Left ventricular twist mechanics in hypertrophic cardiomyopathy assessed by three-dimensional speckle tracking echocardiography

Multimodality Imaging in Sarcomeric Hypertrophic Cardiomyopathy: Get It Right…on Time

Hypertrophic cardiomyopathy (HCM) follows highly variable paradigms and disease-specific patterns of progression towards heart failure, arrhythmias and sudden cardiac death. Therefore, a generalized standard approach, shared with other cardiomyopathies, can be misleading in this setting. A multimodality imaging approach facilitates differential diagnosis of phenocopies and improves clinical and therapeutic management of the disease. However, only a profound knowledge of the progression patterns, including clinical features and imaging data, enables an appropriate use of all these resources in clinical practice. Combinations of various imaging tools and novel techniques of artificial intelligence have a potentially relevant role in diagnosis, clinical management and definition of prognosis. Nonetheless, several barriers persist such as unclear appropriate timing of imaging or universal standardization of measures and normal reference limits. This review provides an overview of the current knowledge on multimodality imaging and potentialities of novel tools, including artificial intelligence, in the management of patients with sarcomeric HCM, highlighting the importance of specific "red alerts" to understand the phenotype-genotype linkage.

Anabolic Steroids Use Is Associated with Impairments in Atrial and Ventricular Cardiac Structure and Performance in Athletes

PURPOSE

Despite potential severe cardiac side effects, anabolic androgenic steroids (AAS) are increasingly used by strength athletes. However, previous echocardiographic studies focused on the left ventricular (LV) strains but did not assess LV twist and untwist mechanics. Moreover, left atrial (LA) function has been often neglected, and its stiffness, an important determinant of LA reservoir function, has never been challenged. The aim of this study was to investigate the effects of AAS on LA and LV morphologies and functions in strength athletes.

METHODS

Fifty subjects including 20 strength-trained young athletes age 32.0 ± 8.5 yr with a mean duration of AAS use of 4.7 ± 1.8 yr (users), 15 athletes with no history of AAS use (nonusers) and 15 sedentary controls underwent speckle tracking echocardiography to assess LA and LV morphology and function.

RESULTS

Users showed higher LA reservoir dysfunction than nonusers (33.7% ± 10.9% vs 44.9% ± 9.9% respectively, P = 0.004) and higher LA stiffness (0.13 ± 0.05 vs 0.19 ± 0.08 A.U., respectively; P = 0.02), higher LV mass index and lower global and regional LV diastolic and systolic dysfunction (global longitudinal strain: -15.5% ± 3.2% vs -18.9% ± 1.8% respectively; P = 0.003), with a drop of LV twist-untwist mechanics (untwisting velocity: 61.5°·s-1 ± 20.2°·s-1 vs 73.7°·s-1 ± 16.1°·s-1 respectively, P = 0.04). There were significant correlations between LV mass and LV apical rotation (P = 0.003, r = 0.44) and diastolic longitudinal strain rate (P = 0.015, r = 0.33).

CONCLUSIONS

Our results showing significant LA and LV remodeling and dysfunctions in young AAS using athletes are alarming. Screening echocardiography based on speckle tracking echocardiography parameters for early diagnosis, as well as a stronger awareness in athletes and in physicians are warranted in this context.

Ventricular diastolic dimension over maximal myocardial thickness is robust landmark of systolic impairment in patients with hypertrophic cardiomyopathy

Background

The effects of focal hypertrophy on geometry of the left ventricle and systolic function have not been studied in patients with hypertrophic cardiomyopathy (HCM), despite the fact that the former is the most prominent disease characteristic. The aim of our study was to analyze systolic function over ventricle geometry, generating a functional index made from left ventricle end diastolic dimension (LVEDD) divided by end diastolic thickness of the region with maximal extent of hypertrophy and interventricular septum.

Material/Methods

Our hospital database of cardiac magnetic resonance was screened for HCM. Geometric functional index (GFI) was calculated for LVEDD over maximal end diastolic thickness (MaxEDT) giving GFI-M, while LVEDD over interventricular septum was expressed as GFI-I. There were 55 consecutive patients with HCM.

Results

There were 43 males (78.2%) and 12 females (21.8%). The mean age was 52.3±16.7 years (range: 15.5–76.4 years). A significant difference of GFI was found for preserved versus impaired systolic function of the left ventricle (preserved systolic function); GFI-M 2.28±0.60 versus 3.66±0.50 (p<0.001), and GFI-I 2.75±0.88 versus 3.81±0.87 (p<0.001), respectively. Diagnostic value was tested using receiver operating curve (ROC) analyzes, with GFI-M area under curve (AUC)=0.959 (95% CI: 0.868–0.994); (p<0.001) and GFI-I-AUC=0.847 (0.724–0.930); (p<0.001). GFI-M was superior to GFI-I for appraisal of left ventricle systolic dysfunction in HCM; ΔAUC=0.112 (0.018–0.207); (p=0.020).

