The multiple clinical applications of using EchoGo for global longitudinal strain
- | By Ultromics
Left Ventricular (LV) systolic function is typically assessed using LV ejection fraction (EF) and LV volumes, but there is now a case to be made for considering myocardial strain as an additional metric to predict clinical outcomes.
Particularly as the abilities of artificial intelligence (AI) and machine learning (ML) platforms can be used in clinical practice to automate analysis and standardize measurements, meaning that it eliminates variations between operators. AI is becoming commonplace in echocardiography and medicine in general.
The ML and AI built into EchoGo by Ultromics are already able to produce accurate and precise echo measurements with zero variability between operators through its unique ability to automate the entire analysis using AI in the cloud – for traditional LV EJ measurements, as well as for Global Longitudinal Strain (GLS) and Regional Longitudinal Strain (RLS).
Clinical Uses of Global Longitudinal Strain (GLS)
Strain measurements with EchoGo are being utilized across a variety of clinical applications in echocardiography.
The quantitative diagnostic and prognostic indicators produced by EchoGo are so accurate and precise, they have been proven to accurately correlate to a patient’s known outcome better than manual analysis alone .
Additionally, where post-acquisition analysis of echocardiograms have largely depended on the practitioner and the analysis package used in the past, EchoGo now eliminates such subjectivity and decreases the processing time required at every step of the clinical post-processing pipeline.
This rapid yet reliable analysis of echocardiograms can be used as a diagnostic tool across a wide range of clinical applications, including cardiotoxicity, heart failure, and even COVID-related complications.
Coronary Artery Disease and GLS
New guidelines have recommended measuring global longitudinal strain (GLS) when using echo to detect and assess coronary artery disease (CAD). The new guidelines for Non-Invasive Imaging in Coronary Syndromes, published in December 2021, outlines the recommendations from the European Association of Cardiovascular Imaging and the American Society of Echocardiography.
“Echocardiography is most frequently used in patients with CAD to assess global and regional systolic function at rest or during stress. Global systolic function is commonly evaluated by measurement of the LV ejection fraction (LVEF),” said the authors.
However, strain echocardiography is more sensitive in detecting LV dysfunction than LVEF in a variety of myocardial diseases, including ischaemia, one of the main manifestations of CAD.
“The subendocardial longitudinally oriented muscle fibres are most vulnerable to ischaemia, and assessment of GLS at rest has, therefore, shown superiority to wall motion analysis in acute coronary syndromes,” said the paper.
Cardiotoxicity and GLS
As more people are able to survive and recover from cancer than ever before, we are seeing a rise in cardiotoxicity cases. A range of chemotherapy regimens and cardio-toxic cancer drugs can lead to side effects related to LV function , so regular cardiac monitoring to identify issues earlier is more vital than ever.
The EACVI/ASE/Industry Task Force recommends reporting strain as the default parameter, with additional parameters reported as needed , and the British Society of Echocardiography (BSE) suggests measuring GLS in all cardio-oncology cases going forward, as EF alone may not detect subtle, early myocardial injuries . Whereas GLS is a better marker of cardiotoxicity, as it is deemed to be a more sensitive and reproducible measure of LV systolic function .
A recent study  backs up the effectiveness of GLS as a cardiotoxicity measure, even highlighting its predictive abilities for cancer therapy-related cardiac dysfunction (CTRD).
Cancer patients with normal LVEF and decreased baseline GLS were found to more likely develop CTRD, and patients with baseline GLS abnormalities were shown to have a statistically significant increase in CV-related mortality. Furthermore, a baseline GLS of >-18% was associated with a more than four-fold increase for risk of CTRD.
Heart Failure and GLS
GLS can also be used to better predict clinical outcomes in heart failure patients. A 2021 study  highlighted not just the association between GLS and Heart Failure (HF) severity, but it also found, during a median follow up period of just over three years, that GLS is predictive of all-cause mortality and cardiac death.
Approximately half of heart failure patients have a left ventricular ejection fraction (LVEF) that is not markedly abnormal, HF with preserved ejection (HFpEF). GLS is a prognostic indicator in HF patients with preserved ejection fraction and can add incremental value to EF in the prediction of adverse outcomes.
