The Advantage of Global Strain Compared to Left Ventricular Ejection Fraction to Predict Outcome after Acute Myocardial Infarction

Cirrhotic cardiomyopathy: a subject that's always topical

Cirrhosis is the final stage in the development of hepatic fibrosis in chronic liver disease. It is associated with major hemodynamic disturbances defining the hyperdynamic circulation and may be complicated by specific cardiac involvement or cirrhotic cardiomyopathy which is a silent clinical condition that typically remains asymptomatic until the late stages of liver disease. Recently, new criteria defining CC, based on modern concepts and knowledge of heart failure, have been proposed. Despite knowledge of the main mechanisms behind this entity, there is no specific treatment available for cirrhotic cardiomyopathy. The management approach for symptomatic cardiomyopathy in cirrhotic patients is similar to that for left ventricular failure in non-cirrhotic individuals.

Strain Imaging and Ventricular Arrhythmia

Ventricular arrhythmia is one of the main causes of sudden cardiac death. Hence, identifying patients at risk of ventricular arrhythmias and sudden cardiac death is important but can be challenging. The indication for an implantable cardioverter defibrillator as a primary preventive strategy relies on the left ventricular ejection fraction as a measure of systolic function. However, ejection fraction is flawed by technical constraints and is an indirect measure of systolic function. There has, therefore, been an incentive to identify other markers to optimize the risk prediction of malignant arrhythmias to select proper candidates who could benefit from an implantable cardioverter defibrillator. Speckle-tracking echocardiography allows for a detailed assessment of cardiac mechanics, and strain imaging has repeatedly been shown to be a sensitive technique to identify systolic dysfunction unrecognized by ejection fraction. Several strain measures, including global longitudinal strain, regional strain, and mechanical dispersion, have consequently been proposed as potential markers of ventricular arrhythmias. In this review, we will provide an overview of the potential use of different strain measures in the context of ventricular arrhythmias.

Considering Both GLS and MD for a Prognostic Value in Non-ST-Segment Elevated Acute Coronary Artery Syndrome

Global longitudinal strain (GLS) and mechanical dispersion (MD), as determined by 2D speckle tracking echocardiography, have been demonstrated to be reliable indicators of prognosis in a variety of cardiovascular illnesses. There are not many papers that discuss the prognostic significance of GLS and MD in a population with non-ST-segment elevated acute coronary syndrome (NSTE-ACS). Our study objective was to examine the predictive utility of the novel GLS/MD two-dimensional strain index in NSTE-ACS patients. Before discharge and four to six weeks later, echocardiography was performed on 310 consecutive hospitalized patients with NSTE-ACS and effective percutaneous coronary intervention (PCI). Cardiac mortality, malignant ventricular arrhythmia, or readmission owing to heart failure or reinfarction were the major end points. A total of 109 patients (35.16%) experienced cardiac incidents during the follow-up period (34.7 ± 8 months). The GLS/MD index at discharge was determined to be the greatest independent predictor of composite result by receiver operating characteristic analysis. The ideal cut-off value was -0.229. GLS/MD was determined to be the top independent predictor of cardiac events by multivariate Cox regression analysis. Patients with an initial GLS/MD > -0.229 that deteriorated after four to six weeks had the worst prognosis for a composite outcome, readmission, and cardiac death according to a Kaplan-Meier analysis (all p < 0.001). In conclusion, the GLS/MD ratio is a strong indicator of clinical fate in NSTE-ACS patients, especially if it is accompanied by deterioration.

Highlighting the role of global longitudinal strain assessment in valvular heart disease

Background

Echocardiography has been the choice for imaging modality for valvular heart disease. It is less invasive, widely available, and allows valvular structure visualization. Echocardiographic assessment often also determines the management. Left ventricular ejection fraction is the most commonly used indicator during echocardiography assessment. It shows signs of left ventricular dysfunction in patients with valve disease. However, most of the time, the ongoing process of cardiac damage may already occur even with preserved cardiac function; further deteriorated ejection fraction will show irreversible cardiac damage. There is a need for a more advanced diagnostic tool to detect early cardiac dysfunction, to prevent further damage.

