Emerging clinical role of strain imaging in echocardiography

Cardiac Computed Tomography-Derived Left Atrial Strain and Volume in Pediatric Patients With Congenital Heart Disease: A Comparative Analysis With Transthoracic Echocardiography

Purpose

This study aimed at exploring the feasibility and reproducibility of CCT for the measurement of Left Atrial (LA) strain and volume compared with transthoracic echocardiography (TTE) in pediatric patients with congenital heart disease (CHD).

Materials and Methods

The present study included 43 postoperative patients with CHD (7.39 ± 3.64 years, 56% male) who underwent clinically indicated CCT, and all patients underwent additional TTE on the same day. LA strain and volume parameters were measured by dedicated software. The correlation and agreement of LA strain and volume parameters were assessed using Pearson’s correlation coefficient and Bland-Altman analysis. Intra-class correlation coefficients (ICC) were used to assess CCT intra-observer and inter-observer reproducibility.

Results

All strain parameters of CCT were lower compared to TTE (reservoir strain: 28.37 ± 6.92 vs. 32.15 ± 8.15, respectively; conduit strain: 21.33 ± 6.46 vs. 24.23 ± 7.75, respectively; booster strain: 7.04 ± 2.74 vs. 7.92 ± 3.56). While the volume parameters of CCT were higher compared to TTE (LAV: 29.60 ± 19.01 vs. 25.66 ± 17.60, respectively; LAVi: 30.36 ± 22.31 vs. 28.63 ± 19.25, respectively). Both LA strain and volume measurements showed good correlation and agreement between the two modalities (r = 0.63–0.87, p < 0.001). CT-derived LA strain and volume measurements showed good intra- and inter-observer reproducibility using prototype software (ICC = 0.78–0.96).

Conclusions

CCT was feasible for measuring LA strain and volume with good correlation and high reproducibility as compared with TTE. As a complementary modality, CCT can regard as an accepted method in the evaluation of LA function in pediatric patients with CHD

Myocardial involvement in Behçet's disease may be higher in patients with Neuro-Behçet's disease: a speckle tracking echocardiographic study

BACKGROUND

Behcet's disease (BD) may present with life threating complications including neurological and cardiovascular involvement. Neuro-Behcet's disease (NBD) is one of the most important causes of morbidity and mortality in patients with BD. The aim of the present study is to investigate whether patients with NBD are different than BD patients with other manifestations in terms of subclinical myocardial dysfunction.

METHODS

Forty patients with NBD (23 female, mean age: 42.4 ± 9.4 years), 40 patients with BD (9 female, mean age: 39.7 ± 9.0 years) and 40 controls (20 male, mean age: 41.8 ± 6.5 years) were consecutively included in the study. All subjects underwent a transthoracic echocardiography for evaluation of left ventricular (LV) and atrial (LA) functions with two-dimensional (2D) speckle tracking echocardiography (STE).

RESULTS

Baseline characteristics, clinical data, LV dimensions, systolic and diastolic functions were all in normal range among the groups. LV global longitudinal strain (LV-GLS) was significantly lower in patients with NBD and BD patients without neurologic involvement compared to controls. LA conduit strain was significantly lower in patients with NBD compared to controls. Patients with both parenchymal NBD and vascular NBD manifestations had significantly lower LV-GLS and LA conduit strain compared to controls. Linear regression analysis demonstrated that among cardiovascular risk factors only presence of NBD was the independent predictor of LV-GLS.

CONCLUSIONS

BD is associated with impaired LV and LA functions. LV-GLS and LA conduit strains of the patients with NBD were lower. NBD was an independent predictor of LV-GLS, suggesting a link between neurological manifestations and cardiac dysfunction in BD patients.

Postoperative evaluation of left ventricular global strain using cardiac computed tomography in pediatric patients with congenital heart disease: A comparison with echocardiography

PURPOSE

We explored the feasibility and reproducibility of cardiac computed tomography (CCT)-derived left ventricular (LV) global strain in postoperative children
with congenital heart disease (CHD) and compared its correlation and agreement with transthoracic echocardiography (TTE).

METHODS

Fifty-one patients (28 males, 23 females) were included who underwent clinically indicated retrospective electrocardiography-triggered CCT. and all patients underwent additional TTE on the same day. LV global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were measured. Correlations of global strains between CCT and TTE were assessed using Pearson's correlation coefficient. Intra-class correlation coefficients (ICC) were used to assess CCT intra-observer and inter-observer reproducibility.

RESULTS

GLS and GCS were not significantly different between CCT and TTE (GLS: -23.54 ± 3.24 vs. -23.85 ± 3.72, respectively, p = 0.415; GCS: -28.21 ± 3.55 vs. -28.79 ± 3.69, respectively, p = 0.155). GRS was significantly different between CCT and TTE (60.79 ± 15.11 vs. 41.73 ± 4.27, respectively, p < 0.001). There was good correlation between CCT- and TTE-derived GLS (r = 0.70, p < 0.001) and GCS (r = 0.68, p < 0.001), but GRS showed no correlation between CCT and TTE (r = 0.09, p = 0.54). CCT-derived global strain showed good intra- and inter-observer reproducibility (ICC = 0.86-0.92), except the inter-observer reproducibility for GRS (ICC = 0.77).

CONCLUSIONS

CCT was feasible for postoperative evaluation of LV global strain in pediatric patients with CHD with sufficient reproducibility. CCT-derived global strain can provide additional information in selected CHD patients with poor acoustic windows and who are intolerant to or have contraindications for cardiac magnetic resonance.

