Quantification Of Left Ventricular Ejection Fraction Research Articles

Harnessing the Power of AI: A Comprehensive Review of Left Ventricular Ejection Fraction Assessment With Echocardiography.

The quantification of left ventricular ejection fraction (LVEF) has important clinical utility in the assessment of cardiac function and is vital for the diagnosis of cardiovascular diseases. A transthoracic echocardiogram serves as the most commonly used tool for LVEF assessment for several reasons, including, its noninvasive nature, great safety profile, real-time image processing ability, portability, and cost-effectiveness. However, transthoracic echocardiogram is highly dependent on the clinical skill of the sonographer and interpreting physician. Moreover, even amongst well-trained clinicians, significant interobserver variability exists in the quantification of LVEF. In search of possible solutions, the usage of artificial intelligence (AI) has been increasingly tested in the clinical setting. While AI-derived ejection fraction is in the preliminary stages of development, it has shown promise in its ability to rapidly quantify LVEF, decrease variability, increase accuracy, and utilize higher-order processing capabilities. This review will delineate the latest advancements of AI in evaluating LVEF through echocardiography and explore the challenges and future trajectory of this emerging domain.

Evaluation of the image quality and validity of handheld echocardiography for stroke volume and left ventricular ejection fraction quantification: a method comparison study.

Bedside quantification of stroke volume (SV) and left ventricular ejection fraction (LVEF) is valuable in hemodynamically compromised patients. Miniaturized handheld ultrasound (HAND) devices are now available for clinical use. However, the performance level of HAND devices for quantified cardiac assessment is yet unknown. The aim of this study was to compare the validity of HAND measurements with standard echocardiography (SE) and three-dimensional echocardiography (3DE). Thirty-six patients were scanned with HAND, SE and 3DE. LVEF and SV quantification was done with automated software for the HAND, SE and 3DE dataset. The image quality of HAND and SE was evaluated by scoring segmental endocardial border delineation (2 = good, 1 = poor, 0 = invisible). LVEF and SV of HAND was evaluated against SE and 3DE using correlation and Bland-Altman analysis. The correlation, bias, and limits of agreement (LOA) between HAND and SE were 0.68 [0.46:0.83], 1.60% [-2.18:5.38], and 8.84% [-9.79:12.99] for LVEF, and 0.91 [0.84:0.96], 1.32ml [-0.36:4.01], 15.54ml [-18.70:21.35] for SV, respectively. Correlation, bias, and LOA between HAND and 3DE were 0.55 [0.6:0.74], -0.56% [-2.27:1.1], and 9.88% [-13.29:12.17] for LVEF, and 0.79 [0.62:0.89], 6.78ml [2.34:11.21], 12.14ml [-26.32:39.87] for SV, respectively. The image quality scores were 9.42 ± 2.0 for the apical four chamber views of the HAND dataset and 10.49 ± 1.7 for the SE dataset and (P < 0.001). Clinically acceptable accuracy, precision, and image quality was demonstrated for HAND measurements compared to SE. In comparison to 3DE, HAND showed a clinically acceptable accuracy and precision for LVEF quantification.

Hocus POCUS! Parental Quantification of Left-Ventricular Ejection Fraction Using Point of Care Ultrasound: Fiction or Reality?

Point of care ultrasound has become increasingly utilized in pediatric settings. The assessment of cardiac function is one such implementation of this. This study aimed to determine the feasibility of parents in acquiring images to assess function using a handheld ultrasound probe and the correlation of fractional shortening measurements by handheld ultrasound with hospital acquired echocardiography. This was a single-center prospective study of parents of pediatric patients admitted to the hospital. Parents underwent a 25-min education session on how to use the handheld ultrasound probe and then were asked to acquire a parasternal short-axis and apical four-chamber image on their own. Acquired images were reviewed by two physicians to determine adequacy of images to assess systolic cardiac function subjectively and objectively. Fractional shortening was measured using parent-acquired images and then compared to recent hospital acquired fractional shortening. A total of 25 parents of 21 patients enrolled and completed the study. Of the enrolled parents, 96% of both parasternal short-axis and apical four-chamber images acquired were deemed appropriate for subjective assessment of systolic function. Inter-reader variability of fractional shortening was moderate between two readers. Correlation of fractional shortening measured from parent-acquired images versus hospital acquired images was moderate. Parents were able to successfully obtain a parasternal short-axis and apical four-chamber image adequate to assess function and quantify fractional shortening after a 25-min education session. This pilot data demonstrate that further exploration of parent-performed point of care cardiac assessment may be warranted.

MR Multitasking-based multi-dimensional assessment of cardiovascular system (MT-MACS) with extended spatial coverage and water-fat separation.

