Endocardial Border Delineation Research Articles

Deep learning for quantification of myocardial scar and microvascular obstruction in late gadolinium enhancement cardiovascular magnetic resonance images

Abstract Objectives Detecting and measuring myocardial scar and microvascular obstruction (MVO) accurately following reperfusion therapy is clinically vital for patients with acute myocardial infarction (AMI). Current clinical practice relies on manual delineation of endocardial borders as well as hyper- and hypo-enhanced regions on late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) images for scar and MVO quantification, respectively. However, this approach is subjective, labor-intensive, and time-consuming. The objective of this study is to develop and assess a convolutional neural network (CNN)-based method for the automated quantification of LGE scar and MVO in AMI patients. Methods A total of 1836 LGE images from 252 patients with AMI were analyzed, with the cohort comprising 232 males and an average age of 56±9 years. Our approach, utilizing a combined architecture of cascaded YOLOv8 (You Only Look Once version 8) and nnU-Net, was implemented for the simultaneous segmentation of the left ventricular (LV) myocardium, scar, and MVO in LGE images. Independent datasets for training, validation, and testing were maintained in an 8:1:1 ratio. Performance evaluation was conducted by comparing the results to manual scar and MVO quantification, utilizing metrics such as the Dice similarity coefficient (DSC) and Bland-Altman analysis. Results The automated segmentation process took 0.05 seconds per image. The segmentation accuracy, as assessed by the DSC, yielded values of 0.96±0.04 (per-patient, n=25) and 0.96±0.05 (per-slice, n=184) for scar segmentation, and 0.86±0.17 (per-patient) and 0.89±0.15 (per-slice) for MVO segmentation. In per-patient analysis, the volumes of automatically segmented scar and MVO demonstrated strong agreement with manually derived results, with biases [limits of agreement] of -0.3 [-3.0, 2.4] cm³ and 0.1 [-0.2, 0.3] cm³, respectively. Furthermore, there was strong concordance between automatically and manually derived scar size as a percentage of LV mass (-0.2 [-3.1, 2.7] %) and MVO size as a percentage of scar (1.2 [-5.6, 8.0] %). Conclusions The findings demonstrate excellent agreement between our proposed automated deep-learning solution and clinical expert annotation, suggesting its potential as a predictive tool for prognosis and clinical outcomes in patients with AMI.

Global longitudinal strain measurement in the modern era - is artificial intelligence the answer ?

Abstract Background Global longitudinal strain (GLS) enhances the assessment of left ventricular (LV) function beyond ejection fraction (EF) in 2D echocardiography (Echo). However, manual GLS measurement, the most common technique, is operator dependent. A novel vendor-independent artificial intelligence (AI)-based software streamlines automated 2D-Echo exam evaluation and GLS calculation. Purpose We sought to evaluate the ability of the AI to automatically identify LV 4-, 2-, and 3-chamber views (CV) from 2D-Echo exams and to validate GLS against the conventional manual method. Methods 540 patients underwent standard 2D-Echo exams. The server-based AI recognized the optimal LV CVs from 2D-Echo exams and automatically calculated triplane GLS by endocardial delineation (n=489, 91%). Manual LV GLS was performed independently by accredited cardiologists. Pearson’s correlation (R) and Bland-Altman analysis were performed to assess bias and limits of agreement (LOA) for GLS. Multivariate between-method regression was performed using ordinary least squares to disclose possible sources of possible bias. Significance was defined as a 2-tailed P value < 0.05. Results Patients’ median age was 70 years [18-93], 59% were males. The 2D-Echo indications were coronary artery disease (36%), valvular heart disease (15%), non-ischemic heart failure (15%) and others (34%). The feasibility of the AI to calculate GLS was 91% (n=489) due to endocardial border delineation issues. AI correctly classified all CVs. An excellent correlation (r=0.92, p<0.001) was observed between AI and manual GLS, with low bias (0.5%) and narrow LOAs (-3.1 and +4.2%) (Figure 1, top row). We identified LV end-diastolic volume and EF as statistically significant confounders (p < 0.05) with only small effect as depicted in Figure 1 (bottom row). Neither sex, age, acoustic window, body mass index, nor heart rate, along with the interaction with sex, end-diastolic volume, or EF, were significant (p > 0.23). Conclusion AI-based LV GLS calculation in 2D-Echo shows promising feasibility and accuracy. Strong agreement between AI-derived GLS and manual measurements supports its reliability. The AI's ability to identify optimal LV views underscores its robustness. Further validation and refinement are warranted, highlighting the transformative potential of AI in advancing cardiovascular diagnostics.