Feasibility of CT-derived myocardial strain measurement in patients with advanced cardiac valve disease

To explore the feasibility of CT-derived myocardial strain measurement in patients with advanced cardiac valve disease and to compare it to strain measurements derived from transthoracic echocardiography (TTE). 43 consecutive patients with advanced cardiac valve disease and clinically indicated retrospectively gated cardiac CTs were retrospectively analyzed. The longitudinal, circumferential as well as radial systolic strain were determined in all patients utilizing a commercially available CT strain software. In 36/43 (84%) patients, CT-derived longitudinal strain was compared to speckle-tracking TTE. Pearson’s correlation coefficients as well as Bland–Altman analysis were used to compare the CT-derived strain measurements to TTE. The intra- and inter-reader-reliability of the CT-derived strain measurements were assessed by intra-class correlation coefficients (ICCs). Strain measurements were feasible in all patients. CT-derived global longitudinal strain (GLS) correlated moderately with TTE-derived GLS (r = 0.6, p < 0.001). A moderate correlation between CT-derived GLS and CT-derived left ventricular ejection fraction was found (LVEF, r = − 0.66, p = 0.036). Bland–Altman analysis showed a systematic underestimation of myocardial strain by cardiac CT compared to TTE (mean difference: − 5.8%, 95% limit of agreement between − 13.3 and 1.8%). Strain measurements showed an excellent intra- and inter-reader-reliability with an intra-reader ICC of 1.0 and an inter-reader ICC of 0.99 for GLS measurements. CT-derived myocardial strain measurements are feasible in patients with advanced cardiac valve disease. They are highly reproducible and correlate with established parameters of strain measurements. Our results encourage the implementation of CT-derived strain measurement into clinical routine.

The strain and strain rate imaging paradox in echocardiography: overabundant literature in the last two decades but still uncertain clinical utility in an individual case

Almost two decades ago strain and strain rate imaging were proposed as a new, potentially more sensitive modality for quantifying both regional and global myocardial function. Until now, however, strain and strain rate imaging have been slow to be incorporated into everyday clinical practice. More recently, two dimensional strain has been claimed as of greater clinical utility, given that it is angle independent, with improved feasibility and reproducibility as compared to tissue Doppler strain. Nevertheless, speckle tracking strain is reliant on 2D image quality and frame rates. Three dimensional speckle tracking could eliminate the problem of through-plane motion inherent in 2D imaging, but 3D strain is currently limited by low frame rates. Another limitation of strain imaging is that the results are dependent on the ultrasound machine on which analyses are performed, with variability in measurements between different vendors. Despite the diagnostic and prognostic advantages of 2D strain, there is a lack of specific therapeutic interventions based on strain and a paucity of long-term large-scale randomized trial evidence on cardiovascular outcomes. After overabundant literature the same definition of normal cut-off values is controversial and not univocal. Further studies are needed, involving both manufacturers and medical professionals, on the additive contribution, possibly different case by case, of interfering and artifactual factors, aside from myocardial function per se. These artifactual determinants and motion artifacts components could be dominant in individual cases and should always be taken into account in the clinical decision making process in a single case.

Abnormal diastolic function and Global longitudinal strain in patients with Thalassemia Major on long term chelation therapy

Cardiac complications are the major cause of mortality in patients with Thalassemia major (TM). Cardiac T2* MRI is currently the gold standard for assessing myocardial iron concentration. The aim of our study was to assess whether any echocardiographic parameter would correlate with these findings in patients well established on chelation therapy. This was a prospective study on patients with TM who are regularly followed in our clinic. Patients had a cardiac MRI and echocardiogram within 2 months of each other. Echo parameters included global longitudinal strain and diastolic function. We also compared these findings with those from a cohort of thalassemia intermedia (TI) and normal controls. A total of 84 patients (mean age 26.3 ± 6.1 years, 42.8% male) with TM were enrolled. All had normal left ventricular ejection fraction and only 8 patients had MRI T2* < 10. As compared to 17 patients with TI and 53 controls, these patients had significantly higher E/E' and lower pulmonary vein s/dd ratio suggesting early diastolic dysfunction. 28 patients fulfilled criteria for diastolic dysfunction even in the presence of normal MRI T2*. Global longitudinal strain (GLS) was significantly lower in the TM group as compared to the TI and controls. We found no correlation between any of the echo findings and the MRI T2*in TM patients. In patients with thalassemia and MRI T2* > 20 ms features of diastolic dysfunction persist even in the presence of normal LV function and normal GLS. This suggests that diastolic function remains abnormal even when myocardial iron concentrations are normal and follow up therefore is essential.

Speckle tracking echocardiography for the evaluation of left ventricular function in children with systemic lupus erythematosus

BACKGROUND

Many studies in adult patients with systemic lupus erythematosus (SLE) have demonstrated that myocardial dysfunction was significantly associated with enhanced disease activity. However, similar studies in paediatric patients with SLE are limited. The aim of this study was to evaluate the role of speckle tracking echocardiography (STE) to detect left ventricular dysfunction in children with active and inactive SLE.

METHODS

This prospective case-control study was carried out on 50 children with SLE. Thirty healthy age- and sex-matched children comprised the control group. The patients were further subdivided into two subgroups: active SLE and inactive SLE. Laboratory investigations undertaken included complete blood count, renal function, C3, C4, ANA, anti-dsDNA and serum N-terminal pro-B type natriuretic peptide. Echocardiographic examinations were performed on all children and included conventional echocardiography, tissue Doppler imaging (TDI) and two- and three-dimensional STE.

RESULTS

There was no statistically significant difference in N-terminal pro B natriuretic peptide between the studied groups. The myocardial performance index by TDI was statistically significantly higher in SLE patients compared to controls. STE parameters were statistically significantly lower in SLE patients compared to controls. There was no correlation between STE parameters and disease activity.

CONCLUSIONS

STE could be a promising technique in the early detection of subclinical left ventricular dysfunction in children with SLE.

Speckle Tracking Analysis of Left Ventricular Systolic Function Following Traumatic Brain Injury: A Pilot Prospective Observational Cohort Study

BACKGROUND

Systolic dysfunction and reduction in left ventricular ejection fraction (LVEF) has been documented after traumatic brain injury (TBI). Speckle tracking is an emerging technology for myocardial strain assessment which has been utilized to identify subclinical myocardial dysfunction, and is most commonly reported as global longitudinal strain (GLS). We examined myocardial strain and regional strain patterns following moderate-severe TBI.

MATERIALS AND METHODS

We conducted a prospective cohort study of moderate-severe TBI patients (Glasgow Coma Scale≤12) and age/sex-matched controls. Transthoracic echocardiography was performed within the first day and 1 week following TBI. Myocardial function was assessed using both GLS and LVEF, and impaired systolic function was defined as GLS >-16% or LVEF ≤50%. Regional strain patterns and individual strain trajectories were examined.

