Left Ventricular Rotation Research Articles

Negative effects of trastuzumab adjuvant chemotherapy on cardiac mechanics. role of specific myocardial layers

Background: Trastuzumab (TZB), an anti HER-2 receptor monoclonal antibody, has been shown to be very effective in patients with breast cancer overexpressing HER-2. It has a mild cardiac toxicity, which may increase when administered in combination with anthracyclines. Anthracycline treatment showed to induce a myocardial overexpression of HER-2 receptors. Myocardial deformation indexes associated with Speckle Tracking (ST) myocardial imaging have shown to be very sensitive identifying left ventricular (LV) dysfunction in this setting. The aim of the study is to assess the effect of TZB therapy on specific myocardial layers after anthracycline treatment. Patients and methods: The study was designed to assess TZB-induced cardiac damage by ST technique in patients with HER-2 positive breast cancer treated with TZB sequentially after Epirubicin treatment. Inclusion criteria: 18–70 yo, histologically confirmed HER-2 positive breast cancer, candidates for TZB-based regimen; LVEF ≥55%; ECOG PS score 0-2, no history of cardiac disease. The following assessments were carried out at baseline, after Epirubucin treatment, at each TZB treatment and every 3 months during 1 year follow-up: ECOG PS score, conventional echocardiography and 2D/3D ST parameters (circumferential and longitudinal S and SR, LV torsion) Results: At Dec 2012, 38 patients (mean ± SD age 51±10 yo) have been enrolled. A significant reduction of the longitudinal peak of SR (0.71±0.16 s-1 vs 0.81±0.14 s-1; p<0.05) was found after Epi treatment, while a significant increase of circumferential function (1.03±0.31 s-1 vs 0.71±0.13 s-1; p<0.01) was evidenced. From the third dose of TZB a maked reduction of the circumferential function (0.69±0.18 s-1 vs 1.03±0.31 s-1; p<0.01) and of LV rotation (15.26±5.38 vs 22.88±6.41; p<0.001) was found, while no further reduction in the longitudinal function was determined. Conclusions: The aim of the study was that to ascertain the amount, timing and type of the pre-clinical cardiac dysfunction induced by TZB when administered after anthracyclines. We evidenced that after anthracyclines longitudinal function is impaired while a compensatory increase of LV circumferential function and of LV torsion is present. After TZB we showed mostly a toxicity of mid and sub epicardial fibres, responsible mainly for the circumferential function and of the torsion of the left ventricle. These effects could be related to the higher toxicity of TZB on the hyperactive myocardial fibres after Epi treatment. Follow up data will show if this mid and sub epicardial myocardial impairment will persist over time.

GW24-e3507 Acute Effects of Rotation and Twist at Different Cardiac Pacing Sites Using Speckle Tracking Imaging

ObjectivesDifferent cardiac site pacing may lead to different changes in the mechanics of left ventricular (LV) function, but how it affects LV rotation and twist is unknown. In this study,...

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

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. 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). 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). 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.

Assessment of left ventricular rotation in rheumatic mitral stenosis patients by velocity vector imaging

Objective To assess the regional left ventricular (LV) rotation motion in the patients with rheumatic mitral stenosis (MS) with velocity vector imaging (VVI).Methods This study included 38 patients with isolated MS (mild,moderate and severe) and 55 healthy control subjects.Short-axis parasternal views at the basal and apical level of LV were taken.Peak value of rotation angle and rotation velocity,as well as time to peak value were measured by VVI workplace offline respectively.Results ①In the healthy control subjects LV rotates clockwisely at the base and counterclockwisely at the apex,the same as the patients with MS.② In th patients with MS,rotaion angle and rotation velocity were significantly reduced at the apical level(P ＜0.001),rotation velocity were significantly reduced at some segments of basal level (anterior,lateral,septal) (P ＜ 0.05).③Compared with the healthy control,the difference of time to peak roation angle between base and apex was significantly longer in patients with MS (P ＜0.05).④ There were no significant differences among mild,moderate and severe MS (P ＞0.05).Conclusions The patients with MS may suffer from systolic dysfunctin even in the early stage identified by the alteration of LV rotation motion,which is independent of the hemodynamic severity of MS. Key words: Echocardiography; Rheumatic heart disease; Mitral valve stenosis; Ventricular function,left ; Velocity vector imaging

