Left ventricular rotation and twist: why should we learn?

Speckle tracking echocardiography in a patient with viral myocarditis and acute myocardial infarction

The present case of a patient with acute myocarditis with preserved left ventricular (LV) ejection fraction at the acute stage illustrates the obvious impairment of circumferential and rotational deformation, which can be documented by speckle tracking echocardiography. Thus, qualitative patterns of LV twist, radial strain, and circumferential layer strain, might be a new approach to detect acute myocarditis. The early diagnosis of acute myocarditis by echocardiography is important because of the considerable risk of cardiovascular morbidity as documented by the occurrence of an acute myocardial infarction presumably induced by inflammatory process in this case. <Learning objective: The compound of myocardial deformations caused by left ventricular subendomyocardial and subepimyocardial fibers may be a crucial diagnostic target in cardiac diseases. The predominant involvement of viral myocarditis of the outer myocardial layers might induce impairment of circumferential and rotational deformation, which can potentially serve as a new diagnostic key by echocardiography. In contrast, left ventricular ejection fraction and longitudinal deformation are often observed within normal ranges in patients with acute myocarditis. Acute myocardial infarction as a major cardiac event in acute stage of myocarditis causes completely different deformation patterns, mainly by the predominant involvement of the inner myocardial layers inducing severe pathologies of territorial longitudinal deformation. Patients with suspected acute myocarditis and abnormal findings of circumferential and rotational deformation should undergo additional diagnostic procedures as cardiac magnetic resonance and myocardial biopsy to confirm the diagnosis.>.

Left ventricular apical rotation is associated with mitral annular function in healthy subjects. Results from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study

Introduction

Left ventricular (LV) twist is considered an essential part of LV function due to oppositely directed LV basal and apical rotations. Several factors could play a role in determining LV rotational mechanics in normal circumstances. This study aimed to investigate the relationship between LV rotational mechanics and mitral annular (MA) size and function in healthy subjects.

Methods

The study comprised 118 healthy adult volunteers (mean age: 31.5 ± 11.8 years, 50 males). All subjects had undergone complete two-dimensional (2D) Doppler echocardiography and three-dimensional speckle-tracking echocardiography (3DSTE) at the same time by the same echocardiography equipment.

Results

The normal mean LV apical and basal rotations proved to be 9.57 ± 3.33 and -3.75 ± 1.98°, respectively. LV apical rotation correlated with end-systolic MA diameter, area, perimeter, fractional area change, and fractional shortening, but did not correlate with any end-diastolic mitral annular morphologic parameters. The logistic regression model identified MA fractional area change as an independent predictor of ≤6° left ventricular apical rotation (P < 0.003).

Conclusions

Correlations could be detected between apical LV rotation and end-systolic MA size and function, suggesting relationships between MA dimensions and function and LV rotational mechanics.

Left ventricular rotational deformation changes by speckle tracking imaging before and 24 hours after transcatheter closure of large secundum atrial septal defects in children

BACKGROUND

Large atrial septal defects (ASDs) in children cause increased volume overload of the right side of the heart which in turn lead to impairment of left ventricular (LV) performance.

AIM

The aim of this study was to evaluate immediate LV rotational deformation changes in children with large ASDs post-device closure and removal of right ventricle (RV) volume overload.

PATIENTS AND METHODS

Twenty children who underwent transcatheter closure (TCC) of large secundum ASDs were included in the study. LV rotational deformation was assessed pre- and 24 hours post-device closure using speckle tracking imaging (STI).

RESULTS

55% were females with mean age 6.1 ± 3.5 years. LV peak basal clockwise rotation improved significantly (-6.9 ± 2.6° before vs -10.3 ± 4.1° after TCC, P = .005), and time to peak clockwise rotation (345.1 ± 124.7 milliseconds (ms) before vs 282.2 ± 82.9 ms after closure, P = .02). There was no significant difference in apical rotational parameters including peak counterclockwise rotation (P > .05 for both). LV twist (11.3 ± 3.8° before vs 17.5 ± 7.1° after closure, P = .001) and torsion (2.1 ± 0.7°/cm before vs 3.1 ± 1.2°/cm after closure, P = .01) were significantly improved, mainly as the result of improvement of LV basal rotation. LV revealed a significant increase in LV end-diastolic volumes (P = .02) 24 hour after TCC with no significant change (P > .05) in end-systolic volumes after closure.

CONCLUSION

Increased peak LV twisting and torsion were attributed to the improved peak systolic clockwise basal rotation after TCC of large ASDs in children.

How His bundle pacing prevents and reverses heart failure induced by right ventricular pacing

Ideal heart performance demands vigorous systolic contractions and rapid diastolic relaxation. These sequential events are precisely timed and interdependent and require the rapid synchronous electrical stimulation provided by the His-Purkinje system. Right ventricular (RV) pacing creates slow asynchronous electrical stimulation that disrupts the timing of the cardiac cycle and results in left ventricular (LV) mechanical asynchrony. Long-term mechanical asynchrony produces LV dysfunction, remodeling, and clinical heart failure. His bundle pacing preserves synchronous electrical and mechanical LV function, prevents or reverses RV pacemaker-induced remodeling, and reduces heart failure.

Left ventricular rotational mechanics in hypereosinophilic syndrome-Analysis from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study

INTRODUCTION

Hypereosinophilic syndrome (HES) is a very heterogeneous group of disorders with varied etiologies characterized by peripheral eosinophilia and eosinophilic tissue/end-organ damage. Three-dimensional speckle-tracking echocardiography (3DSTE) was used for assessment of left ventricular (LV) rotational mechanics in HES patients.

METHODS

The study comprised 13 HES patients, from which one patient was excluded due to insufficient image quality. The remaining patient population consisted of 12 HES cases (mean age: 59.7 ± 13.7 years, eight males). The control group consisted of 36 healthy volunteers (mean age: 52.9 ± 8.3 years, 23 males). 3DSTE was used for the evaluation of LV rotational abnormalities.

RESULTS

Both LV apical rotation (4.86 ± 1.92 degree vs 10.07 ± 3.92 degree, P < .0001) and LV twist (8.52 ± 2.79 degree vs 14.41 ± 4.26 degree, P < .0001) showed significant deteriorations in most of HES patients. Time-to-peak LV apical rotation (380 ± 115 ms vs 344 ± 69 ms, P = .56), LV basal rotation (335 ± 148 ms vs 337 ± 111 ms, P = .89), and LV twist (348 ± 91 ms vs 320 ± 60 ms, P = .64) were not significantly different between HES patients and controls. No correlations could be detected between absolute eosinophil count and eosinophil ratio and apical LV rotation (r = 0.12, P = .51 and r = 0.23, P = .45, respectively) and LV twist (r = 0.24, P = .39 and r = 0.31, P = .34, respectively). In two subjects, the absence of LV twist called LV "rigid body rotation" (RBR) was detected.