RESULTS

Thirty subjects were included, 15 patients with TBI and 15 age/sex-matched controls. Among patients with adequate echocardiographic windows, systolic dysfunction was observed in 2 (17%) patients using LVEF and 5 (38%) patients using GLS within the first day after TBI. Mean GLS was impaired in patients with TBI compared with controls (-16.4±3.8% vs. -20.7±1.8%, P=0.001). Regional myocardial examination revealed impaired strain primarily in the basal and mid-ventricular segments. There was no improvement in GLS from day 1 to day 7 (P=0.81).

CONCLUSIONS

Myocardial strain abnormalities are common and persist for at least 1 week following moderate-severe TBI. Speckle tracking may be useful for the early diagnosis and monitoring of systolic dysfunction following TBI.

High-Intensity Interval Training Improves Left Ventricular Contractile Function

INTRODUCTION

Improved myocardial contractility is a critical circulatory adaptation to exercise training. However, the types of exercise that enhance left ventricular (LV) contractile and diastolic functions have not yet been established. This study investigated how high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) influence LV mechanics during exercise.

METHODS

Fifty-four healthy sedentary men were randomized to engage in either HIIT (3-min intervals at 40% and 80% of V˙O2max, n = 18) or MICT (sustained 60% of V˙O2max, n = 18) for 30 min·d, 5 d·wk for 6 wk or to a control group (n = 18) that did not engage in exercise intervention. LV mechanics during semiupright bicycle exercise tests were measured by two-dimensional speckle-tracking echocardiography.

RESULTS

Before the interventions, acute bicycle exercise increased (i) peak basal/apical radial and circumferential and peak longitudinal strains and strain rates, (ii) peak basal/apical rotations and torsion, and (iii) peak systolic twisting and early diastolic untwisting velocities in the LV. After the interventions, the HIIT group exhibited greater LV mass and diastolic internal diameter as well as higher ratio of E wave to A wave and early diastolic propagation velocity than did the MICT group. Despite decreased peak apical rotation and torsion, HIIT enhanced peak apical radial strain and strain rate as well as shortened the time to reach peak untwisting velocity in the LV during exercise. However, the LV mechanics during exercise were unchanged in the control group.

CONCLUSION

HIIT but not MICT induces eccentric myocardial hypertrophy. Moreover, HIIT effectively improves the LV mechanics during exercise by increasing contractile and diastolic functions.

Review of Echocardiographic Findings in Patients with Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) causes recurrent apneas due to upper respiratory tract collapse, leading to sympathetic nervous system hyperactivation and increased cardiovascular risk. Moderate and severe forms of obstructive sleep apnea are associated with increased atrial volumes and affect left ventricular diastolic and then systolic function. Right ventricular ejection fraction can be accurately assessed via three-dimensional echocardiography, while bidimensional imaging can only provide a set of surrogate parameters to characterize systolic function (tricuspid annulus plane systolic excursion, right ventricular fractional area change, and lateral S'). Tissue Doppler imaging is a more sensitive tool in detecting functional ventricular impairment, but its use is limited by angle dependence and the unwanted influence of tethering forces. Two-dimensional speckle tracking echocardiography is considered more suitable for the assessment of ventricular function, as it is able to distinguish between active and passive wall motion. Abnormal strain values, a marker of subclinical myocardial dysfunction, can be detected even in patients with normal ejection fraction and chamber volumes. The left ventricular longitudinal strain is more affected by the presence of obstructive sleep apnea than circumferential strain values. Although the observed OSA-induced changes are subtle, the benefit of a detailed echocardiographic screening for subclinical heart failure in OSA patients on therapy adherence and outcome should be addressed by further studies.

Fragmented QRS as a predictor of in-hospital life-threatening arrhythmic complications in ST-elevation myocardial infarction patients

BACKGROUND

Fragmented QRS (fQRS) complex is an electrocardiographic pattern that reflects the inhomogeneity of ventricular depolarization. The aims of this study were to determine the prognostic significance of fQRS for predicting in-hospital life-threatening arrhythmic complications in ST-elevation myocardial infarction (STEMI) patients, and to identify the most appropriate duration of cardiac rhythm monitoring in STEMI patients with fQRS.

METHODS

Patients diagnosed with and treated for STEMI at Siriraj Hospital (Bangkok, Thailand) during 2009-2012 were enrolled. Patients were divided according to fQRS status (having or not having fQRS) at hospital admission. The primary outcome was in-hospital life-threatening arrhythmic events, including sustained ventricular tachycardia and ventricular fibrillation. Time to last life-threatening arrhythmic event from hospital admission was recorded.

RESULTS

Of the 452 patients that were included, 96 patients (21.2%) had fQRS. There were significantly more life-threatening arrhythmic events in the fQRS group than in the non-fQRS group (22.9% vs. 4.5%, respectively; p < 0.001). Median (IQR) time to last life-threatening arrhythmic event from hospital admission was significantly longer in fQRS than in non-fQRS (6.58 hr [3.08-39.34] vs. 2.59 hr [1.75-5.75], respectively; p = 0.047). Multivariate analysis identified fQRS as an independent predictor of in-hospital life-threatening arrhythmic events (OR: 4.162, 95% CI: 1.669-10.384; p = 0.002).

CONCLUSIONS

The presence of fQRS complex on admission ECG was found to be an independent predictor of in-hospital life-threatening arrhythmic events in STEMI patients. Since the time to last life-threatening arrhythmic event from admission was longer in fQRS than in non-fQRS, cardiac rhythm monitoring longer than 24-48 hr may be needed in patients with fQRS.

Myocardial deformation in iron overload cardiomyopathy: speckle tracking imaging in a beta-thalassemia major population

Traditional echocardiography is unable to detect neither the early stages of iron overload cardiomyopathy nor myocardial iron deposition. The aim of the study is to determine myocardial systolic strain indices in thalassemia major (TM), and assess their relationship with T2*, a cardiac magnetic resonance index of the severity of cardiac iron overload. 55 TM cases with recent cardiac magnetic resonance (CMR-T2*) underwent speckle tracking analysis to assess regional myocardial strains and rotation. The results were compared with a normal control group (n = 20), and were subsequently analyzed on the basis of the CMR-T2* values. Two TM groups were studied: TM with significant cardiac iron overload ("low" T2*, ≤20 ms; n = 21), and TM with normal T2* values ("normal" T2*, >20 ms; n = 34). TM patients show significant, uniform decrease in circumferential and radial strain (P < 0.05), and a remarkable reduction in end-systolic rotation, both global, and for all segments (P < 0.001). No significant differences were found between the low- and the normal T2* group either in regional strains and rotation or in standard echocardiographic and CMR parameters. Spearman's correlation coefficient shows no significant correlation between myocardial strains, rotation and cardiac T2* values. In conclusion, our results are in accordance with recent evidence that myocardial iron overload is not the only mechanism underlying iron cardiomyopathy in TM. Strain imaging can predict subclinical myocardial dysfunction irrespective of CMR-T2* values, although it cannot replace CMR-T2* in assessing cardiac iron overload. Finally, it might be useful to appropriately time cardioactive treatment.

