Evaluation of left ventricular diastolic function by global strain rate imaging in patients with obstructive hypertrophic cardiomyopathy: a simultaneous speckle tracking echocardiography and cardiac catheterization study

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS. In LVEF, mitral E wave deceleration time < 160 ms and pulmonary S-wave < D-wave are also parameters of increased filling pressure. This algorithm does not apply to patients with atrial fibrillation (AF), mitral annulus calcification, > mild mitral valve disease, left bundle branch block, paced rhythm, prosthetic valves, or severe primary pulmonary hypertension.

Echocardiographic Evaluation of Diastolic Function in Special Populations

Left ventricular (LV) diastolic dysfunction results from a combination of impaired relaxation, reduced restoring forces, and increased chamber stiffness. Noninvasive assessment of diastology uses a multiparametric approach involving surrogate markers of increased filling pressures, which include mitral inflow, septal and lateral annular velocities, tricuspid regurgitation velocity, and left atrial volume index. However, these parameters must be used cautiously. This is because the traditional algorithms for evaluating diastolic function and estimation of LV filling pressures (LVFPs), as recommended by the American Society of Echocardiography and European Association of Cardiovascular Imaging 2016 guidelines, do not apply to unique patients with underlying cardiomyopathies, significant valvular disease, conduction abnormalities, arrhythmias, LV assist devices, and heart transplants, which alter the relation between the conventional indexes of diastolic function and LVFP. The purpose of this review is to provide solutions for evaluating LVFP through illustrative examples of these special populations, incorporating supplemental Doppler indexes, such as isovolumic relaxation time, mitral deceleration time, and pulmonary venous flow analysis, as needed to formulate a more comprehensive approach.

Cardiac Multimodality Imaging in Hypertrophic Cardiomyopathy: What to Look for and When to Image

Hypertrophic cardiomyopathy (HCM), now recognized as a common cardiomyopathy of complex genomics and pathophysiology, is defined by the presence of left ventricular hypertrophy of various morphologies and severity, significant hemodynamic consequences, and diverse phenotypic, both structural and clinical, profiles. Advancements in cardiac multimodality imaging, including echocardiography, cardiac magnetic resonance imaging, and cardiac computed tomography, with and without angiography have greatly improved the diagnosis of HCM, and enable precise measurements of cardiac mass, volume, wall thickness, function, and physiology. Multimodality imaging provides comprehensive and complementary information and hasemerged as the bedrock for the diagnosis, clinical assessment, serial monitoring, and sudden cardiac death risk stratification of patients with HCM. This review highlights the role of cardiac multimodality imaging in the modern diagnosis and management of HCM.

The effect of kidney transplantation on left ventricular remodeling and global diastolic strain rate in end-stage renal disease

BACKGROUND

Diastolic dysfunction is an early marker of cardiac pathology in end-stage kidney disease (ESKD) patients. The ratio of transmitral filling velocity (E) to early diastolic strain rate (E/e'sr) is a novel non-invasive marker of early left ventricular (LV) filling pressure obtained using two-dimensional speckle tracking echocardiography (2DSTE).

METHODS

In a prospective cohort of kidney transplant (KTX) recipients with echocardiograms performed pre-transplant we obtained repeat echocardiograms at 6 months following transplant. All echocardiograms were analyzed using 2DSTE where E/e'sr and global longitudinal strain were obtained. Paired tests were used to assess changes to cardiac structure and function following KTX.

RESULTS

A total of 33 patients were included in the study (mean age was 46.6 ± 13.7 years and 42% were males). The primary causes of ESKD in the cohort were glomerular disease (33%), hypertension (30%), and polycystic kidney disease (12%). The median (IQR) time spent on dialysis was 5.4 years [2.9, 7.7 years]. A reverse remodeling of the LV was observed following KTX as LV mass decreased (189.2 ± 57.5 g vs 171.1 ± 56.8 g, P = 0.014). LV filling pressure decreased as assessed by E/e'sr (103.7 ± 51.1 cm vs 72.6 ± 35.5 cm, P = 0.009). E to early diastolic mitral annular tissue velocity (E/e') did not change following KTX (9.9 ± 4.5 vs 10.3 ± 4.1, P = 0.54). Additionally, both LV internal diastolic and systolic diameter decreased significantly.

CONCLUSION

Reverse cardiac remodeling following KTX was observed as improvements in LV mass and LV dimensions. LV filling pressure improved as assessed by E/e'sr decreased following KTX, whereas E/e' did not change.

DeepStrain: A Deep Learning Workflow for the Automated Characterization of Cardiac Mechanics

Myocardial strain analysis from cinematic magnetic resonance imaging (cine-MRI) data provides a more thorough characterization of cardiac mechanics than volumetric parameters such as left-ventricular ejection fraction, but sources of variation including segmentation and motion estimation have limited its wider clinical use. We designed and validated a fast, fully-automatic deep learning (DL) workflow to generate both volumetric parameters and strain measures from cine-MRI data consisting of segmentation and motion estimation convolutional neural networks. The final motion network design, loss function, and associated hyperparameters are the result of a thorough ad hoc implementation that we carefully planned specific for strain quantification, tested, and compared to other potential alternatives. The optimal configuration was trained using healthy and cardiovascular disease (CVD) subjects (n = 150). DL-based volumetric parameters were correlated (>0.98) and without significant bias relative to parameters derived from manual segmentations in 50 healthy and CVD test subjects. Compared to landmarks manually-tracked on tagging-MRI images from 15 healthy subjects, landmark deformation using DL-based motion estimates from paired cine-MRI data resulted in an end-point-error of 2.9 ± 1.5 mm. Measures of end-systolic global strain from these cine-MRI data showed no significant biases relative to a tagging-MRI reference method. On 10 healthy subjects, intraclass correlation coefficient for intra-scanner repeatability was good to excellent (>0.75) for all global measures and most polar map segments. In conclusion, we developed and evaluated the first end-to-end learning-based workflow for automated strain analysis from cine-MRI data to quantitatively characterize cardiac mechanics of healthy and CVD subjects.

3-Year Follow-Up of Radiation-Associated Changes in Diastolic Function by Speckle Tracking Echocardiography

Background

Radiation therapy (RT) results in myocardial changes consisting of diffuse fibrosis, which may result in changes in diastolic function.

Objectives

The aim of this study was to explore RT-associated changes in left ventricular (LV) diastolic function.

