Myocardial Strain Rate Research Articles

Comparative Feasibility of Myocardial Velocity and Strain Measurements Using 2 Different Methods With Transesophageal Echocardiography During Cardiac Surgery

To assess the feasibility and correlation between tissue Doppler and speckle tracking imaging when measuring myocardial velocity, strain, and strain rate with transesophageal echocardiography. A prospective, observational study. An academic tertiary-referral hospital. Patients undergoing elective heart surgery. None. Velocity, strain, and strain rate were measured using both techniques in the inferior and anterior walls in transgastric views for radial motion and in the lateral, septal, anterior, and inferior walls in midesophageal views for longitudinal motion. Nineteen patients and 304 myocardial segments were studied. Overall, tissue Doppler was found to be more successful than speckle tracking in measuring myocardial velocity, whereas strain and strain rate measurements were achieved with comparable success using either method. Tissue Doppler was more successful than speckle tracking for radial cardiac motion, and the highest success rates were achieved with this method (93.4% v 59.2% for velocity, p < 0.001; 78.9% v 59.2% for strain, p = 0.01; and 73.7% v 59.2% for strain rate, p = 0.09). Good correlation between tissue Doppler and speckle tracking was shown in 4 myocardial segments: radial midinferior, radial basal inferior, radial basal anterior, and longitudinal basal septum (R = 0.6-0.82, p < 0.05). The correlation between tissue Doppler and speckle tracking with transesophageal echocardiography appears valid when predominantly confined to segments moving in a radial direction adjacent to the ultrasound transducer. Tissue Doppler echocardiography of radial cardiac motion appears to be the most feasible technique of measuring myocardial velocity, strain, and strain rate during cardiac surgery.

Left ventricular remodeling after myocardial infarction impairs early diastolic, but not systolic, function in the radial direction in the remote normal region

It is acknowledged that expansion of the remote normal region of the left ventricle causes remodeling after myocardial infarction (MI). However, the characteristics of that region have not been fully elucidated. We studied 13 patients with atypical chest pain (controls) and 15 patients with a prior anterior MI who underwent cardiac catheterization. With Doppler strain imaging, we measured the peak radial myocardial systolic strain and peak radial early diastolic strain rate at the posterior wall of the left ventricle. None of the patients with atypical chest pain exhibited significant stenosis of the three major coronary arteries or left ventricular (LV) wall motion abnormality in cardiac catheterization. The patients with a prior anterior MI had single anterior descending artery disease without wall motion abnormality in the LV inferoposterior wall. LV ejection fraction and the LV relaxation time constant were also measured. The LV ejection fraction was significantly smaller in patients with a prior MI compared to controls. The peak radial systolic strain in the LV posterior wall was not significantly different between the patients with a prior MI and controls (125±49 vs. 122±29%). In contrast, the peak radial early diastolic strain rate in the same area was significantly lower in the patients with a prior MI than in controls (-7.4±2.7 vs. -13.2±4.0s(-1), p<0.001). Peak early diastolic radial strain rate was significantly correlated with the LV relaxation time constant in all patients (r=0.69, p<0.001). LV remodeling after an MI impairs local early diastolic myocardial function in the remote normal region and it is related to global LV diastolic dysfunction.

Independent Predictors of Survival in Primary Systemic (AL) Amyloidosis, Including Cardiac Biomarkers and Left Ventricular Strain Imaging: An Observational Cohort Study

The prognostic value of Doppler myocardial imaging, including myocardial velocity imaging, strain, and strain rate imaging, in patients with primary (AL) amyloidosis is uncertain. The aim of this longitudinal study was to identify independent predictors of survival, comparing clinical data, hematologic and cardiac biomarkers, and standard echocardiographic and Doppler myocardial imaging measures in a cohort of patients with AL amyloidosis. A total of 249 consecutive patients with AL amyloidosis were prospectively enrolled. The primary end point was all-cause mortality, and during a median follow-up period of 18 months, 75 patients (30%) died. Clinical and electrocardiographic data, biomarkers (brain natriuretic peptide and cardiac troponin T) and standard echocardiographic and longitudinal systolic and diastolic Doppler myocardial imaging measurements for 16 left ventricular segments were tested as potential independent predictors of survival. Age (hazard ratio [HR], 1.03; P = .03), New York Heart Association class III or IV (HR, 2.47; P = .01), the presence of pleural effusion (HR, 1.79; P = .08), brain natriuretic peptide level (HR, 1.29; P = .01), ejection time (HR, 0.99; P = .13), and peak longitudinal systolic strain of the basal anteroseptal segment (HR, 1.05; P = .02) were independent predictors in the final model. Multivariate survival analysis identified independent predictors of clinical outcome in patients with AL amyloidosis: New York Heart Association class III or IV, presence of pleural effusion, brain natriuretic peptide level > 493 pg/mL, ejection time < 273 ms, and peak longitudinal systolic basal anteroseptal strain less negative than or equal to -7.5% defined a high-risk group of patients.