Ultrasound-Enhancing Agent and IV Administration in Cardiac Sonography: How Sonographers Play a Key Role in Positively Affecting Key Performance Indicators

As the health system in the United States continuously searches for ways to reduce costs and improve the health care experience, cardiac sonographers are uniquely positioned to add to this initiative. Tasked with providing high-quality imaging studies in outpatient and inpatient areas, the scope of practice for sonographers continues to evolve. To ensure quality imaging, ultrasound-enhancing agents (UEAs) are needed in patients with suboptimal images to improve delineation of left ventricular endocardial borders. This process involves intravenous (IV) access and occurs in both patients in ambulatory clinics and hospitals. Historically, health care professionals delegated to perform these duties have been nursing, radiology, and nuclear medicine staff. Because these professionals have their own job responsibilities, the potential to complete a transthoracic echocardiogram (TTE) with UEA, in a timely fashion, may be compromised. Expanding the practice of cardiac sonographers to include these duties should be supported to facilitate uninterrupted patient care, efficiency, and stakeholder satisfaction.

Abstract 15929: Safety Profile of Ultrasound Enhancing Agents in Echocardiography Across Yale New Haven Health System

Background: Ultrasound Enhancing Agents (UEAs) are increasingly used in echocardiography for delineation of endocardial border and detection of left ventricular (LV) thrombus with reported rate of serious adverse reactions from 0 to 0.029%. Contemporary utilization and safety data of UEA in echocardiography are scarce. Aims: We aimed to obtain contemporary data on comparative safety of UEA Lumason and Definity in inpatient and outpatient settings across large academic healthcare system. Methods: A retrospective database analysis of all echocardiograms performed within Yale New Haven Health System (YNHHS) between January 1, 2019 to December 31, 2022 was done. Echocardiography reporting software captured type of UEA as well as any observed adverse reaction. All reported adverse events were manually chart reviewed through electronic medical record for confirmation and grading severity. American College of Radiology (ACR) criteria for contrast agent reaction were used for grading to mild, moderate, or severe reaction. Adverse reactions differences were analyzed with Pearson’s chi-square and predictors were identified by Logistic regression. Results: Out of 305,749 echocardiograms 91,215 (29.83%) required UEAs. In total, 430 (0.47%) adverse events were reported. Lumason (49216, 54.42%) and Definity (41077, 45.42%) were mainly used agents with 158 (0.32%) and 270 (0.66%) reactions recorded, respectively (p<0.001). There were more mild reactions with Definity (245, 0.6%) Vs Lumason (124, 0.25%) (p <0.001), and more severe reaction with Lumason (13, 0.026%) Vs Definity (3, 0.007%) (p=0.0322). Females had higher chance of having any form of contrast reaction (OR 1.707; 95% CI: 1.412-2.065). Older age (OR 0.984 per 1 year; p <0.0001) and higher heart rate (OR 0.993 per 1 bpm; P = 0.050) were associated with a decreased chance of reaction. Ejection fraction and body mass index were not associated with adverse events. Conclusion: UEAs are frequently used in routine echocardiography studies. Adverse reactions to UEA were rare and mostly mild. Severe reactions were more frequent with Lumason than Definity. Female sex, younger age and lower heart rate were associated with increased incidence of adverse reactions.