Main body

Advanced echocardiography imaging using strain imaging allows a physician to evaluate cardiac function more precisely. A more sensitive parameter than left ventricular ejection fraction, global longitudinal strain, can evaluate subclinical myocardial dysfunction before the symptoms occur by evaluating complex cardiac mechanisms. Global longitudinal strain evaluation provides the chance for physicians to determine the intervention needed to prevent further deterioration and permanent cardiac dysfunction. Global longitudinal strain is proven to be beneficial in many types of valvular heart diseases, especially in mitral and aortic valve diseases. It has an excellent diagnostic and prognostic value for patients with valve disease. This review aims to present the superiority of global longitudinal strain compared to left ventricular ejection fraction in assessing cardiac function in patients with valvular heart disease. Clinical usage of global longitudinal strain in several valvular heart diseases is also presented in this review.

Conclusions

The superiority of global longitudinal strain to left ventricular ejection fraction relies on the mechanism where other strains would compensate for the deterioration of longitudinal strain, which is more vulnerable to damage, so the cardiac function is preserved. Therefore, examination of longitudinal strain would give the physician early signs of cardiac function impairment, and prompt management can be conducted.

Increased deformation of the left ventricle during exercise test measured by global longitudinal strain can rule out significant coronary artery disease in patients with suspected unstable angina pectoris

BACKGROUND

Noninvasive identification of significant coronary artery disease (CAD) in patients with unstable angina pectoris (UAP) is challenging. Exercise stress testing has been used for years in patients with suspected CAD but has low diagnostic accuracy. The use of Global longitudinal strain (GLS) by speckle tracking echocardiography is a highly sensitive and reproducible parameter for detection of myocardial ischemia. Our aim was to study if identification of normal or ischemic myocardium by measurement of GLS immediately after an ordinary bicycle exercise stress testing in patients with suspected UAP could identify or rule out significant CAD.

METHODS

Seventy-eight patients referred for coronary angiography from outpatient clinics and the emergency department with chest pain, inconclusive ECG and normal values of Troponin-T was included. All patients underwent echocardiographic examination at rest and immediately after maximum stress by exercise on a stationary bicycle. Significant CAD was defined by diameter stenosis > 90% by coronary angiography. In patients with coronary stenosis between 50-90%, fractional flow reserve (FFR) was measured and defined abnormal < .80. Analysis of echocardiographic data were performed blinded for angiographic data. Patients were discharged diagnosed with CAD (n = 34) or non-coronary chest pain (NCCP, n = 44).

RESULTS

In patients with NCCP, GLS at rest was -21.1 ± 1.7% and -25.5 ± 2.6% at maximum stress (P < .01). In patients with CAD, GLS at rest was -16.8 ± 4.0% and remained unchanged at maximum stress (-16.6 ± 4.6%, P = .69). In patients with NCCP, LVEF was 56.1% ± 6.0 and increased to 61.8% 5.2, P < .01. In CAD patients, LVEF at rest was 54.7% ± 8.6 and increased to 58.2% ± 9.5 during stress, P = .16. In NCCP patients, Wall Motion Score index decreased .02 ± .07, P = .03 during stress and was without significant changes in patients with CAD. Area under the curve (AUC) for distinguishing CAD for was .97 (.95-1.00), .63 (.49-.76), and .71 (.59-.83) for GLS, LVEF, and WMSi, respectively.

CONCLUSION

In patients with suspected UAP, increased deformation of the left ventricle measured by GLS immediately after exercise stress testing identified normal myocardium without CAD. Reduced LV contractile function by GLS without increase after exercise identified significant CAD.

