Can global longitudinal strain predict reduced left ventricular ejection fraction in daily echocardiographic practice?

Quantitative assessment of left ventricular myocardial work in patients with different types of atrial fibrillation by non-invasive pressure-strain loop technique

OBJECTIVE

This study aimed to analyze myocardial work in patients with atrial fibrillation (AF) using a noninvasive pressure strain loop (PSL) technique to provide a basis for the quantitative assessment of left ventricular (LV) systolic function.

METHODS

LV myocardial work of 107 AF patients (56 with paroxysmal atrial fibrillation and 51 with persistent atrial fibrillation) and 55 healthy individuals were assessed by the noninvasive PSL and then compared.

RESULTS

Global longitudinal strain (GLS) in absolute values, global work index (GWI), global constructive work (GCW), and global work efficiency (GWE) were significantly lower in the AF group than control group, whereas peak strain dispersion (PSD) and global wasted work (GWW) were significantly higher (P < .05). Further subdivision according to the AF type revealed that, compared with the controls, GLS in absolute values and GWE decreased significantly; PSD and GWW increased significantly in the paroxysmal AF group (P < .05). Nevertheless, GWI and GCW were not significantly different between paroxysmal AF and control groups (P > .05). Compared to paroxysmal AF, persistent AF induced a further decrease in absolute GLS and GWE and a further increase in GWW (P < .05), but PSD did not increase further (P > .05). Multiple linear regression analysis showed that GWI and GCW were independently associated with systolic blood pressure. GWW was associated with types of AF and left atrial volume index (LAVI). GWE was correlated with age, types of AF, disease duration, and LAVI. Receiver operating characteristic curve analysis showed that the area under the curve predicting myocardial injury was higher for GWE and GWW than for GLS (area under the curve:  .880,  .846, and  .821, respectively).

CONCLUSIONS

Non-invasive PSL can quantitatively assess LV systolic function in patients with different kinds of AF and detect early subclinical myocardial injury in patients with paroxysmal AF. GWE and GWW outperform GLS and LV ejection fraction when assessing myocardial injury. Systolic blood pressure, type of AF, LVAI, disease duration, and age may be associated with myocardial injury in patients with AF.

Combined effect of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease

Sedentary behavior has been associated with poor adherence to treatment in patients with coronary artery disease. Low left ventricular ejection fraction and obesity have been separately linked to increased sedentary behavior in patients with coronary artery disease. However, the combined effect of low left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease has not been thoroughly investigated. Therefore, this study aimed to examine the combined influence of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease. This descriptive cross-sectional study enrolled 200 inpatients aged ≥ 20 years who were diagnosed with coronary artery disease at a tertiary hospital in Korea between March and August 2022. Data were collected using structured questionnaires, and multivariate logistic regression analysis was performed to determine the combined effect of left ventricular ejection fraction and obesity on sedentary behavior in patients with coronary artery disease. Among the 111 patients with sedentary behavior, 38 (34.2%) had both low left ventricular ejection fraction and obesity, whereas only 11 (12.4%) of the 89 patients without sedentary behavior had both low left ventricular ejection fraction and obesity. In multivariate logistic regression analysis, patients with coronary artery disease who had both low left ventricular ejection fraction and obesity had the highest risk of sedentary behavior compared to those without either low left ventricular ejection fraction or obesity (odds ratio = 13.98, 95% confidence interval = 5.19-37.69, P < .001). The co-existence of low left ventricular ejection fraction and obesity in patients with coronary artery disease may be associated with sedentary behavior. Therefore, evaluating both left ventricular ejection fraction and obesity when assessing sedentary behavior in patients with coronary artery disease may be valuable in implementing patient-centered approaches for the secondary prevention and management of sedentary behavior in patients with coronary artery disease. However, further prospective cohort studies with larger sample sizes are required to establish causal relationships and explore interventions to mitigate sedentary behavior in this population.

Comparison between Visual Assessment and Longitudinal Strain during Dobutamine Stress Echocardiography

Background

The relationship between visual assessment and longitudinal strain during dobutamine stress echocardiography (DSE) remains poorly investigated. This study assessed wall motion segments visually graded as normokinetic, hypokinetic, and akinetic at baseline and the peak of DSE and compared with longitudinal strain between segments with and without induced impaired contractility and improved contractility during DSE.