Study of early recovery of left ventricular rotation and torsion after percutaneous coronary intervention using two dimensional speckle tracking echocardiography

Objective To evaluate left ventricular rotation and torsion and its early recovery after percutaneous coronary intervention (PCI) in patients with coronary heart disease and normal left ventricular ejection fraction (LVEF) using two dimensional speckle tracking echocardiography.Methods Twenty three consecutive patients with coronary heart disease and normal LVEF were divided into group B (with coronary stenosis ＜70％) and group C (with coronary stenosis ＞70％ and with PCI).Along with 11 healthy controls(group A),indices including basal rotation (BR),apical rotation (AR),left ventricular torsion (LVT) and normalized time to peak were compared among groups,correlative analysis was made between LVT and each indices mentioned above,indices of group C before and 24 hours after PCI were compared.Results AR,LVT in group B and C reduced relative to group A (P ＜0.05),meanwhile time to peak of BR in group C shortened relative to other groups.BR,AR and normalized time to peak of BR were correlated to LVT respectively.BR and LVT in group C increased after PCI(P ＜0.05).Conclusions AR was sensitive to ischemia,the reduction of time to peak of BR in group C might be restriction and compensation.Sensitive to early recovery of left ventricular function after reperfusion,BR could be a predictive index of early effect of percutaneous coronary intervention. Key words: Echocardiography; Coronary disease; Stents; Ventricular function,left; Speckle tracking imaging

Left ventricular twist in left ventricular noncompaction

Left ventricular (LV) twist is an important component of systolic function. The effect of abnormal LV twist on adverse remodelling of the heart in left ventricular noncompaction (LVNC) is unknown. This study used speckle-tracking echocardiography to evaluate LV twist in patients with LVNC and determine whether abnormal LV twist is associated with more adverse LV remodelling. Clinical, echocardiographic, and myocardial deformation characteristics were prospectively compared between 60 subjects diagnosed with LVNC and 59 age-matched healthy controls. Net instantaneous twist was defined as: peak apical rotation minus isochronous basal rotation. Normal rotation during systole was defined based on the 2010 ASE/EAE consensus document. Rigid body rotation (RBR) was determined present if the apex and base moved in the same direction during ejection. Rigid body rotation was found in 32 (53.3%) subjects with LVNC. The 28 subjects with LVNC and normal LV rotation had diminished apical rotation, basal rotation, and net twist compared with normal controls (P < 0.0001). Patients with LVNC and RBR had worse NYHA functional status (P < 0.0001), but similar echocardiographic indices of remodelling, ejection fraction, and strain parameters as those with LVNC and normal LV rotation. Left ventricular twist is diminished in subjects with LVNC and normal LV rotation. Rigid body rotation occurs in 53.3% of subjects with LVNC and is not associated with more adverse remodelling than subjects with LVNC and normal LV rotation.

The effect of myocardial fibrosis on left ventricular torsion and twist in patients with non-ischemic dilated cardiomyopathy