Methods

Sixty chemotherapy-naive patients with left-sided, early-stage breast cancer were studied with speckle tracking echocardiography at 3 time points: prior to, immediately after, and 3 years after RT. Global and regional early diastolic strain rate (SRe) were quantified, as were parameters of systolic function.

Results

Regional changes in SRe, particularly the apical and anteroseptal segments, were observed over time and were more evident than global changes. The apical SRe declined from a median of 1.24 (interquartile range: 1.01 to 1.39) s^-1 at baseline to 1.02 (interquartile range: 0.79 to 1.15) s^-1 at 3 years of follow-up (p < 0.001). This decline was associated with the left ventricular maximal radiation dose (β = 0.36, p = 0.007). The global SRe was <1.00 s^-1 (SRe_dep) in 11 (18.3%) patients at baseline, 21 (35%) patients (p = 0.013) post-RT, and 17 (28.3%) patients (p = 0.051) at 3 years. SRe_dep post-RT was independently associated with baseline cardiac abnormalities (odds ratio: 0.26; 95% confidence interval: 0.08 to 0.84; p = 0.025); SRe_dep at 3 years of follow-up was associated with the baseline Charlson comorbidity index (odds ratio: 2.36; 95% confidence interval: 1.17 to 4.77; p = 0.017). Diastolic function abnormalities were evident even in patients with preserved global longitudinal strain at 3 years.

Conclusions

RT resulted in changes in the SRe in the apical and anteroseptal segments over 3 years of follow-up. Changes in SRe apical segments were present even in patients with preserved systolic function and were independently associated with RT dose and cardiovascular comorbidities.

Correlation of left ventricular longitudinal strain and E/e' ratio in primary hypertension patients

Objectives: The aim of this study is to explore and compare the relationships of both global longitudinal strain (GLS) and strain (SR) with E/e' ratio in a population of asymptomatic patients with systemic hypertension.Methods: Retrospectively included 210 cases of essential hypertension patients. Dynamic images were analyzed for left ventricular myocardial systolic global longitudinal strain (GLS), left ventricular longitudinal peak systolic strain rate (SRs), early diastolic peak strain rate (SRe), late diastolic peak strain rate (SRa). According to the 2012 baseline E/e' ratio, the population was divided into three groups, group A (E/e'<8), group B (8 ≤ E/e'≤14), and group C (E/e'>14).Results: Systolic function parameters left ventricular ejection fraction (LVEF) remained at normal rage and no different, but patients with elevated E/e' ratio had significantly lower GLS, lower early diastolic strain rate(SRe), lower ratio of early diastolic strain rate to late diastolic strain rate (SRe/a) and higher E/SRe. Positive relationships were observed between GLS, E/SRe and E/e' ratio, inverse relationships were observed between SRe, SRe/a and E/e' ratio. E/SRe >0.73 had a sensitivity of 87.7% and a specificity of 38.2% for predicting an elevated E/e' ratio (E/e'>14). In multivariable analysis, IVS-e' <7 cm/s showed almost 2.5-fold increased risk for decreased GLS (OR 2.48[95% CI 1.36-4.53]; p = 003).Conclusions: Our current study demonstrated that hypertensive patients with preserved LVEF and elevated E/e' ratio have systolic and diastolic abnormalities in longitudinal directions as detected by speckle imaging. E/SRe correlates well with E/e' and predicted elevated left ventricular filling pressure.

Evaluation of Left Ventricular Diastolic Function by 2-D Speckle Tracking Echocardiography in Patients with Connective Tissue Disease-Associated Pulmonary Artery Hypertension

The purpose of this study was to evaluate the role of 2-D speckle tracking imaging in assessing left ventricular diastolic function in patients with connective tissue disease (CTD). A total of 98 CTD patients and 32 healthy controls were prospectively recruited. Early (E) and late (A) diastolic velocities of the transmitral flow were measured by pulsed Doppler echocardiography. Peak early diastolic myocardial velocity (E') was calculated on tissue Doppler echocardiography. The longitudinal strain rate (SR) was calculated as the average of three apical views, while circumferential and radial SRs were measured in three short-axis views. Pulmonary arterial hypertension (PAH) was defined as systolic pulmonary arterial pressure (sPAP) >36 mm Hg. Compared with the control group, CTD patients exhibited significant impairment of left ventricular diastolic function, manifested as lower global SR during early diastole (SRe) in the longitudinal deformation and higher E/SRe in both longitudinal and radial deformation. CTD-PAH patients had significantly lower SRe and higher E/SRe values in both the longitudinal and radial deformation compared with the patients with CTD without PAH. Pearson's correlation analysis revealed that sPAP levels correlated positively with E/E', longitudinal E/SRe, circumferential E/SRe and radial SRe, and it correlated negatively with septal E' and radial E/SRe. Receiver operating characteristic curve analysis suggested that E/E', longitudinal E/SRe and radial SRe could be used to predict PAH. The present study indicates that 2-D speckle tracking imaging is a useful method for evaluation of left ventricular diastolic function, and these derived parameters can serve as good predictors of PAH, but it may not be superior to the commonly used E/E' in CTD patients.

Diagnostic value of left atrial strain in pediatric hypertrophic cardiomyopathy with normal maximum left atrial volume index: preliminary cardiac magnetic resonance study

BACKGROUND

The maximum left atrial volume index is the most widely used metric for assessing the left atrium in hypertrophic cardiomyopathy; however, it may be normal in the early phases of the disease.

OBJECTIVE

To assess whether pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volume index have impaired atrial functions on cardiac magnetic resonance imaging (MRI).

MATERIALS AND METHOD

A total of 26 pediatric hypertrophic cardiomyopathy patients and 24 age-matched children, as controls, were enrolled in the study. The left atrial reservoir, conduit and booster strain were calculated from two orthogonal planes and the left atrial volumes were calculated using the biplanar method. The extent of left ventricular late gadolinium enhancement (LGE-%) was calculated using the thresholding method. The left ventricular early diastolic longitudinal strain rate was calculated to assess diastolic dysfunction.

RESULTS

The maximum left atrial volume index of the children with hypertrophic cardiomyopathy and the controls were not significantly different (P>0.05). Most of the left atrial functional indices were worse in children with hypertrophic cardiomyopathy (P<0.05), yet no difference was observed between the left atrial booster strains of the two groups (P>0.05). The left atrial conduit strain showed moderate to good negative correlations with left ventricular LGE-% and diastolic dysfunction.

CONCLUSION

Left atrial conduit and reservoir strains are impaired in pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volumetric indices. Most left atrial strain parameters are closely linked to left ventricular LGE-% and diastolic dysfunction. Left atrial strain analysis may reveal subtle functional changes in the atrium before the increase in the maximum volume index.