CONCLUSIONS

Reduced LV apical rotation and twist could be demonstrated in HES. LV-RBR could be detected in some HES patients.

Torsional motion of the left ventricle does not affect ventricular fluid dynamics of both foetal and adult hearts

Left ventricular torsion is caused by shortening and relaxation of the helical fibres in the myocardium, and is thought to be an optimal configuration for minimizing myocardial tissue strains. Characteristics of torsional motion has also been proposed to be markers for cardiac dysfunction. However, its effects on fluid and energy dynamics in the left ventricle have not been comprehensively investigated. To investigate this, we performed image-based flow simulations on five healthy adult porcine and two healthy human foetal left ventricles (representing two different length scales) at different degrees of torsional motions. In the adult porcine ventricles, cardiac features such as papillary muscles and mitral valves, and cardiac conditions such as myocardial infarctions, were also included to investigate the effect of twist. The results showed that, for all conditions investigated, ventricular torsional motion caused minimal changes to flow patterns, and consistently accounted for less than 2% of the energy losses, wall shear stresses, and ejection momentum energy. In contrast, physiological characteristics such as chamber size, stroke volume and heart rate had a much greater influence on flow patterns and energy dynamics. The results thus suggested that it might not be necessary to model the torsional motion to study the flow and energy dynamics in left ventricles.

Sex-related Left Ventricle Rotational and Torsional Mechanics by Block Matching Algorithm

Background:

The aim of the present study was to evaluate how left ventricular twist and torsion are associated with sex between sex groups of the same age.

Materials and Methods:

In this analytical study, twenty one healthy subjects were scanned in left ventricle basal and apical short axis views to run the block matching algorithm; instantaneous changes in the base and apex rotation angels were estimated by this algorithm and then instantaneous changes of the twist and torsion were calculated over the cardiac cycle.

Results:

The rotation amount between the consecutive frames in basal and apical levels was extracted from short axis views by tracking the speckle pattern of images. The maximum basal rotation angle for men and women were -6.94°±1.84 and 9.85°±2.36 degrees (p-value = 0.054), respectively. Apex maximum rotation for men was -8.89°±2.04 and for women was 12.18°±2.33 (p-value < 0.05). The peak of twist angle for men and women was 16.78 ± 1.83 and 20.95± 2.09 degrees (p-value < 0.05), respectively. In men and women groups, the peak of calculated torsion angle was 5.49°±1.04 and 7.12± 1.38 degrees (p-value < 0.05), respectively.

Conclusion:

The conclusion is that although torsion is an efficient parameter for left ventricle function assessment, because it can take in account the heart diameter and length, statistic evaluation of the results shows that among men and women LV mechanical parameters are significantly different. This study was mainly ascribed to the dependency of the torsion and twist on patient sex.

Finite Element Driven Design Domain Identification of a Beating Left Ventricular Simulator

Almost ten percent of the American population have heart diseases. Since the number of available heart donors is not promising, left ventricular assist devices are implemented as bridge therapies. Development of the assist devices benefits from both in-vivo animal and in-vitro mock circulation studies. Representation of the heart is a crucial part of the mock circulation setups. Recently, a beating left ventricular simulator with latex rubber and helically oriented McKibben actuators has been proposed. The simulator was able to mimic heart wall motion, however, flow rate was reported to be limited to 2 liters per minute. This study offers a finite element driven design domain identification to identify the combination of wall thickness, number of actuators, and the orientation angle that results in better deformation. A nonlinear finite element model of the simulator was developed and validated. Design domain was constructed with 150 finite element models, each with varying wall thickness and number of actuators with varying orientation angles. Results showed that the combination of 4 mm wall thickness and 8 actuators with 90 degrees orientation performed best in the design domain.

Design, simulation, and fabrication of a three-dimensional printed pump mimicking the left ventricle motion

The development of accurate replicas of the circulatory and cardiac system is fundamental for a deeper understanding of cardiovascular diseases and the testing of new devices. Although numerous works concerning mock circulatory loops are present in the current state of the art, still some limitations are present. In particular, a pumping system able to reproduce the left ventricle motion and completely compatible with the magnetic resonance environment to permit the four-dimensional flow monitoring is still missing. The aim of this work was to evaluate the feasibility of an actuator suitable for cardiovascular mock circuits. Particular attention was given to the ability to mimic the left ventricle dynamics including both compression and twisting with the magnetic resonance compatibility. In our study, a left ventricle model to be actuated through vacuum was designed. The realization of the system was evaluated with finite element analysis of different design solutions. After the in silico evaluation phase, the most suitable design in terms of physiological values reproduction was fabricated through three-dimensional printing for in vitro validation. A pneumatic experimental setup was developed to evaluate the pump performances in terms of actuation, in particular ventricle radial and longitudinal displacement, twist rotation, and ejection fraction. The study demonstrated the feasibility of a custom pneumatic pump for mock circulatory loops able to reproduce the physiological ventricle movement and completely suitable for the magnetic resonance environment.

Practical tips and tricks in measuring strain, strain rate and twist for the left and right ventricles

Strain imaging provides an accessible, feasible and non-invasive technique to assess cardiac mechanics. Speckle tracking echocardiography (STE) is the primary modality with the utility for detection of subclinical ventricular dysfunction. Investigation and adoption of this technique has increased significantly in both the research and clinical environment. It is therefore important to provide information to guide the sonographer on the production of valid and reproducible data. The focus of this review is to (1) describe cardiac physiology and mechanics relevant to strain imaging, (2) discuss the concepts of strain imaging and STE and (3) provide a practical guide for the investigation and interpretation of cardiac mechanics using STE.

Computational modeling of human left ventricle to assess the role of trabeculae carneae on the diastolic and systolic functions

Trabeculae carneae are irregular structures that cover the endocardial surfaces of both ventricles and account for a significant portion of human ventricular mass. The role of trabeculae carneae in diastolic and systolic functions of the left ventricle (LV) is not well understood. Thus, the objective of this study was to investigate the functional role of trabeculae carneae in the LV. Finite element analyses of ventricular functions were conducted for three different models of human LV derived from high-resolution magnetic resonance imaging (MRI). The first model comprised trabeculae carneae and papillary muscles, while the second model had papillary muscles and partial trabeculae carneae, and the third model had a smooth endocardial surface. We customized these patient-specific models with myofiber architecture generated with a rule-based algorithm, diastolic material parameters using Fung strain energy function derived from bi-axial tests and adjusted with the empirical Klotz relationship, and myocardial contractility constants optimized for average normal ejection fraction of the human LV. Results showed that the partial trabeculae cutting model had enlarged end-diastolic volume, reduced wall stiffness and even increased end-systolic function, indicating that the absence of trabeculae carneae increased the compliance of the LV during diastole, while maintaining systolic function.