Conclusions

GFI is a simple tool, with high sensitivity and specificity for detecting impairment of systolic function in patients with HCM. Further studies would be necessary to investigate its clinical and prognostic impacts, as well as reproducibility with prospective validation.

Three-dimensional speckle-tracking echocardiography: benefits and limitations of integrating myocardial mechanics with three-dimensional imaging

Three-dimensional (3D) speckle-tracking echocardiography (3DSTE) is an advanced imaging technique designed for left ventricular (LV) myocardial deformation analysis based on 3D data sets. 3DSTE has the potential to overcome some of the intrinsic limitations of two-dimensional STE (2DSTE) in the assessment of complex LV myocardial mechanics, offering additional deformation parameters (such as area strain) and a comprehensive quantitation of LV geometry and function from a single 3D acquisition. Albeit being a relatively young technique still undergoing technological developments, several experimental studies and clinical investigations have already demonstrated the reliability and feasibility of 3DSTE, as well as several advantages of 3DSTE over 2DSTE. This technique has provided new insights into LV mechanics in several clinical fields, such as the objective assessment of global and regional LV function in ischemic and non-ischemic heart diseases, the evaluation of LV mechanical dyssynchrony, as well as the detection of subclinical cardiac dysfunction in cardiovascular conditions at risk of progression to overt heart failure. However, 3DSTE generally requires patient's breathhold and regular rhythm for enabling an ECG-gated multi-beat 3D acquisition. In addition, the measurements, normal limits and cut-off values pertaining to 3D strain parameters are currently vendor-specific and highly dependent on the 3D ultrasound equipment used. Technological advances with improvement in spatial and temporal resolution and a standardized methodology for obtaining vendor-independent 3D strain measurements are expected in the future for a widespread application of 3DSTE in both clinical and research arenas. The purpose of this review is to summarize currently available data on 3DSTE methodology (feasibility, accuracy and reproducibility), strengths and weaknesses with respect to 2DSTE, as well as the main clinical applications and future research priorities of this emerging technology.

Left ventricular short-axis systolic function changes in patients with hypertrophic cardiomyopathy detected by two-dimensional speckle tracking imaging

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a genetic disease was characterised by left ventricular hypertrophy (LVH), myocardial fibrosis, fiber disarray. The short-axis systolic function is important in left ventricle function.

METHODS

Forty one healthy subjects and 37 HCM patients were enrolled for this research. Parasternal short-axis at the basal, middle, and apical levels were acquired by Echocardiography. The peak systolic circumferential strain of the endocardial, the middle and the epicardial layers, the peak systolic radial strain, and the peak systolic rotational degrees at different short-axis levels were measured by 2-dimensional speckle tracking imaging (2D-STI).

RESULTS

The peak systolic circumferential strain of the septum and anterior walls in HCM patients was significantly lower than normal subjects. All of the peak systolic radial strain in HCM patients was significantly lower than normal subjects. The rotational degrees at the base and middle short-axis levels in HCM patients were larger than normal subjects. The interventricular septal thickness in end-diastolic period correlated to the peak systolic circumferential strain of the septum wall.

CONCLUSIONS

The short-axis systolic function was impaired in HCM patients. The peak circumferential systolic strain of the different layers, peak systolic radial strain and rotation degrees of the different short-axis levels detected by 2D-STI are very feasible for assessing the short-axis function in HCM patients.

Left ventricular systolic function changes in hypertrophic cardiomyopathy patients detected by the strain of different myocardium layers and longitudinal rotation

BACKGROUND

Impairment of left ventricular (LV) longitudinal function has an important role in hypertrophic cardiomyopathy (HCM). This research investigated an association between the longitudinal strain of different myocardial layers, longitudinal rotation and the LV systolic function of HCM patients.

METHODS

The research was performed on 36 HCM patients and 36 healthy subjects. The peak systolic longitudinal strain of the subendocardial, midmyocardial, and subepicardial layers was measured using 2-dimensional speckle tracking echocardiography (2D-STE). The apical long-axis and 4- and 2- chamber views were acquired via 2D Doppler echocardiography. The curve of the longitudinal rotation was traced at 17 timepoints in the analysis of 2 cardiac cycles.

RESULTS

Compared with healthy subjects, in HCM patients regional LV peak systolic longitudinal strain was less, not only in hypertrophied LV myocardium, but also in non-hypertrophied myocardium. The rotational degrees of the midmyocardial-septal, apex, and lateral wall of HCM patients were significantly different from that of normal subjects, as follows. In HCM patients, clockwise longitudinal rotation was found. The interventricular septum thickness at end-diastole positively correlated with the peak longitudinal systolic strain of the subendocardial, the midmyocardial, and the subepicardial layers. The area under ROC curve values for subendocardial, midmyocardial and subepicardial layers in HCM patients were 0.923, 0.938, 0.948.