Longitudinal Tissue Velocity and Deformation Imaging in Inferobasal Left Ventricular Aneurysm

Longitudinal myocardial tissue velocity imaging (TVI) and strain rate imaging (SRI) quantify regional myocardial function. We aimed to measure TVI and SRI indices for inferobasal aneurysmal segments by echocardiography at rest. Sixteen patients with inferobasal left ventricular (LV) aneurysm, LV ejection fraction (EF) ≤50%, and 14 normal coronaries with normal echocardiography (control group) were studied. In SRI, peak systolic strain (ST), strain rate (SR), and pattern of strain curves and in TVI, peak systolic inward motion (Sm) were evaluated all at rest. Ascending curve means systolic expansion and descending means shortening. LVEF was significantly lower in the patient group. Mean ST, SR, and Sm of inferobasal segment showed significant difference between patient and control groups; for ST: 1.45 ± 7.18% versus -17.64 ± 7.45%, P < 0.0001; SR: -0.25 ± 0.26 versus -1.44 ± 0.64 sec(-1) , P < 0.0001; and Sm: 3.85 ± 1.26 versus 5.56 ± 1.28 cm/sec, P = 0.006, respectively. All inferobasal aneurysmal segments had ascending curve while normal segments showed a descending curve. In patient group, aneurysmal segments had significantly reduced ST and SR compared to normal segments. Normal functioning segments of patients showed significant reduction of ST and SR compared to normal LV segments in control subjects. The range of SR and ST for inferobasal aneurysmal segments did not overlap with that of the normal segments (-0.60, 0.19 and -3.00, -0.80 sec(-1) for SR, and -8.30, 23.30 and -35.30, -10.00% for ST, respectively). SRI indices were significantly reduced in inferobasal aneurysmal segment in comparison with either the same segment in normal subjects or normal functioning segments in the same patients. SR and ST may be superior to Sm in the evaluation of inferobasal aneurysmal segments.

Left ventricular myocardial strain and strain rates in sub-endocardial and sub-epicardial layers before and after a marathon

We assessed myocardial deformation in sub-endocardial and sub-epicardial layers of the left ventricle (LV) wall before and after running a marathon. Echocardiography scans were performed on 14 male, non-elite runners (mean +/- SD; age 32 +/- 10 years) who completed the 42.2-km London marathon. Para-sternal short axis and apical four-chamber views were recorded for off-line analysis. Peak longitudinal, radial and circumferential strains, peak systolic and early diastolic strain rates were recorded. Circumferential rotation in basal and apical LV scans was used to calculate torsion. Pre-race strain and strain rates were generally greater in the sub-endocardial layer of the LV wall. After race completion, a mixed pattern of change was observed with a reduction in sub-epicardial radial strain (32.6 +/- 12.5 to 20.3 +/- 9.6%; P < 0.01) and sub-endocardial circumferential strain (-26.9 +/- 3.6 to -23.7 +/- 4.1%; P < 0.01) at the apex. Rotation was not altered at either the apical or basal levels and thus torsion was not changed in either the sub-endocardium (6.72 +/- 3.46 degrees to 5.67 +/- 4.98 degrees) or the sub-epicardium (3.48 +/- 2.68 degrees to 3.01 +/- 3.23 degrees). Strain rates and rotation rates were only sporadically altered post-race. There are differences in deformation characteristics between the sub-endocardium and sub-epicardium at baseline, and the limited changes observed post-race were not specific to any region or depth of the LV wall.