Dipyridamole-Induced Left Ventricular "Rigid Body Rotation" (A Case from the Three-Dimensional Speckle Tracking Echocardiographic MAGYAR-Stress Study)

Under normal physiological conditions, the direction of systolic rotation of the left ventricular (LV) base is clockwise, and that of the LV apex is counterclockwise resulting in the wringing motion of the LV around its long axis called as LV twist. The present study was designed to present a patient with significant coronary artery disease in whom near absence of LV twist called as LV rigid body rotation could be induced during dipyridamole stress as assessed noninvasively by three-dimensional speckle-tracking echocardiography.

The Year in Perioperative Echocardiography: Selected Highlights from 2018

This article is the third of an annual series reviewing the research highlights of the year pertaining to the subspecialty of perioperative echocardiography for the Journal of Cardiothoracic and Vascular Anesthesia. The authors thank the editor-in-chief, Dr. Kaplan, and the editorial board for the opportunity to continue this series. In most cases, these will be research articles targeted at the perioperative echocardiography diagnosis and treatment of patients after cardiothoracic surgery; but in some cases, these articles will target the use of perioperative echocardiography in general.

Cardiovascular Evaluation of Children With Malignancies

PURPOSE OF REVIEW

The anthracycline (AC) group of drugs is widely used for cancer chemotherapy and has improved outcomes in many childhood malignancies. However, cardiovascular complications are major causes of morbidity and mortality in AC recipients, with the greatest risk factor being a higher cumulative dosage. The purpose of this review is to describe the etio-pathogenesis and risk factors of AC induced cardiotoxicity, with emphasis on currently available and emerging modalities of non-invasive imaging in its surveillance, and to review guidelines on its prevention and treatment.

RECENT FINDINGS

Presently, ejection fraction and shortening fraction derived from two-dimensional echocardiography are the most widely used parameter for monitoring of cardiac function in childhood cancer survivors. The newer speckle tracking echocardiography has shown potential to detect abnormalities in ventricular function prior to the conventional measures such as ejection fraction and shortening fraction. When available, three-dimensional echocardiography should be used as it allows for more accurate estimation of ejection fraction. Newer magnetic resonance imaging (MRI) techniques, such as delayed enhancement and T1 mapping, are useful adjuncts for cardiac evaluation in cancer survivors, especially in patients with poor echocardiographic windows. Early detection and management of cardiovascular diseases is one of the major goals in the long-term follow-up of childhood cancer survivors. In addition to conventional two-dimensional echocardiography, newer techniques such as speckle tracking echocardiography and three-dimensional echocardiography should be incorporated due to its ability to detect early changes in anthracycline-induced cardiotoxicity. However further research are needed to guide changes in management due to abnormalities in speckle tracking echocardiography.

Normal values of left ventricular rotational parameters in healthy adults-Insights from the three-dimensional speckle tracking echocardiographic MAGYAR-Healthy Study

INTRODUCTION

Left ventricular (LV) rotation and twist are essential parts of LV function. Three-dimensional speckle tracking echocardiography (3DSTE) is a relatively new method and is useful for the quantification of LV wall deformation and rotational parameters. The aim of the present study was to examine LV rotation and twist differences between different age-groups and genders in a healthy population.

METHODS

The present study is comprised of 297 healthy adults; 120 adults have been excluded due to inferior image quality. The population was further divided into 4 subgroups based on age decades.

RESULTS

Only the LV twist of all patients (13.5 ± 3.7 degree vs 15.6 ± 4.9 degree, P = 0.02) and the LV twist of females (13.0 ± 3.6 degree vs 15.5 ± 5.6 degree, P = 0.03) differed significantly between the age-group of 18-29 years and 50+ years. LV basal and apical rotation were not significantly different between the age-groups; however, they tendentiously increased with aging. No significant differences could be demonstrated regarding LV rotational and twist parameters between genders in any group. A phenomenon called LV rigid body rotation (LV-RBR)-where the base and apex of the LV rotate in the same direction-was present in 10 cases.

CONCLUSIONS

Three-dimensional speckle tracking echocardiography seems to be a reasonably viable tool for the quantification of LV rotation and twist. Both LV basal and apical rotation and LV twist increase with aging, regardless of gender. LV-RBR is also present in the normal population.

Structural and Biomechanical Adaptations of Right Ventricular Remodeling - in Pulmonary Arterial Hypertension - Reduces Left Ventricular Rotation During Contraction: A Computational Study

Pulmonary hypertension (PH) is a degenerative disease characterized by progressively increased right ventricular (RV) afterload that leads to ultimate functional decline [1]. Recent observational studies have documented a decrease in left ventricular (LV) torsion during ejection, with preserved LV ejection fraction (EF) in pediatric and adult PH patients [2-4]. The objective of this study was to develop a computational model of the bi-ventricular heart and use it to evaluate changes in LV torsion mechanics in response to mechanical, structural, and hemodynamic changes in the RV free-wall. The heart model revealed that LV apex rotation and torsion were decreased when increasing RV mechanical rigidity and during re-orientation of RV myocardial fibers. Furthermore, structural changes to the RV appear to have a notable impact on RV EF, but little influence on LV EF. Finally, RV pressure overload exponentially increased LV myocardial stress. The computational results found in this study are consistent with clinical observations in adult and pediatric PH patients, which reveal a decrease in LV torsion with preserved LV EF [3, 4]. Furthermore, discovered causes of decreased LV torsion are consistent with RV structural adaptations seen in PH rodent studies [5], which might also explain suspected stress-induced changes in LV myocardial gene/protein expression.

Left ventricular rotational abnormalities following successful kidney transplantation-insights from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study

Background

Kidney transplantation (KTx) is the preferred treatment for virtually all suitable candidates with end-stage renal disease. There is limited information on left ventricular (LV) rotational mechanics post-KTx, therefore the present study aimed to assess it and to compare it to that of age- and gender-matched healthy controls.

Methods

The present study comprised 42 KTx patients, from which 4 patients were excluded due to insufficient image quality (mean age: 46.3±8.2 years, 29 males). Control group consisted of 81 age- and gender-matched healthy individuals (mean age: 43.5±10.8 years, 51 males). All KTx patients and healthy controls successfully underwent transthoracic two-dimensional (2D) Doppler echocardiography and three-dimensional speckle-tracking echocardiography (3DSTE).

Results

Significant differences could be demonstrated in LA diameter, LV end-diastolic diameter and volume, interventricular septum, LV posterior wall thickness, LV ejection fraction and early and late filling transmitral flow velocities and in their ratio between KTx patients and controls; none of the subjects examined showed grade 2-4 mitral and/or tricuspid regurgitations. Three patients following successful KTx showed near absence of LV twist called as LV 'rigid body rotation' (RBR) movement. When the remaining 35 post-KTx patients were analysed separately, reduced basal LV rotation could be demonstrated in post-KTx patients with tendentious increase in apical LV rotation resulting in an unchanged LV twist.

Conclusions

KTx is associated with alterations in LV rotational mechanics with unchanged LV twist suggesting a remodelling of this sort of movement. The near absence of LV twist (LV-RBR) could be demonstrated in some post-KTx cases.