CONCLUSION

In HCM patients, the longitudinal function was damaged, even with normal LV ejection fraction. The peak longitudinal systolic strain of the subendocardial, midmyocardial, and subepicardial layers, and the longitudinal rotation detected by 2D-STE, are very sensitive predictors of systolic function in patients with HCM.

Echocardiographic evaluation of left ventricular diastolic function in cats: Hemodynamic determinants and pattern recognition

Left ventricular (LV) diastolic dysfunction is highly prevalent in cats and is a functional hallmark of feline cardiomyopathy. The majority of cats with hypertrophic, restrictive, and dilated cardiomyopathy have echocardiographic evidence of abnormal LV filling, even during the occult (preclinical) phase. Moderate and severe diastolic dysfunction is an indicator of advanced myocardial disease, is associated with clinical signs including exercise intolerance and congestive heart failure, affects outcome, and influences therapeutic decisions. Therefore, identification and quantification of LV diastolic dysfunction are clinically important. Surrogate measures of diastolic function determined by transthoracic two-dimensional, M-mode, and Doppler echocardiographic (DE) methods have been used widely for such purpose. Major functional characteristics of LV diastole, including global function, relaxation and untwist, chamber compliance, filling volume, and the resultant filling pressures can be semi-quantified by echocardiographic methods, and variables retrieved from transmitral flow, pulmonary vein flow, and tissue Doppler recordings are most frequently used. Although there is still a critical lack of well-designed studies in the field, knowledge has steadily accumulated over the past 20 years, reference ranges of diastolic echocardiographic variables have been determined, epidemiological studies have been conducted, and new treatments of diastolic dysfunction in cats have been evaluated. This report will give the reader a summary of the current status in the field of feline diastology with focus on the noninvasive diagnostic methods and interpretation of echocardiographic surrogate measures of LV diastolic function. Lastly, a grading system using a composite of left atrial size and various DE variables potentially useful in the functional classification of LV diastole in cats is introduced.

Left ventricular twist mechanics in the context of normal physiology and cardiovascular disease: a review of studies using speckle tracking echocardiography

The anatomy of the adult human left ventricle (LV) is the result of its complex interaction with its environment. From the fetal to the neonatal to the adult form, the human LV undergoes an anatomical transformation that finally results in the most complex of the four cardiac chambers. In its adult form, the human LV consists of two muscular helixes that surround the midventricular circumferential layer of muscle fibers. Contraction of these endocardial and epicardial helixes results in a twisting motion that is thought to minimize the transmural stress of the LV muscle. In the healthy myocardium, the LV twist response to stimuli that alter preload, afterload, or contractility has been described and is deemed relatively consistent and predictable. Conversely, the LV twist response in patient populations appears to be a little more variable and less predictable, yet it has revealed important insight into the effect of cardiovascular disease on LV mechanical function. This review discusses important methodological aspects of assessing LV twist and evaluates the LV twist responses to the main physiological and pathophysiological states. It is concluded that correct assessment of LV twist mechanics holds significant potential to advance our understanding of LV function in human health and cardiovascular disease.

Elevated Ca2+ transients and increased myofibrillar power generation cause cardiac hypercontractility in a model of Noonan syndrome with multiple lentigines

Noonan syndrome with multiple lentigines (NSML) is primarily caused by mutations in the nonreceptor protein tyrosine phosphatase SHP2 and associated with congenital heart disease in the form of pulmonary valve stenosis and hypertrophic cardiomyopathy (HCM). Our goal was to elucidate the cellular mechanisms underlying the development of HCM caused by the Q510E mutation in SHP2. NSML patients carrying this mutation suffer from a particularly severe form of HCM. Drawing parallels to other, more common forms of HCM, we hypothesized that altered Ca(2+) homeostasis and/or sarcomeric mechanical properties play key roles in the pathomechanism. We used transgenic mice with cardiomyocyte-specific expression of Q510E-SHP2 starting before birth. Mice develop neonatal onset HCM with increased ejection fraction and fractional shortening at 4-6 wk of age. To assess Ca(2+) handling, isolated cardiomyocytes were loaded with fluo-4. Q510E-SHP2 expression increased Ca(2+) transient amplitudes during excitation-contraction coupling and increased sarcoplasmic reticulum Ca(2+) content concurrent with increased expression of sarco(endo)plasmic reticulum Ca(2+)-ATPase. In skinned cardiomyocyte preparations from Q510E-SHP2 mice, force-velocity relationships and power-load curves were shifted upward. The peak power-generating capacity was increased approximately twofold. Transmission electron microscopy revealed that the relative intracellular area occupied by sarcomeres was increased in Q510E-SHP2 cardiomyocytes. Triton X-100-based myofiber purification showed that Q510E-SHP2 increased the amount of sarcomeric proteins assembled into myofibers. In summary, Q510E-SHP2 expression leads to enhanced contractile performance early in disease progression by augmenting intracellular Ca(2+) cycling and increasing the number of power-generating sarcomeres. This gives important new insights into the cellular pathomechanisms of Q510E-SHP2-associated HCM.