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.

Comparison of two ultrasound contrast agents for left ventricular opacification

Abstract Funding Acknowledgements Type of funding sources: None. Background Several ultrasound contrast agents have been approved and used for measurement of LV volumes and ejection fraction (EF). However, there has been no direct comparison between these agents. Purpose To compare different imaging parameters between two widely used ultrasound contrast agents for LV opacification when imaged with a low power contrast specific imaging modality Methods A retrospective study was performed using recordings of the local echocardiography registry for patients undergoing chemotherapy for cancer treatment. Patients were included who underwent follow-up echocardiograms (3 months) with 2 different ultrasound contrast agents and had only minor changes in the LV ejection fraction (EF) between the studies (&amp;lt;5%). Qualitative and quantitative analysis of the contrast effect was performed in apical four- and two chamber views (4CV,2CV). For quantitative analysis of the LV opacification square regions of interest (ROI) were placed in the apical and basal regions of the ventricle in each echocardiographic recording and the arithmetic mean and standard deviation of pixel intensity within each ROI was recorded throughout the entire loop. Qualitative visual assessment was performed using a three step visual score in order to assess the endocardial border delineation, basal attenuation and apical swirling. Wilcoxon signed-rank test was used to compare the measurements obtained with different contrast agents. Results 41 patients fulfilled the inclusion criteria. In all patients suitable recordings for measurement of LV volumes and EF were obtained. The mean + standard deviation of the EF was 61 + 9%. Both contrast agents provided intensive LV opacification in the basal and apical cavities. The video intensities (mean + standard deviation) in the apical and basal cavities were comparable across both contrast agents in the 2CV apical ROI (219.96 + 21.42 vs 224.69 + 20.23, p = 0.32), the 2CV basal ROI (114.55, 42.02 vs 112.79, 42.57, p = 0.81), the 4CV apical ROI (228.02, 17.80 vs 225.51, 20.37, p = 0.30), and the 4CV basal ROI (100.05, 41.11 vs 92.84, 42.54, p = 0.37). Visual assessment of endocardial delineation on end-diastolic and end-systolic frames revealed no statistical difference between the contrast agents. Conclusion In patients with normal LV function no clinically relevant differences were found between the two contrast agents regarding LV opacification and endocardial border delineation.

The odyssey to dethrone LV ejection fraction continues: the prognostic value of LV global function index in heart failure

Abstract Background Left Ventricular (LV) Global Function index (LVGFi) is a parameter that combines data from global systolic performance and volumetric anatomical information, measurable by non-contrast Cardiac Magnetic Resonance (CMR). We aimed to evaluate whether LVGFi predicts major cardiovascular outcomes and outperforms LV ejection fraction (LVEF) in Heart Failure (HF). Methods We conducted a retrospective single-centre study of consecutive patients with HF who were referred to and had a LVEF &amp;lt;50% at CMR. Other than inadequate images for endocardial or epicardial border delineation, there were no exclusion criteria. LVEF was determined by 3D measurement. LVGFi was calculated as the LV stroke volume to the LV global volume ratio (Figure 1). The primary endpoint was a composite of time to all-cause death or HF hospitalization. Results The cohort was comprised of 433 HF patients (mean age 64±12 years, 74.1% male, ischaemic HF 53.1%, NYHA I-II 83.9%) with a mean LVEF of 33.5±10.0% and LVGFi of 22.8±7.4%. Over a median follow-up of 27 (17–37) months, 85 (19.6%) met the primary endpoint and 42 (9.7%) died. Patients with an event of the primary endpoint had markers of more severe HF, as noted by a reduced functional capacity (NYHA I-II: 63.5 vs. 89.0%; p&amp;lt;0.001) and increased natriuretic peptides [NT-proBNP: 2664 (1022–27242) vs. 791 (337–7258); p&amp;lt;0.001). Likewise, CMR showed higher LV volumes (e.g., LV end-diastolic volume index: 137±50 vs. 120±43mL/m2; p=0.001) and reduced LV performance indices, namely LVEF (29.2±10.6 vs 34.5±9.6%; p&amp;lt;0.001) and LVGFi (19.8±7.4 vs 23.6±7.3%; p&amp;lt;0.001). Both LVEF and LVGFi independently predicted the primary endpoint in multivariate analysis (separately imputed into a model adjusted for NYHA, NT-proBNP and creatinine). The LVEF model was more powerful than that of LVGFi. Similarly, LVGFi did not provide incremental prognostic information over LVEF in c-statistics analysis (0.653 vs. 0.622; p=0.645) (Figure 2). Conclusion While LVGFi independently predicted major outcomes in patients with HF and LVEF &amp;lt;50%, it did not surpass LVEF. Our findings contrast to those demonstrating LVGFi as a powerful variable that outperforms LVEF in hypertrophic cardiomyopathy, cardiac amyloidosis, and healthy subjects at risk of developing structural heart disease. We hypothesize that LVGFi might be primarily useful in the prognostic stratification of patients with preserved LVEF. Funding Acknowledgement Type of funding sources: None. Figure 1Figure 2

