Right Ventricular Thrombus on Echocardiography.

Right ventricular thrombi (RVTs) have been almost exclusively studied in patients with pulmonary embolism (PE). The implications of an isolated RVT, a finding typically encountered on transthoracic echocardiography (TTE), are lacking. In this study, we sought to identify the echocardiographic and clinical features associated with the presence of RVTs. Between 1998 and 2023, 138 patients with RVT documented on TTE were retrospectively identified. Demographic data, presence of intracardiac devices, hypercoagulable conditions, history of deep vein thrombosis (DVT), PE, and/or left ventricular thrombus were abstracted from electronic chart review. Measurements of right and left ventricular size, and function were performed on TTE. Of the total population of patients with RVT, <1/2 had intracardiac devices, 29% had a documented hypercoagulable state (e.g., cancer or a clotting disorder). Most patients had dilated (77%) and dysfunctional (72%) right ventricles. Approximately 50% of RVTs were discovered in nonstandard imaging planes, suggesting that the presence of RVT is likely underestimated in clinical practice. Of those evaluated for PE, 80% had PE. Of those evaluated for DVT, 53% had DVT. In conclusion, further investigations are warranted to better guide when to investigate the right ventricle for RVTs on TTE and the impact of RVTs on patient outcomes.

Anomalous right coronary artery from the main pulmonary artery (ARCAPA): Incidental finding in an asymptomatic septuagenarian.

Anomalous right coronary artery (RCA) from the main pulmonary artery (ARCAPA) is a rare finding. Clinical presentations range from asymptomatic to sudden death. We present the case of ARCAPA in a septuagenarian initially suspected on a screening chest computed tomography (CT) and later confirmed on cardiac CT. A summary of important points related to this entity is also discussed.

How Often Does Apical Sparing of Longitudinal Strain Indicate the Presence of Cardiac Amyloidosis?

Echocardiographic diagnosis of cardiac amyloidosis (CA) is frequently suggested by the presence of a left ventricular (LV) apical sparing pattern (ASP) on longitudinal strain (LS) assessment, the so-called "cherry on top" pattern, defined by strain magnitude preserved exclusively at the apex. However, it is unclear how frequently this strain pattern truly represents CA. This study aimed to evaluate the predictive value of ASP in the diagnosis of CA. We retrospectively identified consecutive adult patients who had the following studies performed within an 18-month period: (1) transthoracic echocardiogram and (2) either (a) cardiac magnetic resonance imaging, (b) Technetium-Pyrophosphate (PYP) imaging, or (c) endomyocardial biopsy. LS was retrospectively measured in the apical 4-, 3-, and 2-chamber views in patients who had adequate noncontrast images (n = 466). An apical sparing ratio (ASR) was calculated as (average apical strain)/[(average basal strain) + (average midventricular strain)]. Patients with ASR ≥1 were evaluated for the presence/absence of CA, using established criteria. Basic LV parameters were also measured. A total of 33 patients (7.1%) had ASP. Nine of these patients (27%) had "confirmed" CA, 2 (6.1%) "highly probable" CA, 1 (3.0%) "possible" CA, and 21 (64%) no evidence of CA. When comparing patients with and without confirmed CA, there were no significant differences in ASR, average global LS, ejection fraction, or LV mass. Patients with confirmed CA were older (76 ± 9 vs 59 ± 18 years, p = 0.01) and had thicker posterior wall (15 ± 3 vs 11 ± 3 mm, p = 0.004) with a trend toward thicker septal wall (15 ± 2 vs 12 ± 4 mm, p = 0.05). In conclusion, the presence of ASP on LS represents confirmed or highly probable CA in only 1/3 of patients and is more likely to indicate true CA in older patients with increased LV wall thickness. Although a larger, prospective study is needed to confirm these findings, 1/3 should be considered as a large diagnostic yield that justifies further testing, given the poor outcomes associated with CA diagnosis.