Normal left ventricular torsion mechanics in healthy children: age related changes of torsion parameters are closely related to changes in heart rate

Background and Objectives

This study was aimed at assessing left ventricular torsion (LVtor) mechanics using speckle tracking echocardiography (STE), establishing normal reference values of principal LVtor parameters, and analyzing the age-related changes in normal children.

Subjects and Methods

Eighty children (aged 3 months to 15 years) with normal cardiac function and rhythm were recruited. LVtor parameters including rotations, twist and untwist, torsion, and their rate indices were measured using STE. Age and heart rate related changes of the parameters were analyzed.

Results

Speckle tracking echocardiography analyses for LVtor parameters had excellent reliability in 64 of 80 subjects (80%) (intraclass correlation coefficients; 0.93-0.97). Early systolic twist (EST) motions (-8.4--0.1°) were observed in all subjects during an early 20±7% of systolic time intervals. The peak systolic twist and torsion were 17.0±6.5° and 2.9±1.3°/cm, respectively. The peak twist velocity was recorded at 51±13% of systolic time and the peak untwist velocity at 13.8±11.5% of diastolic time intervals. Multivariate analysis showed that heart rate change was an independent predictor of changes in torsion parameters; significantly decreasing LV length-normalized apical and basal rotation, torsion, and twist and untwist rate with increasing age. Isovolumetric recoil rate was independent of change in age and heart rate.

Conclusion

Left ventricle showed unique torsion mechanics in children with EST, torsion, and untwists. Heart rate was an independent predictor of the change in torsion parameters with aging.

Four-Dimensional Speckle Tracking Echocardiography in Patients with Hypertrophic Cardiomyopathy

OBJECTIVE

Abnormal left ventricular (LV) deformational mechanics have been demonstrated in patients with hypertrophic cardiomyopathy (HCM) using two-dimensional (2D) speckle tracking echocardiography, but there is not enough information about the four-dimensional speckle tracking echocardiography (4DSTE) in these patients. The objective of the study was to identify and quantify the left ventricular contractility in patients with HCM using 4DSTE.

METHODS

Thirty patients [age, 54.6 ± 12.1 years; 12 (40%) women] with diagnosis of nonobstructive HCM and 20 healthy controls [age, 47.42 ± 11.43 years; 8 (40%) women] underwent 4DSTE measurement of longitudinal, radial, circumferential, and area strains.

RESULTS

Patients with HCM showed lower longitudinal (-13.5% vs. -20.3%, P < 0.001) and radial (33.4% vs. 43.6%, P < 0.001) strain, but higher circumferential (-22.7% vs. -15.9%, P < 0.001) and area (-30.7% vs. -22.1%, P < 0.001) strain than control subjects. Peak LV twist showed significantly higher values in patients with HCM (13.7 ± 5.3 vs. 11.3 ± 4.8, P < 0.005).

CONCLUSIONS

Patients with HCM have reduced longitudinal and radial strain but increased circumferential and area strain on 4DSTE. These results are found appropriate with previous 2DSTE studies. Thus, 4DSTE is useful to determine LV deformational mechanics.

Left ventricular rotational mechanics in Tanzanian children with sickle cell disease

Background

Sickle cell disease (SCD) is a common inherited hemoglobinopathy. Adults with SCD manifest both systolic and diastolic cardiac dysfunction, though the age of onset of dysfunction has not been defined. Left ventricular (LV) rotational mechanics have not been studied in children with SCD. The aim of this study was to investigate whether cardiac rotational mechanics differed between children with SCD and age-matched controls.

Methods

Basal and apical LV short-axis images were acquired prospectively in 213 patients with SCD (mean age, 14.1 ± 2.6 years) and 49 controls (mean age, 13.3 ± 2.8 years) from the Muhimbili Sickle Cohort in Dar es Salaam, Tanzania. The magnitude of basal and apical rotation, net twist angle, torsion, and untwist rate were obtained by two-dimensional speckle-tracking. The timing of events was normalized to aortic valve closure.

