Usefulness of layer-specific strain in diagnosis of coronary artery disease in patients with stable angina pectoris

Resting segmental speckle tracking strain and strain rate in stable coronary artery disease and revascularized myocardial infarction

Patients with acute coronary artery disease (CAD) exhibit reduced global and regional strain and strain rate (S/SR). However, knowledge about segmental S/SR in stable CAD patients is still limited. This study aimed to investigate whether resting segmental S/SR measurements differ in patients with chronic chest pain who have normal coronary arteries or stenotic coronary arteries, and to compare these measurements to those in patients with revascularized myocardial infarction (MI). We prospectively enrolled 510 patients with chronic chest pain referred for coronary computed tomography angiography (CCTA) and 102 patients revascularized after MI. All participants underwent transthoracic echocardiography featuring S/SR analysis. In addition to the patients with MI, patients with suspected CAD based on CCTA findings subsequently underwent invasive coronary angiography (CAG). We assessed global longitudinal strain (GLS) and averaged segmental peak longitudinal strain during systole (PLS), peak systolic strain rate (SRs), peak early diastolic strain rate (SRe), and post systolic shortening (PSS). We also determined functionally reduced segment percentages using differing S/SR cut-off values. There were significant disparities in all average segmental S/SR metrics between the No-CAD and MI groups. SRe was the only S/SR metric that differed significantly between the No-CAD and PCI groups. Differences in SRe, PLS and GLS measurements were observed between the No-CAD and CABG groups. The proportion of diminished segmental S/SR mirrored these findings. For the percentage of pathological segments with varying cut-off values, segmental SRe below 1.5 s- 1 displayed the most marked difference among the four groups (p < 0.001). Revascularized MI patients or those referred to CABG present with diminished segmental S/SR values. However, among patients with chronic chest pain, only segmental SRe discerns subtle disparities between the No-CAD and the PCI group. The diagnostic accuracy of SRe warrants further exploration in subsequent studies.

Evaluation of left ventricular systolic function in type 2 diabetes mellitus patients with and without peripheral vascular disease

BACKGROUND

Peripheral vascular disease (PVD) is a common complication of type 2 diabetes mellitus (T2DM). Patients with T2DM have twice the risk of PVD as nondiabetic patients.

AIM

To evaluate left ventricular (LV) systolic function by layer-specific global longitudinal strain (GLS) and peak strain dispersion (PSD) in T2DM patients with and without PVD.

METHODS

Sixty-five T2DM patients without PVD, 57 T2DM patients with PVD and 63 normal controls were enrolled in the study. Layer-specific GLS [GLS of the epimyocardium (GLSepi), GLS of the middle myocardium (GLSmid) and GLS of the endocardium (GLSendo)] and PSD were calculated. Receiver operating characteristic (ROC) analysis was performed to calculate the sensitivity and specificity of LV systolic dysfunction in T2DM patients with PVD. We calculated Pearson's correlation coefficients between biochemical data, echocardiographic characteristics, and layer-specific GLS and PSD.

RESULTS

There were significant differences in GLSepi, GLSmid and GLSendo between normal controls, T2DM patients without PVD and T2DM patients with PVD (P < 0.001). Trend tests revealed a ranking of normal controls > T2DM patients without PVD > T2DM patients with PVD in the absolute value of GLS (P < 0.001). PSD differed significantly between the three groups, and the trend ranking was as follows: normal controls < T2DM patients without PVD < T2DM patients with PVD (P < 0.001). ROC analysis revealed that the combination of layer-specific GLS and PSD had high diagnostic efficiency for detecting LV systolic dysfunction in T2DM patients with PVD. Low-density lipoprotein cholesterol was positively correlated with GLSepi, GLSmid and PSD (P < 0.05), while LV ejection fraction was negatively correlated with GLSepi, GLSmid and GLSendo in T2DM patients with PVD (P < 0.01).

CONCLUSION

PVD may aggravate the deterioration of LV systolic dysfunction in T2DM patients. Layer-specific GLS and PSD can be used to detect LV systolic dysfunction accurately and conveniently in T2DM patients with or without PVD.

