Challenges and opportunities for early career medical professionals in cardiovascular magnetic resonance (CMR) imaging: a white paper from the Society for Cardiovascular Magnetic Resonance.

The early career professionals in the field of Cardiovascular Magnetic Resonance (CMR) face unique challenges and hurdles while establishing their careers in the field. The Society for Cardiovascular Magnetic Resonance (SCMR) has expanded the role of the early career section within the society to foster the careers of future CMR leaders. This paper aims to describe the obstacles and available opportunities for the early career CMR professionals worldwide. Societal opportunities and actions targeted at the professional advancement of the early career CMR imagers are needed to ensure continuous growth of CMR as an imaging modality globally.

Assessment of Right Ventricle Function and Tricuspid Regurgitation in Heart Failure: Current Advances in Diagnosis and Imaging.

Right ventricular (RV) systolic dysfunction increases mortality among heart failure patients, and therefore, accurate diagnosis and monitoring is paramount. RV anatomy and function are complex, usually requiring a combination of imaging modalities to completely quantitate volumes and function. Tricuspid regurgitation usually occurs with RV dysfunction, and quantifying this valvular lesion also may require multiple imaging modalities. Echocardiography is the first-line imaging tool for identifying RV dysfunction, with cardiac MRI and cardiac computed tomography adding valuable additional information.

Secondary Mitral Regurgitation and Heart Failure: Current Advances in Diagnosis and Management.

The causes of mitral regurgitation (MR) can be broadly divided into primary and secondary causes. Although primary MR is caused by degenerative alterations of the mitral valve and the mitral valve apparatus, secondary (functional) MR is multifactorial and related to dilation of the left ventricle and/or mitral annulus commonly resulting in concomitant restriction of the leaflets. Therefore, the treatment of secondary MR (SMR) is complex and includes guideline directed heart failure therapy along with surgical and transcatheter approaches that have shown effectiveness in certain subgroups. This review aims to provide insight into current advances in diagnosis and management of SMR.

The Emerging Role of Artificial Intelligence in Valvular Heart Disease.

Valvular heart disease (VHD) is a morbid condition in which timely identification and evidence-based treatments can lead to improved outcomes. Artificial intelligence broadly refers to the ability for computers to perform tasks and problem solve like the human mind. Studies applying AI to VHD have used a variety of structured (eg, sociodemographic, clinical) and unstructured (eg, electrocardiogram, phonocardiogram, and echocardiograms) and machine learning modeling approaches. Additional researches in diverse populations, including prospective clinical trials, are needed to evaluate the effectiveness and value of AI-enabled medical technologies in clinical care for patients with VHD.

Assessment of right ventricular size and function from cardiovascular magnetic resonance images using artificial intelligence.

BACKGROUND: Theoretically, artificial intelligence can provide an accurate automatic solution to measure right ventricular (RV) ejection fraction (RVEF) from cardiovascular magnetic resonance (CMR) images, despite the complex RV geometry. However, in our recent study, commercially available deep learning (DL) algorithms for RVEF quantification performed poorly in some patients. The current study was designed to test the hypothesis that quantification of RV function could be improved in these patients by using more diverse CMR datasets in addition to domain-specific quantitative performance evaluation metrics during the cross-validation phase of DL algorithm development. METHODS: We identified 100 patients from our prior study who had the largest differences between manually measured and automated RVEF values. Automated RVEF measurements were performed using the original version of the algorithm (DL1), an updated version (DL2) developed from a dataset that included a wider range of RV pathology and validated using multiple domain-specific quantitative performance evaluation metrics, and conventional methodology performed by a core laboratory (CORE). Each of the DL-RVEF approaches was compared against CORE-RVEF reference values using linear regression and Bland-Altman analyses. Additionally, RVEF values were classified into 3 categories: ≤ 35%, 35-50%, and ≥ 50%. Agreement between RVEF classifications made by the DL approaches and the CORE measurements was tested. RESULTS: CORE-RVEF and DL-RVEFs were obtained in all patients (feasibility of 100%). DL2-RVEF correlated with CORE-RVEF better than DL1-RVEF (r = 0.87 vs. r = 0.42), with narrower limits of agreement. As a result, DL2 algorithm also showed increasing accuracy from 0.53 to 0.80 for categorizing RV function. CONCLUSIONS: The use of a new DL algorithm cross-validated on a dataset with a wide range of RV pathology using multiple domain-specific metrics resulted in a considerable improvement in the accuracy of automated RVEF measurements. This improvement was demonstrated in patients whose images were the most challenging and resulted in the largest RVEF errors. These findings underscore the critical importance of this strategy in the development of DL approaches for automated CMR measurements.