The Influence of Rotary Blood Pump Speed Modulation on the Risk of Intraventricular Thrombosis

Rotary left ventricular assist devices (LVADs) are commonly operated at a constant speed, attenuating blood flow pulsatility. Speed modulation of rotary LVADs has been demonstrated to improve vascular pulsatility and pump washout. The effect of LVAD speed modulation on intraventricular flow dynamics is not well understood, which may have an influence on thromboembolic events. This study aimed to numerically evaluate intraventricular flow characteristics with a speed modulated LVAD. A severely dilated anatomical left ventricle was supported by a HeartWare HVAD in a three-dimensional multiscale computational fluid dynamics model. Three LVAD operating scenarios were evaluated: constant speed and sinusoidal co- and counter-pulsation. In all operating scenarios, the mean pump speed was set to restore the cardiac output to 5.0 L/min. Co- and counter-pulsation was speed modulated with an amplitude of 750 rpm. The risk of thrombosis was evaluated based on blood residence time, ventricular washout, kinetic energy densities, and a pulsatility index map. Blood residence time for co-pulsation was on average 1.8 and 3.7% lower than constant speed and counter-pulsation mode, respectively. After introducing fresh blood to displace preexisting blood for 10 cardiac cycles, co-pulsation had 1.5% less old blood in comparison to counter-pulsation. Apical energy densities were 84 and 27% higher for co-pulsation in comparison to counter-pulsation and constant speed mode, respectively. Co-pulsation had an increased pulsatility index around the left ventricular outflow tract and mid-ventricle. Improved flow dynamics with co-pulsation was caused by increased E-wave velocities which minimized blood stasis. In the studied scenario and from the perspective of intraventricular flow dynamics, co-pulsation of rotary LVADs could minimize the risk of intraventricular thrombosis.

Can We Engineer a Human Cardiac Patch for Therapy?

Some of the most significant leaps in the history of modern civilization-the development of article in China, the steam engine, which led to the European industrial revolution, and the era of computers-have occurred when science converged with engineering. Recently, the convergence of human pluripotent stem cell technology with biomaterials and bioengineering have launched a new medical innovation: functional human engineered tissue, which promises to revolutionize the treatment of failing organs including most critically, the heart. This compendium covers recent, state-of-the-art developments in the fields of cardiovascular tissue engineering, as well as the needs and challenges associated with the clinical use of these technologies. We have not attempted to provide an exhaustive review in stem cell biology and cardiac cell therapy; many other important and influential reports are certainly merit but already been discussed in several recent reviews. Our scope is limited to the engineered tissues that have been fabricated to repair or replace components of the heart (eg, valves, vessels, contractile tissue) that have been functionally compromised by diseases or developmental abnormalities. In particular, we have focused on using an engineered myocardial tissue to mitigate deficiencies in contractile function.

Left Ventricular Speckle Tracking-Derived Cardiac Strain and Cardiac Twist Mechanics in Athletes: A Systematic Review and Meta-Analysis of Controlled Studies

Background

The athlete’s heart is associated with physiological remodeling as a consequence of repetitive cardiac loading. The effect of exercise training on left ventricular (LV) cardiac strain and twist mechanics are equivocal, and no meta-analysis has been conducted to date.

Objective

The objective of this systematic review and meta-analysis was to review the literature pertaining to the effect of different forms of athletic training on cardiac strain and twist mechanics and determine the influence of traditional and contemporary sporting classifications on cardiac strain and twist mechanics.

Methods

We searched PubMed/MEDLINE, Web of Science, and ScienceDirect for controlled studies of aged-matched male participants aged 18–45 years that used two-dimensional (2D) speckle tracking with a defined athlete sporting discipline and a control group not engaged in training programs. Data were extracted independently by two reviewers. Random-effects meta-analyses, subgroup analyses, and meta-regressions were conducted.

Results

Our review included 13 studies with 945 participants (controls n = 355; athletes n = 590). Meta-analyses showed no athlete–control differences in LV strain or twist mechanics. However, moderator analyses showed greater LV twist in high-static low-dynamic athletes (d = –0.76, 95% confidence interval [CI] –1.32 to –0.20; p < 0.01) than in controls. Peak untwisting velocity (PUV) was greater in high-static low-dynamic athletes (d = –0.43, 95% CI –0.84 to –0.03; p < 0.05) but less than controls in high-static high-dynamic athletes (d = 0.79, 95% CI 0.002–1.58; p = 0.05). Elite endurance athletes had significantly less twist and apical rotation than controls (d = 0.68, 95% CI 0.19–1.16, p < 0.01; d = 0.64, 95% CI 0.27–1.00, p = 0.001, respectively) but no differences in basal rotation. Meta-regressions showed LV mass index was positively associated with global longitudinal (b = 0.01, 95% CI 0.002–0.02; p < 0.05), whereas systolic blood pressure was negatively associated with PUV (b = –0.06, 95% CI –0.13 to –0.001; p = 0.05).

Conclusion

Echocardiographic 2D speckle tracking can identify subtle physiological differences in adaptations to cardiac strain and twist mechanics between athletes and healthy controls. Differences in speckle tracking echocardiography-derived parameters can be identified using suitable sporting categorizations.

Left ventricular twist before and after haemodialysis: an analysis using speckle-tracking echocardiography

Background

The most commonly used parameter of cardiac function in the chronic kidney disease (CKD) patient is ejection fraction (EF), using transthoracic echocardiography (TTE). EF is a highly load-dependent measurement, which varies considerably in CKD patients undergoing haemodialysis. The aim of this pilot study was to evaluate a novel measure of myocardial function, left ventricular twist, which is defined as the ‘wringing action of the heart’, using speckletracking echocardiography in CKD patients before and after haemodialysis.

Methods

Twenty-six patients were recruited from the Chris Hani Baragwanath Hospital haemodialysis unit. TTE was performed according to a detailed standardised protocol before and after a single haemodialysis session. Echocardiography was also performed on 26 age- and gendermatched healthy subjects.

Results

The mean age of the control versus CKD group was 44 ± 11.4 and 43.4 ± 12.2 years, respectively; 46% were male. Apical rotation was diminished in CKD patients compared to controls (4.83 ± 2.3 vs 6.31 ± 1.6 °; p = 0.01) despite no difference in EF (61.7 ± 6.2 vs 58.8 ± 13; p = 0.68). There were no differences in the components of twist: apical rotation, basal rotation and net twist before and after dialysis, despite an increase in EF (58.8 ± 13.7 vs 61.2 ± 13.6; p = 0.02) following dialysis.

Conclusion

Unlike EF, the components of twist are relatively independent of changes in haemodynamic load seen during dialysis. The decrease in apical rotation may represent an early marker of cardiac pathology in the late-stage CKD patient.

Echo and heart failure: when do people need an echo, and when do they need natriuretic peptides?