Left ventricular (LV) rotation, twist, and torsion are important aspects of the cardiac performance. Myocardial fibrosis can be identified as the late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR). In this study, we investigated the association between myocardial fibrosis and LV rotational parameters in patients with nonischemic dilated cardiomyopathy (NDC). Twenty-two NDC patients were enrolled. LV dimensions, volumes and ejection fraction (EF) were measured, conventional tissue Doppler imaging data was acquired. Speckle tracking imaging was performed to measure LV deformation, LV rotational parameters. Blood samples were obtained for NT-proBNP. Late gadolinium enhanced cardiac magnetic resonance (LGE-CMR) was used to assess cardiac fibrosis index. Myocardial deformation was similar between LGE+ and LGE- groups. LGE+patients have significantly higher basal and lower apical systolic rotation, lower twist and torsion when compared to LGE- patients. However, untwisting rate was similar between the groups. Torsion was significantly correlated with LVEF and MR-index. Patients with reversed apical systolic rotation had significantly greater NT-proBNP values, basal systolic rotation and significantly lower apical systolic rotation, torsion, and MR-index. Cardiac fibrosis index is closely related with myocardial torsion and LV systolic function and may be used for the evaluation of cardiac condition. Reversed apical systolicrotation indicated more extensive cardiac fibrosis as it may reflect severe LV dyssynchrony andpoor LV performance.

Effect of Pharmacologic Increases in Afterload on Left Ventricular Rotation and Strain in a Rabbit Model

Assessment of left ventricular rotational mechanics and myocardial deformation may provide new insight into both systolic and diastolic function. However, the effects of increasing afterload on these measures of cardiac function are poorly understood. The aim of this study was to identify the changes in left ventricular function and rotational mechanics during increasing pharmacologic afterload. In 14 anesthetized rabbits, two-dimensional speckle-tracking echocardiographic images and left ventricular pressure-volume loops were acquired at baseline and during norepinephrine, phenylephrine, and vasopressin infusion at increasing doses. Maximal ventricular elastance, arterial elastance, ventricular-arterial coupling, dP/dt, the time constant of relaxation, and other hemodynamic parameters were determined. An increase in dP/dtmax with norepinephrine and phenylephrine and a decrease with vasopressin at escalating doses were detected. Ventricular-arterial coupling was preserved with norepinephrine and phenylephrine but decreased with vasopressin (P < .05). Apical rotation, rotational rate, and strain were preserved during the norepinephrine and phenylephrine infusions but were reduced with vasopressin (P < .05). Apical rotation and circumferential strain were significantly correlated with both ventricular-arterial coupling (r = 0.84 and r = 0.81) and dP/dtmax (r = -0.81 and r = -0.77). High-dose vasopressin decreased the diastolic time constant of relaxation and dP/dtmin while reducing apical untwisting rate. Pharmacologic increases in afterload with vasopressin resulted in greater derangements in ventricular-arterial coupling and cardiac performance compared with norepinephrine and phenylephrine. Rotation and strain correlated well with invasively determined measures and can be used to assess afterload-induced alteration in cardiac function.

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

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

Feasibility and Observer Reproducibility of Speckle Tracking Echocardiography in Congenital Heart Disease Patients

The twisting motion of the heart has an important role in the function of the left ventricle. Speckle tracking echocardiography is able to quantify left ventricular (LV) rotation and twist. So far this new technique has not been used in congenital heart disease patients. The aim of our study was to investigate the feasibility and the intra- and inter-observer reproducibility of LV rotation parameters in adult patients with congenital heart disease. The study population consisted of 66 consecutive patients seen in the outpatient clinic (67% male, mean age 31±7.7years, NYHA class 1±0.3) with a variety of congenital heart disease. First, feasibility was assessed in all patients. Intra- and inter-observer reproducibility was assessed for the patients in which speckle tracking echocardiography was feasible. Adequate image quality, for performing speckle echocardiography, was found in 80% of patients. The bias for the intra-observer reproducibility of the LV twist was 0.0°, with 95% limits of agreement of -2.5° and 2.5° and for interobserver reproducibility the bias was 0.0°, with 95% limits of agreement of -3.0° and 3.0°. Intra- and inter-observer measurements showed a strong correlation (0.86 and 0.79, respectively). Also a good repeatability was seen. The mean time to complete full analysis per subject for the first and second measurement was 9 and 5minutes, respectively. Speckle tracking echocardiography is feasible in 80% of adult patients with congenital heart disease and shows excellent intra- and inter-observer reproducibility.