Use of a novel 4D intracardiac echocardiography catheter to guide interventional electrophysiology procedures.

INTRODUCTION: Standard two-dimensional (2D), phased-array intracardiac echocardiography (ICE) is routinely used to guide interventional electrophysiology (EP) procedures. A novel four-dimensional (4D) ICE catheter (VeriSight Pro, Philips) can obtain 2D and three-dimensional (3D) volumetric images and cine-videos in real-time (4D). The purpose of this study was to determine the early feasibility and safety of this 4D ICE catheter during EP procedures. METHODS: The 4D ICE catheter was placed from the femoral vein in ten patients into various cardiac chambers to guide EP procedures requiring transseptal catheterization, including ablation for atrial fibrillation and left atrial appendage closure. 2D- and 3D-ICE images were acquired in real-time by the electrophysiologist. A dedicated imaging expert performed digital steering to optimize and postprocess 4D images. RESULTS: Eight patients underwent pulmonary vein isolation (cryoballoon in seven patients, pulsed field ablation in one, additional radiofrequency left atrial ablation in one). Two patients underwent left atrial appendage closure. High quality images of cardiac structures, transseptal catheterization equipment, guide sheaths, ablation tools, and closure devices were acquired with the ICE catheter tip positioned in the right atrium, left atrium, pulmonary vein, coronary sinus, right ventricle, and pulmonary artery. There were no complications. CONCLUSION: This is the first experience of a novel deflectable 4D ICE catheter used to guide EP procedures. 4D ICE imaging is safe and allows for acquisition of high-quality 2D and 3D images in real-time. Further use of 4D ICE will be needed to determine its added value for each EP procedure type.

12-Month outcomes of transcatheter tricuspid valve repair with the PASCAL system for severe tricuspid regurgitation.

OBJECTIVES: We investigated the durability of tricuspid regurgitation (TR) reduction and the clinical outcomes through 12 months after transcatheter tricuspid valve repair (TTVr) with the PASCAL Transcatheter Valve Repair System. BACKGROUND: TTVr has rapidly developed and demonstrated favorable acute outcomes, but longer follow-up data are needed. METHODS: Overall, 30 patients (age 77 ± 6 years; 57% female) received PASCAL implantation from September 2017 to May 2019 and completed a clinical follow-up at 12 months. RESULTS: The TR etiology was functional in 25 patients (83%), degenerative in three (10%), and mixed in two (7%). All patients had TR severe or greater (massive or torrential in 80%) and heart failure symptoms (90% in NYHA III or IV) under optimal medical treatment. Single-leaflet device attachment occurred in two patients. Moderate or less TR was achieved in 23/28 patients (82%) at 30 days, which was sustained at 12 months (86%). Two patients underwent repeat TTVr due to residual torrential TR (day 173) and recurrence of severe TR (day 280), respectively. One-year survival rate was 93%; 6 patients required rehospitalization due to acute heart failure. NYHA functional class I or II was achieved in 90% and 6-minute walk distance improved from 275 ± 122 m at baseline to 347 ± 112 m at 12-month (+72 ± 82 m, p < .01). There was no stroke, endocarditis, or device embolization during the follow-up. CONCLUSIONS: Twelve-month outcomes from this multicenter compassionate use experience with the PASCAL System demonstrated high procedural success, acceptable safety, and significant clinical improvement.

Incidence of catheter-associated right atrial thrombus detected by transthoracic echocardiogram.

INTRODUCTION: The development of right atrial (RA) thrombus (RAT) is a known complication of central venous catheter insertion (CVC). Deeper insertion of CVC within the RA may increase the risk for RAT development versus those placed at the superior vena cava (SVC)-RA junction. We sought to evaluate the incidence of catheter-associated RAT as detected by transthoracic echocardiograms (TTEs), characterize thrombi though multimodal imaging, and evaluate thrombi management with follow-up imaging. METHODS: A retrospective analysis was conducted of consecutive TTEs from our institution between October 1, 2018, and January 1, 2020, in which a venous catheter was visualized in the RA. Studies were reviewed in detail to determine the presence of suspected RAT. Demographic data, comorbidities, laboratory values, characteristics of the catheter and the thrombus, subsequent imaging and management, and outcomes were collected. RESULTS: A total of 364 TTEs were performed in 290 patients with a venous catheter visualized in the RA. Of these 290 patients, 15 had an imaging suspicion for RAT yielding an incidence of 5.2%. Management strategies included anticoagulation in 13 (86.7%) patients and catheter removal in 11 (73.3%) patients. At eight months of follow-up, 11 (73.3%) patients had resolution of RAT based on subsequent imaging. CONCLUSION: In patients with deeply placed CVC catheters, the incidental detection of RAT by TTE was not trivial. Anticoagulation and catheter removal and replacement, if deemed safe, were effective methods of thrombus management. RAT as a complication of CVCs must be accounted for when addressing factors that influence depth of CVC insertion.