Prognostic impact of non-improvement of global longitudinal strain in patients with revascularized acute myocardial infarction

Global longitudinal strain (GLS) is a more sensitive prognostic factor than left ventricular ejection fraction (LVEF) in various cardiac diseases. Little is known about the clinical impact of GLS changes after acute myocardial infarction (AMI). The present study aimed to explore if non-improvement of GLS after 3 months was associated with higher risk of subsequent composite cardiovascular events (CCVE). Patients with AMI were consecutively included at a secondary care center in Norway between April 2016 and July 2018 within 4 days following percutaneous coronary intervention. Echocardiography was performed at baseline and after 3 months. Patients were categorized with non-improvement (0 to - 100%) or improvement (0 to 100%) in GLS relative to the baseline value. Among 214 patients with mean age 65 (± 10) years and mean LVEF 50% (± 8) at baseline, 50 (23%) had non-improvement (GLS: - 16.0% (± 3.7) to - 14.2% (± 3.6)) and 164 (77%) had improvement (GLS: - 14.0% (± 3.0) to - 16.9% (± 3.0%)). During a mean follow-up of 3.3 years (95% CI 3.2 to 3.4) 77 CCVE occurred in 52 patients. In adjusted Cox regression analyses, baseline GLS was associated with all recurrent CCVE (HR 1.1, 95% CI 1.0 to 1.2, p < 0.001) whereas non-improvement versus improvement over 3 months follow-up was not. Baseline GLS was significantly associated with the number of CCVE in revascularized AMI patients whereas non-improvement of GLS after 3 months was not. Further large-scale studies are needed before repeated GLS measurements may be recommended in clinical practice.Trial registration: Current Research information system in Norway (CRISTIN). Id: 506563.

Structural and Physiological Imaging to Predict the Risk of Lethal Ventricular Arrhythmias and Sudden Death

Identifying patients at risk of sudden cardiac death remains a major challenge in cardiovascular medicine. Advances in cardiovascular imaging have identified several anatomic and functional variables that can be quantified as continuous variables to predict the risk of developing lethal ventricular tachyarrhythmias in patients with depressed left ventricular (LV) systolic function. Some, such as LV mass, volume, and the dyssynchrony of contraction, can be derived from currently available echocardiographic and nuclear imaging modalities. Others require advanced cardiac imaging modalities with quantification of myocardial scar with gadolinium-enhanced cardiac magnetic resonance and myocardial sympathetic denervation using norepinephrine analogs and positron emission tomography or single-photon emission computed tomography offering the most promise. There is an immediate need to develop a sequential cost-effective approach that capitalizes on readily available clinical information complemented with advanced imaging modalities in selected patients to improve risk stratification for arrhythmic death beyond LV ejection fraction.

Redefining Cirrhotic Cardiomyopathy for the Modern Era

Cirrhotic cardiomyopathy (CCM) is cardiac dysfunction in patients with end-stage liver disease in the absence of prior heart disease. First defined in 2005 during the World Congress of Gastroenterology, CCM criteria consisted of echocardiographic parameters to identify subclinical cardiac dysfunction in the absence of overt structural abnormalities. Significant advancements in cardiovascular imaging over the past 14 years, including the integration of myocardial deformation imaging into routine clinical practice to identify subclinical cardiovascular dysfunction, have rendered the 2005 CCM criteria obsolete. Therefore, new criteria based on contemporary cardiovascular imaging parameters are needed. In this guidance document, assembled by a group of multidisciplinary experts in the field, new core criteria based on contemporary cardiovascular imaging parameters are proposed for the assessment of CCM. This document provides a critical assessment of the diagnosis of CCM and ongoing assessment aimed at improving clinical outcomes, particularly surrounding liver transplantation. Key points and practice-based recommendations for the diagnosis of CCM are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.

Global longitudinal strain is a more reproducible measure of left ventricular function than ejection fraction regardless of echocardiographic training

Background

Left ventricular ejection fraction (LVEF) is an established method for evaluation of left ventricular (LV) systolic function. Global longitudinal strain (GLS) by speckle tracking echocardiography seems to be an important additive method for evaluation of LV function with improved reproducibility compared with LVEF. Our aim was to compare reproducibility of GLS and LVEF between an expert and trainee both as echocardiographic examiner and analyst.