Heart failure (HF) is a threat to public health. Heterogeneities in aetiology and phenotype complicate the diagnosis and management of HF. This is especially true when considering HF with preserved ejection fraction (HFpEF), which makes up 50% of HF cases. Natriuretic peptides may aid in establishing a working diagnosis in patients suspected of HF, but echocardiography remains the optimal choice for diagnosing HF. Echocardiography provides important prognostic information in both HF with reduced ejection fraction (HFrEF) and HFpEF. Traditionally, emphasis has been put on the left ventricular ejection fraction (LVEF). LVEF is useful for both diagnosis and prognosis in HFrEF. However, echocardiography offers more than this single parameter of systolic function, and for optimal risk assessment in HFrEF, an echocardiogram evaluating systolic, diastolic, left atrial and right ventricular function is beneficial. In this assessment echocardiographic modalities such as global longitudinal strain (GLS) by 2D speckle-tracking may be useful. LVEF offers little value in HFpEF and is neither helpful for diagnosis nor prognosis. Diastolic function quantified by E/e′ and systolic function determined by GLS offer prognostic insight in HFpEF. In HFpEF, other parameters of cardiac performance such as left atrial and right ventricular function evaluated by echocardiography also contribute with prognostic information. Hence, it is important to consider the entire echocardiogram and not focus solely on systolic function. Future research should focus on combining echocardiographic parameters into risk prediction models to adopt a more personalized approach to prognosis instead of identifying yet another echocardiographic biomarker.

A multidimensional sight on cardiac failure: uncovered from structural to molecular level

Heart failure is one of the leading causes of death, with high mortality rate within 5 years after diagnosis. Treatment and prognosis options for heart failure primarily targeted on hemodynamic and neurohumoral components that drive progressive deterioration of the heart. However, given the multifactorial background that eventually leads to the "phenotype" named heart failure, better insight into the various components may lead to personalized treatment opportunities. Indeed, currently used criteria to diagnose and/or classify heart failure are possibly too focused on phenotypic improvement rather than the molecular driver of the disease and could therefore be further refined by integrating the leap of molecular and cellular knowledge. The ambiguity of the ejection fraction-based classification criteria became evident with development of advanced molecular techniques and the dawn of omics disciplines which introduced the idea that disease is caused by a myriad of cellular and molecular processes rather than a single event or pathway. The fact that different signaling pathways may underlie similar clinical manifestations calls for a more holistic study of heart failure. In this context, the systems biology approach can offer a better understanding of how different components of a system are altered during disease and how they interact with each other, potentially leading to improved diagnosis and classification of this condition. This review is aimed at addressing heart failure through a multilayer approach that covers individually some of the anatomical, morphological, functional, and tissue aspects, with focus on cellular and subcellular features as an alternative insight into new therapeutic opportunities.

Left Ventricular Torsion Associated With Aortic Stiffness in Hypertension

BACKGROUND

Left ventricular (LV) torsion plays a key role in cardiac efficiency. In hypertension, aortic stiffening augments cardiac afterload. However, little is known about the links between LV regional contraction and aortic stiffness. We, therefore, investigated these relationships and their contribution to LV diastolic function.

METHODS AND RESULTS

The study included normotensive and hypertensive individuals with normal LV ejection. Apical, basal, and global LV rotation rate and LV global longitudinal strain were measured (2-dimensional speckle tracking echocardiography). Aortic stiffness was calculated from carotid-femoral pulse wave velocity, and LV relaxation was calculated from early diastolic mitral annulus motion. The ratio of basal or apical untwist/twist rates was calculated to assess relationships between aortic stiffness and LV torsion parameters. LV twist and untwist rates were greater in hypertensive than normotensive individuals because of increased basal twist (P<0.001) and untwist (P<0.001) rates. LV relaxation was reduced (early diastolic mitral annulus motion=7.4±1.9 versus 10.4±2.3 cm/s; P<0.001). In the whole population, basal untwist rate increased with aortic stiffening (R=0.43; P<0.001) and LV relaxation (R=0.41; P=0.001). The ratio of basal untwist/twist rate was positively correlated with carotid-femoral pulse wave velocity, and in the hypertensive group, was greater than in the control group and positively correlated to carotid-femoral pulse wave velocity(P<0.001). Results were independent of age, treatment, mean blood pressure, and indexed LV mass.

CONCLUSIONS

In hypertensive individuals, greater basal LV torsion was associated with increased aortic stiffness and improved diastolic function. These changes may compensate for the deleterious effects of aortic stiffening on LV relaxation.

Change of left ventricular "rigid body rotation" during dipyridamole-induced vasodilation: A case from the three-dimensional speckle tracking echocardiographic MAGYAR-Stress Study

A patient with previous coronary stenting presented with stable angina and positive exercise treadmill test. Echocardiography with three-dimensional speckle-tracking demonstrated left ventricular rigid body rotation (near absence of left ventricular twist), whose characteristics changed dramatically during dipyridamole-induced vasodilatation. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:152-156, 2018.

Left ventricular deformation abnormalities in a patient with calpainopathy-a case from the three-dimensional speckle-tracking echocardiographic MAGYAR-Path Study

Calpainopathy or limb-girdle muscular dystrophy type 2A (LGMD2A) is the most common type of autosomal recessive limb-girdle muscular dystrophies. The disease is caused by mutations in the CAPN3 gene encoding calpain, a protein involved in muscle membrane remodeling and repair. This paper gives an overview of the genetic background, clinical course, and diagnosis of the disease, and presents the first case of calpainopathy in which cardiac deformation mechanics was investigated. Three-dimensional speckle-tracking echocardiography (3DSTE) demonstrated reduced left ventricular (LV) strains and increased LV apical rotation and twist, suggestive of asymptomatic subclinical LV dysfunction. Cardiac involvement has not been previously reported in calpainopathy.

Reference ranges for three-dimensional feature tracking cardiac magnetic resonance: comparison with two-dimensional methodology and relevance of age and gender

Myocardial deformation is a sensitive marker of sub-clinical myocardial dysfunction that carries independent prognostic significance across a broad range of cardiovascular diseases. It is now possible to perform 3D feature tracking of SSFP cines on cardiac magnetic resonance imaging (FT-CMR). This study provides reference ranges for 3D FT-CMR and assesses its reproducibility compared to 2D FT-CMR. One hundred healthy individuals with 10 men and women in each of 5 age deciles from 20 to 70 years, underwent 2D and 3D FT-CMR of left ventricular myocardial strain and strain rate using SSFP cines. Good health was defined by the absence of hypertension, diabetes, obesity, dyslipidaemia, or any cardiovascular, renal, hepatic, haematological and systemic inflammatory disease. Normal values for myocardial strain assessed by 3D FT-CMR were consistently lower compared with 2D FT-CMR measures [global circumferential strain (GCS) 3D − 17.6 ± 2.6% vs. 2D − 20.9 ± 3.7%, P < 0.005]. Validity of 3D FT-CMR was confirmed against other markers of systolic function. The 3D algorithm improved reproducibility compared to 2D, with GCS having the best inter-observer agreement [intra-class correlation (ICC) 0.88], followed by global radial strain (GRS; ICC 0.79) and global longitudinal strain (GLS, ICC 0.74). On linear regression analyses, increasing age was weakly associated with increased GCS (R² = 0.15, R = 0.38), peak systolic strain rate, peak late diastolic strain rate, and lower peak early systolic strain rate. 3D FT-CMR offers superior reproducibility compared to 2D FT-CMR, with circumferential strain and strain rates offering excellent intra- and inter-observer variability. Normal range values for myocardial strain measurements using 3D FT-CMR are provided.