3-dimensional speckle tracking echocardiography for left ventricular rotation and twist in patients with hypertension

To analyze the characteristics of left ventricular rotation and twist in patients with essential hypertension (EH) of different left ventricular configurations by 3-dimensional speckle tracking echocardiography (3D-STE). A total of 106 EH patients were divided into 4 groups: a left ventricular normal configuration (LVN) group (n=30), a concentric remodeling (CCR) group (n=31), a concentric hypertrophy (CCH) group (n=29), an eccentric hypertrophy (ECH) group (n=16), and a control group of 30 healthy subjects. The parameters of LVEF, peak basal rotation (Prot-B), peak apical rotation (Prot-A), left ventricular peak apical rotation (LV-rot), and left ventricular peak apical twist (LV-tw) were compared. The left ventricular mass index in the EH groups, which kept increasing, was higher than that in the normal control group (P<0.05). Compared with the normal control group, LVN and ECH group, the left ventricular posterior wall thickness, interventricular septum at end-diastole, and relative wall thickness significantly increased in the CCH and CCR group (P<0.05). LVEF showed no significant difference among the normal control, LVN, CCR and CCH group (P>0.05), but LVEF was lower in the ECH group than in other groups (P<0.05). Compared with the normal control group, Prot-B, Prot-A, LVrot and LVtw were significantly higher in the LVN, CCR and CCH group (P<0.05), but decreased in the ECH group (P<0.05). 3D-STE can evaluate the left ventricular rotation and twist in EH patients with different configurations, and reflect changes in the left ventricular systolic function in EH of different configurations.

Ventricular mechanics in patients with aortic valve disease: longitudinal, radial, and circumferential components

Reduced long-axis shortening despite enhanced global function has been reported in aortic stenosis. We sought to improve the understanding of this phenomenon using multi-dimensional strain analysis in conjunction with the evaluation of left ventricular rotation and twist - ventricular torsion - using tissue Doppler techniques. A total of 57 patients with variable severity of aortic stenosis, aortic regurgitation, or mixed aortic valve disease, subdivided into six groups, were studied. Ventricular morphology was assessed using long-axis/short-axis and mass/volume ratios, afterload using end-systolic meridional wall stress, and global performance using ejection fraction. The circumferential and longitudinal strain was measured from two-dimensional images, and left ventricular rotation and twist were estimated as the difference in rotation between the base and apex of the ventricle. Aortic stenosis was associated with higher mass/volume, ejection fraction, circumferential strain and left ventricular rotation and twist, significantly lower end-systolic wall stress, and a trend towards lower longitudinal strain compared with normal. Myocardial mechanics in aortic regurgitation were normal despite ventricular dilation. Mixed aortic valve disease showed findings similar to aortic stenosis. Left ventricular rotation and twist correlated with midwall circumferential strain (r = 0.62 and p < 0.0001), endocardial circumferential strain (r = 0.61 and p < 0.0001), and end-systolic wall stress (r = 0.48 and p < 0.0001), but not with longitudinal strain (r = 0.18 and p > 0.05). Myocardial mechanics are normal in patients with aortic regurgitation, independent of abnormalities in cardiac geometry. Conversely, in aortic stenosis and mixed aortic valve disease, significant alterations in the patterns of fibre shortening are found. The effects of stenosis on cardiac function seem to dominate the effect of ventricular remodelling.

Assessment of Subendocardial Contractile Function in Aortic Stenosis: A Study Using Speckle Tracking Echocardiography