Results

Mean basal rotation was significantly lower in patients with SCD compared with controls (P = .012), although no difference was observed in apical rotation (P = .37). No statistically significant differences in torsion or net twist angle were detected. Rotation rate at the apex (P = .001) and base (P = .0004) were significantly slower in subjects with SCD compared with controls. Mean peak untwisting rate was also significantly slower in patients with SCD (P = .006). No associations were found between hemoglobin concentration and apical rotation, basal rotation, net twist, and torsion.

Conclusion

This study demonstrates alterations in LV rotational mechanics in children with SCD, including lower basal rotation, peak differential twist, and untwist rate. These abnormalities denote subclinical changes in LV systolic and diastolic performance in children with SCD. Future work may reveal an association between rotational metrics and long-term patient outcomes.

Assessment of left ventricular twist mechanics by speckle tracking echocardiography reveals association between LV twist and myocardial fibrosis in patients with hypertrophic cardiomyopathy

We aimed to investigate whether left ventricular (LV) twist analysis can detect the extent of myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM). This prospective case–control study recruited 81 consecutive patients with HCM examined between January 2012 and April 2013. Data of 76 patients were analyzed after excluding 5 patients whose echocardiographic images were of poor quality. Healthy volunteers (n = 46) served as controls. Both groups underwent comprehensive echocardiographic examination (i.e., Bas-Rotation, AP-Rotation, LVEF, LADs, IVST, LAVi, E/Em, LVMI, advanced LV-twist analysis by speckle tracking echocardiography) and magnetic resonance imaging. Between-group differences were analyzed by independent t test; logistic regression analysis was performed to identify effect factors. No significant differences were found between baseline characteristics of HCM and control groups (all p > 0.05). HCM patients had significantly higher Bas-Rotation, AP-Rotation, LV Twist, LVEF, LADs, IVST, LAVi, E/Em and LVMI than controls (all p < 0.0001) and significantly lower LVDd and E/A (both p < 0.001). Bas-Rotation, AP-Rotation, LV-Twist, LADs, IVST, LAVi, E/Em and LVMI were significantly higher in HCM patients with fibrosis than in those without fibrosis (p < 0.001), but no significant differences in other echocardiographic parameters were found between those with and without fibrosis. Age, Bas-Rotation, AP-Rotation, LV twist, LADs, IVST, LAVi, E/A, E/Em, and LVMI were significant effect factors for fibrosis. AUROC analysis showed that LV twist had high discriminatory power to detect extent of myocardial fibrosis (AUC 0.996, 95 % CI 0.989–1.004, p < 0.001). Left ventricular twist mechanics are associated with the extent of myocardial fibrosis. LV-twist assessment by STE may be clinically useful.

Ventricular structure-function relations in health and disease: part II. Clinical considerations

Normal cardiac function of the left and right ventricles, together with the septum, is related to form/function interactions within the helical ventricular myocardial band. This knowledge is a prerequisite to understanding form/function interactions in diseases and for planning new treatments. Topics discussed include congestive heart failure in dilated hearts of ischaemic, valvar or nonischaemic origin as well as diastolic dysfunction. Similar thinking underlies novel treatments for dyssynchrony in pacing, together with focusing upon varying global left or right ventricular anatomy to correct mitral and tricuspid insufficiency caused by tethering of the leaflets. The septum is the lion of the right ventricle and insight is provided into offsetting septal damage during cardiac surgery, rebuilding its anatomical structure in post-tetralogy pulmonary insufficiency, as well as rectifying its dysfunction by decompression in patients with a left ventricular assist device.

Disease-specific differences of left ventricular rotational mechanics between cardiac amyloidosis and hypertrophic cardiomyopathy

Left ventricular (LV) twist (LVT) and untwisting (LVUT) rate are global and thorough parameters of LV function. The aim of the present study was to investigate the differences in LV rotational mechanics between patients with cardiac amyloidosis (CA) and hypertrophic cardiomyopathy (HCM). Twenty consecutive patients with CA, 20 consecutive patients with HCM, and 20 consecutive subjects without evidence of structural heart disease were included. Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) imaging was performed to evaluate biventricular function, LV mass index, and presence/extent of LGE. Feature-tracking analysis was applied to LV basal and apical short-axis images to determine peak LVT, time to peak LVT, peak LVUT rate, and time to peak LVUT rate. Peak LVT and peak LVUT rate were significantly impaired in patients with CA compared with controls (P < 0.05 for both). In patients with HCM, peak LVT was increased (P < 0.05) compared with controls, whereas peak LVUT rate was preserved (P > 0.05). Time to peak LVUT rate was significantly prolonged in patients with CA and in patients with HCM compared with controls (ANOVA P < 0.001). At multivariate analysis, age (P = 0.007), LV ejection fraction (P = 0.035) and extent of LGE (P < 0.001) were independently related to peak LVT, and LV mass index (P = 0.015) and extent of LGE (P = 0.004) were independently related to peak LVUT rate, whereas extent of LGE (P < 0.001) was the only variable independently related to time to peak LVUT rate. In conclusion, CA and HCM have specific behavior of LV rotational mechanics. The extent of LGE significantly influences the LV rotational mechanics.