Stress-echocardiography or coronary computed tomography in suspected chronic coronary syndrome after the 2019 European Guidelines? A practical guide.

Stress-echocardiography can rightly be considered one of the champions of cardiac functional imaging, thanks to its real-time imaging, high temporal resolution, high safety and very low cost. When stress-echocardiography is performed at top technical quality, hence taking advantage of ultrasound contrast media for endocardial border delineation at least for suboptimal cases, subjectivity is minimized, and with the routine use of coronary flow reserve measurement (left anterior descending coronary artery, stress/rest ratio reduced or normal, i.e. <>2.0) diagnostic sensitivity is strengthened. The true competitor of any type of functional imaging, stress-echocardiography included, is nowadays coronary computed tomography angiography, which is instead a diagnostic method directly, noninvasively assessing coronary anatomy, apparently the holy grail for any cardiologist. The new 2019 Guidelines on chronic coronary syndrome of the European Society of Cardiology change the existing landscape and clinical practice, while they probably cannot clarify which type of test, functional or anatomic, should be first chosen in different clinical scenarios of suspected chronic coronary syndrome. We review the existing data and the authors' personal view in order to assess how functional stress-echocardiography compares with coronary computed tomography angiography regarding three main aspects: diagnosis of coronary artery disease, guidance of therapy (coronary revascularization versus medical therapy) and risk stratification.

T1 mapping-derived signature of myocardial involvement in idiopathic inflammatory myopathy compared to acute viral myocarditis: a texture-based analysis