2D-STI combined with gated 99Tcm-MIBI MPI for the diagnosis of myocardial ischemia in hypercholesterolemia patients

This study aimed to investigate the reliability of ultrasound two-dimensional speckle tracking imaging (2D-STI) for the evaluation of myocardial ischemia in familial hypercholesterolemia (FH) patients. We recruited 28 patients clinically diagnosed with homozygous familial hypercholesterolemia (HoFH) and subjected them to 2D-STI, gated transthoracic Doppler echocardiography (TTDE), and ⁹⁹Tc^m-methoxyisobutylisonitrile myocardial perfusion imaging (⁹⁹Tc^m-MIBI MPI). The sensitivity, specificity and diagnostic accordance rate of TTDE and 2D-STI for myocardial ischemia in HoFH patients were compared with the ⁹⁹Tc^m-MIBI scores. According to the diagnosis of ischemia in the three main coronary arteries (LAD, LCX, and RCA) by MPI, patients were further divided into different groups for comparing segmental strain by 2D-STI. The total correlation between TTDE and ⁹⁹Tc^m-MIBI MPI for evaluation of myocardial ischemia was r=0.483 and between 2D-STI and ⁹⁹Tc^m-MIBI MPI was 0.786. The total correlation index for ejection fraction (EF) between TTDE and ⁹⁹Tc^m-MIBI MPI was r=0.606 and for 2D-STI and ⁹⁹Tc^m-MIBI MPI was r=0.919. TTDE indicated that differences among LVDd, LVDs, IVS, LVPW, AO Vmax, PG, E/e', and DT were statistically significant. STI indicated that the total strain of the ischemia group was lower than that of the non-ischemia group. The total systolic strain and total early diastolic strain of the ischemia group were lower than that of the non-ischemia group. TTDE can be used for primary observation and evaluation of ventricular wall ischemia for HoFH patients. Ultrasound 2D-STI is better than TTDE in the evaluation of myocardial ischemia in HoFH patients. Ultrasound 2D-STI shows the same effectiveness as ⁹⁹Tc^m-MIBI MPI for the detection of myocardial ischemia, serving as good tool for prognosis and treatment evaluation in HoFH patients.

Investigation of the predictive value of speckle tracking imaging for the assessment of cardiac function and clinical prognosis in patients with hypercholesterolemia

The predictive value of speckle tracking imaging (STI) for the assessment of cardiac function and clinical prognosis in patients with hypercholesterolemia was explored. One hundred forty-seven patients with hypercholesterolemia diagnosed in our hospital and 137 healthy adults from our health examination center over the same period were included in this study. Using STI and color Doppler ultrasound, we carried out follow-up of cardiac function in patients with hypercholesterolemia and statistical analysis based on collected data. Global longitudinal strain, global circumferential strain, and the strains of apical long-axis, four-chamber and two-chamber planes, and short-axis mitral valve, short-axis papillary muscle, and short-axis apical levels in the hypercholesterolemia group were significantly lower than those in the control group. Global systolic and early diastolic strain rates were significantly lower than those in the control group. In the coronaries, the percentage of segments with significant differences was 80% (24/30) in the left anterior descending coronary artery (LAD), 66.7% (9/12) in the left circumflex coronary artery (LCX), and 75% (8/12) in the right coronary artery (RCA). The average strains in the long axis, radial, and circumferential directions (Strain_{SL, SC, SR} - Avg) in the three main coronaries were significantly different between the hypercholesterolemia group and control group (P<0.0001). In the three coronaries and their basal and mid segments, there were significant differences between LCX and LAD, and between LCX and RCA (P<0.0001). In conclusion, the application of STI for monitoring cardiac function in patients with hypercholesterolemia provides physicians with useful information related to hypercholesterolemia to achieve early diagnosis and effective treatment.

Strain Imaging Echocardiography: What Imaging Cardiologists Should Know

Despite recent advances in clinical imaging, echocardiography remains as the most accessi-ble and reliable noninvasive. Since knowledge of left ventricular systolic function remains so critically important in determining prognosis; every effort should be made to prevent subjective estimations. The advent of strain imaging echocardiography now offers a readily available and portable imaging tool that not only offers an objective characterization of myocardial dynamics; but also allows for early detection of subclinical left ventricular dysfunction. This review outlines the basic concepts of strain imaging to better understand the mechanism of myocardial function as well their applicability in the least common cardiac diagnosis among current clinical practice.

Speckle tracking analysis allows sensitive detection of stress cardiomyopathy in severe aneurysmal subarachnoid hemorrhage patients

PURPOSE

Stress cardiomyopathy is a common life-threatening complication after aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that left ventricular (LV) longitudinal strain alterations assessed with speckle tracking could identify early systolic function impairment.

METHODS

This was an observational single-center prospective pilot controlled study conducted in a neuro-intensive care unit. Forty-six patients with severe SAH with a World Federation of Neurological Surgeons grade (WFNS) ≥ III were included. Transthoracic echocardiography (TTE) was performed on day 1, day 3, and day 7 after the patient's admission. A cardiologist blinded to the patient's management analyzed the LV global longitudinal strain (GLS). The control group comprised normal subjects matched according to gender and age.

RESULTS

On day 1 median (25th-75th percentile) GLS was clearly impaired in SAH patients compared to controls [-16.7 (-18.7/-13.7) % versus -20 (-22/-19) %, p < 0.0001], whereas LVEF was preserved [65 (59-70) %]. GLS was severely impaired in patients with a WFNS score of V versus III-IV [-15.6 (-16.9/-12.3) % versus -17.8 (-20.6/-15.8) %, p = 0.008]. Seventeen (37 %) patients had a severe GLS alteration (>- 16 %). In these patients, GLS improved from day 1 [-12.4 (-14.8/-10.9) %] to last evaluation [-16.2 (-19/-14.6) %, p = 0.0007] in agreement with the natural evolution of stress cardiomyopathy.