Angina and an electrocardiographic strain pattern are potential manifestations of subendocardial ischemia in aortic stenosis (AS). Left ventricular (LV) twist is known to increase proportionally to the severity of AS, which may be a result of loss of the inhibiting effect of the subendocardial fibers due to subendocardial dysfunction. It has also been shown that the ratio of LV twist to circumferential shortening of the endocardium (twist-to-shortening ratio [TSR]) is a reliable parameter of subendocardial dysfunction. The aim of this study was to investigate whether these markers are increased in AS patients with angina and/or electrocardiographic strain. The study comprised 60 AS patients with an aortic valve area <2.0cm(2) and LV ejection fraction >50%, and 30 healthy-for age and gender matched-control subjects. LV rotation parameters were determined by speckle tracking echocardiography. Comparison of patients without angina and strain (n=22), with either angina or strain (n=28), and with both angina and strain (n=8), showed highest peak systolic LV apical rotation, peak systolic LV twist, and TSR, in patients with more signs of subendocardial ischemia. In a multivariate linear regression model, only severity of AS and the presence of angina and/or strain could be identified as independent predictors of peak systolic LV twist and TSR. Peak systolic LV twist and TSR are increased in AS patients and related to the severity of AS and symptoms (angina) or electrocardiographic signs (strain) compatible with subendocardial ischemia.

Effect of stellate ganglia stimulation on global and regional left ventricular function as assessed by speckle tracking echocardiography

Left ventricular (LV) twist mechanics and regional strain during cardiac sympathetic efferent activation are poorly understood. The purpose of this study was to compare the effects of left stellate ganglia (LSG) and right stellate ganglia (RSG) stimulation on cardiac twist/untiwst mechanics and regional strain. In nine pigs, echocardiographic imaging and LV pressure-volume measurements were performed before and during unilateral and bilateral stellate ganglion stimulation. LSG and RSG stimulation significantly augmented LV end-systolic pressure by 24% and 22% (P < 0.01), maximal rate of LV pressure change by 167% and 165% (P < 0.01), and time constant of LV relaxation by 20% and 12% (P < 0.01), respectively. RSG stimulation resulted in a greater chronotropic response than LSG stimulation (RSG: 68% vs. LSG: 12%, P < 0.01). Both LSG and RSG stimulation significantly increased global epicardial and endocardial LV rotation and diastolic untwisting rate and reduced the time to peak rotation (P < 0.05). However, LSG stimulation predominantly increased radial and circumferential strain in the LV inferoseptal, inferior, posterior, and lateral regions, whereas RSG stimulation primarily increased radial and circumferential strain in the anteroseptal, anterior, and lateral LV regions. Stimulation of both stellate ganglia led to a uniform increase in all LV segments. Our data suggest that LSG and RSG stimulation lead to a global increase in LV twist, driven by distinct regional strain heterogeneity that may result from myocardial innervation from the LSG and RSG. These findings provide a better understanding of the global and regional functional consequences of regional myocardial innervation from the LSG and RSG.

Ventricular Torsion: Research Tool or Novel Clinical Indicator?

Ventricular Torsion: Research Tool or Novel Clinical Indicator?

Left Ventricular Rotation and Twist Assessed by Four‐Dimensional Speckle Tracking Echocardiography in Healthy Subjects and Pathological Remodeling: a Single Center Experience

Left ventricular (LV) twist represents a main aspect of ejection. It is defined as the difference between the apical and basal rotation and can be assessed by speckle tracking echocardiography (STE). Twist may be underestimated when assessed by two-dimensional-echocardiography due to the difficulty of identifying the real apex. Aim of this study was to evaluate the LV twist by means of three-dimensional (3D)-STE and verify if the inclusion of the apex can modify the assessment of the global twist. LV volume acquisition with a fully sampled matrix array transducer was performed in 30 healthy subjects and 79 patients with cardiomyopathy secondary to different etiologies. Thirty-nine patients had a LV ejection fraction (EF) ≥50% (Group A), 16 showed an EF between 40 and 50% (Group B), and 24 patients had an EF ≤40%(Group C). LV rotation was assessed by 3D-STE at basal, medium, apical, and apical-cap levels. Twist was computed considering the apex either at the apical level (Twist(Api) ) or at the apical-cap level (Twist(AC) ). LV rotation resulted to be progressively higher from base to apical-cap (P < 0.0001) with a significant difference between the apex and the apical-cap level (6.20 ± 3.90° vs. 10.23 ± 7.52°; P < 0.001). Such a difference was constantly found in all Groups (P < 0.01 for Group A, P < 0.05 for Group B and C). Twist(Api) was also significantly lower than Twist(AC) both in the overall population (6.2 ± 3.89° vs. 10.23 ± 7.51°; P < 0.001) and in the different subgroups ( 9.61 ± 3.39° vs. 13.75 ± 6.51°; Group A: 10.49 ± 4.77° vs. 16.37 ± 8.49°; Group B: 6.67 ± 3.44° vs. 9.14 ± 5.55°; Group C: 33 ± 2.62° vs. 5.26 ± 3.74°; P < 0.05 for all the comparisons). Identification and inclusion of apical-cap is relevant for twist assessment and can be carried out efficiently by 3D-STE. The inclusion of the true apex in the calculation significantly affects the analysis of twist both in normal individuals and patients with different myocardial diseases.