Sub-clinical left and right ventricular dysfunction in patients with COPD

Cardiovascular manifestations in COPD include increased arterial stiffness, ischaemic heart disease, chronic heart failure and cor pulmonale. We hypothesised that sub-clinical right (RV) and left ventricular (LV) dysfunction occurs in patients with COPD, related to the severity of airflow obstruction, arterial stiffness and systemic inflammation. Thirty six patients and 14 controls, all free of overt cardiovascular disease underwent tissue Doppler echocardiography, spirometry, measurement of aortic pulse wave velocity (PWV) and venous sampling for inflammatory markers. Mean LV myocardial strain and strain rate were less in patients than controls, p<0.05. LV isovolumic relaxation time (IVRT) was prolonged in patients (125+/-15.2ms) compared with controls (98.2+/-21.1ms), p<0.01, indicating LV diastolic dysfunction. The RV free wall strain and strain rate were less in patients than controls, both p<0.05, indicating RV systolic dysfunction. Patients had sub-clinical pulmonary arterial hypertension with a greater RV myocardial relaxation time and Tei index, both p<0.01. Patients with mild airways obstruction had LV and RV dysfunction and evidence of increased RV afterload compared with controls. In multivariate analyses aortic PWV predicted LV IVRT, p<0.01, while FEV(1) predicted RV Tei index and myocardial relaxation time, both p<0.01. Patients with COPD have sub-clinical left ventricular dysfunction related to arterial stiffness, and right ventricular dysfunction related to airways obstruction. Both right and left ventricular dysfunction are present in patients with mild airways obstruction suggesting that cardiac co-morbidities commence early in the development of COPD.

The echocardiographic assessment of the right ventricle: what to do in 2010?

For many years, the echocardiographic quantitative assessment of right ventricular (RV) function has been difficult owing to the complex RV anatomy. Identifying an accurate and reliable echocardiographic parameter for the functional assessment of the RV still remains a challenge. The review presents a summary of the most studied and presently used parameters of RV function, with their reported normal values, as well as advantages and limitations of use. Combinations of these parameters are used in daily clinical practice, each one offering only partial information about the status of the RV. Myocardial velocity and strain rate imaging have promising results in the assessment of RV function. There is hope that novel myocardial deformation parameters and three-dimensional echocardiography-derived parameters may add value to the examination of the RV, but validation studies are still needed.

Evaluation of Subclinical Right Ventricular Dysfunction in Obstructive Sleep Apnea Patients Using Velocity Vector Imaging

The aims of this study were to evaluate subclinical regional right ventricular (RV) dysfunction in newly diagnosed obstructive sleep apnea (OSA) patients without systemic and pulmonary arterial (PA) hypertension, and to correlate OSA severity to RV dysfunction, using both velocity vector imaging (VVI)-derived strain imaging and tissue Doppler imaging (TDI). The OSA group consisted of 27 patients and the control group consisted of 26 healthy participants. All participants underwent 24-h ambulatory blood pressure monitoring. Peak systolic myocardial velocities, strain, and strain rate (SR) were determined at the basal and mid segments of the RV free wall by VVI. Additionally, RV myocardial velocities were assessed by pulsed-wave TDI. Patients with OSA had significantly impaired VVI-derived peak systolic myocardial velocities, strain, and SR (P<0.0001 for all). RV isovolumic acceleration (IVA) was the only TDI-derived parameter that was significantly impaired (P<0.0001). RV IVA (r=-0.512, P<0.0001), RV mid free wall strain (r=0.568, P<0.0001) and SR (r=0.519, P<0.0001) revealed the best correlations with apnea hypopnea index (AHI). Subclinical RV dysfunction is present in OSA patients despite normal systemic and PA pressures. Tissue Doppler-derived RV IVA and VVI-derived RV deformation can accurately recognize and quantify RV function abnormalities in this subgroup of patients.