CONCLUSIONS

On the basis of LV GLS assessment, we demonstrated for the first time that myocardial alteration compatible with a stress cardiomyopathy is detectable in up to 37 % of patients with severe SAH while LVEF is preserved. GLS could be used for sensitive detection of stress cardiomyopathy. This is critical because cardiac impairment remains a major cause of morbidity and mortality after SAH.

Detection of left atrial dysfunction with speckle tracking echocardiography

BACKGROUND

The aim of this study was to evaluate the relationship between the SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score and left ventricular end-diastolic pressure (LVEDP) measured with an invasive method and with speckle-tracking echocardiography (STE).

METHODS

The study included 124 patients who underwent cardiac catheterization. LVEDP values and coronary images were obtained for all patients. SYNTAX scores were calculated and separated into three tertiles (SYNTAX = 0, SYNTAX < 22, and SYNTAX > 22). Standard echocardiography and STE were performed on all the patients. Peak LA strain (LAs strain) in ventricular end-systole and LA strain during LA contraction (LAa strain) values were obtained with STE.

RESULTS

In univariate analysis, a strong correlation was observed between the SYNTAX score and LAs strain and a moderate correlation with LAa strain. A moderate correlation was also found between both LAs strain and LAa strain and LVEDP. In multiple regression analysis, LAs strain and LVEDP were observed to be independent predictors of SYNTAX score.

CONCLUSION

LAs strain and LVEDP were observed to be independent predictors of SYNTAX scores. The relationship between LAs strain, LVEDP, and SYNTAX score could be useful in clinical practice.

Nonalcoholic Steatohepatitis Score is an Independent Predictor of Right Ventricular Dysfunction in Patients with Nonalcoholic Fatty Liver Disease

OBJECTIVE

Nonalcoholic fatty liver disease (NAFLD) is associated with increased risk of cardiovascular disease and impaired left ventricular (LV) function, yet the impact of NAFLD on right ventricular (RV) function remains unclear. We investigate the RV functional properties in patients with NAFLD.

METHODS

Ninety consecutive patients with the diagnosis of biopsy-proven NAFLD and 45 age- and sex-matched controls were included. All patients underwent an echocardiographic examination. RV function was evaluated by two-dimensional (2D) speckle-tracking echocardiography (STE).

RESULTS

Mean fibrosis stage and nonalcoholic steatohepatitis (NASH) scores were 1.3 ± 1.1 and 5.2 ± 1.6, respectively. NAFLD patients displayed decreased RV function compared to controls. NAFLD patients with liver fibrosis (67 patients) had significantly lower RV function assessed by GLS (global longitudinal strain) compared to patients without liver fibrosis (18.9 ± 3.4% vs. 21.6 ± 2.3%, P < 0.001). NASH score ≥5 was associated with lower RV-GLS (18.9 ± 3.1% vs. 21.0 ± 3.4%, P = 0.006). NASH score inversely correlated with RV-GLS (r = -0.370, P < 0.001) such as patients with impaired RV-GLS (<19%) showed significantly higher NASH score compared to normal RV-GLS group (5.8 ± 1.4 vs. 4.8 ± 1.7, P = 0.009). Logistic regression analysis revealed that NASH score was an independent predictor of impaired RV function in patients with NAFLD.

CONCLUSIONS

Patients with NAFLD have impaired RV function. NASH score inversely correlates with RV-GLS and independently predicts impaired RV function in patients with NAFLD.

Differences in Left Ventricular Global Function and Mechanics in Paralympic Athletes with Cervical and Thoracic Spinal Cord Injuries

Following a spinal cord injury, there are changes in resting stroke volume (SV) and its response to exercise. The purpose of the following study was to characterize resting left ventricular structure, function, and mechanics in Paralympic athletes with tetraplegia (TETRA) and paraplegia (PARA) in an attempt to understand whether the alterations in SV are attributable to inherent dysfunction in the left ventricle. This retrospective study compared Paralympic athletes with a traumatic, chronic (>1 year post-injury), motor-complete spinal cord injury (American Spinal Injury Association Impairment Scale A-B). Eight male TETRA wheelchair rugby players (34 ± 5 years, C5-C7) and eight male PARA alpine skiers (35 ± 5 years, T4-L3) were included in the study. Echocardiography was performed in the left lateral decubitus position and indices of left ventricular structure, global diastolic and systolic function, and mechanics were derived from the average across three cardiac cycles. Blood pressure was measured in the supine and seated positions. All results are presented as TETRA vs. PARA. There was no difference in left ventricular dimensions between TETRA and PARA. Additionally, indices of global diastolic function were similar between groups including isovolumetric relaxation time, early (E) and late (A) transmitral filling velocities and their ratio (E/A). While ejection fraction was similar between TETRA and PARA (59 ± 4 % vs. 61 ± 7 %, p = 0.394), there was evidence of reduced global systolic function in TETRA including lower SV (62 ± 9 ml vs. 71 ± 6 ml, p = 0.016) and cardiac output (3.5 ± 0.6 L/min vs. 5.0 ± 0.9 L/min, p = 0.002). Despite this observation, several indices of systolic and diastolic mechanics were maintained in TETRA but attenuted in PARA including circumferential strain at the level of the papillary muscle (−23 ± 4% vs. −15 ± 6%, p = 0.010) and apex (−36 ± 10% vs. −23 ± 5%, p = 0.010) and their corresponding diastolic strain rates (papillary: 1.90 ± 0.63 s⁻¹ vs. 1.20 ± 0.51 s⁻¹, p = 0.028; apex: 3.03 ± 0.71 s⁻¹ vs. 1.99 ± 0.69 s⁻¹, p = 0.009). All blood pressures were lower in TETRA. The absence of an association between reduced global systolic function and mechanical dysfunction in either TETRA or PARA suggests any reductions in SV are likely attributed to impaired loading rather than inherent left ventricular dysfunction.