Estimating the Myocardium's Angle of Three-Dimensional Trajectory, Using the Tracking of Sequential Two-Dimensional Echocardiography Images

BACKGROUND

In this study, the angle of the myocardium's trajectory in three dimensions (ф) was estimated by simultaneous use of long-axis and short-axis views of left ventricle septum two-dimensional images. Then correlation of three-dimensional trajectory's angle with the rotation angle from the long (χ) and short (θ) axis views was estimated and compared at the three levels of base, mid and apex of the interventricular septum wall.

METHODS

Two-dimensional echocardiography images of long- and short-axis views of 19 healthy men were recorded and analyzed. Using an electrocardiogram of each individual, the images of the two views were synchronized. The interventricular septum wall motion at the three levels of base, mid and apex were estimated, using a block matching algorithm throughout three cardiac cycles. Considering the defined system of coordinates and the position vectors in long and short-axis views, the 3-dimensional angle of the trajectory was calculated.

RESULTS

Maxima of the ф, θ, and χ angles were extracted at 16.33 ± 3.01, 10.61 ± 3.38, and 15.11 ± 3.30 degrees at base level, 22.77 ± 4.95, 7.78 ± 2.96, and 16.72 ± 2.66 degrees at mid level and 14.60 ± 5.81, 10.37 ± 5.48, and 8.79 ± 3.32 degrees at apex level, respectively, of the septum wall, respectively. This study shows significant correlation between the angle of 3-dimensional trajectory (ф) with the angle in short axis view (θ) of the septum wall at the apex level; and also with the angle in long axis view (χ) of the septum wall at base and mid levels.

CONCLUSION

Due to the motion of the wall of the left ventricle in three dimensions, and the non-isotropic structure of myofibers, the angle of 3-dimensional trajectory was estimated using the speckle tracking method of 2-dimentional echocardiography images.

Left ventricular strain reduction is not confined to the noncompacted segments in noncompaction cardiomyopathy-insights from the three-dimensional speckle tracking echocardiographic MAGYAR-path study

INTRODUCTION

Noncompaction cardiomyopathy (NCCM) is a new clinical entity characterized by prominent trabecular meshwork and deep intertrabecular recesses communicating with the left ventricular (LV) cavity due to arrest of the normal embryogenesis of the endomyocardium. The aim of the present study was to evaluate different contributions of noncompacted and compacted LV segments to the global LV dysfunction by three-dimensional (3D) speckle tracking echocardiography (3DSTE)-derived strain parameters in NCCM.

PATIENTS AND METHODS

The present study comprised 9 patients with typical features of NCCM. Due to the limited image quality, one patient was excluded from the evaluations. Finally, 128 segments of 8 NCCM patients were assessed. Their results were compared to 176 segments of 11 healthy volunteers. Complete two-dimensional Doppler echocardiography extended with 3DSTE has been performed in all cases.

RESULTS

Fifty-five of 128 LV segments (43%) proved to be noncompacted in NCCM patients. All strain parameters of segments of NCCM patients were significantly lower as compared to segments of controls. Only radial strain (6.99 ± 7.36% vs. 12.58 ± 12.78% vs. 25.24 ± 11.76%, P < 0.001 and P < 0.05, respectively) and 3D strain (7.79 ± 7.59% vs. 14.67 ± 14.04% vs. 27.78 ± 12.57%, P < 0.001 and P < 0.05, respectively) showed further reduction in noncompacted segments as compared to compacted segments.

CONCLUSIONS

Left ventricular strain reduction is not confined to the nocompacted segments in NCCM. Radial and 3D strain parameters show further reduction in noncompacted segments compared to compacted segments.

Deformation patterns in genotyped patients with hypertrophic cardiomyopathy

AIMS

Echocardiographic strain imaging with two-dimensional speckle tracking is an emerging tool for defining cardiac function and identifying preclinical hypertrophic cardiomyopathy (HCM). In HCM, a reverse septal contour is a strong predictor of mutation positive sarcomeric HCM. The objective of this study was to determine whether left ventricular (LV) deformation patterns can differentiate between genotype positive and negative patients within a large HCM cohort.