Cardiac magnetic resonance T2 mapping and feature tracking in athlete's heart and HCM

Objectives

Distinguishing hypertrophic cardiomyopathy (HCM) from left ventricular hypertrophy (LVH) due to systematic training (athlete’s heart, AH) from morphologic assessment remains challenging. The purpose of this study was to examine the role of T2 mapping and deformation imaging obtained by cardiovascular magnetic resonance (CMR) to discriminate AH from HCM with (HOCM) or without outflow tract obstruction (HNCM).

Methods

Thirty-three patients with HOCM, 9 with HNCM, 13 strength-trained athletes as well as individual age- and gender-matched controls received CMR. For T2 mapping, GRASE-derived multi-echo images were obtained and analyzed using dedicated software. Besides T2 mapping analyses, left ventricular (LV) dimensional and functional parameters were obtained including LV mass per body surface area (LVMi), interventricular septum thickness (IVS), and global longitudinal strain (GLS).

Results

While LVMi was not significantly different, IVS was thickened in HOCM patients compared to athlete’s. Absolute values of GLS were significantly increased in patients with HOCM/HNCM compared to AH. Median T2 values were elevated compared to controls except in athlete’s heart. ROC analysis revealed T2 values (AUC 0.78) and GLS (AUC 0.91) as good parameters to discriminate AH from overall HNCM/HOCM.

Conclusion

Discrimination of pathologic from non-pathologic LVH has implications for risk assessment of competitive sports in athletes. Multiparametric CMR with parametric T2 mapping and deformation imaging may add information to distinguish AH from LVH due to HCM.

Key Points

• Structural analyses using T2 mapping cardiovascular magnetic resonance imaging (CMR) may help to further distinguish myocardial diseases.

• To differentiate pathologic from non-pathologic left ventricular hypertrophy, CMR including T2 mapping was obtained in patients with hypertrophic obstructive/non-obstructive cardiomyopathy (HOCM/HNCM) as well as in strength-trained athletes.

• Elevated median T2 values in HOCM/HNCM compared with athlete’s may add information to distinguish athlete’s heart from pathologic left ventricular hypertrophy.

Left ventricular dysfunction in atrial fibrillation and heart failure risk

Aims

This study aimed to investigate the functional correlate, clinical relevance, and prognostic implications of novel left ventricular (LV) deformations in patients with atrial fibrillation (AF).

Methods and results

LV deformational indices, including peak global longitudinal strain (GLS), systolic strain rates (SRs), and early diastolic strain rates (SRe) were measured in a large‐scale AF population. We related such measures to key clinical heart failure (HF) markers, conventional echocardiographic ventricular parameters, and clinical outcomes. Among 1483 subjects with newly diagnosed AF (mean age, 71.6 ± 12.4 years; 55.5% male), worsened GLS (mean, − 12.6 ± 3.9%) and strain rates (SRs and SRe: mean, − 0.86 ± 0.27 and 1.25 ± 0.41 1/s, respectively) by our three‐beat measures were independently correlated with higher C‐reactive protein, N‐terminal pro‐B‐type natriuretic peptide, higher E/e′, more impaired LV ejection fraction (LVEF < 50%), lower estimated glomerular filtration rate, permanent AF, and prevalent HF (all P < 0.05). LV deformations by three‐beat analysis well correlated with the respective results of traditional methods. Abnormal GLS (>− 14.7%) was common in our cohort (67.8%) despite an averaged preserved LVEF (58.4 ± 14.2%), with worse GLS and SRe being associated with higher composite HF re‐admissions/death during the 2.9 year follow‐up (inter‐quartile range, 1.6–4.1 years) in multivariate models incorporating key LV indices (LVEF, LV mass index, and E/e′) (all P < 0.001). Sensitivity analysis by excluding those with regional wall motion abnormality showed broadly similar findings. An improved risk reclassification was observed when GLS and SRe were separately added to the LVEF. Comparison of the AF cohort with a fully matched independent non‐AF cohort at the same baseline LVEF level showed a substantially lower GLS [− 13.2 ± 3.8% (AF) vs. 18.1 ± 3.2% (non‐AF)] and higher clinical events rate (hazard ratio, 1.41 [95% confidence interval, 1.14–1.75]; log‐rank P = 0.002) in the AF cohort.

Conclusions

Impaired LV function defined by myocardial deformation was common in patients with AF and provides independent prognostic values over conventional measures with improved risk prediction. Our data highlight the need for implementing cardiac deformations in daily practice for patients with AF.

Left ventricular global longitudinal strain in bicupsid aortic valve patients: head-to-head comparison between computed tomography, 4D flow cardiovascular magnetic resonance and speckle-tracking echocardiography

Left ventricular global longitudinal strain (LVGLS) analysis is a sensitive measurement of myocardial deformation most often done using speckle-tracking transthoracic echocardiography (TTE). We propose a novel approach to measure LVGLS using feature-tracking software on the magnitude dataset of 4D flow cardiovascular magnetic resonance (CMR) and compare it to dynamic computed tomography (CT) and speckle tracking TTE derived measurements. In this prospective cohort study 59 consecutive adult patients with a bicuspid aortic valve (BAV) were included. The study protocol consisted of TTE, CT, and CMR on the same day. Image analysis was done using dedicated feature-tracking (4D flow CMR and CT) and speckle-tracking (TTE) software, on apical 2-, 3-, and 4-chamber long-axis multiplanar reconstructions (4D flow CMR and CT) or standard apical 2-, 3-, and 4-chamber acquisitions (TTE). CMR and CT GLS analysis was feasible in all patients. Good correlations were observed for GLS measured by CMR (− 21 ± 3%) and CT (− 20 ± 3%) versus TTE (− 20 ± 3%, Pearson’s r: 0.67 and 0.65, p < 0.001). CMR also correlated well with CT (Pearson’s r 0.62, p < 0.001). The inter-observer analysis showed moderate to good reproducibility of GLS measurement by CMR, CT and TTE (Pearsons’s r: 0.51, 0.77, 0.70 respectively; p < 0.05). Additionally, ejection fraction (EF), end-diastolic and end-systolic volume measurements (EDV and ESV) correlated well between all modalities (Pearson’s r > 0.61, p < 0.001). Feature-tracking GLS analysis is feasible using the magnitude images acquired with 4D flow CMR. GLS measurement by CMR correlates well with CT and speckle-tracking 2D TTE. GLS analysis on 4D flow CMR allows for an integrative approach, integrating flow and functional data in a single sequence. Not applicable, observational study.