Multimodality imaging to guide transcatheter treatment of severe degenerative tricuspid regurgitation with tricuspid valve-in-ring implantation and paravalvular leak closure.

Tricuspid valve (TV) degeneration after surgical repair with an annuloplasty ring is problematic as redo operation carries high mortality. This can be addressed with transcatheter therapies to implant a valve within in prior ring (tricuspid valve-in-ring). When an incomplete ring is present, paravalvular leak is commonly encountered after tricuspid valve-in-ring (TViR) implant; however, this can be addressed with paravalvular leak closure devices. Multimodality imaging including cardiac computed tomography and three-dimensional (3D) transesophageal echocardiography (TEE) are important for successful TViR implant. We report a case of tricuspid regurgitation after tricuspid repair with an incomplete annuloplasty ring and subsequent paravalvular leak closure.

A histopathologic schema to quantify the burden of cardiac amyloidosis: Relationship with survival and echocardiographic parameters.

BACKGROUND: Despite routine use of echocardiographic parameters to evaluate the severity of cardiac amyloidosis (CA), this methodology has not been well validated. We developed a histopathologic schema for quantifying CA burden and evaluated its relationship with clinical outcomes. Additionally, echocardiographic parameters were tested as potential noninvasive indices of CA burden. METHODS: We retrospectively studied 59 patients with CA (17 light chain, 42 transthyretin) who underwent endomyocardial biopsies. Light microscopy with staining was used to categorize CA burden as mild-to-moderate (<50%) or high (≥50%). Kaplan-Meier survival analysis was performed for the two groups. In 34 patients with good-quality echocardiograms, we measured left ventricular volumes, ejection fraction (EF), interventricular septal thickness (IVSt), posterior wall thickness (PWt), LV mass, lateral e'-velocity, and global longitudinal strain (GLS). These parameters were compared between the two groups. RESULTS: Thirty-five patients had mild-to-moderate and 24 severe amyloid burden. Kaplan-Meier curves demonstrated a trend toward worse mortality with high CA burden, which was more common and associated with higher mortality specifically in transthyretin-type patients. Echocardiography-derived IVSt, PWt, and LV mass were directly related to CA burden, while LV EF, e'-velocity, and GLS magnitude were inversely related to CA burden. CONCLUSIONS: Our findings provided a signal that CA burden is a clinically important entity with potentially valuable prognostic information. Echocardiographic parameters of LV anatomy and function correlate with histopathologic burden of CA, which is inversely related to survival. Further studies are needed to determine whether these parameters could be used as imaging biomarkers of treatment-related changes in CA burden.

Automated, machine learning-based, 3D echocardiographic quantification of left ventricular mass.

BACKGROUND: Although 3D echocardiography (3DE) circumvents many limitations of 2D echocardiography by allowing direct measurements of left ventricular (LV) mass, it is seldom used in clinical practice due to time-consuming analysis. A recently developed 3DE machine learning (ML) approach allows automated determination of LV mass. We aimed to evaluate the accuracy of this new approach by comparing it to cardiac magnetic resonance (CMR) reference and to conventional 3DE volumetric analysis. METHODS: We prospectively studied 23 patients who underwent 3DE (Philips EPIQ) and CMR imaging on the same day. Single-beat wide-angle 3D datasets of the left ventricle were acquired. LV mass was quantified using the new automated software (Philips HeartModel) with manual corrections when necessary and using conventional volumetric analysis (TomTec). CMR analysis was performed by manual slice-by-slice tracing of LV endo- and epicardial boundaries. Reproducibility of the ML approach was assessed using repeated measurements and quantified by intra-class correlation (ICC) and coefficients of variation (CoV). RESULTS: Automated LV mass measurements were feasible in 20 patients (87%). The results were similar to CMR-derived values (Bland-Altman bias 5 g, limits of agreement ±37 g) and also to the conventional 3DE analysis (bias 7 g, ±27 g). Processing time was considerably shorter: 1.02 ± 0.24 minutes (CMR: 2.20 ± 0.13 minutes; TomTec: 2.36 ± 0.09 minutes), although manual corrections were performed in most patients. Repeated measurements showed high reproducibility: ICC = 0.99; CoV = 4 ± 5%. CONCLUSIONS: 3D Echocardiography analysis of LV mass using novel ML-based algorithm is feasible, fast, and accurate and may thus facilitate the incorporation of 3DE measurements of LV mass into clinical practice.