Abstract Funding Acknowledgements Type of funding sources: None. Background. Recent studies revealed the ability of MRI T1 mapping to characterize myocardial involvement in both idiopathic inflammatory myopathy (IIM) and acute viral myocarditis (AVM), as compared to healthy controls. However, neither myocardial T1 nor T2 maps were able to discriminate between IIM and AVM patients, when considering conventional myocardial mean values and derived indices such as lambda and extracellular volume. Purpose. To investigate the ability of T1 mapping-derived texture analysis to differentiate IIM from AVM. Methods. Forty patients, 20 with IIM (51 ± 17 years, 9 men) and 20 with AVM (34 ± 13 years, 16 men) underwent 1.5T MRI T1 mapping using a modified Look-Locker inversion-recovery sequence before and 15 minutes after injection of a gadolinium contrast agent. After manual delineation of endocardial and epicardial borders and co-registration of all inversion time images, native and post-contrast T1 maps were estimated. Myocardial texture analysis was performed on native T1 maps. Textural features such as: autocorrelation, contrast, dissimilarity, energy and sum entropy were used to build a least squares-based linear regression model. Finally, receiver operating characteristic (ROC) analysis was used to investigate the ability of such texture features score to classify IIM vs. AVM patients, compared to the performance of mean myocardial T1. A Wilcoxon rank-sum test was also used to test difference significance between groups. Results. Both native and post-contrast mean myocardial T1 values were comparable between IIM (native: 1022 ± 43 ms; post-contrast: 319 ± 44 ms) and AVM (1056 ± 59 ms, p = 0.07; 318 ± 35 ms, p = 0.90, respectively) groups. Results of ROC analyses are provided in the Table, indicating that a better discrimination between IIM and AVM patients was obtained when using texture features, with higher AUC and accuracy than mean T1 values (Figure). Conclusion. Texture analysis derived from MRI T1 maps without contrast agent injection was able to discriminate between IIM and AVM with higher accuracy, sensitivity and specificity than conventional T1 indices. Such analysis could provide a useful myocardial signature to help diagnose and manage cardiac alterations associated with IIM in patients presenting with myocarditis and primarily suspected of AVM. Table Area under curve (AUC) Accuracy Sensitivity Specificity Native T1 0.67 0.70 0.65 0.75 Post-contrast T1 0.49 0.60 0.25 0.95 Texture features score 0.85 0.82 0.90 0.75 ROC analyses for classification between IIM and AVM patients Abstract Figure

Artificial Intelligence Aids Cardiac Image Quality Assessment for Improving Precision in Strain Measurements

ObjectivesThe aim of this study was to develop an artificial intelligence tool to assess echocardiographic image quality objectively. BackgroundLeft ventricular global longitudinal strain (LVGLS) has recently been used to monitor cancer therapeutics−related cardiac dysfunction (CTRCD) but image quality limits its reliability. MethodsA DenseNet-121 convolutional neural network was developed for view identification from an athlete’s echocardiographic dataset. To prove the concept that classification confidence (CC) can serve as a quality marker, values of longitudinal strain derived from feature tracking of cardiac magnetic resonance (CMR) imaging and strain analysis of echocardiography were compared. The CC was then applied to patients with breast cancer free from CTRCD to investigate the effects of image quality on the reliability of strain analysis. ResultsCC of the apical 4-chamber view (A4C) was significantly correlated with the endocardial border delineation index. CC of A4C >900 significantly predicted a <15% relative difference in longitudinal strain between CMR feature tracking and automated echocardiographic analysis. Echocardiographic studies (n =752) of 102 patients with breast cancer without CTRCD were investigated. The strain analysis showed higher parallel forms, inter-rater, and test-retest reliabilities in patients with CC of A4C >900. During sequential comparisons of automated LVGLS in individual patients, those with CC of A4C >900 had a lower false positive detection rate of CTRCD. ConclusionsCC of A4C was associated with the reliability of automated LVGLS and could also potentially be used as a filter to select comparable images from sequential echocardiographic studies in individual patients and reduce the false positive detection rate of CTRCD.

Novel contrast agent Visphere™ is feasible for contrast-enhanced ultrasonography in dogs.

Contrast-enhanced ultrasonography provides a more functional diagnostic image than conventional ultrasonography. This prospective exploratory study compared the novel contrast agent, Visphere™ , with commercial contrast agents in five healthy Beagle dogs. Visphere™ has the smallest diameter and highest concentration compared with Sonazoid® and SonoVue® . Each dog received an intravenous injection of Visphere™ , Sonazoid® , or SonoVue® . Images were recorded for 300, 600, and 60 s in the heart, liver, and left kidney, respectively. The mean pixel values of the regions of interest for each organ were expressed as time intensity curves (TIC). The agents all improved the visualization of left ventricular endocardial border delineation in the heart, and had similar TICs and clinical useful durations. In contrast, Visphere™ expressed the highest mean pixel value in the liver parenchyma at an early observation time and maintained the intensity until 600 s, like Sonazoid® . The renal evaluation results indicated there were no statistically significant differences in time-to-peak for the renal cortex or medulla among the agents. Compared with the other two agents, SonoVue® had the lowest peak enhancement for the renal cortex and medulla. No dogs had any adverse reactions during or after the study. All three agents provided adequate results for left ventricular endocardial border delineation, and Visphere™ may have the same potential as Sonazoid® to detect and characterize hepatic lesions. Visphere™ and Sonazoid® may offer better visualization quality to evaluate renal function. In conclusion, the novel contrast agent, Visphere™ , is comparable with commercial agents and could be applied in different major organs in dogs.