Association between fragmented QRS complexes and left-ventricular dysfunction in anabolic androgenic steroid users

Background: Anabolic androgen steroid (AS) use has adverse effects on left ventricular functions, such as fibrosis development. Fragmented QRS is an important marker of myocardial fibrosis, while speckle-tracking echocardiographyis a method used to show subclinical left ventricle dysfunction. In this study, we examined the the ability of fQRS + to detect left ventricle fibrosis by speckle tracking echocardiography (STE) in AS users.Methods: The study included a total of 181 healthy athletes. Athletes were divided into two groups as AS users (n = 89) and non-AS users (n = 92). Then, athletes using AS were divided into two groups as fQRS+ (n = 52) and fQRS- (n = 37). In both groups, the arithmetic mean of three images was used to obtain the left ventricle global longitudinal strain (LV-GLS). The E/SRe ratio was also calculated and analysed.Results: There were significant differences between the AS users and non-AS users in terms of, E/SRe (55.7 ± 17.9 vs 50.3 ± 14.8; p = 0.015), LV-GLS (23.1 ± 1.9 vs 24.0 ± 1.7; p = 0.001), and fQRS (18.5% vs 6%; p = 0.005). When subgroup analysis was performed, both LV-GLS and E/SRivr were found to be poor in the fQRS + group. When multiple linear regression analysis was performed, we determined fQRS as an independent predictor for LV-GLS and E/SRivr ratio.Conclusion: In conclusion, our study demonstrated that fQRS is a parameter that can beused to determine left ventricle subclinical systolic and diastolic dysfunction in AS users. It can be used for cessation of drug use, especially in long-term use.

Global diastolic strain rate for the assessment of left ventricular diastolic dysfunction in young peritoneal dialysis patients: a case control study

Background

Left ventricular (LV) myocardial longitudinal diastolic strain rate measured by two-dimensional speckle tracking imaging (2D-STI) was proved to have a better correlation with the LV diastolic function. We aimed to use this sensitive tool to predict LV myocardial diastolic dysfunction in young peritoneal dialysis (PD) patients with preserved LV ejection fraction (LVEF).

Methods

We enrolled 30 PD patients aged ≤60 with LVEF ≥54% and classified as normal LV diastolic function by conventional echocardiography, and 30 age- and sex-matched healthy people as the control group. The left atrial maximum volume index (LAVI), LV mass index (LVMI), LVEF, LV posterior wall thickness (LVPWT), interventricular septal thickness (IVST), peak velocity of tricuspid regurgitation (TR), peak early diastolic velocity/late diastolic velocity (by Pulsed Doppler) (E/A) and E/peak velocity of the early diastolic wave (by Pulsed-wave tissue Doppler) (E/e’) were recorded by conventional echocardiographic. Next, the average LV global longitudinal systolic strain (GLS avg) and the average LV global longitudinal diastolic strain rate (DSr avg) during early diastole (DSrE avg), late diastole (DSrA avg) and isovolumic relaxation period (DSrIVR avg) were obtained from 2D-STI. Combined them with E, the new noninvasive indexes (E/DSrE avg., E/DSrA avg. and E/DSrIVR avg) were derived.

Results

The PD group ‘s LVEF, E/e′, TR and LAVI were in the normal range compared with the controls, and only e′ (p < 0.001) was decreased. The LVMI (p < 0.001), LVPWT (p < 0.001), IVST (p < 0.001) increased while E/A (p < 0.001) decreased. The GLS avg. (p = 0.008) was significantly decreased in PD patients compared with the controls. DSrA avg. (p = 0.006) and E/DSrE avg. (p = 0.006) were increased, while DSrE avg. (p < 0.001), DSrIVR avg. (p = 0.017) and E/DSrA avg. (p < 0.001) decreased. After the multivariable regression analysis, the correlation between DSrE and the conventional parameters including LVPWT (p < 0.001), E/A (p < 0.001) still remained significant.

Conclusions

Young PD patients with preserved LVEF already exhibited myocardial diastolic dysfunction. Global diastolic strain rate indexes were valuable parameters to evaluate diastolic dysfunction. Additionally, LVPWT was highly correlated with DSrE, such parameter should be taken into account for predicting the early LV diastolic dysfunction in clinical practice.

Left Ventricular Relaxation Half-Time as a Predictor of Cardiac Events in Idiopathic Dilated Cardiomyopathy and Hypertrophic Cardiomyopathy With Left Ventricular Systolic and/or Diastolic Dysfunction

PURPOSE

Diastolic dysfunction preceding systolic dysfunction is considered an important interaction in cardiomyopathy with poor prognosis. The aim of this study was to compare left ventricular (LV) isovolumic relaxation with the other parameters as a potential prognostic marker for patients with idiopathic dilated cardiomyopathy (IDC) and hypertrophic cardiomyopathy (HC).

METHODS

A total of 145 patients with IDC and 116 with HC were evaluated for hemodynamic parameters; LV pressure was directly measured by a micromanometer catheter, and relaxation half-time (T_1/2) was used to determine LV isovolumic relaxation. The median follow-up period was 4.7 years.

RESULTS

The mean ages of the patients with IDC and HC were 52.0 ± 12.0 and 57.1 ± 12.4 years, respectively. Each patient group was further divided into 2 groups based on the median value of T_1/2: (1) <41.0 ms (D-L group) and ≥41.0 ms (D-H group) (2) <38.5 ms (H-L group) and ≥38.5 ms (H-H group). Kaplan-Meier analysis showed a significantly higher probability of cardiac events in the D-H group than in the D-L group (p = 0.001) and in the H-H group than in the H-L group (p = 0.028). Further, Cox proportional hazard regression analysis revealed that T_1/2 was an independent predictor of cardiac events for patients with IDC (hazard ratio 1.109; p = 0.007) and HC (hazard ratio 1.062; p = 0.041). In conclusion, regardless of the type of cardiomyopathy, T_1/2 as a measure of LV isovolumic relaxation function was found to be associated with the occurrence of cardiac events.

Lower limit of normality and clinical relevance of left ventricular early diastolic strain rate for the detection of left ventricular diastolic dysfunction

Aims

The aim of the present study was to determine the lower limit of normality and the clinical relevance of left ventricular (LV) early diastolic strain rate (LVSRe) for the detection of LV diastolic dysfunction (LVDD).