An introduction to left ventricular strain.

PURPOSE OF REVIEW: The assessment of left ventricular function by two-dimensional (2D) transthoracic echocardiography (TTE) is conventionally performed by measuring the ejection fraction, which has been shown to have important prognostic implications. However, left ventricular ejection fraction (LVEF) has notable shortcomings, including limited reproducibility, suboptimal inter/intraobserver variability and dependence on load/volume. Furthermore, subclinical left ventricular dysfunction cannot be measured with LVEF. With the advent of left ventricular deformation (strain) analysis, a new and robust means for assessing left ventricular function has emerged. RECENT FINDINGS: Contemporary research and guidelines have attempted to standardize the definition, acquisition and measurement of left ventricular strain. In addition, multiple studies have sought to establish normal values for left ventricular strain in addition to evaluating the benefits and prognostic value of strain assessment. SUMMARY: This article reviews the definition of left ventricular strain, outlines the types of strain and reviews how strain is acquired and measured. In addition, the advantages of strain analysis over LVEF as well as the incremental prognostic value of strain are examined. We further review the challenges associated with strain imaging as well as outline the future of strain imaging.

Doppler Echocardiographic Phenotypes in Suspected 'Severe' Aortic Stenosis: Matrix-Based Approach to Diagnosis and Management.

BACKGROUND: Among patients with suspected severe aortic stenosis (AS), Doppler echocardiographic (DE) data are often discordant, and further analysis is required for accurate diagnosis and optimal management. In this study, an automated matrix-based approach was applied to an echocardiographic database of patients with AS that identified 5 discrete echocardiographic data patterns, 1 concordant and 4 discordant, each reflecting a particular pathophysiology/measurement error that guides further workup and management. METHODS: A primary/discovery cohort of consecutive echocardiographic studies with at least 1 DE parameter of severe AS and analogous data from an independent secondary/validation cohort were retrospectively analyzed. Parameter thresholds for inclusion were aortic valve area (AVA) <1.0 cm2, transaortic mean gradient (MG) ≥ 40 mmHg, and/or transaortic peak velocity (PV) ≥ 4.0 m/sec. Doppler velocity index (DVI) was also determined. Logic provided by an in-line SQL query embedded within the database was used to assign each patient to 1 of 5 discrete matrix patterns, each reflecting 1 or more specific pathophysiologies. Feasibility of automated pattern-driven triage of discordant cases was also evaluated. RESULTS: In both cohorts, data from each patient fitted only 1 data pattern. Of the 4,643 primary cohort patients, 39% had concordant parameters for severe AS and DVI <0.30 (pattern 1); 35% had AVA < 1.0 cm2, MG < 40 mm Hg, PV < 4 m/sec, DVI < 0.30 (pattern 2); 9% had MG ≥ 40 mmHg and/or PV ≥ 4 m/sec, DVI > 0.30 (pattern 3); 10% had AVA < 1.0 cm2, MG < 40 mmHg, PV < 4 m/sec, DVI >0.30 (pattern 4); and 7% had MG > 40 mmHg and/or PV ≥ 4 m/sec, AVA > 1.0 cm2, DVI < 0.30 (pattern 5). Findings were validated among the 387 secondary cohort patients in whom pattern distribution was remarkably similar. CONCLUSIONS: Matrix-based pattern recognition permits automated in-line identification of specific pathophysiology and/or measurement error among patients with suspected severe AS and discordant DE data.

Reverse Remodeling Effects of Sacubitril-Valsartan: Structural and Functional Optimization in Stage C Heart Failure.

Sacubitril-valsartan, an angiotensin receptor-neprilysin inhibitor, reduces all-cause mortality and the rate of heart failure hospitalizations in patients with heart failure with reduced ejection fraction. This study aimed to elucidate the benefits of initiating sacubitril-valsartan on ventricular remodeling in patients previously optimized on guideline-directed medical therapy. In this prospective, single-arm longitudinal study, 40 patients with heart failure with reduced ejection fraction who were optimized on guideline-directed medical therapy were transitioned to sacubitril-valsartan. The primary end point was the change in left ventricular (LV) volume at 1 year as assessed by 3-dimensional transthoracic echocardiography. Other echocardiographic end points included change in LV-function and change in right ventricular (RV) size and function. The mean age was 55 ± 12 years, and 63% were male. At 1 year, LV end-diastolic volume decreased from 242 ± 71 to 157 ± 57 ml (p <0.001) with a corresponding increase in LV ejection fraction from 32 ± 7% to 44 ± 9% (p <0.001). RV end-diastolic volume decreased from 151 ± 51 to 105 ±45 ml (p <0.001). Although RV ejection fraction did not change (51 ± 8 vs 51 ± 10; p = 0.35), RV global longitudinal strain improved from -14.9 ± 3.4 % to -19.3 ± 4.3% (p <0.001). When added to standard medical therapy for heart failure, sacubitril-valsartan induces significant remodeling of both the right and left ventricles as assessed by 3-dimensional echocardiography.