Abstract 9351: Left Ventricular Torsion is Preload Dependent. A Study in Healty Volunteers After Blood Donation

Introduction: Left ventricular (LV) rotation plays an important role in LV contraction and relaxation. Hypothesis: Aim of this study is to investigate preload effect on LV torsion in normal volunteers of blood donation. Methods and Results: LV end-diastolic volume, LV apical and basal rotation, peak systolic LV Torsion were measured by speckle-tracking echocardiography in normal volunteers (n=26) before and after 450ml blood donation.Blood donation led to a significant decrease in end-diastolic LV internal diameter (48.7 + 0.4 versus 46.4+0.4 mm; P&lt;0.001) and cardiac output (6.2 + 1.0 versus 5.1+ 0.7 L/min; P&lt;0.001). There was a significant decrease in the magnitude of peak systolic apical rotation (4.4 +1.9° versus 2.9 + 1.5°; P&lt;0.001) but no change in basal rotation (2.6 +1.4° versus 2.7+ 1.6°; P=0.81). Peak systolic LV Torsion decreased after blood donation (6.9 +1.9 ° versus 5.7+2.1°; P=0.028). Conclusions: LV apical and peak systolic LV torsion are preload dependent. Preload changes should be considered when interpreting LV torsion

Abstract 8980: Investigating Left Ventricular Torsion with 4-Dimensional Echocardiography

Background: We investigated the relationship between left ventricular (LV) torsion, strain and stroke volume (SV) using a new 4-dimensional (4D) echocardiography strain and mechanics program developed by Siemens. Methods: We used an in vitro rotation model capable of producing torsion and longitudinal strain in 3 freshly harvested pig hearts, which were secured on a pump phantom in a water bath with the apex fixed and the base rotated 0°, 10° and 20° at SVs of 40, 50, 60 and 70 ml. 4D image loops were obtained on a Siemens Acuson SC2000 ultrasound system using a 4Z1C matrix probe. Results: As degrees of rotation increased, computed apical and basal rotation increased accordingly. There was no strong correlation between computed rotation and SV. The Siemens 3D mechanics program computed slight degrees of rotation at both the apical and basal levels, even when the phantom control system was set to 0° rotation. Conclusions: The apparent rotation measured when the rotator was set to 0° supports the hypothesis that rotation is intrinsic and originates from the helical orientation of the myocardial fibers. The 4D program tracked increasing LV rotation extremely accurately in our study.

STUDY OF LEFT VENTRICULAR ROTATION AND TORSION IN HYPERTHYROID BY SPECKLE TRACKING IMAGING

ObjectivesQuantitative analysis of hyperthyroidism in patients with left ventricular rotation and torsion motion by speckle tracking imaging (STI) to explore the hyperthyroidism in patients with left ventricular systolic function.MethodsSelect the...

STUDY OF LEFT VENTRICULAR ROTATION AND TORSION IN HYPERTHYROID BY SPECKLE TRACKING IMAGING

ObjectivesQuantitative analysis of hyperthyroidism in patients with left ventricular rotation and torsion motion by speckle tracking imaging (STI) to explore the hyperthyroidism in patients with left ventricular systolic function.MethodsSelect the...