Echocardiography Imaging Research Articles

Current use of echocardiography in cardio-oncology: nationwide real-world data from an ANMCO/SIECVI joint survey.

The need for cardio-oncology competencies is constantly growing, and with the establishment of cardio-oncology services, cardiovascular imaging, particularly transthoracic echocardiography (TTE), has become pivotal in patients' management. However, care pathways for oncologic patients largely depend on local health structures' resources. This survey from Associazione Italiana Medici Cardiologi Ospedalieri and the Italian Society of Echocardiography and Cardiovascular Imaging aimed at investigating the use of echocardiography in cardio-oncology services and knowledge levels on cancer patients' care. Data were obtained via an electronic survey based on a structured questionnaire uploaded to the promoting societies' websites. Responses came from 159 centres with echocardiography. According to one-third of participating centres, workload related to cancer patients represented >30% of the total requests. The most common TTE indication (85%) was left ventricular ejection fraction (LVEF) evaluation. Many centres (55%) still assessed LVEF solely by bidimensional method or visual estimation in case of inadequate acoustic windows. At the same time, almost 40% of centres reported routinely using global longitudinal strain when feasible. We further performed a sub-analysis according to the presence (33%) or absence (77%) of dedicated cardio-oncologists, revealing significant differences in cardiovascular surveillance strategies and cardiotoxicity management. This survey on echocardiography practice for cancer patients reveals a significant gap between actual clinical practice and standards proposed by recommendations, underlying the need for stronger partnerships between cardiologists and oncologists and dedicated, well-structured cardio-oncology services.

Characterization of a novel SCN5A mutation associated with long QT syndrome and arrhythmogenic right ventricular cardiomyopathy in a family.

Sudden cardiac death represents a significant diagnostic challenge for forensic pathologists, particularly in inherited arrhythmia syndromes or cardiomyopathies resulting from genetic defects. Molecular autopsies can reveal the underlying molecular etiology in such cases. In this study, we investigated a family with a history of sudden cardiac death to elucidate the molecular basis responsible for sudden cardiac death. The proband underwent a comprehensive forensic examination. Family members received thorough clinical evaluations, including electrocardiogram, Holter monitoring, echocardiography, and cardiac magnetic imaging. Whole exome sequencing and genetic analysis were performed on the deceased and her parents. In addition, Western blotting and patch-clamp recordings were employed to evaluate the expression and function of the mutant protein in vitro. Forensic examination diagnosed arrhythmogenic right ventricular cardiomyopathy (ARVC) as the cause of sudden death. Genetic analysis identified a novel missense mutation in SCN5A (p.V1323L), which was assessed as likely pathogenic by the ACMG guideline. Another family member carrying the mutation manifested long QT syndrome and mild cardiac fibrosis. The cellular electrophysiological study demonstrated that the mutation resulted in an enhanced late sodium current, suggesting it was a gain-of-function mutation. This study characterizes a novel SCN5A mutation that putatively causes long QT syndrome and may contribute to the development of ARVC. Our work expands the pathogenic spectrum of SCN5A variants and underscores the importance of molecular autopsy in sudden death cases, especially in those with suspected genetic disorders.

Clinical implications of different methods to assess left atrial remodeling: A comparative study between echocardiography and cardiac magnetic resonance imaging for left atrial volume index quantification

BackgroundLeft atrial volume index (LAVI) serves as a crucial marker for assessing left atrial (LA) remodeling, particularly in patients with mitral valve regurgitation (MR). Recent guidelines recommend a LAVI exceeding 60 mL/m2 as Class IIa recommendation for mitral valve repair surgery in asymptomatic MR patients with preserved left ventricular function. Traditionally, echocardiography is the standard for assessing LAVI in MR patients. However, cardiac magnetic resonance imaging (CMR) is increasingly recognized for its more precise measurements of cardiac dimensions and volumes. But still, literature remains scarce on comparing the efficacy of both modalities in assessing LAVI measurements. MethodsThis retrospective study included 168 MR patients undergoing both echocardiography and CMR assessments within a six-month period. LAVI measurements were compared using Pearson correlation and Bland-Altman plots. Patients were stratified based on MR grades, and clinical implications were assessed. ResultsMean LAVI differed significantly between echocardiography and CMR (47.1 ± 20.8 mL/m2 versus 70 ± 20.3 mL/m2, p < 0.001, respectively). CMR consistently yielded higher LAVI measurements compared to echocardiography, with a mean difference of approximately 20 mL/m2. CMR measurements resulted in an increased incidence of patients meeting the class IIa LAVI criterion (LAVI >60 mL/m2) by 37%. Variations in LAVI did not differ across MR grades. ConclusionEchocardiography systematically underestimates LAVI compared to CMR in MR patients. While current guidelines rely on echocardiography, CMR's precision suggests the need for CMR-specific LAVI cutoff values to guide clinical management effectively. Establishing such values could refine patient stratification and timing of surgery, potentially improving clinical outcomes for MR patients.