This further confirms the findings of a 2019 evidence review , which showed GLS to have greater prognostic value than LVEF, and adds incremental value to EF in the prediction of adverse outcomes.
COVID-19 and GLS
Along with traditional cardiac applications, GLS has recently been useful as a cardiovascular prognostication tool in patients with COVID-19.
Research discussed as a Late-Breaking Clinical Trial at the ACC.21 Scientific Sessions and published in The Journal of the American Society of Echocardiography has revealed key insights into the varying international use of cardiac ultrasound on COVID-19 patients, and how AI-derived heart measurements were able to predict COVID-19 mortality. This international effort was supported in partnership by the American Society of Echocardiography (ASE), MedStar Health, University of Chicago and Ultromics.
The study looked at the crossover between COVID-19 and cardiac measurements among 870 patients from 13 medical centers in nine countries. Using Ultromics' software to anonymize echocardiograms, upload them to a cloud platform, and use artificial intelligence to quickly and accurately analyze each exam.
Left ventricular longitudinal strain (LV LS) was independently associated with mortality, while left ventricle ejection fraction (LVEF) was not. Furthermore, fully automated quantification of LVEF and LVLS using AI minimized variability, and AI-based LV analyses were significant predictors of in-hospital and follow-up mortality, whereas manual analyses were not.
Using AI for Strain in Your Lab
The clinical applications don’t end there either. EchoGo’s AI-enabled strain analysis could provide additional information that leads to improved accuracy in multiple areas, including:
- Athletic heart
- Hypertrophic cardiomyopathies
- Hypertensive hypertrophy
- Fabry disease
- Myocardial infarction
- Takotsubo cardiomyopathy
- Aortic stenosis
- Duchenne muscular dystrophy
There is mounting evidence supporting the use of strain analysis in clinical analysis, with AI solutions reducing variability and risk of bias, whilst saving time and resources for clinicians in the echo department.
As an additional incentive for cardiologists in the US, myocardial strain imaging is now fully reimbursable using the Category 1 CPT code +93356 – the first echocardiography service to achieve CPT Category 1 status in years.
Ultromics’ vendor-neutral platform, EchoGo, is at the forefront of this revolution. It can be connected through the cloud and set up quickly with no special training, making Ultromics’ strain analysis a simple, efficient, and cost-effective choice for healthcare institutions.
- Bunting KV, Steeds RP, Slater LT, et al. A Practical Guide to Assess the Reproducibility of Echocardiographic Measurements. Journal of the American Society of Echocardiography. 2019;32(12):1505–15.
- McGowan JV, Chung R, Maulik A, Piotrowska I, Walker JM, Yellon DM. Anthracycline Chemotherapy and Cardiotoxicity. Cardiovascular Drugs and Therapy. 2020;31(1):63–75.
- Voigt JU, Pedrizzetti G, Lysyansky P, et al. Definitions for a common standard for 2D speckle tracking echocardiography: consensus document of the EACVI/ASE/Industry Task Force to standardize deformation imaging. European Heart Journal - Cardiovascular Imaging. 2014;16:1–11.
- Liu JE, Barac A, Thavendiranathan P, Scherrer-Crosbie M. Strain Imaging in Cardio-Oncology. JACC: CardioOncology. 2020;2(5):677–89.
- The journal of the British Society of Echocardiography. Conference Report. British Society of Echocardiography. 2020.
- Araujo-Gutierrez R, Chitturi KR, Xu J, Wang Y, et al. Baseline global longitudinal strain predictive of anthracycline-induced cardiotoxicity. Cardio-Oncology. 2021;7(1).
- Tröbs SO, Prochaska JH, Schwuchow-Thonke S, et al. Association of Global Longitudinal Strain With Clinical Status and Mortality in Patients With Chronic Heart Failure. JAMA Cardiology [Internet]. 2021;6:448–56.
- Ashish K, Faisaluddin M, Bandyopadhyay D, Hajra A, et al. Prognostic value of global longitudinal strain in heart failure subjects: A recent prototype. IJC Heart & Vasculature. 2019;22:48–9.