Methods and results

Using 2D speckle-tracking echocardiography, we analysed 377 healthy subjects and 475 patients with risk for LVDD with preserved LV ejection fraction (LVEF). The normal range of LVSRe analysing the healthy subjects was 1.56 ± 0.28 s-1, with a lower limit of normality at 1.00 s-1. Using this cut-off, LVSRe was able to detect high rates of LV diastolic alterations (rate 71.1%), which was significantly better than using indirect diastolic parameters such as left atrial volume index (LAVI) and tricuspid regurgitation velocity (TR) (rates 22.9% and 9.1%) and similar to annular mitral parameters such as lateral and septal e' velocity (rates 70.9% and 72.4%). In line, adding LVSRe to the current evaluation of LVDD increased significantly the rate of detection of LVDD (absolute rate of increase 18.9%; rate of detection of LVDD: from 14.3% to 33.2%, P < 0.01). Regarding the clinical relevance of LVSRe, patients with abnormal LVSRe (i.e. <1.00 s-1) had significantly worse New York Heart Association functional class and symptomatic status than those with normal LVSRe. In addition, in a retrospective post hoc analysis, we found that an abnormal LVSRe had a significant association with the risk of heart failure hospitalization at 2 years (odds ratio 5.0, 95% confidence interval 1.3-18.4), which was better than using conventional diastolic parameters such as septal and lateral e' velocity, LAVI and TR velocity.

Conclusion

The findings from this multicentre study provide important data regarding the normal range of LVSRe and highlight the potential clinical relevance of using this new diastolic parameter in the detection of LVDD in patients with preserved LVEF.

4D-flow cardiac magnetic resonance-derived vorticity is sensitive marker of left ventricular diastolic dysfunction in patients with mild-to-moderate chronic obstructive pulmonary disease

Aims

To investigate the possibility that vorticity assessed by four-dimensional flow cardiac magnetic resonance (4D-Flow CMR) in the left ventricle of patients with mild-to-moderate chronic obstructive pulmonary disease (COPD) is a potential marker of early LV diastolic dysfunction (LVDD) and more sensitive than standard echocardiography, and whether changes in vorticity are associated with quantitative computed tomography (CT) and clinical markers of COPD, and right ventricular (RV) echocardiographic markers indicative of ventricular interdependency.

Methods and results

Sixteen COPD patients with presumptive LVDD and 10 controls underwent same-day 4D-Flow CMR and Doppler echocardiography to quantify early and late diastolic vorticity as well as standard evaluation for LVDD. Furthermore, all patients underwent detailed CT analysis for COPD markers including percent emphysema and air trapping. The 4D-Flow CMR derived diastolic vorticity measures were correlated with CT measures, standard clinical and CMR markers, and echocardiographic diastolic RV metrics. Early diastolic vorticity was significantly reduced in COPD patients (P < 0.0001) with normal left ventricular (LV) mass, geometry, systolic function, and no or mild signs of Doppler LVDD when compared with controls. Vorticity significantly differentiated COPD patients without echocardiographic signs of LVDD (n = 11) from controls (P < 0.0001), and from COPD patients with stage I LVDD (n = 5) (P < 0.0180). Vorticity markers significantly correlated with CT computed measures, CMR-derived RV ejection fraction, echocardiographic RV diastolic metrics, and 6-minute walk test.

Conclusion

4D-Flow CMR derived diastolic vorticity is reduced in patients with mild-to-moderate COPD and no or mild signs of LVDD, implying early perturbations in the LV flow domain preceding more obvious mechanical changes (i.e. stiffening and dilation). Furthermore, reduced LV vorticity appears to be driven by COPD induced changes in lung tissue and parallel RV dysfunction.

Influence of age and sex on left ventricular diastolic strain analysis

Speckle tracking analysis (STE) of the left ventricle offers a new method to assess left ventricular (LV) diastolic function. LV diastolic strain measurements offer a non-invasive, global and direct measure of LV diastolic function. However, there is little data on normal values and the influence of anthropomorphic factors which is crucial in clinical practice for new techniques. The aims of this study were to formulate reference values for LV diastolic strain rate, elucidate effects of age and sex on LV diastolic strain analysis and compare STE measurements with conventional LV diastolic measurements. One-hundred-forty-seven healthy subjects aged 20–72 years (≥ 28 subjects per age decade) were prospectively included (Mean age 44 ± 13.7 years, 50% female) and examined with electrocardiography and 2D-echocardiography, including speckle tracking. Left ventricular peak early diastolic strain rate (Sre) was measured in the apical windows, using STE. Men had significantly lower LV Sre values than women (1.02 ± 0.22 vs. 1.18 ± 0.23, p value < 0.001). Left ventricular Sre was inversely associated with age, with values decreasing with ageing. An inverse relation was also found with blood pressure and body surface area. Linear regression analysis showed that LV Sre was independently associated with both age and sex. A multivariable linear regression analysis for LV Sre with conventional LV diastolic variables accounted for 70.9% of the variation of LV Sre, showing good model performance. Reference values for LV Sre are reported and found to be both age- and sex-dependent. Therefore we recommend age- and sex-specific references values to be used in daily clinical practice.

Can Doppler echocardiography estimate raised pulmonary capillary wedge pressure provoked by passive leg lifting in suspected heart failure?

AIMS

Non-invasive estimation of left ventricular filling pressure (LVFP) during stress is important for explaining exertional symptoms in patients with heart failure (HF). The aim of this study was to evaluate ability of Doppler echocardiographic measures of elevated LVFP with passive leg lifting (PLL) in patients with suspected HF.

METHODS

Twenty-nine patients with clinical signs of HF who underwent simultaneous Doppler echocardiography and right heart catheterization (RHC) at rest and during PLL were consecutively investigated. Seventeen patients had normal PCWP (≤15 mmHg) at rest and during PLL and 12 with normal PCWP at rest but >15 mmHg with PLL. Conventional echo and 2D strain were used to assess early diastolic blood flow velocity (E), LV strain rate during early diastole (LVSRe), left atrial SR during atrial contraction (LASRa) and myocardial tissue Doppler velocities to assess lateral e' and further calculate E/e' and E/LVSRe and their relationship with PCWP, at rest and during PLL.

RESULTS

Resting LAVI (β = 0·45, P = 0·009) and LASRa (β = -0·51, P = 0·004) were independently related to PCWP during PLL. Also, LASRa (β = -0·77, P<0·001), E/e' (β = 0·40, P = 0·04) and E/LVSRe (β = 0·47, P = 0·021) during PLL correlated with PCWP during PLL. Multiple regression analysis identified E/LVSRe (β = 0·46, P = 0·001) and LASRa (β = -0·58, P = 0·002) during PLL as being independently associated with PCWP during PLL.