Methods

This study included 112 patients examined by DSE, consisting of 58 patients referred for diagnostic study and 54 patients referred for viability study. Regional left ventricular (LV) contractility was assessed visually and longitudinal strain was measured using echocardiography transthoracic.

Results

At baseline, the strain of LV segments was -16.33 ± 6.26 in visually normokinetic, 13.05 ± 6.44 in visually hypokinetic, and -8.46 ± 5.69 in visually akinetic segments. During peak dose, the strain of LV segments was -15.37 ± 6.89 in visually normokinetic, -11.37 ± 5.11 in visually hypokinetic, and -7.37 ± 3.92 in visually akinetic segments. In segments with visually observed impaired contractility, the median longitudinal strain was significantly lower than in segments without impaired contractility. For segments with visually observed improved contractility, the median longitudinal strain was significantly higher than for segments without improved contractility. In diagnostic study, sensitivity of visual assessment for absolute decrease of >2% longitudinal strain was 77%, respectively. In the viability study, the sensitivity was 82% for an absolute decrease of ≥2% longitudinal strain.

Conclusions

There is good association between strain analysis value and visually assessed wall motion contractility.

2D speckle-tracking echocardiography as a prognostic imaging modality for COVID-19 adverse outcomes

2D speckle-tracking echocardiography (2D-STE) has been used to assess cardiac recovery during the COVID-19 patient follow-ups within the pandemic. The novel role of STE in predicting adverse outcomes of COVID-19 has received attention due to its high sensitivity in identifying subclinical myocardial dysfunction. We reviewed the studies on using 2D-STE to assess COVID-19 prognosis. A literature search was conducted on PubMed and Scopus for eligible articles, 24 of which discussed using prognostic 2D-STE for COVID-19 patients. 2D-STE predicts cardiovascular impairments more rapidly and precisely than conventional echocardiography. The 2D-STE technique presents an independent prognostic factor in COVID-19 infection. 2D-STE could be considered a time-efficient and accurate risk predictor of all-cause mortality in COVID-19 patients.

Evaluation of patients with high burden of premature ventricular contractions by comprehensive transthoracic echocardiography

Background

The prevalence and prognosis of premature ventricular contractions (PVCs) among individuals without structural heart disease are uncertain. Standard transthoracic echocardiography is a common method in evaluation of underlying cardiovascular disease and is recommended as a diagnostic method in PVC patients. However, it is unclear whether comprehensive echocardiographic examination can identify pathological findings in PVC patients with a normal standard echocardiogram.

Method

We included forty consecutive patients with a high PVC burden (>10,000 PVCs/day) and normal findings at a standard echocardiogram and exercise test. All subjects were investigated by a comprehensive echocardiographic examination using parameters usually not included in a routine work-up. We compared the results with 22 age and sex-matched controls.

Results

In six additional parameters–global longitudinal strain, right ventricular strain, septal-lateral delay, ventricular-arterial coupling, integrated backscatter and left atrial activation time–a statistically significant difference was shown between PVC patients and controls. Among these parameters, global longitudinal strain had a high reliability between operators.

Conclusions

Despite normal findings at standard echocardiography, the PVC group showed signs of impaired heart function when more comprehensive echocardiography parameters were used.

Could strain echocardiography help to assess systolic function in critically ill COVID-19 patients?

Strain echocardiography enables the automatic quantification of the global longitudinal strain (GLS), which is a direct measure of ventricular shortening during systole. In the current context of overwhelmed ICUs and clinician shortage, GLS has the advantage to be quick and easy to measure by non-experts. However, little is known regarding its value to assess bi-ventricular systolic function in critically ill COVID-19 patients. Therefore, we designed a study to compare right and left ventricular GLS with classic echo-Doppler indices of systolic function, namely the ejection fraction for the left ventricle (LVEF) and the fractional area change (FAC), the tricuspid annular plane systolic excursion (TAPSE), and the tissue Doppler velocity of the basal free lateral wall (S’) for the right ventricle. Eighty transthoracic echocardiographic evaluations done in 30 ICU patients with COVID-19 were analyzed. We observed a fair relationship (r = 0.73, p < 0.01) between LVEF and left ventricular GLS. The GLS cut-off value of − 22% identified a LVEF < 50% with a sensitivity of 63% and a specificity of 80%. All patients with a GLS > − 17% had a LVEF < 50%. Although statistically significant, relationships between FAC (r = 0.41, p < 0.01), TAPSE (r = 0.26, p < 0.05) and right ventricular GLS were weak. S’ was not correlated with right ventricular GLS. In conclusion, left ventricular GLS was useful to assess left ventricular systolic function. However, right ventricular GLS was poorly correlated with FAC, TAPSE and S’. Further studies are needed to clarify what is the best method to assess right ventricular systolic function in ICU patients with COVID-19.