Pyridoxamine improves survival and limits cardiac dysfunction after MI

Advanced glycation end products (AGEs) play a key role in the progression of heart failure. Whether treatments limiting AGEs formation would prevent adverse left ventricular remodeling after myocardial infarction (MI) remain unknown. We investigated whether pyridoxamine (PM) could limit adverse cardiac outcome in MI. Rats were divided into MI, MI + PM and Sham. Echocardiography and hemodynamic parameters were used to assess cardiac function 8 weeks post-surgery. Total interstitial collagen, collagen I and collagen III were quantified using Sirius Red and polarized light microscopy. PM improved survival following LAD occlusion. Pre-treatment with PM significantly decreased the plasma AGEs levels. MI rats treated with PM displayed reduced left ventricular end-diastolic pressure and tau compared to untreated MI rats. Deformation parameters were also improved with PM. The preserved diastolic function was related to the reduced collagen content, in particular in the highly cross-linked collagen type I, mainly in the peri-infarct region, although not via TGF-β1 pathway. Our data indicate that PM treatment prevents the increase in AGEs levels and reduces collagen levels in a rat model of MI, resulting in an improved cardiac phenotype. As such, therapies targeting formation of AGEs might be beneficial in the prevention and/or treatment of maladaptive remodeling following MI.

Magnetic resonance imaging of myocardial strain: A review of current approaches

Contraction of the heart is central to its purpose of pumping blood around the body. While simple global function measures (such as the ejection fraction) are most commonly used in the clinical assessment of cardiac function, MRI also provides a range of approaches for quantitatively characterizing regional cardiac function, including the local deformation (or strain) within the heart wall. While they have been around for some years, these methods are still undergoing further technical development, and they have had relatively little clinical evaluation. However, they can provide potentially useful new ways to assess cardiac function, which may be able to contribute to better classification and treatment of heart disease. This article provides some basic background on the physical and physiological factors that determine the motion of the heart, in health and disease and then reviews some of the ways that MRI methods are being developed to image and quantify strain within the myocardium.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1263-1280.

A mock heart engineered with helical aramid fibers for in vitro cardiovascular device testing

Mock heart circulation loops (MHCLs) serve as in-vitro platforms to investigate the physiological interaction between circulatory systems and cardiovascular devices. A mock heart (MH) engineered with silicone walls and helical aramid fibers, to mimic the complex contraction of a natural heart, has been developed to advance the MHCL previously developed in our group. A mock aorta with an anatomical shape enables the evaluation of a cannulation method for ventricular assist devices (VADs) and investigation of the usage of clinical measurement systems like pressure-volume catheters. Ventricle and aorta molds were produced based on MRI data and cast with silicone. Aramid fibers were layered in the silicone ventricle to reproduce ventricle torsion. A rotating hollow shaft was connected to the apex enabling the rotation of the MH and the connection of a VAD. Silicone wall thickness, aramid fiber angle and fiber pitch were varied to generate different MH models. All MH models were placed in a tank filled with variable amounts of water and air simulating the compliance. In this work, physiological ventricular torsion angles (15°-26°) and physiological pressure-volume loops were achieved. This MHCL can serve as a comprehensive testing platform for cardiovascular devices, such as artificial heart valves and cannulation of VADs.

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.

Timing of the negative effects of trastuzumab on cardiac mechanics after anthracycline chemotherapy

Trastuzumab (TZB) has been shown to be extremely effective in breast cancer patients over-expressing HER-2, but careful cardiac monitoring is required when TZB is administered with anthracyclines, since the combination can increase its toxicity. Myocardial deformation indexes associated with speckle tracking echocardiography (STE) have proven to be very sensitive in identifying early myocardial dysfunction. An observational, prospective study was designed to assess TZB-induced cardiac damage using STE in patients with HER-2 positive breast cancer who had been sequentially treated with TZB following epirubicin (EPI). Conventional echocardiographic parameters and STE deformation indexes (longitudinal, radial, and circumferential strain/strain rate and apical rotation) were analyzed at baseline, after each EPI treatment, and 1 week after every other dose of TZB administration until 1 year follow up, in order to focus on the timing and extent of myocardial impairment. In the forty-five enrolled patients, a reduction in subendocardial function after EPI treatment was observed by a significant impairment of the global longitudinal strain/strain rate (GLS/SR), while a significant increase in the activity of the subepicardial fibers was highlighted by an increase in apical rotation. After the second TZB dose, a sudden reduction of the apical rotation was seen, together with circumferential and radial strain/SR. Most importantly, the extent to which the apical rotation increased and decreased was found to strictly correlate with the GLS reduction at follow up. We found that after EPI therapy, subendocardial function was impaired, even while a compensatory increase in apical rotation occurred. Following TZB treatment, we observed impairment in apical rotation, which seems to be the first sign of global LV dysfunction predicting GLS reduction found at the end of treatment.

Non-Invasive Evaluation of Heart Function with Four-Dimensional Echocardiography

Background

The aim of this study is to assess the accuracy and feasibility of left ventricular systolic function determined by four-dimensional echocardiography (4DE).

Methods

Latex balloons were sewn into the left ventricle (LV) of 20 freshly harvested pig hearts which were then passively driven by a pulsatile pump apparatus. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS) and left ventricular ejection fraction (LVEF) derived from 4DEand two-dimensional echocardiography (2DE)-derived LVEF were quantified at different stroke volumes (SV) 30–70 ml and correlated with sonomicrometry data.

Results

In all comparisons, GLS, GCS, GAS, 2DE-LVEF, and 4DE-LVEF demonstrated strong correlations with sonomicrometry data (r = 0.77, r = 0.89, r = 0.79, r = 0.93, r = 0.96, all P <0.001). Bland-Altman analyses showed slight overestimations of echo-derived GLS, GCS, 2DE-LVEF and 3DE-LVEF over sonomicrometry values (bias = 2.88, bias = 3.99, bias = 3.37, bias = 2.78, respectively). Furthermore, there is better agreement between GCS, 4D LVEF and sonomicrometry values compared with GLS and 2D LVEF.

Conclusion

Four-dimensional echocardiography accurately assesses LV function. GCS derived by 4DE is a potential alternative parameter to quantify LV systolic function.