CONCLUSION

Left atrial volume and myocardial contraction (LASRa) at rest both predict unstable LV filling pressures measured as raised PCWP when provoked by PLL. Furthermore, LASRa at PLL seems to have the strongest association to PCWP during PLL.

Fragmented QRS complexes are associated with left ventricular dysfunction in patients with type-2 diabetes mellitus: a two-dimensional speckle tracking echocardiography study

Background: Heart failure may develop independently of coronary artery disease in diabetes mellitus (DM) patients. Fragmented QRS (fQRS) is a marker of myocardial fibrosis or scar tissue and is related to an increase in cardiovascular adverse events. In this study, we examined the utility of speckle tracking echocardiography (STE) in assessing LV function in DM patients with fQRS. Methods and Results: The current study included 178 consecutive patients diagnosed with type-2 DM. The patients included were separated into two groups: those with (n = 50) and without (n = 128) fQRS. The two groups were compared by obtaining LV strain values with STE. Statistically significant differences were also identified between fQRS(-) and fQRS (+) groups with respect to Lv-GLS (p < .001), maxLAVI (p = .020), minLAVI (p < .001), E velocity (p < .001), Em velocity (0.002), E/Em ratio (<0.001) SRe (p < .001), SRe/SRa ratio (p < .001), SRivr (p < .001) and E/SRivr ratio (p < .001). In the multiple linear regression analysis, fQRS (β = -2.077, p = .002) and DM duration (β = -0.216, p = .021) were identified as independent predictors of Lv-GLS. However, fQRS (β = 4.557, p = .001) and minLAVI (β = -2.198, p = .031) were also found to be independent predictors of E/SRivr. We also performed multiple logistic regression analysis and identified Lv-GLS (β = -0.557, p = .001), minLAVI (β = -0.769, p = .001), E/Em ratio (β = 0.650, p = .001) and E/SRivr (β = 0.105, p = .001) as independent predictors of fQRS. Conclusıons: The results of this study revealed that subclinical LV dysfunction was more common in diabetic patients with fQRS. Therefore, determination of fQRS could be an indicator of the diabetic CMP in patients with DM.

Reactive oxygen species damage drives cardiac and mitochondrial dysfunction following acute nano-titanium dioxide inhalation exposure

Nanotechnology offers innovation in products from cosmetics to drug delivery, leading to increased engineered nanomaterial (ENM) exposure. Unfortunately, health impacts of ENM are not fully realized. Titanium dioxide (TiO2) is among the most widely produced ENM due to its use in numerous applications. Extrapulmonary effects following pulmonary exposure have been identified and may involve reactive oxygen species (ROS). The goal of this study was to determine the extent of ROS involvement on cardiac function and the mitochondrion following nano-TiO2 exposure. To address this question, we utilized a transgenic mouse model with overexpression of a novel mitochondrially-targeted antioxidant enzyme (phospholipid hydroperoxide glutathione peroxidase; mPHGPx) which provides protection against oxidative stress to lipid membranes. MPHGPx mice and littermate controls were exposed to nano-TiO2 aerosols (Evonik, P25) to provide a calculated pulmonary deposition of 11 µg/mouse. Twenty-four hours following exposure, we observed diastolic dysfunction as evidenced by E/A ratios greater than 2 and increased radial strain during diastole in wild-type mice (p < 0.05 for both), indicative of restrictive filling. Overexpression of mPHGPx mitigated the contractile deficits resulting from nano-TiO2 exposure. To investigate the cellular mechanisms associated with the observed cardiac dysfunction, we focused our attention on the mitochondrion. We observed a significant increase in ROS production (p < 0.05) and decreased mitochondrial respiratory function (p < 0.05) following nano-TiO2 exposure which were attenuated in mPHGPx transgenic mice. In summary, nano-TiO2 inhalation exposure is associated with cardiac diastolic dysfunction and mitochondrial functional alterations, which can be mitigated by the overexpression of mPHGPx, suggesting ROS contribution in the development of contractile and bioenergetic dysfunction.

Comparison of speckle-tracking echocardiography with invasive hemodynamics for the detection of characteristic cardiac dysfunction in type-1 and type-2 diabetic rat models

Background

Measurement of systolic and diastolic function in animal models is challenging by conventional non-invasive methods. Therefore, we aimed at comparing speckle-tracking echocardiography (STE)-derived parameters to the indices of left ventricular (LV) pressure–volume (PV) analysis to detect cardiac dysfunction in rat models of type-1 (T1DM) and type-2 (T2DM) diabetes mellitus.

Methods

Rat models of T1DM (induced by 60 mg/kg streptozotocin, n = 8) and T2DM (32-week-old Zucker Diabetic Fatty rats, n = 7) and corresponding control animals (n = 5 and n = 8, respectively) were compared. Echocardiography and LV PV analysis were performed. LV short-axis recordings were used for STE analysis. Global circumferential strain, peak strain rate values in systole (SrS), isovolumic relaxation (SrIVR) and early diastole (SrE) were measured. LV contractility, active relaxation and stiffness were measured by PV analysis.

Results

In T1DM, contractility and active relaxation were deteriorated to a greater extent compared to T2DM. In contrast, diastolic stiffness was impaired in T2DM. Correspondingly, STE described more severe systolic dysfunction in T1DM. Among diastolic STE parameters, SrIVR was more decreased in T1DM, however, SrE was more reduced in T2DM. In T1DM, SrS correlated with contractility, SrIVR with active relaxation, while in T2DM SrE was related to cardiac stiffness, cardiomyocyte diameter and fibrosis.

Conclusions

Strain and strain rate parameters can be valuable and feasible measures to describe the dynamic changes in contractility, active relaxation and LV stiffness in animal models of T1DM and T2DM. STE corresponds to PV analysis and also correlates with markers of histological myocardial remodeling.

Electronic supplementary material

The online version of this article (10.1186/s12933-017-0645-0) contains supplementary material, which is available to authorized users.

Association between metabolic syndrome and fragmented QRS complexes: Speckle tracking echocardiography study

BACKGROUND

Metabolic syndrome (MetS) is an endocrinological disease with both metabolic and physiological components. Previous studies have shown a relationship between MetS and left ventricular (LV) dysfunction. A fragmented QRS (fQRS) is a reliable electrocardiogram (ECG) finding with the importance of an indicator of myocardial fibrosis and scarring. In this study, we examined the utility of speckle tracking echocardiography (STE) in assessing LV function in MetS patients with fQRS.