Echocardiography in Confirmed and Highly Suspected Symptomatic COVID-19 Patients and Its Impact on Treatment Change

Background

COVID-19 interacts at multiple levels with the cardiovascular system. The prognosis of COVID-19 infection is known to be worse for patients with underlying cardiovascular diseases. Furthermore, the virus is responsible for many cardiovascular complications. Myocardial injury may affect up to 20% of the critically ill patients. However, echocardiography's impact on the management of patients affected by COVID-19 remains unknown.

Objectives

To explore echocardiography's impact on the management of COVID-19 patients.

Methods

This study was conducted from March 24^th to April 14^th, 2020, in a single center at Adolphe de Rothschild Foundation Hospital, Paris, France. All consecutive inpatients with laboratory and/or CT COVID-19 diagnosis were included in this study. Patients' characteristics (clinical, biological, and imaging) and treatment change induced by echocardiography were collected and analyzed. Patients with and without treatment change induced by echocardiography were compared.

Results

A total of 56 echocardiographies in 42 patients with highly suspected or confirmed COVID-19 were included in the final analyses. The median age was 66 (IQR 60.5-74). Echocardiography induced a treatment change in 9 cases (16%). The analyzed clinical data were not associated with any treatment change induced by echocardiography. D-dimer and Troponin levels were the only biological predictors of the induced treatment change. On echocardiography, higher systolic pulmonary arterial pressure and documented cardiac thrombi were associated with treatment changes in these patients.

Conclusions

Echocardiography may be useful for the management of selected COVID-19 patients, especially those with elevated D-Dimer and Troponin levels, in up to 16% of patients.

Correlation between global longitudinal strain and SYNTAX score in coronary artery disease evaluation

BACKGROUND

Speckle tracking echocardiography may allow the evaluation of myocardial systolic and diastolic dynamics across different physiologic and pathologic conditions beyond traditional echocardiographic techniques. The use of STE longitudinal strain in identification and risk stratification of CAD has good reproducibility and accuracy. The study aims to detect the relationship between SYNTAX score and global longitudinal peak systolic strain (GLPSS) in patients undergoing coronary angiography, with no history of myocardial infarction.

RESULTS

The study included 70 symptomatic patients suspected to have chronic coronary syndrome aging 20-80 years (excluding those with significant structural heart disease). All patients underwent clinical evaluation, surface ECG, laboratory assessment, transthoracic echocardiographic (TTE), color TDI tracings, two-dimensional speckle tracking, and conventional coronary angiography with SYNTAX score calculation. Patients were divided into 3 groups based on the results of the coronary angiogram: normal CAD on angiogram (n = 10, control group), low SS (n = 25, SS < 22), and high SS (n = 35, SS ≥ 22). The mean age was 55 ± 9.6 years; 54% were males; two third of patients were hypertensive; 52% were diabetic; high percentage of high syntax score were noticed among males, diabetic patients, and smokers; and also low mean of GLS was noticed among diabetic patients and smokers. There was a statistically significant positive correlation between syntax score and each of LVEDD and LVESD and, on the other hand, statistically significant negative correlation between syntax score and each of E/A, GLS, AP2LS, AP3LS, and AP4LS was noticed. Peak GLS cutoff value of 17.8 and 16.5 showed 84% and 93% sensitivity and 70% and 91% specificity to detect high and low syntax score, respectively.

CONCLUSION

2D longitudinal strain analysis has incremental diagnostic value over visual assessment during echocardiography in predicting significant coronary artery disease; GLS may offer a potential sensitive tool to detect significant CAD.