Methods

Forty-seven patients with recent Acute Coronary Syndrome (ACS) underwent echocardiographic examination by both an expert echocardiographer and a trainee. Both echocardiographers, blinded for clinical data and each other’s findings, performed image analysis for evaluation of intra- and inter- observer variability. GLS was measured using speckle tracking echocardiography. LVEF was calculated by Simpson’s biplane method.

Results

The trainee measured a GLS of − 19.4% (±3.5%) and expert − 18.7% (±3.2%) with an Intra class correlation coefficient (ICC) of 0.89 (0.74–0.95). LVEF by trainee was 50.3% (±8.2%) and by expert 53.6% (±8.6%), ICC coefficient was 0.63 (0.32–0.80). For GLS the systematic difference was 0.21% (− 4.58–2.64) vs. 4.08% (− 20.78–12.62) for LVEF.

Conclusion

GLS is a more reproducible method for evaluation of LV function than LVEF regardless of echocardiographic training.

Two-dimensional-strain echocardiography in intensive care unit patients: A prospective, observational study

PURPOSE

Two-dimensional-strain echocardiography (2D-strain) is a promising technique for the early detection of myocardial dysfunction. Our study was aimed to assess its feasibility in the intensive care unit (ICU). Our secondary goal was to determine if 2D-strain could predict the patient's outcome.

METHODS

Conventional echocardiography and 2D-strain were performed on 64 consecutive patients admitted to our ICU. Using 2D-strain, the longitudinal deformation of the left ventricle was assessed. Feasibility of 2D-strain, diagnosis performance, and 28-day mortality prediction were determined.

RESULTS

2D-strain measurements could be performed in 77% of our patients. All 2D-strain variables related to ventricular performance were significantly impaired in the patients who died compared with those who survived. Strain global medium was the only independent echocardiographic variable predictor of 28-day mortality rate (odds ratio 0.60; 95% confidence interval 0.43-0.80, p = 0.002).

CONCLUSIONS

2D-strain measurement is feasible in ICU patients, enabling identifying early left ventricle dysfunction. Strain global medium is an independent predictor of 28-day mortality. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 44:368-374, 2016.

Left atrial remodeling in patients undergoing percutaneous mitral valve repair with the MitraClip system: an advanced echocardiography study

BACKGROUND

The goal of this study was to determine changes in left atrial (LA) function with two-dimensional speckle tracking echocardiography (2DSTE) and real-time full-volume three-dimensional echocardiography (RT3DE) after percutaneous mitral valve repair with the MitraClip system. Furthermore, we investigated whether baseline and/or changes in LA function after MitraClip repair had any impact on prognosis.

METHODS

A total of 25 consecutive patients (age: 57±12 years, 76% male) with moderate-to-severe or severe mitral regurgitation (MR) were included. Patients underwent 2DSTE and RT3DE before the clip implantation and after the 12-month follow-up. Prognostic data were also recorded via the use of telephone calls and follow-up visits for 12 months after the procedure.

RESULTS

Compared with the baseline, the LA reservoir strain (LA-Res) (7.66±4.3% vs 11.15±7.5%, P<.001) and LA contraction strain (LA-Pump) (4.64±4.3% vs 7.63±5.8%, P=.001) improved significantly after MitraClip repair; significant improvements were also seen in three-dimensional (3D) minimum LA volume index (LAV min) and maximum LA volume index (LAV max). On the other hand, conventional LA indices did not change. In total, eleven major adverse cardiac events (MACE) were observed at the 1-year follow-up. In univariate analyses, the preprocedural echocardiographic parameters that were associated with the MACE within 1 year after MitraClip repair were 3D-LAV min and LA-Res. Furthermore, these indices significantly correlated with improved functional parameters and MR reduction.