Effects of Increased Left Ventricular Wall Thickness and Diastolic Dysfunction on Myocardial Mechanics in Cardiac Amyloidosis Utilizing Velocity Vector Imaging

Background: Cardiac amyloidosis is characterized by diastolic dysfunction (DD) and increased wall thickness, but their effects on myocardial mechanics requires characterization. Strain imaging may demonstrate the differential effects on regional myocardial mechanics depending on wall thickness and severity of DD. Methods: 46 patients with cardiac amyloidosis separated into 2 groups by wall thickness (Grp 1< 15mm, Grp 2≥ 15mm) and into 2 classes of diastolic dysfunction (nonrestrictive and restrictive). Using velocity vector imaging (VVI) assessment of 2D images from apical and short axis views, longitudinal, circumferential and radial global and segmental myocardial strain (S) and strain rates (Sr) were determined. Results: Longitudinal S and Sr were significantly reduced in Grp 2 and restrictive DD compared to lesser severities. Similarly, circumferential S, radial S and Sr were significantly reduced only in Grp 2 and in those with restrictive DD.

Multimodality Noninvasive Imaging for Assessment of Congenital Heart Disease

Major advances in the field of pediatric cardiology and cardiac surgery over the last several decades have led to a dramatic improvement in survival rates for most forms of congenital heart disease (CHD). For example, hypoplastic left heart syndrome, a previously lethal defect, now has early survival rates up to 90% at major centers.1 These improved outcomes have produced a growing population of survivors with complex CHD who are now reaching adulthood (Figure 1). During this period, improvements in surgical and medical treatments have been accompanied by developments in diagnostic modalities. Echocardiography has replaced catheterization as the primary diagnostic modality, and it is now uncommon for newborn infants to undergo catheterization for purely diagnostic purposes. Although echocardiography remains the bedrock of noninvasive cardiac imaging, the array of diagnostic modalities and techniques available continue to grow and this has spawned the specialty of “noninvasive cardiac imaging” and the need for the “cardiac imager” to be adept in all the different modalities. Figure 1. Percentage of patients under the age of 1 year (grey bars) and over the age of 18 years (black bars) undergoing echocardiography at Children’s Hospital Boston from 1983 through 2006. Note the reverse trends of these age groups reflecting the steady increase in the proportion of adult patients with congenital heart disease. Although the absolute number of infants undergoing echocardiography during this time period has increased, their proportion has steadily declined. Echocardiography, cardiac magnetic resonance (CMR), and cardiac computed tomography (CCT) are the primary modalities used for noninvasive cardiac imaging in patients with CHD. Nuclear scintigraphy is used in selected circumstances. The Table summarizes the strengths and weaknesses of each modality. Figure 2 shows temporal trends in utilization for the various noninvasive cardiac imaging techniques at our center. It is clear that echocardiography is the most frequently …

Speckle myocardial imaging modalities for early detection of myocardial impairment in isolated left ventricular non-compaction

ObjectiveTo examine the hypothesis that speckle myocardial imaging (SMI) modalities, including longitudinal, radial and circumferential systolic (s) and diastolic (d) myocardial velocity imaging, displacement (D), strain rate (SR) and strain...

Ventricular Actuation Improves Systolic and Diastolic Myocardial Function in the Small Failing Heart

Direct mechanical ventricular actuation (DMVA) provides non-blood contacting augmentation of ventricular function. The device has promise for supporting the pediatric heart. The purpose of this study was to assess DMVA's effect in a small animal model of heart failure. Anesthetized rabbits (n = 6) underwent sternotomy and were instrumented for hemodynamic monitoring. A 10-MHz ultrasound probe was used for transesophageal echocardiography imaging. Heart failure (cardiac output <50% baseline) was induced with esmolol. Phenylephrine was titrated to maintain baseline mean arterial pressure. Transesophageal echocardiography imaging was acquired at baseline, heart failure, and subsequent DMVA support for 2 hours. Image analysis was used to derive ejection fraction, cardiac output, and stroke work as measures of left ventricular function. Speckle tracking software was used to derive myocardial strain rates as load-independent measures of left ventricular myocardial function. Mean ejection fraction was significantly increased during DMVA support (0.585 +/- 0.035) versus failure (0.215 +/- 0.014; p < 0.001). Peak global left ventricular systolic and diastolic strain rates (1/second) were significantly increased during DMVA (-2.85 +/- 0.33 and 2.92 +/- 0.37) versus failure (-1.69 +/- 0.11 and 1.99 +/- 0.14; p < 0.001 and 0.004, respectively). Peak strain rates during DMVA in the failing heart were similar to baseline. Direct mechanical ventricular actuation augments both systolic and diastolic left ventricular pump function. Diastolic augmentation distinguishes the device from other direct cardiac compression methods. This study demonstrated that DMVA in the small-sized, failing heart improves both systolic and diastolic myocardial function, which has favorable implications for left ventricular recovery. Direct mechanical ventricular actuation's salutary effects can be provided to the failing pediatric heart without complications of blood contact.