The relationship between coronary artery calcium and layer-specific global longitudinal strain in patients with suspected coronary artery disease

PURPOSE

Layer-specific global longitudinal strain (GLS) may provide important insights in patients with suspected coronary artery disease (CAD). We aimed to investigate the association between layer-specific GLS and coronary artery calcium score (CACS) in patients suspected of CAD.

METHODS

We performed a retrospective study of patients suspected of CAD who underwent both an echocardiogram and cardiac computed tomography (median 42 days between). Layer-specific (endocardial-, whole-layer-, and epicardial-) GLS was measured using speckle tracking echocardiography. We assessed the continuous association between layer-specific GLS and CACS by negative binomial regression, and the association with high CACS (≥400) using logistic regression.

RESULTS

Of the 496 patients included (mean age 59 years, 56% male), 64 (13%) had a high CACS. Those with high CACS had reduced GLS in all layers compared to those with CACS < 400 (endocardial GLS: -20.5 vs. -22.7%, whole-layer GLS: -17.7 vs. -19.4%, epicardial GLS: -15.3 vs. -16.9%, p < .001 for all). Negative binomial regression revealed a significant continuous association showing increasing CACS with worsening GLS in all layers, which remained significant after multivariable adjustment including SCORE chart risk factors. All layers of GLS were associated with high CACS in univariable analyses, which was consistent after multivariable adjustment (endocardial GLS: OR = 1.11 (1.03-1.20); whole-layer GLS: OR = 1.14 (1.04-1.24); epicardial GLS: OR = 1.16 (1.05-1.29), per 1% absolute decrease).

CONCLUSION

In this study population with patients suspected of CAD and normal systolic function, impaired layer-specific GLS was continuously associated with increasing CACS, and decreasing GLS in all layers were associated with presence of high CACS.

Machine learning-enhanced echocardiography for screening coronary artery disease

BACKGROUND

Since myocardial work (MW) and left atrial strain are valuable for screening coronary artery disease (CAD), this study aimed to develop a novel CAD screening approach based on machine learning-enhanced echocardiography.

METHODS

This prospective study used data from patients undergoing coronary angiography, in which the novel echocardiography features were extracted by a machine learning algorithm. A total of 818 patients were enrolled and randomly divided into training (80%) and testing (20%) groups. An additional 115 patients were also enrolled in the validation group.

RESULTS

The superior diagnosis model of CAD was optimized using 59 echocardiographic features in a gradient-boosting classifier. This model showed that the value of the receiver operating characteristic area under the curve (AUC) was 0.852 in the test group and 0.834 in the validation group, with high sensitivity (0.952) and low specificity (0.691), suggesting that this model is very sensitive for detecting CAD, but its low specificity may increase the high false-positive rate. We also determined that the false-positive cases were more susceptible to suffering cardiac events than the true-negative cases.

CONCLUSIONS

Machine learning-enhanced echocardiography can improve CAD detection based on the MW and left atrial strain features. Our developed model is valuable for estimating the pre-test probability of CAD and screening CAD patients in clinical practice.

TRIAL REGISTRATION

Registered as NCT03905200 at ClinicalTrials.gov. Registered on 5 April 2019.

The clinical application of longitudinal layer specific strain as a diagnostic and prognostic instrument in ischemic heart diseases: A systematic review and meta-analysis

Background

2-dimensional Speckle-Tracking Echocardiography, to obtain longitudinal layer specific strain (LSS), has recently emerged as a novel and accurate non-invasive imaging technique for diagnosis as well as for prediction of adverse cardiac events. This systematic review and meta-analysis aimed to give an overview of the possible clinical implication and significance of longitudinal LSS.

Methods

We conducted a systematic review and meta-analysis with all the studies involving layer specific strain in patients with ischemic heart disease (IHD). Of 40 eligible studies, 9 met our inclusion criteria. Studies that were included either investigated the prognostic value (n = 3) or the diagnostic value (n = 6) of longitudinal LSS.