Assessment of right ventricular systolic function using speckle tracking strain imaging in patients with severe tricuspid regurgitation: a validation study with cardiac magnetic resonance

BackgroundRight ventricular (RV) systolic dysfunction is an established prognostic factor in patients with severe tricuspid regurgitation (TR). However, accurate assessment of RV systolic function using conventional echocardiography remains challenging. We investigated the accuracy of strain measurement using speckle tracking echocardiography (STE) for evaluating RV systolic function in patients with severe TR.MethodsWe included consecutive patients with severe TR who underwent echocardiography and cardiac magnetic resonance imaging (CMR) within 30 days between 2011 and 2023. Two-dimensional STE was used to measure RV free wall longitudinal strain (RVFWLS) and global longitudinal strain (RVGLS). These values were compared with the RV ejection fraction (RVEF) from CMR. RV systolic dysfunction was defined as a CMR-derived RVEF < 35%.ResultsA total of 87 patients with severe TR were identified during the study period. Among echocardiographic RV strain measurements, RVFWLS was the best correlate of CMR-derived RVEF (r = –0.37, P < 0.001), followed by RVGLS (r = –0.27, P = 0.012). Receiver operating characteristic (ROC) curve analysis revealed that RVFWLS provided better discrimination of RV systolic dysfunction, yielding an area under the ROC curve (AUC) of 0.770 (95% confidence interval [CI], 0.696–0.800) than RV fractional area change (AUC, 0.615; 95% CI, 0.500–0.859).ConclusionsIn patients with severe TR, STE-derived RVFWLS showed the best correlation with RVEF on CMR and displayed superior discrimination of RV systolic dysfunction compared with the RV fractional area change. This study suggests the potential usefulness of STE in assessing RV systolic function in this population.

Chronic Right Ventricular Pacing Post-Transcatheter Aortic Valve Replacement Attenuates the Benefit on Left Ventricular Function.

Background: Conduction abnormality post-transcatheter aortic valve implantation (TAVI) remains clinically significant and usually requires chronic pacing. The effect of right ventricular (RV) pacing post-TAVI on clinical outcomes warrants further studies. Methods: We identified 147 consecutive patients who required chronic RV pacing after a successful TAVI procedure and propensity-matched these patients according to the Society of Thoracic Surgeons (STS) risk score to a control group of patients that did not require RV pacing post-TAVI. We evaluated routine echocardiographic measurements and performed offline speckle-tracking strain analysis for the purpose of this study on transthoracic echocardiographic (TTE) images performed at 9 to 18 months post-TAVI. Results: The final study population comprised 294 patients (pacing group n = 147 and non-pacing group n = 147), with a mean age of 81 ± 7 years, 59% male; median follow-up was 354 days. There were more baseline conduction abnormalities in the pacing group compared to the non-pacing group (56.5% vs. 41.5%. p = 0.01). Eighty-eight patients (61.6%) in the pacing group required RV pacing due to atrioventricular (AV) conduction block post-TAVI. The mean RV pacing burden was 44% in the pacing group. Left ventricular ejection fraction (LVEF) was similar at follow-up in the pacing vs. non-pacing groups (57 ± 13.0%, 59 ± 11% p = 0.31); however, LV global longitudinal strain (-12.7 ± 3.5% vs. -18.8 ± 2.7%, p < 0.0001), LV apical strain (-12.9 ± 5.5% vs. 23.2 ± 9.2%, p < 0.0001), and mid-LV strain (-12.7 ± 4.6% vs. -18.7 ± 3.4%, p < 0.0001) were significantly worse in the pacing vs. non-pacing groups. Conclusions: Chronic RV pacing after the TAVI procedure is associated with subclinical LV systolic dysfunction within 1.5 years of follow-up.