METHODS AND RESULTS

One hundred and thirty one patients (89 males, age 55 ± 15 years) with clinically diagnosed HCM underwent comprehensive transthoracic echocardiography inclusive of LV strain imaging, LV dimensions and ejection fraction, septal contour and thickness, and identification of obstructive physiology. Longitudinal peak systolic strain was assessed from 17 LV myocardial segments blinded to the patient's genetic test results derived from comprehensive genotyping of nine myofilament HCM-associated genes. Genotyping revealed that 51 of 131 patients (39%) were mutation positive for sarcomeric/myofilament-HCM (genotype positive). Regional strain was lower in genotype-positive patients in mid inferoseptal (P = 0.004), basal anteroseptal (P = 0.04), and basal inferoseptal segments (P = 0.002) compared with HCM patients lacking a mutation (genotype negative). Strain patterns in reverse-curve, genotype-positive HCM differed significantly from genotype negative, sigmoidal HCM in multiple segments. However, when comparing genotype-negative and genotype-positive patients with the same septal morphology, there were no significant regional strain differences. Septal thickness positively correlated with global and basal anteroseptal longitudinal strain (r = 0.34 and r = 0.54, respectively, P < 0.0001).

CONCLUSION

Significant regional strain differences in genotyped HCM patients are dependent upon septal morphology or thickness, not genotype. Phenotypic expression of deformation patterns appears heterogeneous.

Quantification of changes in septal strain after alcohol septal ablation in hypertrophic obstructive cardiomyopathy-cases from the three-dimensional speckle tracking echocardiographic MAGYAR-path study

Patients with hypertrophic obstructive cardiomyopathy undergoing alcohol septal ablation are presented. Three-dimensional speckle tracking echocardiography (3DSTE) is a new, noninvasive tool for quantification of myocardial deformation. In both cases, 3DSTE was performed 1 day before and 3 days after alcohol septal ablation to quantify changes in septal strain of ablated area. Results could suggest the possible role of 3DSTE in the quantitative evaluation of the success of alcohol septal ablation.

New three-dimensional speckle-tracking echocardiography identifies global impairment of left ventricular mechanics with a high sensitivity in childhood cancer survivors

BACKGROUND

The aim of this case-control study was to assess the usefulness of three-dimensional (3D) speckle-tracking echocardiography in the evaluation of global left ventricular (LV) myocardial performance in adolescent and adult survivors of childhood cancers.

METHODS

Fifty-three anthracycline-treated survivors of childhood cancers (mean age, 18.6 ± 5.1 years) and 38 controls were studied. Three-dimensional speckle-tracking echocardiography was performed to assess LV 3D global and segmental strain, time to peak segmental 3D strain, LV torsion, and ejection fraction. LV systolic dyssynchrony index (SDI) was calculated as the percentage of the standard deviation of times to peak strain of the 16 segments divided by the RR interval. A global performance index (GPI) was calculated as (global 3D strain × torsion)/SDI. The area under the receiver operating characteristic curve was calculated to determine the capability of various echocardiographic indices to discriminate between patients and controls.

RESULTS

Compared with controls, patients had significantly reduced LV global 3D strain (P < .001), torsion (P < .001), and GPI (P < .001) and greater SDI (P < .001). All except the basal anteroseptal segment in patients had reduced regional 3D strain compared with controls (P < .05 for all). Global 3D strain (P = .018), SDI (P = .003), and GPI (P = .02) were correlated with cumulative anthracycline dose. The areas under the curves for GPI, global 3D strain, 1/SDI, torsion, and ejection fraction were 0.92, 0.79, 0.79, 0.79, and 0.78, respectively. A GPI cutoff of 10.6°/cm had sensitivity of 84.9% and specificity of 81.6% of differentiating patients from controls.

CONCLUSIONS

Three-dimensional speckle-tracking echocardiography enables the derivation of an index of LV global performance that incorporates LV 3D strain, dyssynchrony, and torsion for the sensitive detection of altered LV mechanics in childhood cancer survivors.

Correlations between echocardiographic aortic elastic properties and left ventricular rotation and twist--insights from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study

INTRODUCTION

There is an interaction between the left ventricle (LV) and the vascular system, which plays a crucial role in determining cardiac output. LV twist could be evaluated by three-dimensional speckle-tracking echocardiography (3DSTE) as the net difference of counterclockwise apical and clockwise basal LV rotations during systole. Aortic elasticity parameters could be measured during a routine transthoracic echocardiographic examination. The current study was designed to evaluate correlations between echocardiographic aortic elastic properties and LV rotational mechanics in healthy subjects.

METHODS

The present study comprised 26 healthy volunteers (mean age: 34.5 ± 9.8 years, 13 men). The following aortic elastic properties were measured from aortic data and forearm blood pressure values: aortic strain, distensibility and stiffness index (ASI). 3DSTE was used to measure basal and apical LV rotations and LV twist.