Real-Time Artificial Intelligence-Based Guidance of Echocardiographic Imaging by Novices: Image Quality and Suitability for Diagnostic Interpretation and Quantitative Analysis.

BACKGROUND: We aimed to assess in a prospective multicenter study the quality of echocardiographic exams performed by inexperienced users guided by a new artificial intelligence software and evaluate their suitability for diagnostic interpretation of basic cardiac pathology and quantitative analysis of cardiac chamber and function. METHODS: The software (UltraSight, Ltd) was embedded into a handheld imaging device (Lumify; Philips). Six nurses and 3 medical residents, who underwent minimal training, scanned 240 patients (61±16 years; 63% with cardiac pathology) in 10 standard views. All patients were also scanned by expert sonographers using the same device without artificial intelligence guidance. Studies were reviewed by 5 certified echocardiographers blinded to the imager's identity, who evaluated the ability to assess left and right ventricular size and function, pericardial effusion, valve morphology, and left atrial and inferior vena cava sizes. Finally, apical 4-chamber images of adequate quality, acquired by novices and sonographers in 100 patients, were analyzed to measure left ventricular volumes, ejection fraction, and global longitudinal strain by an expert reader using conventional methodology. Measurements were compared between novices' and experts' images. RESULTS: Of the 240 studies acquired by novices, 99.2%, 99.6%, 92.9%, and 100% had sufficient quality to assess left ventricular size and function, right ventricular size, and pericardial effusion, respectively. Valve morphology, right ventricular function, and left atrial and inferior vena cava size were visualized in 67% to 98% exams. Images obtained by novices and sonographers yielded concordant diagnostic interpretation in 83% to 96% studies. Quantitative analysis was feasible in 83% images acquired by novices and resulted in high correlations (r≥0.74) and small biases, compared with those obtained by sonographers. CONCLUSIONS: After minimal training with the real-time guidance software, novice users can acquire images of diagnostic quality approaching that of expert sonographers in most patients. This technology may increase adoption and improve accuracy of point-of-care cardiac ultrasound.

Feasibility of Left Ventricular Global Longitudinal Strain Measurements from Contrast-Enhanced Echocardiographic Images.

BACKGROUND: Although left ventricular global longitudinal strain (GLS) is an index of systolic function recommended by the guidelines, poor image quality may hamper strain measurements. While contrast agents are commonly used to improve endocardial visualization, no commercial speckle-tracking software is able to measure strain in contrast-enhanced images. This study aimed to test the accuracy of speckle-tracking software when applied to contrast-enhanced images in patients with suboptimal image quality. METHODS: We studied patients with a wide range of GLS values who underwent transthoracic echocardiography. Protocol 1 included 44 patients whose images justified use of contrast but still allowed noncontrast speckle-tracking echocardiography (STE), which was judged as accurate and used as a reference. Protocol 2 included 20 patients with poor image quality that precluded noncontrast STE; cardiac magnetic resonance- (CMR-) derived strain was used as the reference instead. Half the manufacturer recommended dose of a commercial contrast agent (Definity/Optison/Lumason) was used to provide partial contrast enhancement. Higher than normal mechanical indices (0.6-0.7) and lowest frequency range for maximal penetration settings were used for imaging. GLS was measured (Epsilon) with and without contrast-enhanced images and by CMR-derived feature tracking (TomTec). Comparisons included linear regression and Bland-Altman analyses. RESULTS: The contrast STE analysis failed in 4/64 patients (6%). Manual corrections were needed to optimize tracking with contrast in all patients. GLS measurements were in good agreement between contrast and noncontrast images (r = 0.85; mean GLS in the contrast images, -12.9% ± 4.7%; bias, 0.34% ± 2.4%). Good agreement was also noted between contrast STE- and CMR-derived strain (r = 0.83; mean, GLS -13.5% ± 4.0%; bias, 0.72% ± 2.5%). CONCLUSIONS: We found that GLS measurements from contrast-enhanced images are feasible and accurate in most patients, even in those with poor image quality that precludes strain measurements without contrast enhancement.