Integrating myocardial metabolic imaging and stress myocardial contrast echocardiography to improve the diagnosis of coronary microvascular diseases in rabbits.

Persistent challenges associated with misdiagnosis and underdiagnosis of coronary microvascular disease (CMVD) necessitate the exploration of noninvasive imaging techniques to enhance diagnostic accuracy. Therefore, we aimed to integrate multimodal imaging approaches to achieve a higher diagnostic rate for CMVD using high-quality myocardial metabolism imaging (MMI) and myocardial contrast echocardiography (MCE). This combination diagnostic strategy may help address the urgent need for improved CMVD diagnosis. In this study, we established five distinct pretreatment groups, each consisting of nine male rabbit: a fasted group, a nonfasted group, a sugar load group, an acipimox group, and a combination group of nonfasted rabbits administered insulin. Moreover, positron emission tomography-computed tomography (PET/CT) scan windows were established at 30-, 60-, and 90-minute intervals. We developed 10 CMVD models and conducted a diagnosis of CMVD through an integrated analysis of MMI and MCE, including image acquisition and processing. For each heart segment, we calculated the standardized uptake value (SUV) based on body weight (SUVbw), as well as certain ratios of SUV including SUV of the heart (SUVheart) to that of the liver (SUVliver) and SUVheart to SUV of the lung (SUVlung). Additionally, we obtained three coronary SUVbw uptake values. To clarify the relationship between SUVbw uptake values and echocardiographic parameters of the myocardial contrast agent more thoroughly, we conducted a comprehensive analysis across different pretreatment protocols. Receiver operating characteristic (ROC) curve analysis was employed to evaluate the diagnostic accuracy of each parameter in the context of CMVD. In the context of MMI, the nonfasted-plus-insulin group, as observed during the 60-minute examination, exhibited a noteworthy total 18F-fluorodeoxyglucose (18F-FDG) uptake of 47.44±6.53 g/mL, which was found to be statistically different from the other groups. To ascertain the reliability of the results, two double-blind investigators independently assessed the data and achieved a good level of agreement, according to the intraclass correlation coefficient (ICC) (0.957). The SUVbw of the nonfasted-plus-insulin group exhibited a moderate correlation with the microvascular blood flow reserve (MBFR) parameters derived from the MCE examination, as evidenced by a r value of 0.686. For the diagnosis of CMVD disease, the diagnostic accuracy of the combined diagnostic method [area under the curve (AUC) =0.789; 95% confidence interval (CI): 0.705-0.873] was significantly higher than that of the MBFR (AUC =0.697; 95% CI: 0.597-0.797) and SUVbw (AUC =0.715; 95% CI: 0.622-0.807) methods (P<0.05). Our study demonstrated the feasibility of a simple premedication approach involving free feeding and intravenous insulin in producing high-quality gated heart 18F-FDG PET/CT images in adult male New Zealand white rabbits. This technique holds considerable potential for ischemic heart disease research in rabbits and can enhance CMVD diagnosis via the comprehensive assessment of myocardial metabolism and perfusion.

A Characterization of the Cardiac Physiology and Aortic Pulse Wave Properties of Artistic Swimmers Across Competitive Levels.