To extend the MR MultiTasking-based Multidimensional Assessment of Cardiovascular System (MT-MACS) technique with larger spatial coverage and water-fat separation for comprehensive aortocardiac assessment. MT-MACS adopts a low-rank tensor image model for 7D imaging, with three spatial dimensions for volumetric imaging, one cardiac motion dimension for cine imaging, one respiratory motion dimension for free-breathing imaging, one T2-prepared inversion recovery time dimension for multi-contrast assessment, and one T2*-decay time dimension for water-fat separation. Nine healthy subjects were recruited for the 3T study. Overall image quality was scored on bright-blood (BB), dark-blood (DB), and gray-blood (GB) contrasts using a 4-point scale (0-poor to 3-excellent) by two independent readers, and their interreader agreement was evaluated. Myocardial wall thickness and left ventricular ejection fraction (LVEF) were quantified on DB and BB contrasts, respectively. The agreement in these metrics between MT-MACS and conventional breath-held, electrocardiography-triggered 2D sequences were evaluated. MT-MACS provides both water-only and fat-only images with excellent image quality (average score=3.725/3.780/3.835/3.890 for BB/DB/GB/fat-only images) and moderate to high interreader agreement (weighted Cohen's kappa value=0.727/0.668/1.000/1.000 for BB/DB/GB/fat-only images). There were good to excellent agreements in myocardial wall thickness measurements (intraclass correlation coefficients [ICC]=0.781/0.929/0.680/0.878 for left atria/left ventricle/right atria/right ventricle) and LVEF quantification (ICC=0.716) between MT-MACS and 2D references. All measurements were within the literature range of healthy subjects. The refined MT-MACS technique provides multi-contrast, phase-resolved, and water-fat imaging of the aortocardiac systems and allows evaluation of anatomy and function. Clinical validation is warranted.

Assessment and validation of a novel fast fully automated artificial intelligence left ventricular ejection fraction quantification software.

Quantification of left ventricular ejection fraction (LVEF) by transthoracic echocardiography (TTE) is operator-dependent, time-consuming, and error-prone. LVivoEF by DIA is a new artificial intelligence (AI) software, which displays the tracking of endocardial borders and rapidly quantifies LVEF. We sought to assess the accuracy of LVivoEF compared to cardiac magnetic resonance imaging (cMRI) as the reference standard and to compare LVivoEF to the standard-of-care physician-measured LVEF (MD-EF) including studies with ultrasound enhancing agents (UEAs). In 273 consecutive patients, we compared MD-EF and AI-derived LVEF to cMRI. AI-derived LVEF was obtained from a non-UEA four-chamber view without manual correction. Thirty-one patients were excluded: 25 had interval interventions or incomplete TTE or cMRI studies and six had uninterpretable non-UEA apical views. In the 242 subjects, the correlation between AI and cMRI was r=.890, similar to MD-EF and cMRI with r=.891 (p=0.48). Of the 126 studies performed with UEAs, the correlation of AI using the unenhanced four-chamber view was r=.89, similar to MD-EF with r=.90. In the 116 unenhanced studies, AI correlation was r=.87, similar to MD-EF with r=.84. From Bland-Altman analysis, LVivoEF underreported the LVEF with a bias of 3.63 ± 7.40% EF points compared to cMRI while MD-EF to cMRI had a bias of .33 ± 7.52% (p=0.80). Compared to cMRI, LVivoEF can accurately quantify LVEF from a standard apical four-chamber view without manual correction. Thus, LVivoEF has the ability to improve and expedite LVEF quantification.

336 Efficacy With Use of Ultrasound Enhancing Agents at the Townsville Hospital

The use of Ultrasound Enhancing Agents (UEAs) has become an integral part in Echocardiography. The Cardiac Investigation Unit (CIU) at the Townsville Hospital uses Definity. The indications are left ventricular (LV) opacification and delineation of LV endocardial border but off-label clinical applications are very useful in clinical echocardiography. The only contraindication is hypersensitivity to perflutren. Aim of our study is to demonstrate the indications, effectiveness and influence on clinical decision making using UEAs in echocardiography. This is an audit of UEA use in echocardiograms done in CIU during 2017. 202 echocardiograms were examined. The demographics revealed 73% of the patients were male; median age was 62. Transthoracic echocardiograms were majority (79%), with stress-echocardiogram (20%) and trans-oesophageal echocardiogram (1%). 46% were outpatients and the rest were inpatients [CCU (24%), Wards (10%), and ICU (2%)]. Indications were enhancement of endocardial definition (80%), quantification of LV ejection fraction and LV volumes (59%), assessment of LV apex (24%), exclusion of intra-cardiac masses (12%), and Doppler enhancement (2.5%). The success rates were 95%, 96%, 98%, 90% and 69% respectively. Clinical implications showed no change in management (79%), medication change (9%), procedural change (7%), changes in both (2%) and inadequate imaging (3%). Only one patient had complication as back pain. Use of UEAs in our Echo Lab has shown to be very effective in multiple clinical applications, avoiding other down-stream investigations without causing major complications. It also helps in clinical decision making leading to changes in management in 18% of the cases.