Atrial-focused views improve the accuracy of two-dimensional echocardiographic measurements of the left and right atrial volumes: a contribution to the increase in normal values in the guidelines update.

Current guidelines recommend that the atria be measured in 2D echocardiographic (2DE) apical views using the method-of-disks (MOD) or area-length (AL) technique as an alternative, although no definitive data exists that these are interchangeable. However, standard apical views maximize the long-axis of the left ventricle, rather than the dimensions of the atria, resulting in atrial foreshortening. We hypothesized that the increase in normal values of atrial volumes in the recent guidelines update was driven by data obtained using either the AL technique or dedicated atrial-focused views, which maximize the longitudinal dimension of the atria and thus provide larger volumes than the MOD measurements in standard apical views. We prospectively studied 30 patients (Philips iE33) to compare 2DE measurements of left and right atrial volumes (LAV, RAV) using the MOD and AL techniques in standard and atrial-focused views, against 3D echocardiography (3DE) derived volumes (QLab) as a reference. Compared to standard views, atrial-focused views provided significantly larger MOD volumes for both atria, which were in better agreement with 3DE, as reflected by higher correlation coefficients (LAV: r = 0.95 vs. 0.89; RAV: r = 0.89 vs. 0.84), smaller biases (LAV: -1 ml vs. 7 ml; RAV: 3 ml vs. 7 ml) and tighter limits of agreement. This was also the case for the AL measurements, which were minimally larger than the MOD values (NS) for both atria. In conclusion, atrial-focused views are a more accurate alternative to standard apical views, which provides larger volumes. This finding can explain the increase in the normal values in the recent guidelines update, which was mostly driven by the use of atrial-focused views, rather than by the differences between MOD and AL techniques. This understanding is essential in order to correctly integrate the revised normal values into clinical practice.

Quantification of Right Ventricular Size and Function from Contrast-Enhanced Three-Dimensional Echocardiographic Images.

BACKGROUND: Three-dimensional (3D) echocardiography directly assesses right ventricular (RV) volumes without geometric assumptions, despite the complex shape of the right ventricle, and accordingly is more accurate and reproducible than the two-dimensional methodology, which is able to measure only surrogate parameters of RV function. Volumetric analysis has been hampered by frequent inability to clearly visualize RV endocardium, especially the RV free wall, in 3D echocardiographic images. The aim of this study was to test the hypothesis that RV contrast enhancement during 3D echocardiographic imaging would improve the accuracy of RV volume and function analysis. METHODS: Thirty patients with a wide range of RV size and function and image quality underwent transthoracic 3D echocardiography with and without contrast enhancement and cardiovascular magnetic resonance imaging on the same day. RV end-diastolic and end-systolic volumes and ejection fraction were measured from contrast-enhanced and nonenhanced 3D echocardiographic images and compared with cardiovascular magnetic resonance reference values using linear regression and Bland-Altman analyses. Blinded repeated measurements were performed to assess measurement variability. RESULTS: RV contrast enhancement was feasible in all patients. RV volumes obtained both with and without contrast enhancement correlated highly with cardiovascular magnetic resonance (end-diastolic volume, r = 0.90 and r = 0.92; end-systolic volume, r = 0.92 and r = 0.94, respectively), but the correlation for ejection fraction was better with contrast (r = 0.87 vs r = 0.70). Biases were smaller with contrast for all three parameters (end-diastolic volume, -16 ± 23 vs -36 ± 25 mL; end-systolic volume, -10 ± 16 vs -23 ± 18 mL; ejection fraction, -0.7 ± 5.5% vs -2.7 ± 8.1% of the mean measured values), reflecting improved accuracy. Also, measurement reproducibility was improved by contrast enhancement. CONCLUSIONS: Contrast enhancement improves the visualization of RV endocardial borders, resulting in more accurate and reproducible 3D echocardiographic measurements of RV size and function. This approach may be particularly useful in patients with suboptimal image quality.