Results

The pooled meta-analysis showed that longitudinal LSS is a significant diagnostic marker for coronary artery disease (CAD) in patients with IHD. Endocardial LSS was found to be a good diagnostic marker for CAD in IHD patients (OR: 1.28, CI95% [1.11–1.48], p &lt; 0.001, per 1% decrease). Epicardial (OR: 1.34, CI95% [1.14–1.56], p &lt; 0.001, per 1% decrease), Mid-Myocardial (OR: 1.24, CI95% [1.12–1.38], p &lt; 0.001, per 1% decrease) and endocardial (OR: 1.21, CI95% [1.09–1.35], p &lt; 0.001, per 1% decrease) LSS all entailed diagnostic information regarding CAD, with epicardial LSS emerging as the superior diagnostic marker for CAD in patients with SAP. Endocardial LSS proved to be the better diagnostic marker of CAD in patients with non-ST elevation acute coronary syndrome (NSTE-ACS). LSS was shown to be a good prognostic maker of adverse cardiac events in IHD patients. Two studies found endocardial circumferential strain to be the good predictor of outcome in CAD patients and when added to baseline characteristics. Epicardial LSS emerged as best predictor in acute coronary syndrome (ACS) patients.

Conclusion

In patients with SAP, epicardial LSS was the stronger diagnostic marker while in NSTE-ACS patients, endocardial LSS was the stronger diagnostic marker. In addition, endocardial circumferential strain is the better predictor of adverse outcome in CAD patients whilst in ACS patients, epicardial LSS was found to be a better predictor of outcome.

Right ventricular strain predicts adverse outcomes in patients undergoing coronary artery bypass grafting

Patients undergoing coronary artery bypass grafting (CABG) face an elevated risk of heart failure (HF) and cardiovascular (CV) death. Detailed myocardial tissue analyses of the right ventricle are now possible and may hold prognostic value in these patients. Accordingly, we aimed to evaluate the usefulness of right ventricular (RV) layer-specific RV free wall strain (RVFWS) for predicting HF and/or CV death. Patients undergoing CABG at Gentofte Hospital from 2006 to 2011 with a preoperative echocardiogram underwent RVWFS analysis. RVFWS was obtained by speckle tracking. The outcome was defined as a composite of HF and/or CV death. Cox proportional hazards regression, Harrell's C-statistics, and competing risk regression were used to assess the prognostic value of RVFWS. Of 317 patients, 30 (9.5%) reached the endpoint at a median follow-up of 3.5 years. The mean age was 67 years, 83% were men, and the mean LVEF was 50%. In univariable analyses, endo-RVFWS (HR 1.08, P < 0.001), mid-RVFWS (HR 1.07, P = 0.002), and epi-RVFWS (HR 1.07, P = 0.004, per 1% absolute decrease) were associated with a higher risk of HF or/and CV death. Furthermore, all three layers remained independently associated with the outcome after multivariable adjustment for baseline clinical and echocardiographic measurements. Low endo-RVFWS was associated with a more than threefold increased risk of the outcome (HR = 3.04 (1.45-6.38) P = 0.003). The same was observed for mid-RVFWS (HR = 3.16 (1.45-6.91) P = 0.004), and epi-RVFWS (HR = 3.00 (1.46-6.17) P = 0.003). In patients undergoing CABG, RVFWS assessed by speckle-tracking is a predictor of adverse outcomes.

Regional Myocardial Work Measured by Echocardiography for the Detection of Myocardial Ischemic Segments: A Comparative Study With Invasive Fractional Flow Reserve

Purpose

This study is to assess the diagnostic value of noninvasive regional myocardial work (MW) by echocardiography for detecting the functional status of coronary stenosis using fractional flow reserve (FFR) as a standard criterion.

Methods

A total of 84 consecutive patients were included in this study, among which 92 vessels were identified with ≥50% stenosis confirmed by invasive coronary angiography. Patients were investigated by invasive FFR and transthoracic echocardiography. Regional MW indices including myocardial work index (MWI), myocardial constructive work (MCW), myocardial wasted work, and myocardial work efficiency were calculated.

Results

MWI and MCW were significantly impaired in the FFR ≤ 0.75 group compared with the FFR > 0.75 group (both p < 0.01). There were significant positive associations between MWI and MCW with FFR. In total group, MWI <1,623.7 mmHg% [sensitivity, 78.4%; specificity, 72.2%; area under the curve value, 0.768 (0.653-0.883)] and MCW <1,962.4 mmHg% [77.0%; 72.2%; 0.767 (0.661-0.872)], and in single-vessel subgroup, MWI <1,412.1 mmHg% [93.5%; 63.6%; 0.808 (0.652-0.965)] and MCW <1,943.3 mmHg% [(84.8%; 72.7%; 0.800 (0.657-0.943)] were optimal to detect left ventricular segments with an FFR ≤ 0.75. MWI and MCW significantly increased after percutaneous coronary intervention in 13 cases.