Abstract 260: Congruence of Speckle Tracking Echocardiography and Magnetic Resonance Imaging Assessment of Left Ventricular Ejection Fraction

Background: Assessment of left ventricular ejection fraction (LVEF) is an important aspect of diagnosing and treating patients with cardiovascular disease. While cardiac MRI is considered the gold standard for assessing LVEF, high cost and patient risk has precluded routine use of MRI in clinical practice. Echocardiography is a common non-invasive, safe, and economic method for assessing LVEF. Traditionally, these measures required making visual determinations, resulting in wide variations in LVEF estimates. Using calculations from global longitudinal peak strain (GLPS) in speckle tracking echocardiography (STE) might reduce variability in estimations of LVEF and enhance treatment decision-making. To examine whether STE GLPS compared to cardiac MRI provides clinically acceptable variation in LVEF estimations, the congruence between GLPS in STE and cardiac MRI was examined. Methods: At a single Midwestern regional referral center, medical records were abstracted for inpatients and outpatients with a first-listed cardiovascular disease diagnosis who were ≥18 years of age and who were evaluated using speckle tracking echocardiogram and magnetic resonance imaging procedures within a 30-day period between January, 2011 and May, 2014. Demographic and relevant clinical variables that might affect echocardiographic and MRI quality and interpretation were extracted from medical records. Overall agreement between LVEF estimates from cardiac MRI and from STE GLPS was assessed using the concordance correlation coefficient, Bland-Altman analysis, and weighted Kappa. The influence of demographic and co-morbidity factors on the agreement was also assessed using multivariable regression analysis. Results: A total of 93 patient medical records (48 males; age 59±18 years) underwent both STE and MRI within a maximum 30-day period. For quantification of LVEF, STE correlated well with MRI (r=0.73; CCC=0.67), but LVEF was significantly underestimated (bias=6.8%), with wide limits of agreement (-17% to 31%). Categorization of LVEF into four classes, ranging from severely impaired to normal, resulted in a weighted kappa of 0.65 (95% CI: 0.53, 0.77). The difference between MRI and STE increased with increasing BMI (b=0.48, P=.01), and this difference was greater for those with hypertension (mean=9.5) than those without hypertension (mean=3.8, P=.02). Discussion and Conclusions: While these two measures indicate moderate to substantial agreement, STE-derived LVEF was underestimated in most patients compared with MRI. The magnitude of STE underestimation was positively associated with both BMI and hypertension. Further research is needed on technological developments in echocardiography, as well as interventions focused on addressing inter-observer agreement variability and treatment decision-making to effectively achieve desired clinical outcomes.

Utilisation of three-dimensional echocardiographic, semi-automated, left ventricular ejection fraction quantification by cardiac nurses: a comparison to cardiac magnetic resonance imaging

Utilisation of three-dimensional echocardiographic, semi-automated, left ventricular ejection fraction quantification by cardiac nurses: a comparison to cardiac magnetic resonance imaging

Accuracy of an operator-independent left ventricular ejection fraction quantification algorithm (Auto LVQ) with three-dimensional echocardiography: a comparison with cardiac magnetic resonance imaging

Accuracy of an operator-independent left ventricular ejection fraction quantification algorithm (Auto LVQ) with three-dimensional echocardiography: a comparison with cardiac magnetic resonance imaging

PM428 Accuracy and reproducibility of completely automated 3-dimensional left ventricular ejection fraction quantification

Introduction: Ischemic heart disease is the most important cause of cardiac morbidity and death. Early detection of cardiac deterioration is imperative. To reach a large population safe, easy accessible and reliable non-invasive investigation methods are required. Objectives: Speckle-tracking echocardiography is a new technique founded on pure 2D gray scale ultrasound acquisition and provides non-doppler, angle-independent and objective quantification of myocardial deformation and of left ventricular systolic and diastolic dynamics. Left ventricular dysfunction is a sensitive predictor of cardiovascular atherosclerotic diseases. Methods:We investigated 969 male, self-supporting and ambulant patients, divided in 495 healthy subjects (HS) with documented normal coronary arteries and in 474 coronary patients (CP), treated with multiple stent implantation or bypass surgery. Both groups were divided in three age groups: 40-59y, 60-79y and 80-99y. We measured by speckle-tracking echocardiography the “global longitudinal peak systolic strain average” (GLPSSavg) of the left ventricle, divided in 24 segments, and also the “average peak longitudinal strain of the 5 myocardial segments with the lowest strain values” (Avg5LSS). The more negative the strain value, the better the myocardial contractile reserve. Measurement of sum maximal diameter left atrium plus maximal diameter left ventricle in cm (LALV). Results: For all age groups significant decrease (p1⁄40,000) of GLPSSavg in CP compared with HS but quasi unchanged results with aging. Also statistically significant decrease (p1⁄40,000) of Avg5LSS for all age groups in CP compared with HS but with a tendency to a progressive decrease of Avg5LSS with aging. LALV is in all age groups statistically significantly larger (p1⁄40,000) in CP compared with HS. Progressive increase of LALV with aging. (Table 1)