Relationship between left ventricular mechanics and low free triiodothyronine levels after myocardial infarction: a prospective study

Low free triiodothyronine (fT3) levels following acute myocardial infarction (AMI) are associated with greater impairment in cardiac mechanics compared with patients with AMI who have normal values of thyroid hormones. The objectives are to investigate left ventricular (LV) function and mechanics during a 6-month follow-up after myocardial infarction and to evaluate their prognostic implication using two-dimensional (2D) echocardiography and 2D speckle-tracking echocardiography in patients with low fT3 levels. The study design is prospective cohort study. One hundred forty patients with first-onset AMI were grouped according to serum fT3 levels: low fT3 group (fT3 <3.2 pmol/L; n = 44) and control group (fT3 >3.2 pmol/L; n = 96). Low levels of fT3 were associated with greater LV diameters and LV end-diastolic volume, and decreased systolic LV function. Systolic apical and basal rotation, peak systolic global longitudinal strain and strain rate, and LV twist and torsion were significantly decreased in the low fT3 group. The prognostic implication for predicting low fT3 levels was evaluated using ROC analysis. LV end-diastolic diameter index is the most sensitive (94.12 %), but has low specificity (37.93 %; area = 0.659, p = 0.01). By contrast, LV end-systolic volume is the most specific (94.03 %), but has low sensitivity (26.32 %; area = 0.594, p = 0.04). Low fT3 levels are significantly associated with worse LV mechanics. Low fT3 levels are important for prediction of LV structure, function, rotation, and deformation parameters during the late post-myocardial infarction period.

Mechanical effects of left ventricular midwall fibrosis in non-ischemic cardiomyopathy

BACKGROUND

Left ventricular (LV) mid-wall fibrosis (MWF), which occurs in about a quarter of patients with non-ischemic cardiomyopathy (NICM), is associated with high risk of pump failure. The mid LV wall is the site of circumferential myocardial fibers. We sought to determine the effect of MWF on LV myocardial mechanics.

METHODS

Patients with NICM (n = 116; age: 62.8 ± 13.2 years; 67% male) underwent late gadolinium enhancement cardiovascular magnetic resonance (CMR) and were categorized according to the presence (+) or absence (-) of MWF. Feature tracking (FT) CMR was used to assess myocardial deformation.

RESULTS

Despite a similar LVEF (24.3 vs. 27.5%, p = 0.20), patients with MWF (32 [24%]) had lower global circumferential strain (Ɛcc: -6.6% vs. -9.4 %, P = 0.004), but similar longitudinal (Ɛll: -7.6 % vs. -9.4 %, p = 0.053) and radial (Ɛrr: 14.6% vs. 17.8% p = 0.18) strain. Compared with - MWF, + MWF was associated with reduced LV systolic, circumferential strain rate (-0.38 ± 0.1 vs. -0.56 ± 0.3 s(-1), p = 0.005) and peak LV twist (4.65 vs. 6.31°, p = 0.004), as well as rigid LV body rotation (64 % vs. 28 %, P <0.001). In addition, +MWF was associated with reduced LV diastolic strain rates (DSRcc: 0.34 vs. 0.46 s(-1); DSRll: 0.38 vs. 0.50s(-1); DSRrr: -0.55 vs. -0.75 s(-1); all p <0.05).

CONCLUSIONS

MWF is associated with reduced LV global circumferential strain, strain rate and torsion. In addition, MWF is associated with rigid LV body rotation and reduced diastolic strain rates. These systolic and diastolic disturbances may be related to the increased risk of pump failure observed in patients with NICM and MWF.

Left Ventricular Systolic Function Changes in Primary Hypertension Patients Detected by the Strain of Different Myocardium Layers

This study investigated left ventricular (LV) systolic dysfunction associated with differential strain among myocardial layers in primary hypertension (PH) patients with or without LV hypertrophy (LVH), and normal patients.In 63 PH and 42 healthy patients, two-dimensional speckle tracking echocardiography was used to measure the peak systolic longitudinal and circumferential strain of the myocardial subendocardial, middle and subepicardial layers, and the peak systolic radial strain. To assess LV systolic function, the apical long axis, 4- and 2-chamber views, and parasternal short axis at the basal, middle, and apical levels were acquired by cardiovascular ultrasound (Vivid E9, GE Healthcare, USA).Overall, the pattern in peak systolic longitudinal strain among myocardial layers was subendocardial > middle > subepicardial. In the peak systolic circumferential strain, this was middle > subepicardial > subendocardial. The peak systolic longitudinal strain was normal > NLVH > LVH. Among the groups, the peak systolic circumferential strain at the basal parasternal short-axis level was statistically similar, but at the middle and the apical parasternal short-axis levels were NLVH > normal > LVH. In normal and NLVH patients, the peak radial strain was middle > apical > basal, and in LVH patients was apical > middle > basal. The peak averages of the longitudinal and subendocardial circumferential strains differed significantly when LVH compared with NLVH and normal patients.The systolic function of PH patients was damaged in comparison with normal individuals, which could be detected conveniently and accurately using two-dimensional speckle tracking echocardiography.

BIOMECHANICS OF POSITIVE INTRATHORACIC PRESSURE AND ITS EFFECTS ON LEFT VENTRICULAR FILLING IN HEALTHY SUBJECTS

This study aims to explore the biomechanics of positive intrathoracic pressure and its effects on left ventricle (LV) filling in healthy subjects. 30 healthy subjects were enlisted to perform a Valsalva maneuver (VM) with a load of 40[Formula: see text]mmHg lasted 10[Formula: see text]s. LV filling parameters were measured by echocardiography at rest and at 10[Formula: see text]s during the VM. Compared with the at rest values, LV early inflow velocity (E) decreased significantly ([Formula: see text]), late inflow velocity (A) decreased insignificantly ([Formula: see text]), while the E/A ratio decreased significantly ([Formula: see text]) after 10[Formula: see text]s of the strain phase of the VM. LV septal early tissue velocity ([Formula: see text]) and lateral early tissue velocity ([Formula: see text]) of the mitral did not change ([Formula: see text]), while the [Formula: see text] ratio and the [Formula: see text] ratio decreased significantly ([Formula: see text] after 10[Formula: see text]s during the VM. Based on these results, biomechanical analysis suggests that the effects of positive intrathoracic pressure on the LV free wall impede LV diastolic motion, which may be one of the factors contributing to a decrease in E and the E/A ratio. Positive intrathoracic pressure also increases the flow resistance of the LV and pulmonary vasculature, which may contribute to a decrease in E, the [Formula: see text] ratio, and the [Formula: see text] ratio.

Patients with Diabetes and Significant Epicardial Coronary Artery Disease Have Increased Systolic Left Ventricular Apical Rotation and Rotation Rate at Rest

OBJECTIVE

The purpose of this study was to determine whether resting myocardial deformation and rotation may be altered in diabetic patients with significant epicardial coronary artery disease (CAD) with normal left ventricular ejection fraction.