EFFECT OF DIAGNOSTIC INTERMITTENT HIGH MECHANICAL INDEX IMPULSES DURING AN ULTRASOUND ENHANCING AGENT INFUSION ON GLOBAL AND REGIONAL LONGITUDINAL STRAIN IN PATIENTS WITH ABNORMAL SYSTOLIC FUNCTION

Intermittent high (IH) mechanical index (MI) impulses during transthoracic ultrasound are recommended during very low MI (VLMI) imaging for improving endocardial border delineation following an intravenous injection or infusion of ultrasound enhancing agents (UEAs). These high MI impulses have also

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.

EFFECT OF DIAGNOSTIC INTERMITTENT HIGH MECHANICAL INDEX IMPULSES ON GLOBAL LONGITUDINAL STRAIN IN PATIENTS BEING EVALUATED FOR SIGNIFICANT CORONARY ARTERY DISEASE

Intermittent high (IH) mechanical index (MI) impulses from a transcutaneous diagnostic transducer are used to improve endocardial border delineation and analyze myocardial perfusion during infusion of ultrasound enhancing agents (UEAs) These high MI impulses have also been shown to augment skeletal

Conventional Two-Dimensional Echocardiography Versus Contrast Echocardiography in the Assessment of Left Ventricular Volumes and Function in Patients with Poor Acoustic Window

Aim: To compare the number of left ventricular (LV) segments visualized, detection of regional wall motion, and LV volumes and function with conventional two-dimensional echocardiography versus that with contrast echocardiography in patients with poor acoustic windows. Materials and Methods: This was a prospective study done over a duration of 1 year, on 50 consenting patients with poor echocardiographic image quality. Basic information and baseline echocardiograms were recorded. SonoVue contrast was administered intravenously as per a preset protocol through a peripheral line, and LV endocardial border delineation was recorded in various comparable views. Results: There was a significant change in the quality of the echocardiographic images postcontrast enhancement, with no study images remaining uninterpretable and only 16% remaining technically difficult. The remaining studies became adequate in terms of endocardial border delineation. Myocardial segment visualization changed significantly after contrast, with the number of well-visualized segments per patient improving from 10.66 before contrast to 16.26 after contrast, on average. There was a significant change in the estimation of LV volumes after contrast administration. The biplane ejection fraction was also significantly different after contrast. The study detected new regional wall motion abnormalities in 10 (20%) patients out of the total 50. There was only one case of an adverse event in terms of three isolated ventricular premature complexes in one of the patients after contrast administration. Conclusion: Contrast echo appears to be an easy, safe, and reliable investigation in patients with poor echo windows. Our study shows that endocardial border delineation is best with contrast enhancement, which improves physician's confidence and hence can impact the overall diagnosis, management, and prognosis of patients based on the better and reliable echo findings.

Abstract 15: The Use of Handheld Focused Cardiac Ultrasound (FoCUS) for EF Assessment at Parkland Memorial Hospital: A Quality Improvement Initiative With Novel Applications for Clinical Outcomes