Velocity Vector Imaging in the Measurement of Left Ventricular Twist Mechanics: Head-to-Head One Way Comparison Between Speckle Tracking Echocardiography and Velocity Vector Imaging

Velocity vector imaging (VVI) is based on myocardial feature tracking, which incorporates speckle and endocardial border tracking and allows myocardial strains, strain rates, and velocities to be quantified. However, the accuracies of VVI-derived left ventricular rotation-associated values have not been validated, and the aim of this study was thus to perform a head-to-head comparison of twist-related values determined by VVI and speckle-tracking echocardiography (STE). Thirty-five patients with a wide spectrum of cardiac pathologies and 19 healthy subjects (a total of 54 subjects) were enrolled. Apical and basal short-axis images were obtained using GE Vivid 7 scanners at frame rates of 80 to 100 frames/s. Left ventricular rotation-related parameters were first obtained using EchoPAC version 7.0.1. For comparison purposes, the same basal and apical short-axis images were converted into uncompressed Digital Imaging and Communications in Medicine format and subsequently analyzed using Syngo version 3.0, which uses a VVI tracking algorithm. Basal and apical peak rotation and peak twist determined using STE and VVI were well correlated (r = 0.80, P < .001, r = 0.87, P < .001, and r = 0.90, P < .001, respectively). With regard to rotation velocities, peak rotation and derotation velocities were moderately correlated at the basal (r = 0.70, P < .001, and r = 0.72, P < .001, respectively) and apical (r = 0.66, P < .001, and r = 0.51, P < .001, respectively) levels. Furthermore, twist and untwist velocities were moderately correlated between the two methods. However, the timings of peak rotation and derotation velocities and twist and untwist velocities were only weakly correlated at the basal and apical levels. VVI is a feasible modality for assessing twist-related parameters. Although VVI agreed well with STE for most of the rotation-related parameters, poor concordance was found between the two methods for a few parameters. It is hypothesized that this discrepancy originates from the different tracking algorithms used. The findings indicate that caution should be exercised when interpreting or comparing twist-related parameters obtained using different echocardiographic devices with proprietary image analyzers.

Evaluation of regional left ventricular longitudinal function in 151 normal fetuses using velocity vector imaging

The purpose of this study was to investigate the clinical value of velocity vector imaging (VVI) in the assessment of normal fetal regional myocardial performance and to establish a normative data set for normal Chinese fetuses. One hundred and fifty-one healthy Chinese fetuses were divided into five groups according to their gestational age. Digital dynamic four-chamber views were collected and analyzed offline. The regional tissue velocity, strain, and strain rate of the interventricular septum and left lateral wall were measured in systole and diastole. Normal systolic and diastolic values for tissue velocity, strain, and strain rate were established. Tissue velocity decreased gradually from the basal segment to the apical segment (P < 0.01), whereas the strain and strain rate were stable among all segments in every group (P > 0.05). Tissue velocity was dependent on gestational age (P < 0.05), whereas strain and strain rate were stable throughout gestation (P > 0.05). VVI is a novel noninvasive tool for quantitative assessment of regional systolic and diastolic function of the fetal heart. Fetal myocardial velocity, strain, and strain rate measurements can be measured easily and reproducibly. This technique is useful for evaluating cardiac function.