The distinct physical and environmental stressors of artistic swimming (previously termed synchronized swimming) result in unique hemodynamic stimuli. Given that the hemodynamic stress associated with participation in an exercise modality drives adaptation of the heart and central vasculature, artistic swimming may produce a distinct cardiovascular phenotype. Presumably, athletes competing at the highest levels also have greater training exposure and, thus, exhibit more adaptation. The purpose of this study was to characterize cardiovascular form and function across the competitive spectrum of artistic swimmers. Cardiovascular structure and function were compared in a cross-sectional study of healthy controls, varsity, and elite artistic swimmers, using pulse wave analysis, pulse wave velocity, and echocardiographic images both at rest and during isometric handgrip exercise. Aortic stiffness was similar across all groups, as were characteristics of the decomposed aortic pressure waveform. At rest, both varsity and elite swimmers demonstrated similar systolic function compared to controls. However, peak left ventricular twist was greater in varsity and elites (controls: 8.0 ± 3.9, varsity: 12.8 ± 8.6, elites: 13.4 ± 3.9; both p < 0.02). Furthermore, elites demonstrated greater peak left ventricular radial strain (controls: 29.2 ± 9.9, varsity: 32.5 ± 10.3, elites: 53.9 ± 15.1; both p < 0.001) and longitudinal strain (controls: -16.9 ± 1.6, varsity: -16.5 ± 1.8, elites: -19.5 ± 3.2; both p < 0.04). In contrast to controls, both varsity and elite artistic swimmers demonstrated no change in peak late diastolic transmitral filling velocity (controls: Δ0.2 ± 0.04 m/s, varsity: Δ0.06 ± 0.04 m/s, elites: Δ0.05 ± 0.04 m/s) during isometric handgrip exercise (both p > 0.05), with elites demonstrating lower peak velocity than varsity swimmers, (p = 0.048) indicating preservation of diastolic function. Artistic swimmers demonstrate distinct cardiac physiology at rest and during isometric handgrip, with a greater extent of distinguishing features observed in those competing at the highest level of competition.

The Loop Technique in Cardiac Resynchronization Therapy: A Prospective Cohort Study.

A new approach called the loop technique has been proven safe and effective for repeated intraoperative transvenous left ventricular (LV) lead dislocations during cardiac resynchronization therapy (CRT) in a 3-year follow-up. This study aimed to report on the 5-year safety and effectiveness of the loop technique. This study was a prospective cohort study. Forty-four patients who underwent CRT device implantation at the Cardiology Department of Shaanxi Provincial People's Hospital between January 2013 and June 2019 were included. Data on patient demographics, medical history, laboratory test results, and echocardiography images at admission were collected. The loop technique was performed with repeated intraoperative dislocations of the LV lead. The intraoperative CRT parameters were also recorded. All patients were followed for 5 years. Several auxiliary examinations were performed during follow-up. The 44 patients were divided into the traditional operation group (n=36, 81.8%) and loop technique group (n=8, 18.2%). The baseline patient characteristics were almost balanced. During the 5-year follow-up, 8 (22.2%) patients in the traditional operation group and 2 (25.0%) patients in the loop technique group died. No lead dislocation or other complications related to CRT were observed. There were no significant differences in mortality rate (P=0.87), cardiac function (P=0.56), echocardiographic indices, threshold (P=0.58), or impedance (P=0.22) of the LV lead. There were no significant differences in the threshold and impedance between postoperative, 3-year, and 5-year follow-ups in the loop technique group (P=0.53). The loop technique is an ideal solution for repeated intraoperative LV lead dislocation during CRT implantation.

Feasibility, reproducibility, and accuracy of echocardiographic right ventricular systolic function assessments in childhood cancer survivors at risk for heart failure.

We sought to assess the feasibility, reproducibility, and accuracy of conventional and newer echocardiographic measures of right ventricular (RV) systolic function in adolescent and young adult childhood cancer survivors treated with anthracyclines. Echocardiography and cardiac magnetic resonance imaging (CMR) were acquired ≤60 days apart in prospectively recruited survivors and RV functional measures were quantitated by blinded observers. Repeat quantitation was performed in a subset to evaluate reproducibility. For each echocardiographic measure, Spearman correlations with CMR measures were calculated, and values in participants with CMR RV ejection fraction (RVEF) ≥48% and RVEF <48% were compared using two sample Wilcoxon rank-sum tests. Among 58 participants, mean age was 18.2 years (range 13.1-25.2) and five participants had CMR RVEF <48%. Intra- and inter-observer coefficients of variation were 8.2%-10.1% and 10.5%-12.0% for adjusted automated strain measures, and 5.2%-8.7% and 2.7% for 3D RVEF, respectively. No echocardiographic measures were significantly correlated with CMR RVEF; only tricuspid annular plane systolic excursion was correlated with CMR RV stroke volume (r=.392, p=.003). Participants with RV dysfunction had worse automated global longitudinal strain (-20.3% vs. -23.9%, p=.007) and free wall longitudinal strain (-23.7% vs. -26.7%, p=.09). Echocardiographic strain and 3D RV function measurements were feasible and reproducible in at-risk childhood cancer survivors. Although not associated with CMR RVEF in this population with predominantly normal RV function, automated strain measurements were more abnormal in participants with RV dysfunction, suggesting potential clinical utility of these measures.