Early detection of cardiac dysfunction in the type 1 diabetic heart using speckle-tracking based strain imaging

Enhanced sensitivity in echocardiographic analyses may allow for early detection of changes in cardiac function beyond the detection limits of conventional echocardiographic analyses, particularly in a small animal model. The goal of this study was to compare conventional echocardiographic measurements and speckle-tracking based strain imaging analyses in a small animal model of type 1 diabetes mellitus. Conventional analyses revealed differences in ejection fraction, fractional shortening, cardiac output, and stroke volume in diabetic animals relative to controls at 6-weeks post-diabetic onset. In contrast, when assessing short- and long-axis speckle-tracking based strain analyses, diabetic mice showed changes in average systolic radial strain, radial strain rate, radial displacement, and radial velocity, as well as decreased circumferential and longitudinal strain rate, as early as 1-week post-diabetic onset and persisting throughout the diabetic study. Further, we performed regional analyses for the LV and found that the free wall region was affected in both the short- and long-axis when assessing radial dimension parameters. These changes began 1-week post-diabetic onset and remained throughout the progression of the disease. These findings demonstrate the use of speckle-tracking based strain as an approach to elucidate cardiac dysfunction from a global perspective, identifying left ventricular cardiac regions affected during the progression of type 1 diabetes mellitus earlier than contractile changes detected by conventional echocardiographic measurements.

Myocardial deformation imaging unmasks subtle left ventricular systolic dysfunction in asymptomatic and treatment-naïve HIV patients

BACKGROUND

Patients infected by the human immunodeficiency virus (HIV) and receiving highly active antiretroviral therapy have a higher incidence of cardiovascular disease than healthy subjects, but little is known about cardiac function in asymptomatic and treatment-naïve patients. We sought to study cardiac function in asymptomatic HIV-infected, treatment-naïve patients.

METHODS

We studied 41 HIV-infected and treatment-naïve patients and 20 age- and sex-matched healthy controls. Patients with cardiac symptoms, history of cardiac disease or NT-proBNP >100 pg/mL were excluded. We addressed cardiac function using standard echocardiography along with tissue Doppler (TDI) measurements, including strain/strain rate assessment.

RESULTS

Standard echocardiographic parameters did not differ between groups, except for transmitral E wave velocity (64.8 ± 14 cm/s in HIV vs 76.1 ± 10 cm/s in controls, p = 0.002). In contrast, TDI mitral and tricuspid annulus s velocity and all strain/strain rate measurements were significantly lower in HIV patients: s lateral, 10.2 ± 2.4/11.3 ± 0.7, p = 0.011; s septal, 8.1 ± 1.6/8.7 ± 0.8, p = 0.045; s tricuspid, 13.4 ± 2.3/14.9 ± 1.3, p = 0.002; strain/strain rate, septal (strain/strain rate, 15.1 ± 5.7/-0.9 ± 0.3, 25.3 ± 1.7/-1.9 ± 0.2, p < 0.001), anterior (16.7 ± 3/-1.0 ± 0.1, 26.7 ± 1.7/-1.9 ± 0.2, p < 0.001), lateral (16.0 ± 6/-1.0 ± 0.1, 27.5 ± 1.8/-2.2 ± 0.3, p < 0.001) and posterior (15.2 ± 5.8/-1.0 ± 0.2, 26.2 ± 1.8/-2.2 ± 0.3, p < 0.001) left ventricular wall.

CONCLUSIONS

HIV infection itself is accompanied by subclinical systolic dysfunction, not apparent to standard echocardiography that can be unmasked though using sensitive echocardiographic techniques.

Principles of transthoracic echocardiographic evaluation

Transthoracic echocardiography is the most widely used imaging test in cardiology. Although completely noninvasive, transthoracic echocardiography has a well-established role in the diagnosis of numerous cardiovascular diseases, and also provides critical qualitative and quantitative information on their prognosis and pathophysiological processes. The aim of this Review is to outline the broad principles of transthoracic echocardiography, including the traditional techniques of two-dimensional, colour, and spectral Doppler echocardiography, and newly developed advances including tissue Doppler, myocardial deformation imaging, torsion, stress echocardiography, contrast and three-dimensional echocardiography. The advantages and disadvantages, clinical application, prognostic value, and salient research findings of each modality are described. Advances in complex imaging techniques are expected to continue unabated, and this Review highlights technical improvements that will influence the diagnosis and improve our understanding of cardiovascular function and disease.

Effects of Bone Marrow Mononuclear Cells Delivered through a Graft Vessel for Patients with Previous Myocardial Infarction and Chronic Heart Failure: An Echocardiographic Study of Left Atrium Function

OBJECTIVES

The graft of stem cells to treat ischemic cardiomyopathy is popular in many clinical trials. The aim of this study was to evaluate the effectiveness of isolated coronary artery bypass graft combined with bone marrow mononuclear cells (BMMNC) delivered through the graft vessels to improve left atrium (LA) function of patients with previous myocardial infarction and chronic heart failure using echocardiography.

METHODS

Forty-two patients with previous myocardial infarction and chronic heart failure were randomly allocated to one of the two groups: coronary artery bypass graft (CABG) only (18 in CABG group) or CABG with BMMNC transplantation (24 in CABG + BMMNC group). Echocardiographic parameters were measured on two-dimensional (2D) imaging, three-dimensional imaging, 2D strain, and strain rate imaging, eight parameters were measured totally.

RESULTS

Postoperative LA global strain (LAGS) versus Preoperative LAGS were 24.875 ± 1.588% versus 14.250 ± 1.281% (P < 0.05) in CABG + BMMMNC group and 17.556 ± 1.834% versus 13.111 ± 1.479% (P < 0.05) in CABG group, LVEF was 49.083 ± 1.914% versus 36.042 ± 1.185% (P < 0.05) in CABG + BMMMNC group and 41.389 ± 2.210% versus 34.667 ± 1.369% (P < 0.05) in CABG group, and LA volume (LAV) was 15.651 ± 0.631 mL versus 23.894 ± 0.831 mL (P < 0.05) in CABG + BMMMNC group and 21.429 ± 0.707 mL versus 22.379 ± 0.959 mL (P < 0.05) in CABG group. LAGS, LVEF, and LAV were significantly improved postoperatively in both groups. The degree of the improvement was significantly different between the two groups with the CABG + BMMNC group improved more versus the group of CABG only (P < 0.05). Postoperative LVEDV and LVESV were significantly improved compared with those obtained prior to operation in CABG + BMMNC group (P < 0.05).