Conclusion

In patients with coronary artery disease, especially those with single-vessel stenosis, the regional MW measured by echocardiography exhibited a good diagnostic value in detecting significant myocardial ischemia compared to the standard FFR approach.

Evaluation of left ventricular function by treadmill exercise stress echocardiography combined with layer‐specific strain technique in essential hypertension patients

The purpose of this study was to evaluate the diagnostic utility of treadmill exercise stress echocardiography (TESE) combined with left ventricular (LV) layer‐specific strain (LSS) in subclinical myocardial and reserve function of hypertensive patients. A total of 55 hypertensive patients and 51 controls were evaluated during rest and exercise. Two‐dimensional speckle tracking (2DST) and LSS technique was used to measure longitudinal and circumferential strains at rest and peak exercise, strain difference characteristics were then evaluated. Compared to the control subjects, both longitudinal and circumferential LSS showed different degrees of reduction in hypertensive group, which was more pronounced at peak exercise. The global longitudinal endocardium strain (GLSendo) at rest was 24.4% ± 1.5% in the control group versus 20.4% ± 2.3% in the hypertensive group, while the difference was more obvious at peak state (control vs. hypertensive group, 30.8% ± 2.8% and 22.8% ± 2.9%, respectively). In particular, endocardial strain under exercise can be used as a sensitive indicator where the LV contractile reserve (CR) function of the three layers are all impaired. TESE combined with LSS might increase diagnostic accuracy of myocardial performance in hypertension patients.

Segmental Tissue Speckle Tracking Predicts the Stenosis Severity in Patients With Coronary Artery Disease

Objective

Two-dimensional speckle tracking echocardiography (2D-STE) has been used as a diagnostic tool for coronary artery disease (CAD). However, whether vessel supplied myocardial strain and strain rate (SR) predict the severity of coronary artery stenosis in patients with CAD is unknown. This study aimed to investigate correlation of cardiac mechanical parameters in tissue speckle tracking measurements with coronary artery stenosis diagnosed by cardiac catheterization in patients with clinically diagnosed CAD.

Methods and Results

Among 59 patients analyzed, 170 vessels were evaluated by coronary angiography and the corresponding echocardiography to quantify left ventricular myocardial strain and SR. The average longitudinal strain and SR of the segmental myocardium supplied by each coronary artery were calculated to achieve vessel myocardium strain (VMS) and strain rate (VMSR). The VMS and VMSR at each of four severity levels of stenosis showed significant differences among groups (p = 0.016, and p < 0.001, respectively). The strain and SR in vessels with very severe stenosis (≥75%, group IV; n = 29), 13.9 ± 4.3, and 0.9 ± 0.3, respectively, were significantly smaller than those of vessels with mild stenosis ≤ 25%, group I; n = 88, 16.9 ± 4.9, p = 0.023, and 1.2 ± 0.3, p = 0.001, respectively. The SR in vessels with moderate stenosis (26–49%, group II; n = 37), 1.0 ± 0.2, was significantly smaller than that in vessels with mild stenosis vessels (p = 0.021). The lower VMS and VMSR, the higher possibility of severe coronary stenosis is. The VMS and VMSR lower than 13.9 ± 4.3 and 0.9 ± 0.3, respectively predicted the severe coronary stenosis. The VMS and VMSR higher than 16.9 ± 4.9 and 1.2 ± 0.3, respectively predicted mild or no coronary artery stenosis.

Conclusions

The actual stenosis rate in catheterization demonstrates that this technique was able to assess coronary artery condition. Thus, the application of a non-invasive method of 2D-STE to evaluate and simplify diagnosis of CAD is feasible.