Left bundle branch area pacing guided by intracardiac echocardiography imaging

Left bundle branch area pacing guided by intracardiac echocardiography imaging

Echocardiographic evaluation in koi carp (Cyprinus carpio) under manual restraint compared to anesthesia with isoeugenol.

To establish an echocardiographic technique in koi carp (Cyprinus carpio), compare cardiopulmonary parameters under manual restraint versus anesthesia, and provide a gross anatomical and histologic cardiac description. A randomized, crossover echocardiography study was performed in 40 clinically healthy adult, unknown sex, privately owned koi carp on May 10 and 11 through June 26 and 27, 2021. Echocardiography was examined for each koi under manual restraint and isoeugenol at 50 ppm, with 3 measurements per examination performed by a radiologist and cardiologist. Two koi were euthanized for gross anatomic and histologic cardiac evaluation. Mean ejection fraction (EF), stroke volume (SV), and cardiac output (CO) were significantly lower, mean heart rate (HR) was significantly higher, and opercular rate (OPR) was decreased significantly in anesthetized compared to manually restrained koi. Poor reproducibility for EF and SV was observed. Echocardiography was feasible in both manually restrained and anesthetized koi; however, this technique may best be applied to monitoring trends over time in individual fish due to low reproducibility. Significant differences in multiple cardiopulmonary parameters, including HR, EF, SV, CO, and OPR, were present between manually restrained and anesthetized koi. A gross anatomic and histologic cardiac description is provided for this species to pair with the echocardiographic images. This study provides the first description of echocardiography, cardiac gross anatomy, and histology in koi. The results support echocardiography as a safe and practical noninvasive diagnostic for cardiac assessment in koi under both manual restraint and anesthesia.

Echocardiographic imaging and anatomic characteristics of true univentricular heart manifesting as double inlet - double outlet right ventricle: Case report and literature review

Echocardiographic imaging and anatomic characteristics of true univentricular heart manifesting as double inlet - double outlet right ventricle: Case report and literature review

Clinical Diagnostic Workflow of Nondilated Left Ventricular Cardiomyopathy: A Case-based Review

Abstract Dilated cardiomyopathy is defined as left ventricular (LV) or biventricular dysfunction and dilatation not explained by abnormal loading conditions or coronary artery disease. However, the existing definition does not cover a range of disorders that manifest as a spectrum of electrical, structural, and functional myocardial abnormalities that change over time. With the rising use of echocardiographic speckle tracking strain imaging and cardiac magnetic resonance imaging, subtle myocardial structural or functional pathology can be detected very early in the natural history of the myocardial disease. The 2023 European Society of Cardiology guidelines for cardiomyopathy have coined a new terminology “nondilated LV cardiomyopathy (NDLVC)” to help in early risk stratification and better patient surveillance and therapeutic management. This article is a case series of NDLVC with an emphasis on systematic clinical workup for early diagnosis and better management of this pathology.

Effect of Hypertension on the Left Atrium Using Tissue Doppler Imaging Echocardiography

Effect of Hypertension on the Left Atrium Using Tissue Doppler Imaging Echocardiography

Biomarcadores proteómicos para la predicción no invasiva de trombos en la orejuela izquierda de pacientes con fibrilación auricular