Left Ventricular End Diastolic Volume and Ejection Fraction Calculation: Correlation between Three Echocardiographic Methods

Background

Left ventricular ejection fraction (LVEF) and end diastolic volume (EDV) are measured using Simpson's biplane (SB), 3-dimensional method (3DE), and speckle tracking (STE). Comparisons between methods in routine practice are limited. Our purpose was to compare and to determine the correlations between these three methods in clinical setting.

Methods

LVEF and EDV were measured by three methods in 474 consecutive patients and compared using multiple Bland–Altman (BA) plots. The correlations (R) between methods were calculated.

Results

Median (IQR) LVEF_SB, LVEF_STE, and LVEF_3DE were 63.0% (60–69)%, 61% (57–65)%, and 62% (57–68)%. Median (IQR) EDV_SB, EDV_STE, and EDV_3DE were 85 ml (71–106) ml, 82 ml (69–100) ml, and 73 ml (59–89) ml. R between LVEF_SB and LVEF_3DE was 0.65 when echogenicity was good and 0.43 when poor. R for EDV_SB and EDV_3DE was 0.75 when echogenicity was good and 0.45 when poor. On BA analysis, biases were acceptable (<3.5% for LVEF) but limits of agreement (LOA) were large: 95% of the differences were between −15.4% and +18.8% for LVEF as evaluated by SB in comparison with 3DE, with a bias of 1.7%. In the comparison EDV_SB and EDV_3DE, the bias was 14 ml and the LOA were between −24 ml and +53 ml. On linear regressions, LVEF_3DE = 17.92 + 0.69 LVEF_SB and EDV_3DE = 18.94 + 0.63 EDV_SB.

Conclusions

The three methods were feasible and led to acceptable bias but large LOA. Although these methods are not interchangeable, our results allow 3DE value prediction from SB, the most commonly used method.

Left Ventricular Strain and Rotation in Patients with Dilated Cardiomyopathy and Severe Systolic Dysfunction

INTRODUCTION

In dilated cardiomyopathy (DCM) left ventricular (LV) strain and twist are significantly decreased. However, the rate of attenuation has not been investigated well in patients with varying degrees of systolic dysfunction.

AIM

The present study aimed to investigate the relationship between LV deformational and rotational mechanics and conventional and tissue Doppler imaging (TDI) parameters, and to search for a constellation of findings distinguishing patients with severe systolic dysfunction (SSD) in DCM.

METHODS

Fifty-two patients with heart failure NYHA class III-IV and ejection fraction (EF) ≤45% were prospectively enrolled (mean age 61.8 ± 13.4 years; 36 males, 69%). Severe systolic LV dysfunction was considered as EF <30%. Echocardiography with 2D-speckle tracking analysis was performed.

RESULTS

The relationships of global longitudinal strain (GLS) with EF, circumferential strain at mid-level (CSmid), and systolic medial mitral annulus velocity were strong (r = -0.53, 0.67, and -0.56, respectively, p < 0.0001 for all). A good correlation was found between CSmid and EF (r = -0.50, p < 0.0001). There were weak correlations between basal endocardial rotation (BRendo) and EF and CSmid. Multiple regression analysis found GLS (p < 0.0001) and BRendo (p = 0.04) to be predictors of the change of EF. In ROC curve analysis, the cut-off values of GLS -7.2% (AUC 0.81, p < 0.0001), CSmid -7.5% (AUC 0.76, p = 0.002), and BRendo -2.43° (AUC 0.68, p = 0.03) identified SSD.

CONCLUSIONS

Parameters of LV mechanics were related to conventional and TDI systolic parameters in patients with DCM. The degree of alterations of LV longitudinal and circumferential deformation and basal rotation may identify patients with SSD and a higher risk, and may help in therapeutic decision making.