Relationship between left atrial deformation and left ventricular diastolic dysfunction in hypertensive patients: A strain rate imaging study

Objectives The present study was designed to investigate the relationship between left atrial (LA) myocardial function and left ventricular (LV) diastolic dysfunction by strain rate imaging. Design and methods 48 essential hypertensive patients and 21 age-matched normal controls were included in the study. LV diastolic dysfunction was classified into no, mild, moderate, and severe groups by using conventional echocardiography and tissue Doppler imaging (TDI). Peak strain rate in the systole (S-Sr), early diastole (E-Sr) and late diastole (A-Sr) was obtained from Doppler derived strain rate imaging to evaluate the LA myocardial deformation. Association between LA myocardial deformation and ratio of mitral peak E velocity to mitral annulus early diastolic velocity (E/Em ratio) was assessed by Pearson correlation coefficient. Results E-Sr was significantly lower in hypertensive patients than normal controls (0.88±0.35 s−1 vs 1.04±0.18 s−1, p=0.028). All the LA myocardial parameters including S-Sr, E-Sr and A-Sr were significantly correlated with E/Em (r=−0.50, −0.528, and −0.360 respectively, all p≤0.015). Similar LA dimension was observed in patients with different degrees of LV diastolic dysfunction while LA myocardial strain rate parameters were all significantly reduced in patients with moderate diastolic dysfunction compared with patients with no diastolic dysfunction (all p<0.001). Compared with patients of no diastolic dysfunction, the mild diastolic dysfunction group had significantly lower E-Sr (0.76±0.34 s−1 vs 1.17±0.40 s−1, p<0.001) but preserved S-Sr and A-Sr. Conclusions Left atrial myocardial deformation is impaired in hypertensive patients, and is closely associated with different degrees of LV diastolic dysfunction. Quantification of the LA early diastolic strain rate rather than LA size may have the potential to predict early LV diastolic dysfunction in hypertensive patients.

Strain analysis in patients with severe aortic stenosis and preserved left ventricular ejection fraction undergoing surgical valve replacement

To evaluate myocardial multidirectional strain and strain rate (S-and-SR) in severe aortic stenosis (AS) patients with preserved left ventricular (LV) ejection fraction (EF), using two-dimensional speckle-tracking strain imaging (2D-STI). The long-term effect of aortic valve replacement (AVR) on S-and-SR was also evaluated. Changes in LV radial, circumferential, and longitudinal S-and-SR were evaluated in 73 severe AS patients (65 +/- 13 years; aortic valve area 0.8 +/- 0.2 cm2) with preserved LVEF (61 +/- 11%), before and 17 months after AVR. Strain and strain rate data were compared with data from 40 controls (20 healthy individuals and 20 patients with LV hypertrophy) matched by age, gender, body surface area, and LVEF. Compared with controls, severe AS patients had significantly decreased values of LV S-and-SR in the radial (33.1 +/- 14.8%, P = 0.2; 1.7 +/- 0.5 s(-1), P = 0.003), circumferential (-15.2 +/- 5.0%, P = 0.001; -0.9 +/- 0.3 s(-1), P < 0.0001), and longitudinal (-14.6 +/- 4.1%, P < 0.0001; -0.8 +/- 0.2 s(-1), P < 0.0001) directions. At 17 months after AVR, LV S-and-SR significantly improved in all the three directions, whereas LVEF remained unchanged (60 +/- 12%, P = 0.7). In severe AS patients, impaired LV S-and-SR existed although LVEF was preserved. After AVR, a significant S-and-SR improvement in all the three directions was observed. These subtle changes in LV contractility can be detected by 2D-STI.

Use of myocardial deformation imaging to detect preclinical myocardial dysfunction before conventional measures in patients undergoing breast cancer treatment with trastuzumab