Introduction and objectivesThe CHA2DS2-VASc score, used to assess the risk of left atrial appendage thrombus (LAAT) formation in patients with atrial fibrillation (AF), has limited predictive value. Moreover, transesophageal echocardiography imaging, the gold standard diagnostic method to identify thrombi, is semi-invasive. Consequently, there is a need for alternative and noninvasive diagnostic methods for LAAT risk assessment. MethodsDeep proteomic analysis was conducted in plasma samples from 8 patients with nonvalvular AF, divided into thrombus and control groups (4 patients in each group) based on the presence or absence of LAAT. Biomarkers associated with LAAT were validated using an enzyme-linked immunosorbent assay in a cohort of 179 patients with available clinical, transthoracic, and transesophageal echocardiography data. Predictive models were developed to assess the improvement in LAAT identification. ResultsThe LAAT group had higher CHA2DS2-VASc scores, larger LA diameter, and lower LAA flow velocities. Deep proteomic analysis identified 30 differentially expressed proteins, including myosin light chain 4, prenylcysteine oxidase 1 (PCYOX1), and decorin as potential diagnostic biomarkers of LAAT. The model showed that PCYOX1 and decorin provided an area under the curve (AUC) of 0.970 for LAAT prediction compared with 0.672 in a model including the CHA2DS2-VASc score and LAA cauliflower morphology. The incremental value of proteomic biomarkers for LAAT in patients with nonvalvular AF was further confirmed with the net reclassification improvement and integrated discrimination improvement indices. ConclusionsProtein levels of PCYOX1 and decorin improve the predictive performance for LAAT in patients with nonvalvular AF.

Myocardial work and risk stratification in patients with severe aortic valve stenosis referred for transcatheter aortic valve replacement

BackgroundTranscatheter aortic valve replacement(TAVR) has shown clear survival benefits in severe aortic valve stenosis(AS). However, patients unable to recover left ventricle function remain at risk with poor long-term survival. This single-center prospective study aims to analyze the supplementary benefits of myocardial work(MW) assessment for baseline risk stratification in patients with severe AS referred for TAVR. MethodsA total of 110 patients with severe AS referred for TAVR were included in the study. Baseline ECG data, transthoracic echocardiographic(TTE) images and blood samples were obtained. The TTE examination was repeated one day and one month after valve replacement. The primary outcome of the study was a composite endpoint consisting of all-cause mortality and HF hospitalization. ResultsDuring a mean follow-up period of 521 ± 343 days, 29patients(26.4 %) reached the composite endpoint. Baseline troponins, NT-proBNP, sST2, GWI and GCW showed statistically significant differences between groups. Patients with a baseline GWI<2323 mmHg% (sensitivity 0.63 and specificity 0.76)had significantly worse outcome following TAVR. A basic predictive model included QRS-length, TAPSE, LAVI and E/e’. The addition of biomarkers did not yield any further advantages whereas incorporating the GWI cut-off value of 2323 mmHg% significantly enhanced the predictive value. Although there were no significant changes in LVEF and GLS, all patients exhibited a significant reduction in GWI and GCW immediately after TAVR. ConclusionOur findings provide evidence for the enhanced usefulness of MW analysis in the initial risk stratification of patients with severe AS referred for TAVR. Specifically, a baseline GWI<2323 mmHg% demonstrates an independent predictor associated with increased incidence of all-cause mortality and HF hospitalization following TAVR.

Artificial intelligence-derived left ventricular strain in echocardiography in patients treated with chemotherapy

Global longitudinal strain (GLS) is an echocardiographic measure to detect chemotherapy-related cardiovascular dysfunction. However, its limited availability and the needed expertise may restrict its generalization. Artificial intelligence (AI)-based GLS might overcome these challenges. Our aims are to explore the agreements between AI-based GLS and conventional GLS, and to assess whether the agreements were influenced by expertise levels, cardiac remodeling and cardiovascular diseases/risks. Echocardiographic images in the apical four-chamber view of left ventricle were retrospectively analyzed based on AI-based GLS in patients treated with chemotherapy, and correlation between AI-based GLS (Caas Qardia, Pie Medical Imaging) and conventional GLS (Vivid E9/VividE95, GE Healthcare) were assessed. The agreement between unexperienced physicians (“GLS beginner”) and experienced echocardiographer were also assessed. Among 94 patients (mean age 69 ± 12 years, 73% female), mean left ventricular ejection fraction was 64 ± 6%, 14% of patients had left ventricular hypertrophy, and 21% had left atrial enlargement. Mean GLS was − 15.9 ± 3.4% and − 19.0 ± 3.7% for the AI and conventional method, respectively. There was a moderate correlation between these methods (rho = 0.74; p < 0.01), and bias was − 3.1% (95% limits of agreement: -8.1 to 2.0). The reproducibility between GLS beginner and an experienced echocardiographer was numerically better in the AI method than the conventional method (inter-observer agreement = 0.82 vs. 0.68). The agreements were consistent across abnormal cardiac structure and function categories (p-for-interaction > 0.10). In patients treated with chemotherapy. AI-based GLS was moderately correlated with conventional GLS and provided a numerically better reproducibility compared with conventional GLS, regardless of different levels of expertise.