METHODS

The 164 consecutive MetS patients included in the study. They were separated into two groups; those with (n=33) and those without (n=131) fQRS. The two groups were compared by obtaining LV strain values with STE.

RESULTS

Statistically significant differences between the fQRS (-) and fQRS (+) groups were identified for LV global longitudinal strain (LV-GLS) (p<0.001), maximum left atrial volume index (maxLAVI) (p≤0.001), strain rate during isovolumic relaxation period (SRivr) (p<0.001), and the E/SRivr ratio (p<0.001). In the multiple linear regression analysis, fQRS (β=-1.456, p=0.003), diabetes mellitus (β=-0.973, p=0.015), hypertension (β=-0.820, p=0.015) and MaxLAVI (β=-0.142, p=0.018) were independent predictors of LV-GLS. However, fQRS (β=21.995, p<0.001), MaxLAVI (β=3.090, p<0.001), and E/Em ratio (β=3.326, p<0.001) were also independent predictors of E/SRivr.

CONCLUSIONS

The results of this study showed that LV dysfunction was more common in MetS patients with fQRS. MetS patients, and especially those who are fQRS (+), should thus be closely monitored for subclinical LV systolic and diastolic dysfunction.

Left atrial function and phenotypes in asymmetric hypertrophic cardiomyopathy

BACKGROUND

Few studies have analyzed changes in left atrial (LA) function associated with different phenotypes of asymmetric hypertrophic cardiomyopathy (HCM). We sought to demonstrate the association of impairments in LA function with disease phenotype in patients with obstructive and nonobstructive HCM.

METHODS

From Stanford Cardiomyopathy Registry, we randomly selected 50 age-/sex-matched healthy controls, 35 patients with nonobstructive HCM (HCM 1), 35 patients with obstructive HCM (HCM 2), and 35 patients with obstructive HCM requiring septal reduction therapy (HCM 3). Echocardiography was performed to evaluate left ventricular (LV) strain as well as LA function including LA emptying fraction and LA strain.

RESULTS

The mean age was 51±14 years and 57% were male. LA volume index differed among all four predefined groups (25.6±6.7 mL/m² in controls, 32.2±13.3 mL/m² in HCM 1, 42.0±12.9 mL/m² in HCM 2, 52.4±15.2 mL/m² for HCM 3, and P<.05 all between groups). All measurement of LA function was impaired in patients with HCM than controls. Total and passive LA function was further impaired in HCM 2 or 3 compared with HCM 1, while active LA function was not different among the three groups. Among LV strains, only septal longitudinal strain differed among all groups (-18.5±1.9% in controls, -14.5±1.9% in HCM 1, -13.3±1.8% in HCM 2, -11.6±2.3% in HCM 3, and P<.05 all between groups).

CONCLUSIONS

LA function was impaired in patients with HCM even in minimally symptomatic nonobstructive phenotype. Total and passive LA function was further impaired in patients with obstructive HCM.

Left ventricular flow propagation velocity measurement: Is it cast in stone?

This study aims to investigate the measurement of left ventricular flow propagation velocity, V _p, using phase contrast magnetic resonance imaging and to assess the discrepancies resulting from inflow jet direction and individual left ventricular size. Three V _p measuring techniques, namely non-adaptive (NA), adaptive positions (AP) and adaptive vectors (AV) method, were suggested and compared. We performed the comparison on nine healthy volunteers and nine post-infarct patients at four measurement positions, respectively, at one-third, one-half, two-thirds and the conventional 4 cm distances from the mitral valve leaflet into the left ventricle. We found that the V _p measurement was affected by both the inflow jet direction and measurement positions. Both NA and AP methods overestimated V _p, especially in dilated left ventricles, while the AV method showed the strongest correlation with the isovolumic relaxation myocardial strain rate (r = 0.53, p < 0.05). Using the AV method, notable difference in mean V _p was also observed between healthy volunteers and post-infarct patients at positions of: one-half (81 ± 31 vs. 58 ± 25 cm/s), two-thirds (89 ± 32 vs. 45 ± 15 cm/s) and 4 cm (98 ± 23 vs. 47 ± 13 cm/s) distances. The use of AV method and measurement position at one-half distance was found to be the most suitable method for assessing diastolic dysfunction given varying left ventricular sizes and inflow jet directions.

Precision Phenotyping in Heart Failure and Pattern Clustering of Ultrasound Data for the Assessment of Diastolic Dysfunction

OBJECTIVES

The aim of this study was to investigate whether cluster analysis of left atrial and left ventricular (LV) mechanical deformation parameters provide sufficient information for Doppler-independent assessment of LV diastolic function.

BACKGROUND

Medical imaging produces substantial phenotyping data, and superior computational analyses could allow automated classification of repetitive patterns into patient groups with similar behavior.

METHODS

The authors performed a cluster analysis and developed a model of LV diastolic function from an initial exploratory cohort of 130 patients that was subsequently tested in a prospective cohort of 44 patients undergoing cardiac catheterization. Patients in both study groups had standard echocardiographic examination with Doppler-derived assessment of diastolic function. Both the left ventricle and the left atrium were tracked simultaneously using speckle-tracking echocardiography (STE) for measuring simultaneous changes in left atrial and ventricular volumes, volume rates, longitudinal strains, and strain rates. Patients in the validation group also underwent invasive measurements of pulmonary capillary wedge pressure and LV end diastolic pressure immediately after echocardiography. The similarity between STE and conventional 2-dimensional and Doppler methods of diastolic function was investigated in both the exploratory and validation cohorts.

RESULTS

STE demonstrated strong correlations with the conventional indices and independently clustered the patients into 3 groups with conventional measurements verifying increasing severity of diastolic dysfunction and LV filling pressures. A multivariable linear regression model also allowed estimation of E/e' and pulmonary capillary wedge pressure by STE in the validation cohort.

CONCLUSIONS

Tracking deformation of the left-sided cardiac chambers from routine cardiac ultrasound images provides accurate information for Doppler-independent phenotypic characterization of LV diastolic function and noninvasive assessment of LV filling pressures.