Trastuzumab prolongs survival in patients with human epidermal growth factor receptor type 2-positive breast cancer. Sequential left ventricular (LV) ejection fraction (EF) assessment has been mandated to detect myocardial dysfunction because of the risk of heart failure with this treatment. Myocardial deformation imaging is a sensitive means of detecting LV dysfunction, but this technique has not been evaluated in patients treated with trastuzumab. The aim of this study was to investigate whether changes in tissue deformation, assessed by myocardial strain and strain rate (SR), are able to identify LV dysfunction earlier than conventional echocardiographic measures in patients treated with trastuzumab. Sequential echocardiograms (n = 152) were performed in 35 female patients (51 +/- 8 years) undergoing trastuzumab therapy for human epidermal growth factor receptor type 2-positive breast cancer. Left ventricular EF was measured by 2- and 3-dimensional (2D and 3D) echocardiography, and myocardial deformation was assessed using tissue Doppler imaging and 2D-based (speckle-tracking) strain and SR. Change over time was compared every 3 months between baseline and 12 months. There was no overall change in 3D-EF, 2D-EF, myocardial E-velocity, or strain. However, there were significant reductions seen in tissue Doppler imaging SR (P < .05), 2D-SR (P < .001), and 2D radial SR (P < .001). A drop > or =1 SD in 2D longitudinal SR was seen in 18 (51%) patients; 13 (37%) had a similar drop in radial SR. Of the 18 patients with reduced longitudinal SR, 3 had a concurrent reduction in EF > or =10%, and another 2 showed a reduction over 20 months follow-up. Myocardial deformation identifies preclinical myocardial dysfunction earlier than conventional measures in women undergoing treatment with trastuzumab for breast cancer.

The role of echocardiography in the assessment of cardiac function in weightlessness—Our experience during parabolic flights

Parabolic flight (PF) elicits changes in hydrostatic pressure gradients, resulting in increase (at 0Gz) or decrease (at 1.8Gz) in cardiac preload. The magnitude of these changes on left ventricular (LV) and atrial (LA) volumes, as well as on myocardial velocities, strain and strain rates, is largely unknown. Using real-time 3D (RT3DE) and Doppler tissue echocardiographic imaging (DTI) during PF in normal subjects in standing position, we showed that both LV and LA volumes were decreased at 1.8Gz and increased at 0Gz by about 20% and 40%, respectively. Previous 2D or M-mode studies underestimated such changes. Also, preload dependence was confirmed for systolic and diastolic velocities, and peak systolic strain, while strain rates were preload independent, probably reflecting intrinsic myocardial properties. Low body negative pressure at -50mmHg applied during 0Gz was effective in restoring 1Gz levels. RT3DE and DTI during PF are feasible, allowing the evaluation of the cardiac function under different loading conditions.

Effects of exercise intervention on myocardial function in type 2 diabetes

Objective:To identify the effects of a 1-year exercise intervention on myocardial dysfunction in patients with type 2 diabetes mellitus (T2DM).Design:Randomised controlled trial, the Diabetes Lifestyle Intervention Study.Setting:University hospital.Patients:223 T2DM patients...

Interpretation of two-dimensional and tissue Doppler-derived strain ( ) and strain rate data: is there a need to normalize for individual variability in left ventricular morphology?

This study examined the relationships between myocardial strain (epsilon) and strain rate (SR) data, derived from both two-dimensional (2D) speckle tracking and tissue Doppler imaging (TDI), and indices of left ventricular (LV) morphology to assess size-(in)dependence of these functional parameters. 2D speckle tracking and TDI echocardiograms were performed in 79 healthy adult male volunteers (age range: 22-76 years). 2D speckle tracking allowed the determination of myocardial epsilon and peak systolic and early diastolic SR in radial, circumferential, and longitudinal planes, whereas TDI provided longitudinal epsilon only. Mean circumferential and radial epsilon and SR were calculated from data collected at six basal myocardial regions, whereas mean longitudinal epsilon and SR derived from both 2D speckle tracking and TDI were calculated from the basal septum and basal lateral walls. Standard 2D echocardiography allowed the assessment of LV morphology including LV length, LV end-diastolic volume, LV end-diastolic diameter, mean wall thickness, and LV mass. The association of myocardial epsilon and SR data with relevant LV morphology indices was determined by adoption of the general, non-linear allometric model (y= ax(b)). The b exponent +/- 95% confidence intervals were reported. The relationships between the measures of LV morphology and myocardial epsilon and SR were highly variable and generally weak. Only two relationships displayed at least a moderate effect size (r > or = 0.30): (i) 2D circumferential peak systolic SR and LV end-diastolic dimension (b = -0.92; -1.35 to 0.5, r = 0.44) and (ii) TDI longitudinal peak systolic SR and LV length (b = -1.39; -2.11 to -0.66, r = 0.41). The empirical relationships derived in this cohort do not support the need to scale myocardial epsilon and SR derived from 2D speckle or TDI for any index of LV morphology.