Comparison of Left Ventricular Function Derived from Subject-Specific Inverse Finite Element Modeling Based on 3D ECHO and Magnetic Resonance Images.

Three-dimensional echocardiography (3D ECHO) and magnetic resonance (MR) imaging are frequently used in patients and animals to evaluate heart functions. Inverse finite element (FE) modeling is increasingly applied to MR images to quantify left ventricular (LV) function and estimate myocardial contractility and other cardiac biomarkers. It remains unclear, however, as to whether myocardial contractility derived from the inverse FE model based on 3D ECHO images is comparable to that derived from MR images. To address this issue, we developed a subject-specific inverse FE model based on 3D ECHO and MR images acquired from seven healthy swine models to investigate if there are differences in myocardial contractility and LV geometrical features derived using these two imaging modalities. We showed that end-systolic and end-diastolic volumes derived from 3D ECHO images are comparable to those derived from MR images (R2=0.805 and 0.969, respectively). As a result, ejection fraction from 3D ECHO and MR images are linearly correlated (R2=0.977) with the limit of agreement (LOA) ranging from -17.95% to 45.89%. Using an inverse FE modeling to fit pressure and volume waveforms in subject-specific LV geometry reconstructed from 3D ECHO and MR images, we found that myocardial contractility derived from these two imaging modalities are linearly correlated with an R2 value of 0.989, a gradient of 0.895, and LOA ranging from -6.11% to 36.66%. This finding supports using 3D ECHO images in image-based inverse FE modeling to estimate myocardial contractility.

Contrast efficacy of novel phase convertible nanodroplets for safe CEUS imaging

Microbubble contrast agents in ultrasound/echocardiography are used to increase the echogenicity of the target tissues, thereby raising the contrast resolution of the resultant image. Recently, the trend has shifted toward the development of phase-convertible nanodroplets as ultrasound contrast agents due to their promising theragnostic potential by switching capability at the active site. Herein, we fabricated pre-PGS- perfluoropentane phase convertible nanodroplets and checked their in vitro and in vivo enhancement and safety profile. For this, we performed experiments on 20 male Wistar rats and 2 dogs. Biochemical assays of both rats and dogs included complete blood profiles, liver function tests, and renal function tests. For rat vitals, monitoring and histopathological analysis were also performed. Converted nanodroplets showed excellent contrast enhancement, better than Sonovue upon in vitro testing, with an enhancement time of up to 14 min. In vivo, experiments showed comparable opacification of the ventricles of both rats and dogs. All biochemical assays remained within the normal range during the study period. The histopathological analysis did not show any signs of drug-induced toxicity, showing the safety of these nanodroplets. Pre-PGS-PFP nanodroplets hold great potential for use in echocardiography and abdominal imaging in both human and veterinary applications after clinical trials.

Automated Quality Assessment of Medical Images in Echocardiography Using Neural Networks with Adaptive Ranking and Structure-Aware Learning.

The quality of medical images is crucial for accurately diagnosing and treating various diseases. However, current automated methods for assessing image quality are based on neural networks, which often focus solely on pixel distortion and overlook the significance of complex structures within the images. This study introduces a novel neural network model designed explicitly for automated image quality assessment that addresses pixel and semantic distortion. The model introduces an adaptive ranking mechanism enhanced with contrast sensitivity weighting to refine the detection of minor variances in similar images for pixel distortion assessment. More significantly, the model integrates a structure-aware learning module employing graph neural networks. This module is adept at deciphering the intricate relationships between an image's semantic structure and quality. When evaluated on two ultrasound imaging datasets, the proposed method outshines existing leading models in performance. Additionally, it boasts seamless integration into clinical workflows, enabling real-time image quality assessment, crucial for precise disease diagnosis and treatment.