CT-derived left ventricular global strain: a head-to-head comparison with speckle tracking echocardiography

We assessed CT-derived left ventricular strain in a cohort of patients referred for transcatheter aortic valve implantation (TAVI) and validated it against 2 dimensional speckle tracking echocardiography as the gold standard. 65 consecutive patients with symptomatic aortic valve stenosis referred for CT imaging prior to TAVI were included in this analysis. For all patients, retrospectively ECG-gated multi-phase functional CT data sets acquired with identical reconstruction parameters were available. All data sets were acquired using a third generation dual source system. In all patients, multiphase reconstructions in increments of 10% of the cardiac cycle were rendered (slice thickness 0.75, increment 0.5 mm, medium smooth reconstruction kernel) and transferred to a dedicated workstation (Ziostation2, Ziosoft Inc., Tokyo, Japan). Additional functional reconstructions for dynamic assessment and quantification of strain were processed. Multiplanar reconstructions (MPR) of the left ventricle similar to standard echocardiographic 4, 2 and apical 3 chamber views were rendered in CT. Similar to echocardiographic longitudinal strain, the perimeter of the left ventricle was manually traced within the myocardium and peak maximal shortening as a parameter representing longitudinal strain was calculated for each view and averaged to obtain a marker for global longitudinal strain (CT perimeter-derived strain). Furthermore, for quantification of 3-dimensional strain, endocardial and epicardial borders of myocardium were marked in six short axis views and peak maximum 3- dimensional strain of the myocardium was calculated in standard six basal, six mid and four apical segments. 3-dimensional strain values of the 16 standard segments as well as perimeter-derived strain values in the three standard windows were averaged to obtain global strain. Echocardiography was performed in all patients before CT data acquisition. Digital loops were acquired from three apical views (four-, two-, and three chamber views). For assessment of 2 dimensional global longitudinal strain (GLS), recordings were processed with acoustic-tracking software allowing offline semiautomated speckle-based strain analyses. The mean age of all 65 patients was 81 ± 5 years. The mean echocardiographic ejection fraction and mean echocardiographic GLS were 50 ± 12% and -13.6 ± 4.5%, respectively. The mean CT-derived peak 3-dimensional global strain and mean peak strain derived by perimeter was 43.2 ± 13.5% and -11.2 ± 3.5%, respectively. Both CTderived global 3D-strain and perimeter derived strain showed a significant correlation to GLS derived by echocardiography (r = -0.8, p < 0.0001 for 3D strain and r = 0.71, p < 0.0001 for perimeter-derived strain). Bland-Altman analysis showed a systematic underestimation (i. e. worse strain values) of CT perimeter-derived strain compared to GLS by echocardiography (mean difference -2.4% with 95% limits of agreement between 4% to -9%). ROC Curve analysis assuming a normal GLS when less than -18% showed that a CT-derived peak 3-dimensional global strain cut-off-value of 45% has a sensitivity of 91% and a specificity of 60% for detecting normal left ventricular strain (AUC 0.81, p = 0.001). For CT perimeter-derived strain, a cut-off value of -12%-assuming a normal echocardiographic GLS when less than -18%-achieved a sensitivity of 82% and a specificity of 61% (AUC of 0.82, p = 0.001) for detecting abnormal left ventricular strain. Using dedicated software, assessment of CT-derived left ventricular strain is feasible and comparable to strain derived by echocardiographic 2 dimensional speckle tracking.

Is echocardiography valid and reproducible in patients with atrial fibrillation? A systematic review

Aims

Echocardiography is vital in the routine assessment and management of atrial fibrillation (AF). We performed a systematic review of the validity and reproducibility of echocardiographic left ventricular systolic and diastolic function in AF, and optimal acquisition methods.

Methods and results

Online databases were searched for studies in patients with AF at the time of echocardiography (1960 to August 2015), prospectively registered with PROSPERO (CRD42015025297). The systematic review included 32 studies from 3 066 search results (1 968 patients with AF). Average age was 67 years, 33% were women, mean LVEF 53% (±10%), and average E/e’ 11.7 (±2.7). Data on the validity and reproducibility of systolic indices were extremely limited. In contrast, diastolic parameters demonstrated correlation with invasive filling pressure and adequate reproducibility: E/e’ (n = 444) r = 0.47 to 0.79; IVRT (n = 177) r = –0.70 to –0.95; E/Vp` (n = 55) r = 0.63 and 0.65; pulmonary vein diastolic flow (n = 67) r = –0.80 and –0.91. Elevated E/e’ (>15) was associated with functional capacity, quality of life, and impaired prognosis. For optimal acquisition in AF patients, cardiac cycles with controlled heart rate (<100 beats/min) and similar preceding and pre-preceding RR intervals are required. Cardiac cycle length and equivalence were more important than the number of beats averaged.