Layer-specific and whole wall global longitudinal strain predict major adverse cardiovascular events in patients with stable angina pectoris

Global longitudinal strain (GLS) has proven to be a powerful prognostic marker in various patient populations, but the prognostic value of layer-specific GLS has not yet been investigated in patients with suspected stable angina pectoris (SAP). We sought to investigate the prognostic value of layer-specific and whole wall GLS in patients with suspected SAP. From September 2008 to March 2011, 296 consecutive patients with clinically suspected SAP, normal ejection fraction, and no previous cardiac history were enrolled in a prospective cohort study. Patients underwent echocardiography including two-dimensional speckle tracking at rest, exercise stress test, and coronary angiography. The end-point was a composite of incident heart failure, acute myocardial infarction, and cardiovascular death (MACE). Out of the 285 included patients (mean age 61 years, 50% male), 24 (8%) developed MACE during a median follow-up of 3.5 years. Both endocardial [hazard ratio (HR) 1.21, 95% CI 1.08-1.35, p = 0.001], epicardial (HR 1.29, 95% CI 1.12-1.50, p = 0.001) and whole wall GLS (HR 1.25, 1.10-1.42, p = 0.001) were significantly associated with an increased risk of developing MACE during follow-up in univariable Cox regression analysis. In multivariable analysis, only epicardial (HR 1.23, 95% CI 1.00-1.51, p = 0.046) and whole wall GLS (HR 1.20, 95% CI 1.00-1.43, p = 0.049) remained significantly associated with an increased risk of MACE independent of various baseline clinical variables, left ventricular ejection fraction (LVEF), E/e' and Duke Score. Layer-specific and whole wall GLS were significant predictors of MACE in this cohort of patients with suspected SAP independent of various baseline clinical variables, LVEF, E/e' and Duke Score.

RETRACTED: Diagnosis of Early Left Ventricular Systolic Dysfunction by Layer-Specific Strain Echocardiography in Diabetic Rabbits

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor. The authors have copied figures and text verbatim from another manuscript published by the first author and others in Med Ultrason, 18 (2016) 339–344; doi:10.11152/mu.2013.2066.183.qia. We apologize to readers of the journal for this incident.

Change in global longitudinal strain following acute coronary syndrome and subsequent risk of heart failure

Global Longitudinal Strain (GLS) is a well-established predictor of heart failure (HF) following acute coronary syndrome (ACS). We aim to investigate the prognostic value of GLS obtained at a follow-up consultation, as well as the change in GLS for long-term risk of incident HF. A total of 235 ACS patients had an echocardiogram performed immediately after percutaneous coronary intervention (PCI) and a follow-up echocardiogram (FUE) median 215 (IQR: 71; 878) days after the first echocardiogram. Endpoint was incident HF. Follow-up time after FUE was median 4.8 (IQR: 3.7; 5.6) years. Patients diagnosed with HF before FUE were excluded. Mean age was 63 ± 11 years and 77% were male. Baseline GLS was on average 12.7 ± 3.9%, FUE GLS was on average 13.5 ± 3.9% and mean improvement in GLS was 0.73 ± 3.68% between the 2 echocardiograms. A total of 57 (24%) patients suffered incident HF following the FUE. FUE GLS provided significantly higher prognostic information for risk of incident HF than ∆GLS when assessed by the C-statistics (C-statistics: 0.71 vs. 0.61, P = 0.021). Furthermore, after multivariable adjustments only FUE GLS [HR = 1.15, 95% CI (1.02; 1.29), P = 0.018, per 1% decrease] remained an independent predictor of incident HF. In patients with ACS, who do not develop HF before FUE, FUE GLS was an independent predictor of long-term risk of incident HF while ∆GLS was not.

Rapidly and Accurately Detecting Significant Coronary Artery Stenosis in Patients with Suspected Stable Coronary Artery Disease and Normal Segmental Wall Motion by Speckle Tracking Automated Functional Imaging

This study was performed to explore the value of a machine with built-in speckle tracking automated functional imaging (AFI) in predicting the severity of coronary artery lesions in patients with suspected stable coronary artery disease (SCAD) with normal wall motion. One hundred forty-three consecutive patients with clinically suspected SCAD with normal wall motion were included. Multiple parameters, including global longitudinal peak strain, post-systolic index (PSI) and peak strain dispersion, were automatically analyzed with AFI. Territorial longitudinal strain (TLS) and territorial PSI (TPSI) were also calculated. Receiver operating characteristic curve analyses revealed that global longitudinal peak strain and PSI were superior to other parameters in detecting left main or three-vessel SCAD. A combination of TLS and TPSI could improve diagnostic performance in identifying significant stenotic left anterior descending and right coronary arteries. In conclusion, 2-dimensional speckle tracking AFI can rapidly provide multiple parameters for detecting significant coronary artery stenosis with high accuracy in patients suspected of having SCAD with normal wall motion.