Background: Focused cardiac ultrasound (FCU) has been used to answer clinical questions. Chemotherapy-related cardiotoxicity (CRR) is an entity that requires serial echocardiography. It is unknown whether FCU can be used to screen for CRR using advanced practice providers (APPs). The goal of this study is to determine if FCU can be used to reliably evaluate left ventricular ejection fraction (EF) by an APP to assess for CRR. Methods: The study was conducted at the Echo lab and the Oncology clinic. An Oncology APP was trained on the use of FCU and EF analysis. The APP was trained to obtained standard 2D views for EF assessment and on EF interpretation. The EF assessment was compared to sonographer echocardiogram on the same day. EF was assessed by a cardiologist and this was deemed to be the gold standard. The studies were all analyzed by two separate blinded cardiologists and the degree of correlation was analyzed. Linear regression modeling to analyze correlation between EF interpretation between all blinded observers and Bland Altman analysis was performed. Image quality was evaluated for all FCU images by a single blinded cardiologist and segmental endocardial border delineation was scored. Results: A total of 91 patients were scanned in Phase I of the study. The correlation coefficient between cardiologists was r=0.93. The correlation between cardiologist and APP were r=0.79 and 0.76 respectively. For the images obtained by the APP, the correlation between the APP and cardiologists were =0.83 and re=0.78. The correlation between APP and EF gold standard was r=0.77. The correlation between experienced cardiologists interpreting the FCU images was r=0.87. All images were determined to be interpretable. Conclusions: There was good correlation between cardiologists with respect to EF analysis. There was also good correlation between APP and cardiologists for EF analysis. Image quality from FCU was found to be good and acceptable for interpretation. This study demonstrates it is feasible to train an APP on obtaining images for EF analysis and they can be trained on EF interpretation with good correlation with experienced echocardiographers. We will evaluate outcomes associated with its use including delays to chemotherapy imposed by traditional echocardiography, cost to the health care system and patient-reported outcomes.

Impact of image quality on reliability of the measurements of left ventricular systolic function and global longitudinal strain in 2D echocardiography

Background: Left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) play important roles in diagnosis and management of cardiac diseases. However, the issue of the accuracy and reliability of LVEF and GLS remains to be solved. Image quality is one of the most important factors affecting measurement variability. The aim of this study was to investigate whether improved image quality could reduce observer variability.Methods: Two sets of three apical images were acquired using relatively old- and new-generation ultrasound imaging systems (Vivid 7 and Vivid E95) in 308 subjects. Image quality was assessed by endocardial border delineation index (EBDI) using a 3-point scoring system. Three observers measured the LVEF and GLS, and these values and inter-observer variability were investigated.Results: Image quality was significantly better with Vivid E95 (EBDI: 26.8 ± 5.9) than that with Vivid 7 (22.8 ± 6.3, P < 0.0001). Regarding the inter-observer variability of LVEF, the r-value, bias, 95% limit of agreement and intra-class correlation coefficient for Vivid 7 were comparable to those for Vivid E95. The % variabilities were significantly lower for Vivid E95 (5.3–6.5%) than those for Vivid 7 (6.5–7.5%). Regarding GLS, all observer variability parameters were better for Vivid E95 than for Vivid 7. Improvements in image quality yielded benefits to both LVEF and GLS measurement reliability. Multivariate analysis showed that image quality was indeed an important factor of observer variability in the measurement of LVEF and GLS.Conclusions: The new-generation ultrasound imaging system offers improved image quality and reduces inter-observer variability in the measurement of LVEF and GLS.

Echocardiographic Image Quality Deteriorates with Age in Children and Young Adults with Duchenne Muscular Dystrophy.