Speckle-Tracking Echocardiographic Measures of Right Ventricular Diastolic Function Correlate with Reference Standard Measures Before and After Preload Alteration in Children

The accuracy of echocardiographic measures of right ventricular (RV) diastolic function has been sparsely studied. Our objective was to evaluate the correlation between echocardiographic and reference standard measures of RV diastolic function derived from micromanometer pressure analysis before and after preload alteration in children. Echocardiograms and micromanometer pressure analyses were prospectively performed before and after fluid bolus in children undergoing right heart catheterization. The isovolumic relaxation time constant (τ) and end-diastolic pressure (EDP) were measured. Conventional and speckle-tracking echocardiographic (STE) parameters of RV systolic and diastolic function were assessed. Normal saline bolus was given to increase RV EDP by 20 %. Twenty-eight studies were performed in 22 patients with congenital heart disease or postheart transplantation. Mean age was 8.7 ± 6.1 years. RV longitudinal early diastolic strain rate (EDSR) correlated with τ before (r = 0.57, p = 0.001) and after fluid bolus (r = 0.48, p = 0.008). No conventional echocardiographic measures correlated with τ both before and after fluid bolus. Multiple regression analysis revealed RV EDSR and LV circumferential EDSR as independent predictors of RV τ. There were no independent predictors of EDP. RV EDSR appears to correlate with the reference standard measure of early active ventricular relaxation in children at baseline and after changes in preload. Conventional echocardiographic measures of diastolic function were not predictive of diastolic function after preload alteration. Future studies should assess the prognostic significance of STE measures of diastolic function in this population.

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

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

Left Ventricular Global Strain for Estimating Relaxation and Filling Pressure - A Multicenter Study

BACKGROUND

Speckle-tracking echocardiography (STE)-derived parameters may have better correlation with left ventricular (LV) relaxation and filling pressure than tissue Doppler-derived parameters. However, it has not been elucidated which parameter - strain or strain rate - and which direction of myocardial deformation - longitudinal or circumferential - is the most useful marker of LV relaxation and filling pressure.

METHODS AND RESULTS

We conducted a prospective multicenter study and compared the correlation of tissue Doppler- and STE-derived parameters with the time constant of LV pressure decay (τ) and LV mean diastolic pressure (MDP) in 77 patients. The correlation of early-diastolic mitral annular velocity (e´) with τ was weak (r=-0.32, P<0.01), and that of peak longitudinal strain (LS) was the strongest (r=-0.45, P<0.001) among the STE-derived parameters. There was a modest correlation between LVMDP and the ratio of early-diastolic inflow velocity (E) to e´ (E/e´) (r=0.50, P<0.001). In contrast, the ratio of E to LS (E/LS) correlated strongly with LVMDP (r=0.70, P<0.001). The correlation of E/LS with LVMDP was significantly better than that for E/e´ (P<0.01). Receiver-operating characteristic analysis showed that E/LS had the largest area under the curve for distinguishing elevated LVMDP (E/LS 0.86, E/e´ 0.74, E/A 0.67).

CONCLUSIONS

STE-derived longitudinal parameters correlated well with LV relaxation and filling pressure. In particular, E/LS could be more accurate than E/e´ for estimating LV filling pressure. (Circ J 2016; 80: 1163-1170).

Correlation of Global Strain Rate and Left Ventricular Filling Pressure in Patients with Coronary Artery Disease: A 2-D Speckle-Tracking Study

The aim of the present study was to evaluate the role of 2-D speckle-tracking imaging in the prediction of left ventricular filling pressure in patients with coronary artery disease (CAD) and normal left ventricular ejection fraction (LVEF). Eighty-four patients with CAD and 30 healthy controls were recruited prospectively. The longitudinal strain rate (SR) curves were determined in three apical views of the left ventricle long axis. Circumferential and radial SR curves were determined in three short-axis views. Left ventricular end-diastolic pressure (LVEDP) was invasively obtained by left heart catheterization. Compared with the 30 controls, the patients with CAD had significantly lower global SR during early diastole (SRe) and higher E/SRe in three directions of myocardial deformation. CAD patients with elevated LVEDP had significantly lower SRe and higher E/SRe of three deformations. Pearson's correlation analysis revealed that LVEDP correlated positively with E/E' ratio, radial SRe and longitudinal and circumferential E/SRe. LVEDP correlated negatively with longitudinal and circumferential SRe and radial E/SRe. Receiver operating characteristic curve analysis revealed that these SR indexes predicted elevated LVEDP (areas under the curve: longitudinal E/SRe = 0.74, circumferential E/SRe = 0.74, circumferential SRe = 0.70, longitudinal SRe = 0.69, radial E/SRe = 0.68, radial SRe = 0.65), but neither was superior to the tissue Doppler imaging index E/E' (area under the curve = 0.84). The present study indicates that 2-D speckle-tracking imaging is a practical method for evaluating LV filling pressure, but it might not provide additional advantages compared with E/E' in CAD patients.

Evaluation of Left Ventricular Diastolic Dysfunction with Early Systolic Dysfunction Using Two-Dimensional Speckle Tracking Echocardiography in Canine Heart Failure Model

BACKGROUND

This study evaluated the role of two-dimensional speckle tracking echocardiography (2DSTE) for predicting left ventricular (LV) diastolic dysfunction in pacing-induced canine heart failure.

METHODS

Pacing systems were implanted in 8 adult mongrel dogs, and continuous rapid right ventricular pacing (RVP, 240 beats/min) was maintained for 2 weeks. The obtained measurements from 2DSTE included global strain rate during early diastole (SRe) and during late diastole (SRa) in the longitudinal (L-SRe, L-SRa), circumferential (C-SRe, C-SRa), and radial directions (R-SRe, R-SRa). Changes in heart morphology were observed by light microscopy and transmission electron microscopy at 2 weeks.

RESULTS

The onset of LV diastolic dysfunction with early systolic dysfunction occurred 3 days after RVP initiation. Most of the strain rate imaging indices were altered at 1 or 3 days after RVP onset and continued to worsen until heart failure developed. Light and transmission electron microscopy showed myocardial vacuolar degeneration and mitochondrial swelling in the left ventricular at 2 weeks after RVP onset. Pearson's correlation analysis revealed that parameters of conventional echocardiography and 2DSTE showed moderate correlation with LV pressure parameters, including E/Esep' (r = 0.58, P < 0.01), L-SRe (r = -0.58, P < 0.01), E/L-SRe (r = 0.65, P < 0.01), and R-SRe (r = 0.53, P < 0.01). ROC curves analysis showed that these indices of conventional echocardiography and strain rate imaging could effectively predict LV diastolic dysfunction (area under the curve: E/Esep' 0.78; L-SRe 0.84; E/L-SRe 0.80; R-SRe 0.80).

CONCLUSION

2DSTE was a sensitive and accurate technique that could be used for predicting LV diastolic dysfunction in canine heart failure model.