CONCLUSION

In conclusion, a successful MitraClip procedure can reverse the process of LA remodeling within 12 months, and this can be detected by 2DSTE and RT3DE. Also, patients with preprocedural lower LA-Res and higher 3D-LAV min had the worst prognoses at the 1-year follow-up.

The prognostic value of mechanical left ventricular dyssynchrony in patients with acute coronary syndrome

Background

Echocardiography is a well-established tool for risk stratification in patients with acute coronary syndrome (ACS). ACS has significant impact on LV dyssynchrony, and detrimental effects on systolic function and long term outcome. The aims of this study were to determine whether LV dyssynchrony carries any predictive information in an unselected ACS population and to evaluate if it has any incremental value to the information given from conventional echocardiographic measurements.

Methods

The study included 227 consecutive ACS patients. Primary endpoint was the composite of death, new MI, or rehospitalisation due to heart failure. Dyssynchrony was measured as intersegmental variation of time to peak strain, the post systolic index (PSI) and myocardial performance index (MPI) with the standard deviation and difference between lowest and highest value (delta) expressing the amount of dyssynchrony. Septal-lateral delay was also tested. All dyssynchrony parameters were compared with Ejection fraction (EF).

Results

The median follow up time was 53 months. 85 patients reached the combined endpoint. Patients with and without a subsequent combined endpoint differed significantly regarding calculated SD: s and delta-value for PSI, time to peak 2D-strain and MPI but not regarding septal-lateral delay. In ROC-analysis none of the dyssynchrony parameters had larger AUC than EF. When adjusting for traditional risk factors none of the dyssynchrony parameters remained associated with outcome, whereas EF still did.

Conclusion

LV dyssynchrony seem to have significant prognostic information in patient with acute coronary syndrome but in comparison to conventional parameters such as EF there is no incremental value of this information.

Feasibility and reproducibility of systolic right ventricular strain measurement by speckle-tracking echocardiography in premature infants

BACKGROUND

Right ventricular (RV) systolic function is an important prognostic determinant of cardiopulmonary pathologies in premature infants. Measurements of dominant RV longitudinal deformation are likely to provide a sensitive measure of RV function. An approach for image acquisition and postacquisition processing is needed for reliable and reproducible measurements of myocardial deformation by two-dimensional (2D) speckle-tracking echocardiography. The aims of this study were to determine the feasibility and reproducibility of 2D speckle-tracking echocardiographic measurement of RV peak global longitudinal strain (pGLS) and peak global longitudinal strain rate in premature infants and to establish methods for acquiring and analyzing strain.

METHODS

The study was designed in two phases: (1) a training phase to develop methods of image acquisition and postprocessing in a cohort of 30 premature infants (born at 28 ± 1 weeks) and (2) a study phase to prospectively test in a separate cohort of 50 premature infants (born at 27 ± 1 weeks) if the methods improved the feasibility and reproducibility of RV pGLS and peak global longitudinal strain rate measurements to a clinically significant level, assessed using Bland-Altman analysis (bias, limits of agreement, coefficient of variation, and intraclass correlation coefficient).

RESULTS

Strain imaging was feasible from 84% of the acquisitions using the methods developed for optimal speckle brightness and frame rate for RV-focused image acquisition. There was high intraobserver (bias, 3%; 95% limits of agreement, -1.6 to +1.6; coefficient of variation, 2.7%; intraclass correlation coefficient, 0.97; P = .02) and interobserver (bias, 7%; 95% limits of agreement, -4.8 to +4.73; coefficient of variation, 3.9%; intraclass correlation coefficient, 0.93; P < .05) reproducibility, with excellent linear correlation between the two pGLS measurements (r = 0.97 [P < .01] and r = 0.93 [P < .05], respectively).

CONCLUSIONS

This study demonstrates high clinical feasibility and reproducibility of RV pGLS and RV peak global longitudinal strain rate measurements by 2D speckle-tracking echocardiography in premature infants and offers methods for image acquisition and data analysis for systolic strain imaging that can provide a reliable assessment of global RV function.