CONCLUSIONS

The improvement of LA function in CABG + BMMNC group is better than CABG group. 2D strain imaging is a more sensitive tool to evaluate LA function.

Right ventricular function in hypertrophic cardiomyopathy: A speckle tracking echocardiography study

Objective:

The aim of this study was to explore right ventricular (RV) mechanical function in patients with hypertrophic cardiomyopathy (HCM) by 2-D speckle tracking echocardiography (2-D-STE).

Methods:

Forty-three patients with HCM (mean age 48, 17 females) and 40 healthy subjects were consecutively included in this cross-sectional study. The diagnosis of HCM was based on the presence of typical clinical, electrocardiographic (ECG), and echocardiographic features. Patients with LV systolic impairment, significant valvular disease, history of coronary artery disease, hypertension, malignancy, and chronic obstructive pulmonary disease were excluded. Right and left ventricular (LV) function was assessed by tissue Doppler imaging (TDI) and 2-D-STE. Hypertrophic cardiomyopathy patients were divided into two groups according to ACC/ESC guidelines (LVOT gradient below and above 30 mm Hg). Student t-test was used to compare differences between groups. Non-parametric tests (Mann-Whitney U) were used in cases of abnormal distribution.

Results:

Hypertrophic cardiomyopathy patients had a significantly larger right atrium and RV diameters compared to controls. Mean pulmonary artery pressures (mPAB) were significantly higher in HCM patients (19.01±13.09 mm Hg vs. 8.40±4.50 mm Hg; p<0.001). Although RV Sm measure-ments were similar, RV strain measurements (-28.51±5.36% vs. -32.06±7.65%; p=0.016) were significantly lower in HCM patients. Left ventricular global longitudinal, radial, and circumferential strain values were also significantly different between the two groups (-20.50±3.58% vs. -24.12±3.40%; p<0.001, 38.18±12.67% vs. 44.80±10.15%; p=0.012, -21.94±4.28% vs. -23.91±3.95%; p=0.036 consecutively). Rotational movement of LV in each apical, mid-, and basal left ventricular segment was determined, and only mid-ventricular rotation of the HCM patients was more clockwise (-1.71±2.16 ° vs. 0.04±1.72 p<0.001). Although mPAP measurements were higher in HCM patients with significant LVOT obstruction (21.52±13.26 mm Hg vs. 12.31±10.53 mm Hg; p=0.049), none of the other TDI or 2-D-STE parameters was significantly different between groups.

Conclusion:

Speckle tracking echocardiography-derived right ventricular systolic function is impaired in HCM patients when compared with healthy subjects. However, RV systolic function is not affected form LVOT obstruction and left ventricular rotation dynamics in HCM patients.

Effect of left atrium volume on patients' prognosis following acute myocardial infarction

Evaluating left atrium volume is a good way to estimate prognosis in acute myocardial infarction patients because it indicates to time and severity of diastolic dysfunction and longer-term results of acute myocardial infarction. The present study aims at evaluating the effect of left atrium volume on patients' prognosis following acute myocardial infarction. This is a cohort study conducted on 100 patients who were admitted with acute myocardial infarction. They were studied for 9 months and their one-month mortality rate was evaluated. The patients were studied considering demographic factors, risk factors, mechanical and arrhythmic complications and echocardiography indexes such as systolic and diastolic functions and left atrium volume. It was seen that mortality (27.3%, 6.22) in patients with atrium index > 32 mL m(-2) is more than cases with lower atrium index (1.3%, 1.78) (p = 0.001). There was not any meaningful difference in mortality rate of the patients considering age and gender (p > 0.05). This study indicated to lack of any meaningful difference in patients' mortality rate in terms of hypertension, diabetes, smoking and dyslipidemia. But, mortality rate was significantly higher in MI as a result of elevated-ST, diastolic dysfunction, restrictive pattern, ejection fraction of left atrium < 40%, left atrium volume index > 32 mL m(-2). High volume left atrium independently refers to bad prognosis in patients with acute myocardial infarction which is confirmed with outcome clinical predictors and common echocardiography indexes even following modification.

Asymptomatic left ventricular dysfunction with long-term clozapine treatment for schizophrenia: a multicentre cross-sectional cohort study

Objectives

Patients with schizophrenia treated with clozapine are at risk of acute myocarditis and dilated cardiomyopathy. However, there are no data on the prevalence of subclinical cardiomyopathy or its associations.

Methods

100 consecutive patients with schizophrenia treated with clozapine for >1 year and without a history of cardiac pathology (group 1), 21 controls with a history of schizophrenia treated with non-clozapine antipsychotics for >1 year (group 2) and 20 controls without schizophrenia (group 3) were studied. Comprehensive evaluation by clinical examination, ECG, transthoracic echocardiography including left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) and biochemical profiles were performed.

Results

Patients with schizophrenia were of similar age, but had higher body mass index (BMI), rates of smoking and hyperlipidaemia than controls. Patients with schizophrenia had received clozapine or non-clozapine antipsychotics for a mean duration of 6.8±5.3 and 9.7±6.1 years, respectively. Patients taking clozapine demonstrated globally impaired LVEF (58.3%: group 1 vs 62.2%: group 2 vs 64.8%: group 3, p<0.001) and GLS (−16.7%: group 1 vs −18.6%: group 2 vs −20.2%: group 3, p<0.001). Moreover, LVEF was <50% in 9/100 (9%) patients receiving clozapine and in non-clozapine schizophrenia patients or healthy controls, but this was not statistically significantly different (analysis of covariance, p=0.19). Univariate analysis in patients taking clozapine found that impaired LV was not predicted by high-sensitivity troponin T, but was associated with features of the metabolic syndrome (including increased triglycerides, low high-density lipoprotein cholesterol (HDL-C), high-sensitivity C reactive protein and BMI), elevated neutrophil count, elevated heart rate, smoking and N-terminal probrain natriuretic peptide. In patients taking clozapine, multivariable analysis identified elevated neutrophil count and low HDL-C as the only independent predictors of impaired GLS.

Conclusions

Asymptomatic mild LV impairment is common in patients with schizophrenia receiving long-term clozapine treatment and is associated with neutrophilia and low HDL-C.