Age- and sex-based normal values of layer-specific longitudinal and circumferential strain by speckle tracking echocardiography: the Copenhagen City Heart Study

AIMS

Technical advancements in 2D-speckle tracking echocardiography (2DSTE) have allowed for quantification of layer-specific global longitudinal strain (GLS) and circumferential strain (GCS) of the left ventricle (LV). The aim of this study was to establish age- and sex-based reference ranges of peak systolic layer-specific GLS and GCS and to assess normal values of regional strain.

METHODS AND RESULTS

We performed 2DSTE analysis of 1997 members of the general population from the fifth round of the Copenhagen City Heart Study, who were free of cardiovascular disease and risk factors. The mean age was 46 ± 16 years (range 21-97) and 62% were female. Mean values for peak systolic whole wall GLS (GLSWW.Sys), endomycardial (GLSEndo.Sys), and epimyocardial (GLSEpi.Sys) were 19.9 ± 2.1% (prediction interval [PI]: 15.8-24.0%), 23.5 ± 2.5% (PI: 18.6-28.4%), and 17.3 ± 1.9% (PI: 13.6-21.1%), respectively. Mean peak systolic whole wall GCS (GCSWW.Sys), was 21.6 ± 3.7% (PI: 14.3-28.9%), endomyocardial (GCSEndo.Sys) was 31.9 ± 4.7% (PI: 22.7-41.1%), and epimyocardial (GCSEpi.Sys) was 14.3 ± 3.8% (PI: 6.8-21.8%). A significant discrepancy in normal strain values between males and females was observed. Men had lower mean values and lower reference limits for all strain parameters. Furthermore, GLS and GCS changed differently with age in males and females. Finally, regional LS decreased from the apical to the basal LV region in both sexes, and regional CS varied significantly by LV segment.

CONCLUSION

In this study, we reported age- and sex-based reference ranges of layer-specific GLS and GCS. These reference ranges varied significantly with sex and age.

The evaluation of right ventricular function in patients with diabetes mellitus and significant stenosis at the proximal portion of the right coronary artery

PURPOSE

Previous studies have indicated that right ventricular (RV) function is damaged in diabetes mellitus (DM); however, it is not clear whether in the presence of chronic ischemia, RV function is different between patients with and without DM (DM + and DM - , respectively).

METHODS

This cross-sectional study enrolled 90 consecutive candidates for coronary artery bypass graft surgery and allocated them to 3 groups: 24 DM - patients with the absence of stenosis of more than 50% in the proximal and mid parts of the right coronary artery (the DM - RCA - group [control]), 33 DM - patients with the presence of significant stenosis (> 70%) in the proximal part of RCA (the DM - RCA + group), and 33 DM + patients with RCA + (the DM + RCA + group). RV function was evaluated based on longitudinal deformation markers, measured via the 2D speckle-tracking echocardiographic examination of right ventricular free wall (RVFW).

RESULTS

The systolic strain value, systolic strain rate, and late diastolic strain rate of RVFW were not statistically significantly different between the three groups. Our adjusted post hoc analysis showed that the early diastolic strain rate of RVFW in the DM + RCA + group was lower than that in the DM - RCA + and DM - RCA - groups (1.5 s^-1 ± 0.4 vs 1.7 s^-1 ± 0.5 vs 1.7 s^-1 ± 0.4).

CONCLUSIONS

Diastolic function in the presence of DM was impaired irrespective of RCA - or RCA + . Additionally, RCA + had no effect on systolic and diastolic RV functions at rest in our DM - patients.