Peak systolic velocity using color-coded tissue Doppler imaging, a strong and independent predictor of outcome in acute coronary syndrome patients

Background

Traditional echocardiographic methods like left ventricular ejection fraction(EF) and wall motion scoring (WMS) and new methods like speckle tracking (ST) based 2D strain carry important prognostic information in acute coronary syndrome (ACS) patients. Parameters from tissue Doppler imaging (TDI), with its high time resolution, may further increase the prognostic value. Peak systolic velocity (PSV) of the basal segments of the left ventricle from TDI is a robust and user independent parameter. The aim was to investigate the prognostic value of PSV compared to EF, WMS, 2D strain and E/e'.

Methods

Echocardiographic images were collected and post processed in 227 ACS patients. Additional clinical data was prospectively gathered and patients were followed for 3-5 years regarding the combined endpoint of death or re-admission due to ACS or heart failure.

Results

The combined endpoint occurred in 85 (37%) patients. Those with an event had lower median PSV than those without (4,4 cm/s) vs. (5,3 cm/s), (p<0.001). In a ROC analysis, the AUC was larger for PSV (0.75) than for EF (0.68), WMS (0.63), 2D strain (0.67) and E/e'(0.70). The combined endpoint increased with decreasing PSV. When adjusting for differences in baseline characteristics in a COX-regression model, PSV remained independently associated with outcome where the others did not. PSV was also less sensitive to image quality with fewer values missing or unacceptable for analysis.

Conclusion

Peak systolic velocity (PSV) is a robust measurement that seems to have a strong and independent association with outcome compared to traditional echocardiographic measurements in ACS patients.

Correlation between left ventricular global and regional longitudinal systolic strain and impaired microcirculation in patients with acute myocardial infarction

OBJECTIVES

We investigated the correlation between left ventricular global and regional longitudinal systolic strain (GLS and LRS) and coronary flow reserve (CFR) assessed by transthoracic echocardiography (TTE) in patients with a recent acute myocardial infarction (AMI). Furthermore, we investigated if LRS and GLS imaging is superior to conventional measures of left ventricle (LV) function.

METHODS

In a consecutive population of first time AMI patients, who underwent successful revascularization, we performed comprehensive TTE. GLS and LRS were obtained from the three standard apical views. Assessment of CFR by TTE was performed in a modified apical view using color Doppler guidance.

RESULTS

The study population consisted of 183 patients (51 females) with a median age of 63 [54;70] years. Eighty-nine (49%) patients had a non-ST elevation myocardial infarction and 94 (51%) patients had a ST elevation myocardial infarction. The GLS was -15.2 [-19.3;-10.1]% in the total population of 183 patients. Total wall motion score index (WMSI) in the population was 1.19 [1;1.5]. Eighty-five patients suffered from culprit lesion in left anterior descending artery (LAD). The CFR in these patients was 1.86 [1.36;2.35] and the GLS was -14.3 [-18.9; -9.8]%. A significant difference was observed in the LRS in LAD territory in culprit LAD infarction patients with a CFR ≤ 2 (-9.6 [-13.77;-6.44]) compared with the LRS in LAD territory in culprit LAD infarction patients with a CFR > 2 (-19.33 [-21.1;-16.5]), P < 0.0001. We found no significant difference between WMSI in LAD territory in culprit LAD infarction patients with a CFR ≤ 2 (1.56 [1.06;2.23]) compared with WMSI in LAD territory in culprit LAD infarction patients with a CFR > 2 (1.37 [1.03;2.11]); P = 0.18. The same pattern was observed in both circumflex coronary artery (CX) and right coronary artery (RCA) territories. In the total population, we found a strong correlation between CFR and GLS (r = -0.85, P < 0.0001). This was also seen in the multivariate regression model adjusting for possible confounders including WMSI (P < 0.001).