A new twist on an old idea: a two-dimensional speckle tracking assessment of cyclosporine as a therapeutic alternative for heart failure with preserved ejection fraction

We recently reported that mitochondrial dysfunction, characterized by increased mitochondrial permeability transition (MPT), was present in a translational swine model of heart failure with preserved ejection fraction (HFpEF). Cyclophilin D is a key component of the MPT pore, therefore, the purpose of this study was to test the efficacy of a novel cyclosporine (CsA) dosing scheme as a therapeutic alternative for HFpEF. Computed tomography (CT), two‐dimensional speckle tracking two‐dimensional speckle tracking (2DST), and invasive hemodynamics were used to evaluate cardiac function. CT imaging showed 14 weeks of CsA treatment caused eccentric myocardial remodeling (contrasting concentric remodeling in untreated HF animals) and elevated systemic pressures. 2DST detected left ventricular (LV) mechanics associated with systolic and diastolic dysfunction prior to the onset of significantly increased LV end diastolic pressure including: (1) decreased systolic apical rotation rate, longitudinal displacement, and longitudinal/radial/circumferential strain; (2) decreased early diastolic untwisting and longitudinal strain rate; and (3) increased late diastolic radial/circumferential mitral strain rate. LV mechanics associated with systolic and diastolic impairment was enhanced to a greater extent than seen in untreated HF animals following CsA treatment. In conclusion, CsA treatment accelerated the development of heart failure, including dilatory LV remodeling and impaired systolic and diastolic mechanics. Although our findings do not support CsA as a viable therapy for HFpEF, 2DST was effective in differentiating between progressive gradations of developing HF and detecting diastolic impairment prior to the development of overt diastolic dysfunction.

We recently reported that mitochondrial dysfunction, characterized by increased mitochondrial permeability transition (MPT), was present in a translational swine model of heart failure with preserved ejection fraction (HFpEF). Cyclophilin D is a key component of the MPT pore, therefore, the purpose of this study was to test the efficacy of a novel cyclosporine (CsA) dosing scheme as a therapeutic alternative for HFpEF. CsA treatment accelerated the development of heart failure, including dilatory LV remodeling and impaired systolic and diastolic mechanics. Although our findings do not support CsA as a viable therapy for HFpEF, 2DST was effective in differentiating between progressive gradations of developing HF and detecting diastolic impairment prior to the development of overt diastolic dysfunction.

N-Terminal proBNP Levels and Tissue Doppler Echocardiography in Acute Rheumatic Carditis

Background. Rheumatic heart disease (RHD) is a leading cause of heart failure in children and young adults worldwide. B-type natriuretic peptide (BNP) is a useful marker of critical pediatric heart disease, and its N-terminal peptide, NT-proBNP, is elevated in congenital and acquired heart disease in children. Aim. To measure NT-proBNP levels as a marker of carditis in children with acute rheumatic carditis, as compared to children with quiescent RHD and healthy controls. Methods. 16 children with acute rheumatic carditis, 33 children with quiescent RHD, and a cohort of 30 healthy children were studied. Transthoracic echocardiography was performed to assess valve and cardiac function. Tissue Doppler echocardiography was performed for E/E′ (ratio between mitral inflow E wave and lateral mitral annulus E′ wave) and systolic strain. Results. NT-proBNP levels were significantly higher in children with acute rheumatic carditis and dropped with its resolution. Strain and E/E′ values were comparable among the three groups. Conclusion. NT-proBNP is significantly elevated in children with acute rheumatic carditis in the acute stage compared to children with quiescent RHD and healthy subjects, in the presence of comparable echocardiographic indices of LV systolic and diastolic function.

Imaging techniques for cardiac strain and deformation: comparison of echocardiography, cardiac magnetic resonance and cardiac computed tomography

Myocardial function assessment is essential for determining the health of the myocardium. Global assessment of myocardial function is widely performed (by estimating the ejection fraction), but many common cardiac diseases initially affect the myocardium on a regional, rather than global basis. Regional myocardial wall motion can be quantified using myocardial strain analysis (a normalized measure of deformation). Myocardial strain can be measured in terms of three normal strains (longitudinal strain, radial strain and circumferential) and six shear strains. Cardiac MRI (cMRI) is usually considered the reference standard for measurement of myocardial strain. The most common cMRI method, termed tagged cMRI, allows full, 3D assessment of regional strain. However, due to its complexity and lengthy times for analysis, tagged cMRI is not usually used outside of academic centers. Tagged cMRI is also primarily used only in research studies. Echocardiography combined with tissue Doppler imaging or a speckle tracking technique is now widely available in the clinical setting. Myocardial strain measurement by echocardiography shows reasonable agreement with cMRI. Limited standardization and differences between vendors represent current limitations of the technique. Cardiac computed tomography (CCT) is the newest and most rapidly growing modality for noninvasive imaging of the heart. While CCT studies are most commonly applied to assess the coronary arteries, CCT is easily adapted to provide functional information for both the left and right ventricles. New methods for CCT assessment of regional myocardial function are being developed. This review outlines the current literature on imaging techniques related to cardiac strain analysis and discusses the strengths and weaknesses of various methods for myocardial strain analysis.

Sex-specific assessment of reduced coronary sinus flow in non-hypertensive patients with coronary artery disease at rest

BACKGROUND

Access to data on the coronary flow in the coronary sinus (CS) can aid in the diagnosis of coronary artery disease (CAD). We tested the hypothesis that assessing the CS flow by transthoracic Doppler echocardiography (TTE) at rest can detect coronary artery stenosis in non-hypertensive patients.

METHODS

The antegrade phase of coronary flow in the CS was analyzed and compared in 140 male and 135 female non-hypertensive subjects who had all undergone coronary angiography.

RESULTS

There were statistically significant differences noted between males and females for the CS flow both in normal subjects and patients with CAD. Compared with normal subjects, patients with CAD had significantly lower blood flow in the CS both in males (196.6±174.31 vs. 367.65±168.04 ml/min, P<0.01) and females (183.04±65.46 vs. 244.13±135.43 ml/min P<0.01). For males, the diagnostic sensitivity, specificity, and accuracy of the cutoff value of the CS flow (206 ml/min) for predicting a significant coronary artery stenosis (>70%) were 91.67%, 81.25%, and 85.71%, respectively. For females, those of the cutoff value of the CS flow (195 ml/min) were 85.71%, 75%, and 80%, respectively.

CONCLUSION

TTE can effectively detect coronary hemodynamically significant stenosis in non-hypertensive male and female patients at different cutoff values.