DESIGN

A prospective observational study.

SETTING

Diagnosis of epicardial CAD in patients with diabetes.

PATIENTS AND METHODS

Eighty-four patients with diabetes suspected of epicardial CAD scheduled for cardiac catheterization had a resting echocardiogram performed prior to their procedure. Echocardiographic measurements were compared between patients with and without significant epicardial CAD as determined by cardiac catheterization.

MAIN OUTCOME MEASURES

Measurement of longitudinal strain, strain rate, apical rotation, and rotation rate, using speckle tracking echocardiography.

RESULTS

Eighty-four patients were studied, 39 (46.4%) of whom had significant epicardial CAD. Global peak systolic apical rotation was significantly increased (14.9 ± 5.1 vs. 11.0 ± 4.8 degrees, P < 0.001) in patients with epicardial CAD along with faster peak systolic apical rotation rate (90.4 ± 29 vs. 68.1 ± 22.2 degrees/sec, P < 0.001). These findings were further confirmed through multivariate logistic regression analysis (global peak systolic apical rotation OR = 1.17, P = 0.004 and peak systolic apical rotation rate OR = 1.05, P < 0.001).

CONCLUSIONS

Patients with diabetes with significant epicardial CAD and normal LVEF exhibit an increase in peak systolic apical counterclockwise rotation and rotation rate detected by echocardiography, suggesting that significant epicardial CAD and its associated myocardial effects in patients with diabetes may be detected noninvasively at rest.

Different responses of the myocardial contractility by layer following acute pressure unloading in severe aortic stenosis patients

The present study evaluated change in left ventricle (LV) biomechanics, layer-by-layer, following acute pressure unloading in patients with severe aortic stenosis (AS). In twenty-eight consecutive patients with severe AS who underwent transcatheter aortic valve replacement (TAVR), LV peak global longitudinal and circumferential strains of the endo-, midmyo- and epicardium were evaluated using multilayer speckle tracking echocardiography before, 1 week after, and 1 month after TAVR. Longitudinal and circumferential strains were significantly highest in the endocardium and lowest in the epicardium at baseline. At 1 month following TAVR, longitudinal strain significantly improved in all layers compared with the baseline [endocardium (%) -16.7 ± 3.8 vs. -18.6 ± 3.3, P = 0.01; mid-myocardium -14.4 ± 3.2 vs. -16.2 ± 3.5, P < 0.01; epicardium -12.4 ± 2.8 vs. -13.6 ± 2.6, P = 0.01], whereas LV ejection fraction and circumferential strain remained unchanged. Importantly, only those with LV hypertrophy demonstrated improved longitudinal strain [endocardium (%) -15.7 ± 3.0 vs. -18.7 ± 2.9, P < 0.01; mid-myocardium -13.6 ± 2.7 vs. -16.0 ± 2.5, P < 0.01; epicardium -11.8 ± 2.4 vs. -13.7 ± 2.3, P < 0.01]. The improvement in longitudinal strain was more prominent in the endocardium, which was evident even at an early time point (1 week) after TAVR. Longitudinal strain significantly improved in all three layers following acute pressure unloading, the most prominent of which was observed in the endocardium. Evaluation of multilayer strain may provide new insights into the LV mechanics in the future.

Different implication of elevated B-type natriuretic peptide level in patients with heart failure with preserved ejection fraction and in those with reduced ejection fraction

BACKGROUND

There have been no reports that show significant direct relationship between echocardiographic parameters and B-type natriuretic peptide (BNP) level. This could be due to the heterogeneous pathophysiology of heart failure and a lack of appropriate echocardiographic parameters. We sought to determine the best echocardiographic parameter that described elevated BNP level in patients with heart failure with and without systolic dysfunction.

METHODS AND RESULTS

We studied 111 consecutive heart failure patients. They were divided into patients with heart failure and preserved ejection fraction (HFPEF, n = 61) and that with heart failure and reduced ejection fraction (HFREF, n = 50). Conventional and new echocardiographic parameters including myocardial strains were measured. BNP did not reflect any single echocardiographic parameter in patients with heart failure in total. The ratio of early diastolic transmitral flow velocity and mitral annular velocity had strong positive correlation with BNP level in the HFPEF group but not in the HFREF group. In the group of HFREF, global longitudinal and circumferential strains were positively correlated. Multivariate analysis revealed that predicted factors for BNP value in HFPEF and in HFREF were different.

CONCLUSION

High BNP level may indicate high filling pressure when ejection fraction is preserved and may indicate myocardial dysfunction when it is reduced.

Left ventricular rotation and right-left ventricular interaction in congenital heart disease: the acute effects of interventional closure of patent arterial ducts and atrial septal defects

BACKGROUND

Left ventricular rotation is physiologically affected by acute changes in preload. We investigated the acute effect of preload changes in chronically underloaded and overloaded left ventricles in children with shunt lesions.

METHODS

A total of 15 patients with atrial septal defects (Group A: 7.4 ± 4.7 years, 11 females) and 14 patients with patent arterial ducts (Group B: 2.7 ± 3.1 years, 10 females) were investigated using 2D speckle-tracking echocardiography before and after interventional catheterisation. The rotational parameters of the patient group were compared with those of 29 matched healthy children (Group C).

RESULTS

Maximal torsion (A: 2.45 ± 0.9°/cm versus C: 1.8 ± 0.8°/cm, p < 0.05), apical peak systolic rotation (A: 12.6 ± 5.7° versus C: 8.7 ± 3.5°, p < 0.05), and the peak diastolic torsion rate (A: -147 ± 48°/second versus C: -110 ± 31°/second, p < 0.05) were elevated in Group A and dropped immediately to normal values after intervention (maximal torsion 1.5 ± 1.1°/cm, p < 0.05, apical peak systolic rotation 7.2 ± 4.1°, p < 0.05, and peak diastolic torsion rate -106 ± 35°/second, p < 0.05). Patients in Group B had decreased maximal torsion (B: 1.8 ± 1.1°/cm versus C: 3.8 ± 1.4°/cm, p < 0.05) and apical peak systolic rotation (B: 8.3 ± 6.1° versus C: 13.9 ± 4.3°, p < 0.05). Defect closure was followed by an increase in maximal torsion (B: 2.7 ± 1.4°/cm, p < 0.05) and the peak diastolic torsion rate (B: -133 ± 66°/second versus -176 ± 84°/second, p < 0.05).

CONCLUSIONS

Patients with chronically underloaded left ventricles compensate with an enhanced apical peak systolic rotation, maximal torsion, and quicker diastolic untwisting to facilitate diastolic filling. In patients with left ventricular dilatation by volume overload, the peak systolic apical rotation and the maximal torsion are decreased. After normalisation of the preload, they immediately return to normal and diastolic untwisting rebounds. These mechanisms are important for understanding the remodelling processes.

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.