanged (p = 0.178), while 2DSTE longitudinal strain was decreased (from -17.8% to -17.1%, p < 0.001) and 3DSTE detected changes in longitudinal, radial, circumferential, and area strain. After a lower cumulative dose of doxorubicin (120 mg/m2), 3DGAS (p < 0.001) was the only parameter that was changed. In the follow-up, 7 (13%) patients presented a decrease in LVEF. Three-dimensional GAS early changed to abnormal values was the only variable associated with a subsequent decrease in LVEF (definitive cardiotoxicity). Conclusion: In patients with breast cancer, 3DSTE detected early changes in area strain after very low doses of doxorubicin. The 3DGAS early changed to abnormal values was associated with a subsequent decrease in LVEF, representing a promising technique to predict chemotherapy-induced cardiomyopathy.

3D-speckle-tracking echocardiography correlates with cardiovascular magnetic resonance imaging diagnosis of acute myocarditis - An observational study.

Background: The diagnostic importance of three-dimensional (3D) speckle-tracking strain-imaging echocardiography in patients with acute myocarditis remains unclear. The aim of this study was to test the diagnostic performance of 3D-speckle-tracking echocardiography compared to CMR (cardiovascular magnetic resonance imaging) for the diagnosis of acute myocarditis. Methods and results: 45 patients with clinically suspected myocarditis were enrolled in our study (29% female, mean age: 43.9 ± 16.3 years, peak troponin I level: 1.38 ± 3.51 ng/ml). 3D full-volume echocardiographic images were obtained and offline 2D as well as 3D speckle-tracking analysis of regional and global LV deformation was performed. All patients received CMR scans and myocarditis was diagnosed in 29 subjects based on original Lake-Louise criteria. The 16 patients, in whom myocarditis was excluded by CMR, served as controls. Regional changes in myocardial texture (diagnosed by CMR) were significantly associated with regional impairment of circumferential, longitudinal, and radial strain, as well as regional 3D displacement and total 3D strain. Interestingly, the 2D and 3D global longitudinal strain (GLS) showed higher diagnostic performance than well-known parameters associated with myocarditis, such as LVEF (as obtained by echocardiography and CMR) and LVEDV (as obtained by CMR). Conclusions: In this study, we examined the use of 3D-speckle-tracking echocardiography in patients with acute myocarditis. Global longitudinal strain was significantly impaired in patients with acute myocarditis and correlated with CMR findings. Therefore, 3D echocardiography could become a useful diagnostic tool in the primary diagnosis of myocarditis.

3D speckle tracking echocardiographic strain pattern in Hypertrophic Cardiomyopathy and its relation with Sudden Cardiac Death risk markers.

CONTEXT: Sudden cardiac death (SCD) predictability for assessing the need for primary insertion of Implantable Cardioverter Defibrillator (ICD) in patients with Hypertrophic cardiomyopathy (HCM) is difficult though there are several conventional risk markers. The role of deformation indices in predicting SCD in HCM is less addressed. OBJECTIVES: To analyse the 3D speckle tracking echocardiographic strain parameters of HCM patients and its relation with SCD risk markers. DESIGN AND STUDY METHODOLOGY: It was a cross-sectional observation study done over a period of one year with a follow up period of one year. Fifty HCM patients were included after screening eighty-two patients. Their global LV strain parameters, Global Longitudinal Strain (GLS), Global Circumferential Strain (GCS), Global Radial Strain (GRS) and Global area strain (GAS) were analysed with respect to their age and gender-matched controls. The various strain parameters were correlated with the conventional SCD risk markers and the ESC SCD risk score among these HCM patients. RESULTS: All the global strain parameters were significantly low in HCM patients compared to their controls {GLS -7.30 ± 3.424 vs -18.78 ± 2.342, p < 001; GCS -11.26 ± 2.754 vs -25.08 ± 3.542, p < 001; GRS 20.56 ± 8.929 vs 39.70 ± 7.546, p < 001}. On subgroup analysis of HCM patients with LV thickness >30 mm, abnormal exercise test, family history of SCD, LVOT gradients >30mmHgand more than one SCD risk marker had significantly low values for all global deformation parameters, when compared with their control HCM cohort. The ESC risk score also had significant inverse correlation with all deformation parameters (GLS 0.496, p < 0.001; GCS 0.491, p < 0.001; GRS -0.529, p < 0.001; GAS 0.519, p < 0.001). On follow up, only one event was recorded in this cohort. CONCLUSION: There exists a possible linear correlation between conventional SCD risk markers and 3D deformation parameters, which may be utilized for risk stratification and SCD predictability in HCM patients after confirmation with further large prospective studies.