Conclusion

With careful selection of appropriate cardiac cycles, echocardiography is a valid tool to identify diastolic dysfunction in AF, and E/e’ is an independent marker of clinical status and adverse prognosis. However, data on systolic function was extremely limited and requires further prospective study and assessment of variability in clinical practice.

Global Longitudinal Strain and Strain Rate in Type Two Diabetes Patients with Chronic Heart Failure: Relevance to Osteoprotegerin

BACKGROUND

Biomechanical stress and inflammatory biomarkers relate to global contractility dysfunction; however, adding these biomarkers into a risk model constructed on clinical data does not improve its prediction value in chronic heart failure (CHF).

AIM

The aim of this study was to evaluate whether biomarkers predict declining of left ventricular global contractility function in diabetic patients with ischemia-induced CHF.

PATIENTS AND METHODS

The study retrospectively evolved 54 diabetic patients who had systolic or diastolic ischemia-induced CHF that was defined as left-ventricular ejection fraction (LVEF) ≤45% or 46-55% respectively assessed by quantitative echocardiography and other conventional criteria according to current clinical guidelines. Two-dimensional transthoracic echocardiography and tissue Doppler imaging were performed according to a conventional method. Radial, longitudinal, and circumferential strain and strain rate values were obtained by speckle-tracking Imaging analysis of both LV short axis and long axis views. Serum adiponectin, NT-pro brain natriuretic peptide (BNP), osteoprotegerin, and hs- C-reactive protein (CRP) were determined at baseline by ELISA.

RESULTS

We found lower global longitudinal strain and strain rate in diabetic patients with LVEF <45% than these in diabetic patients that did not have LVEF (Р=0.001 for all cases). Multivariate logistic regression analysis showed that NT-proBNP (r=0.432; P=0.001 and r=0.402; P=0.001, respectively), osteoprotegerin (r=0.422; P=0.001 and r=0.401; P=0.001, respectively), hs-CRP (r=0.408; P=0.001 and r=0.404; P=0.001, respectively) were independently inversely associated with global longitudinal strain and strain rate in CHF patients.

CONCLUSION

We suggest that osteoprotegerin may be useful in improving the NT-proBNP based model as predictor of decreased global contractility function in diabetic patients with CHF.

The value of right ventricular longitudinal strain in the evaluation of adult patients with repaired tetralogy of Fallot: a new tool for a contemporary challenge

OBJECTIVE

The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients.

METHODS

Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method.

RESULTS

In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=-0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (β=-0.72, 95% confidence interval -1.41, -0.15) and left ventricular ejection fraction (β=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was -17.0%.

CONCLUSIONS

Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.

Reproducibility and experience dependence of echocardiographic indices of left ventricular function: Side-by-side comparison of global longitudinal strain and ejection fraction

BACKGROUND

Although left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) are recommended by the current echocardiographic chamber quantification guidelines, these measurements are not performed routinely. Because EF measurements rely on manual tracing of LV boundaries, and are subject to inter-reader variability and experience dependence, we hypothesized that semiautomated GLS measurements using speckle tracking would be more reproducible and less experience-dependent.

METHODS

Images from 30 patients were analyzed to obtain biplane EF using manual tracing. GLS was measured in three long-axis views using EchoInsight software (Epsilon Imaging) that automatically detects LV endocardial boundary, which is edited manually as necessary and is then automatically tracked throughout the cardiac cycle. All measurements were performed by an expert echocardiographer and three first-year cardiology fellows.

RESULTS

Semiautomated GLS analysis showed excellent correlation (r=.98) and small bias (-1.0±13% of measured value) between the experienced and less experienced readers, superior to EF (r=.91, bias 7.3±16%). Also, in repeated measurements, GLS showed higher intra-class correlation (ICC=.98) than EF (ICC=.89). Additionally, GLS analysis required ~1 minute per patient, while biplane EF measurements took twice as long.

CONCLUSIONS

Semiautomated GLS measurements are fast, less experience-dependent, and more reproducible than conventional EF measurements. This is probably because, irrespective of experience, the readers' choice of boundary position varies less when asked to refine the automated detection than to draw borders without initial clues. This technique may facilitate the workflow of a busy laboratory and make a step forward toward incorporating quantitative analysis into everyday echocardiography practice.