CONCLUSION

In this study, we have shown a close association between myocardial deformation in patients with a recent AMI and the degree of diminished microcirculation. We found that both GLS and LRS correlated with CFR. We conclude that GLS and LRS are significantly better tools to assess impaired CFR and LV function after a recent AMI, than conventional echocardiographic measurements.

Systolic heart function remains depressed for at least 30 days after on-pump cardiac surgery

OBJECTIVES

The myocardial recovery time following on-pump cardiac surgery remains uncertain. Global peak longitudinal strain is a sensitive measure of endocardial function which is most susceptible to ischaemia. We aimed to evaluate changes in global peak longitudinal strain up to 6 months after surgery and to compare initial changes with alterations in troponin T. Secondarily, we aimed to describe perioperative changes in strain of the inter-ventricular septum when compared with reference segments.

METHODS

Patients scheduled for coronary bypass, aortic valve replacement or combination procedures were enrolled. Echocardiography was performed on the day before surgery, the day after surgery, 4 days after surgery, 30 days after surgery and 6 months after surgery. Troponin T was measured 3, 16 and 24 h following procedure.

RESULTS

Forty patients were enrolled and one was later excluded. Global peak longitudinal strain decreased from -14.5 ± 3.33% preoperatively to -9.98 ± 3.09% and -10.57 ± 3.16% on the first and fourth postoperative day, respectively. Global strain was still reduced on the 30th postoperative day, but had returned to preoperative values 6 months after surgery. Absolute values and relative changes in global strain did not correlate with postoperative peak troponin T measurements. Strain of the inter-ventricular septum was unaffected by surgery as opposed to reference segments, although septal displacement in the longitudinal direction decreased from 12.0 ± 3.75 mm preoperatively to 3.58 ± 4.22 mm 4 days after surgery.

CONCLUSIONS

Global peak longitudinal strain was reduced for at least 30 days after on-pump cardiac surgery and seems to represent a more sensitive marker of myocardial function than ejection fraction. The decrease in global strain was not reflected in troponin T measurements. The visual, echocardiographic impression of septal dysfunction may be a translational phenomenon, as septal strain was unaffected by surgery.

Efficacy of longitudinal speckle tracking strain in conjunction with isometric handgrip stress test for detection of ischemic myocardial segments

BACKGROUND

Isometric handgrip stress test is a simple method for detecting coronary artery disease (CAD). However, the value of this method alone is limited by relatively low sensitivity. This study thus aimed to investigate the usefulness of two-dimensional speckle-tracking strain combined with handgrip for CAD patients.

METHOD

We studied 35 patients with stable angina pectoris who underwent percutaneous coronary intervention (PCI). Longitudinal (L-ɛ) and transverse peak systolic (T-ɛ) strains were measured from three standard apical views before and 1 month after PCI. Segments corresponded to perfusion territories of coronary arteries were divided into two groups based on coronary angiography results: stenotic (S) and nonstenotic (NS) segment.

RESULTS

L-ɛ in S segments increased significantly after PCI, from -15.8% to -17.6% (P < 0.01), but not in NS segments. Moreover, L-ɛ in S segments increased significantly during handgrip before PCI, from -15.8% to -17.6% (P < 0.01), but decreased after PCI, from -17.6% to -16.7% (P = 0.02). In contrast, L-ɛ in NS segments decreased significantly during the isometric handgrip stress test before and after PCI (P < 0.05). Especially noteworthy is that a relative change in L-ɛ of >1.2% during handgrip before PCI could detect significant coronary stenosis with a sensitivity of 80%, specificity of 66%, and area under the curve of 0.77 (P < 0.001). On the other hand, no significant changes were observed in either T-ɛ segments during handgrip either before or after PCI.

CONCLUSION

Longitudinal speckle-tracking strain combined with handgrip may constitute a valuable tool for detection of ischemic myocardial segments and prediction of improvement of regional contraction after revascularization.