Advances in medical care for patients with Duchenne muscular dystrophy (DMD) have resulted in improved survival and an increased prevalence of cardiomyopathy. Serial echocardiographic surveillance is recommended to detect early cardiac dysfunction and initiate medical therapy. Clinical anecdote suggests that echocardiographic quality diminishes over time, impeding accurate assessment of left ventricular systolic function. Furthermore, evidence-based guidelines for the use of cardiac imaging in DMD, including cardiac magnetic resonance imaging (CMR), are limited. The objective of our single-center, retrospective study was to quantify the deterioration in echocardiographic image quality with increasing patient age and identify an age at which CMR should be considered. We retrospectively reviewed and graded the image quality of serial echocardiograms obtained in young patients with DMD. The quality of 16 left ventricular segments in two echocardiographic views was visually graded using a binary scoring system. An endocardial border delineation percentage (EBDP) score was calculated by dividing the number of segments with adequate endocardial delineation in each imaging window by the total number of segments present in that window and multiplying by 100. Linear regression analysis was performed to model the relationship between the EBDP scores and patient age. Fifty-five echocardiograms from 13 patients (mean age 11.6 years, range 3.6-19.9) were systematically reviewed. By 13 years of age, 50% of the echocardiograms were classified as suboptimal with ≥30% of segments inadequately visualized, and by 15 years of age, 78% of studies were suboptimal. Linear regression analysis revealed a negative correlation between patient age and EBDP score (r = -2.49, 95% confidence intervals -4.73, -0.25; p = 0.032), with the score decreasing by 2.5% for each 1 year increase in age. Echocardiographic image quality declines with increasing age in DMD. Alternate imaging modalities may play a role in cases of poor echocardiographic image quality.

Myocardial Contrast Agents – Safety Considerations and Clinical Efficacy in Stress Echocardiography

Abstract Transthoracic echocardiographic examination is known to be a safe, non-invasive and reproducible method, used in every day clinical practice to obtain important information about cardiac structure and function. Unfortunately, a significant proportion of studies have highlighted the considerable technically difficultly in producing diagnostic images due to a poor acoustic window and more than 33% of patients undergoing stress echocardiography have suboptimal echocardiographic images. All these limitations have led to the use of contrast agents to improve the quality of standard ultrasound examination to provide a better delineation of left ventricle endocardial borders or to obtain information that cannot be achieved by using standard echocardiography, such as assessing myocardial microcirculation and therefore perfusion. This paper sought to review the clinical efficacy and safety of ultrasound contrast agents focusing on stress echocardiography.

Utilization of diagnostic ultrasound and intravenous lipid-encapsulated perfluorocarbons in non-invasive targeted cardiovascular therapeutics.

Diagnostic ultrasound (DUS) pressures have the ability to induce inertial cavitation (IC) of systemically administered microbubbles; this bioeffect has many diagnostic and therapeutic implications in cardiovascular care. Diagnostically, commercially available lipid-encapsulated perfluorocarbons (LEP) can be utilized to improve endocardial and vascular border delineation as well as assess myocardial perfusion. Therapeutically, the liquid jets induced by IC can alter endothelial function and dissolve thrombi within the immediate vicinity of the cavitating microbubbles. The cavitating LEP can also result in the localized release of any bound therapeutic substance at the site of insonation. DUS-induced IC has been tested in pre-clinical studies to determine what effect it has on acute vascular and microvascular thrombosis as well as nitric oxide (NO) release. These pre-clinical studies have consistently shown that DUS-induced IC of LEP is effective in restoring coronary vascular and microvascular flow in acute ST segment elevation myocardial infarction (STEMI), with microvascular flow improving even if upstream large vessel flow has not been achieved. The initial clinical trials examining the efficacy of short pulse duration DUS high mechanical index impulses in patients with STEMI are underway, and preliminary studies have suggested that earlier epicardial vessel recanalization can be achieved prior to arriving in the cardiac catheterization laboratory. DUS high mechanical index impulses have also been effective in pre-clinical studies for targeting DNA delivery that has restored islet cell function in type I diabetes and restored vascular flow in the extremities downstream from a peripheral vascular occlusion. Improvements in this technique will come from three dimensional arrays for therapeutic applications, more automated delivery techniques that can be applied in the field, and use of submicron-sized acoustically activated LEP droplets that may better permeate the clot prior to DUS activation and cavitation. This article will focus on these newer developments for DUS therapeutic applications.Electronic supplementary materialThe online version of this article (doi:10.1186/s40349-016-0062-y) contains supplementary material, which is available to authorized users.