RESULTS

During 3DSTE, basal LV rotation proved to be -2.42 ± 1.43 degree, while apical LV rotation was 8.56 ± 1.43 degree, therefore LV twist was 11.01 ± 5.19 degree. Aortic strain (0.131 ± 0.094), distensibility (3.61 ± 2.54 cm² dynes(-1) 10(-6)) and ASI (4.08 ± 0.79) were also calculated. Apical LV rotation correlated with aortic distensibility (r = -0.36, P<0.05) and ASI (r = 0.41, P<0.05). LV twist showed similar correlation with ASI (r = 0.42, P<0.05).

DISCUSSION

Correlations exist between echocardiographic aortic elastic properties and 3DSTE-derived LV rotation and twist in healthy subjects.

Determinants and clinical significance of flow via the fenestration in the Fontan pathway: a multimodality study

BACKGROUND

The use of a fenestration in the Fontan pathway remains controversial, partly because its hemodynamic effects and clinical consequences are insufficiently understood. The objective of this study was to quantify the magnitude of fenestration flow and to characterize its hemodynamic consequences after an intermediate interval after surgery.

METHODS

Twenty three patients with a fenestrated extracardiac conduit prospectively underwent investigation by cardiac magnetic resonance (CMR), echocardiography, and invasive manometry under the same general anesthetic 12 ± 4 months after Fontan surgery. Fenestration flow was determined using phase contrast CMR by subtracting flow in the Fontan pathway above the fenestration from Fontan flow below the fenestration.

RESULTS

Fenestration flow constituted a mean of 31 ± 12% (range 8-50%) of ventricular preload. It was associated with a lower Qp/Qs (r = -0.64, p=0.001) and oxygen saturation (r = -0.74, p<0.0001). Fenestration flow volume was correlated with pulmonary vascular resistance (r = 0.45, p = 0.04) and markers of ventricular diastolic function (early diastolic strain rate r = 0.57, p = 0.008 and ventricular untwist rate r = 0.54, p = 0.02). In 14 patients (61%) all of the net inferior vena cava flow and part of the superior vena cava flow were diverted into the systemic atrium and did not reach the lungs.

CONCLUSIONS

Fenestration flow can be measured accurately with CMR. In two-thirds of the patients not only all of the inferior vena cava flow, but also some of the superior vena cava flow is diverted through the fenestration. Fenestration flow is driven by a balance between pulmonary vascular resistance and early diastolic ventricular function.

Three-dimensional speckle-tracking echocardiography – a further step in the non-invasive three-dimensional cardiac imaging

Three-dimensional speckle-tracking echocardiography is a new cardiac imaging methodology, which allows three-dimensional non-invasive evaluation of the myocardial mechanics. The aim of this review is to present this new tool emphasizing its diagnostic potentials and demonstrating its limitations, as well. Orv. Hetil., 2012, 153, 1570–1577.

The role of 3D wall motion tracking in heart failure

Heart failure is a major health problem in developed countries and a growing one in developing countries. Cardiac remodeling in heart failure affects myocardial mechanics, which requires comprehensive evaluation in three dimensions. The novel technique of 3D wall motion tracking applies speckle tracking technology to full volume, 3D echocardiographic datasets. Quantification of conventional and novel left ventricular (LV) parameters including volumes, ejection fraction, global and regional 3D strain, endocardial area strain, twist, and dyssynchrony, and identification of the site of latest mechanical activation are feasible on the basis of a single acquisition of a full-volume dataset. Clinical applications of 3D wall motion tracking include the assessment of global and regional LV performance in ischemic and nonischemic heart diseases, evaluation of mechanics in cardiomyopathies and congenital heart disease, potential selection of patients for cardiac resynchronization therapy and prediction of their response, and detection of subclinical cardiac dysfunction in diseases with likelihood of progression to heart failure. Technological advances with improvement in spatial and temporal resolution of this novel imaging modality are expected. Although 3D wall motion tracking is still in its infancy, this method has begun to provide new insights into LV mechanics and has already found clinical applications. Future developments in 3D assessment of right ventricular and myocardial layer-specific mechanics are awaited.

Three-dimensional speckle-tracking echocardiography: methodological aspects and clinical potential

Speckle-tracking echocardiography (STE) is an advanced echocardiographic technique that allows a novel approach to the assessment of cardiac physiology through the study of myocardial mechanics. In its three-dimensional (3D) modality, it overcomes the drawbacks inherent to other echocardiographic techniques, namely two-dimensional echocardiography and tissue Doppler imaging. Several research studies and software improvements have led 3D-STE to become a promising tool for accurate evaluation of global and regional cardiac function. This article addresses the image acquisition, analytical methods, and parameters of myocardial mechanics that could be derived from 3D-STE. This systematic guidance may help to establish its usefulness in the global and regional evaluation of cardiac function, and to facilitate its clinical application.