Two-Dimensional Speckle Tracking Echocardiography Identifies Coronary Artery Disease in 690 Patients: A Retrospective Study from a Single Center

BACKGROUND Two-dimensional speckle tracking echocardiography (2D-STE) is a novel and non-invasive technique for the diagnosis of coronary artery disease (CAD). This retrospective study from a single center aimed to identify myocardial ischemia using 2D-STE in CAD patients identified by angiography. MATERIAL AND METHODS From March 1 to November 30, 2019, 690 patients in Beijing Hospital were enrolled. After angiography, 346 patients were diagnosed with CAD. Reduction in vessel diameter of ≥50% by stenosis in at least 1 major coronary artery or its main branch was considered CAD. Analysis of 2D-STE was performed using EchoPAC version 201. RESULTS The global strain was significantly impaired in CAD patients (P<0.01). Global longitudinal peak strain (GLPS) was analyzed in layers. For GLPS of the epicardium, the odds ratio (OR) was 1.297 (1.217-1.382; P=0.002), the area under the curve (AUC) was 0.727, and the cut-off value was -16.95; sensitivity and specificity were 73.7% and 63.0%, respectively. For GLPS of the middle layer, the OR was 1.260 (1.192-1.333; P<0.001), the AUC was 0.732, and the cut-off value was -20.95; sensitivity and specificity were 82.4% and 56.2%, respectively. For GLPS of the endocardium, the OR was 1.193 (1.137-1.251; P<0.001), the AUC was 0.708, and the cut-off value was -22.95; sensitivity and specificity were 82.9% and 52.9%, respectively. CONCLUSIONS The findings from this study support the clinical application of 2D-STE in patient populations with suspected myocardial ischemia due to CAD. Therefore, 2D-STE combined with ECG monitoring may have a future role for early screening of CAD patients.

Speckle Tracking Echocardiography: Early Predictor of Diagnosis and Prognosis in Coronary Artery Disease

Echocardiography represents a first level technique for the evaluation of coronary artery disease (CAD) which supports clinicians in the diagnostic and prognostic workup of these syndromes. However, visual estimation of wall motion abnormalities sometimes fails in detecting less clear or transient myocardial ischemia and in providing accurate differential diagnosis. Speckle tracking echocardiography (STE) is a widely available noninvasive tool that could easily and quickly provide additive information over basic echocardiography, since it is able to identify subtle myocardial damage and to localize ischemic territories in accordance to the coronary lesions, obtaining a clear visualization with a "polar map" useful for differential diagnosis and management. Therefore, it has increasingly been applied in acute and chronic coronary syndromes using rest and stress echocardiography, showing good results in terms of prediction of CAD, clinical outcome, left ventricular remodeling, presence, and quantification of new/residual ischemia. The aim of this review is to illustrate the current available evidence on STE usefulness for the assessment and follow-up of CAD, discussing the main findings on bidimensional and tridimensional strain parameters and their potential application in clinical practice.

Early diastolic strain rate by two-dimensional speckle tracking echocardiography is a predictor of coronary artery disease and cardiovascular events in stable angina pectoris

This study aimed to clarify the diagnostic and prognostic potential of strain rate in patients with suspected stable angina pectoris (SAP). Strain rate by 2-dimensional speckle tracking echocardiography (2DSTE) has been suggested to be able to diagnose coronary artery disease (CAD) and predict cardiovascular events in various patient groups. Prospectively enrolled patients (n = 296) with suspected SAP, no previous cardiac disease, and normal left ventricular ejection fraction were examined by 2DSTE, exercise ECG, and coronary angiography. Obstructive CAD was defined as stenosis ≥ 70% in ≥ 1 coronary artery on coronary angiography (n = 107). Major adverse cardiac events (MACE) included myocardial infarction, heart failure, atrial fibrillation, and stroke. In multivariable analysis adjusted for baseline data, conventional echocardiography, and Duke score, early diastolic strain rate (SRe) was independently associated with significant CAD with a 1.35 increased risk of having CAD per 0.1 decrease in SRe (OR = 1.35, 95% CI 1.03-1.76, P = 0.027). Peak velocity of early diastolic filling (E)/SRe was not associated with significant CAD (OR = 1.14, 95% CI 0.81-1.62, P  = 0.445). MACE occurred in 34 patients (12%) during follow-up (median 3.5 years) and both SRe (HR 1.26, 95% CI (1.07-1.49), P = 0.006) and E/SRe (HR 1.24, 95% CI (1.04-1.47), P = 0.017) were independent predictors after multivariable adjustment. In patients with suspected SAP, SRe by 2DSTE was independently associated with presence of CAD. In addition, SRe and E/SRe provided independent and incremental prognostic value for predicting future MACE.