Novel echocardiographic pixel intensity quantification method for differentiating transthyretin cardiac amyloidosis from light chain cardiac amyloidosis and other phenocopies.

AIMS: Differentiating cardiac amyloidosis (CA) subtypes is important considering the significantly different therapies for transthyretin (ATTR)-CA and light chain (AL)-CA. Therefore, an echocardiographic method to distinguish ATTR-CA from AL-CA would provide significant value. We assessed a novel echocardiographic pixel intensity method to quantify myocardial calcification to differentiate ATTR-CA from phenocopies of CA and from AL-CA, specifically. METHODS AND RESULTS: 167 patients with ATTR-CA (n=53), AL-CA (n=32), hypertrophic cardiomyopathy (n=37), and advanced chronic kidney disease (n=45) were retrospectively evaluated. The septal reflectivity ratio (SRR) was measured as the average pixel intensity of the visible anterior septal wall divided by the average pixel intensity of the visible posterior lateral wall. SRR and other myocardial strain-based echocardiographic measures were evaluated with receiver operator characteristic analysis to evaluate accuracy in distinguishing ATTR-CA from AL-CA and other forms of left ventricular hypertrophy. Mean septal reflectivity ratio (SRR) was significantly higher in the ATTR-CA cohort compared to the other cohorts (p <0.001). SRR demonstrated the largest AUC (0.91, p<0.0001) for distinguishing ATTR from all other cohorts and specifically for distinguishing ATTR-CA from AL-CA (AUC=0.90, p<0.0001, specificity 96%, sensitivity 63%). There was excellent inter- and intra-operator reproducibility with an ICC of 0.91 (p <0.001) and 0.89 (p <0.001), respectively. CONCLUSION: The SRR is a reproducible and robust parameter for differentiating ATTR-CA from other phenocopies of CA and specifically ATTR-CA from AL-CA.

Cardiac Structural and Functional Remodeling After Transcatheter Mitral Valve in Valve Implantation: Early Changes and Prognostic Significance.

Background: Transcatheter mitral valve-in-valve (MViV) replacement has emerged as an alternative to redo mitral valve (MV) surgery for the management of failed bioprosthetic MVs. The degree of cardiac remodeling assessed by echocardiography has been shown to have prognostic implications in degenerative mitral regurgitation patients undergoing MV surgery. The impact of transcatheter MViV in patients with degenerative bioprosthetic MV failure on cardiac remodeling and its associated prognosis remains undescribed. Objectives: The aim of this study is to describe the early anatomic and functional changes of the left-sided chambers and right ventricle by echocardiography posttranscatheter MViV intervention and their impact on mortality outcomes. Additionally, we sought to analyze the outcome of heart failure in bioprosthetic MV failure patients undergoing transcatheter MViV replacement. Methods: We analyzed consecutive patients undergoing MViV intervention for symptomatic bioprosthetic MV failure. Echocardiograms before intervention and within 100 days postintervention were analyzed. A chart review was performed to obtain baseline characteristics, follow-up visits, 30-day heart failure and 1-year all-cause mortality outcomes. Results: A total of 62 patients (mean age 69 ± 13 years, 61% male) were included in the study. Most patients were undergoing MViV intervention for prosthetic mitral stenosis n = 48 (77.4%) and the rest for mitral regurgitation or mixed disease. Compared with baseline, significant reductions were observed in median left atrial volume (LAV; 103 [81-129] ml vs. 95.2 [74.5-117.5] ml, p < 0.01) and mean (SD) left atrial conduit strain (9.1% ± 5.2% vs. 10.8% ± 4.8%, p = 0.039) within 100 days postintervention. Early reduction in right ventricular free wall global longitudinal strain and fractional area change also occurred postintervention. No significant change in left ventricular chamber dimensions or ejection fraction was observed. During the 1-year follow up period, 5 (8%) patients died. While baseline LAV was not associated with 1-year all-cause mortality (OR 0.98 CI 0.95-1.01; p = 0.27), a change in LAV in the follow up period was associated with all-cause mortality at 1 year (OR 1.06 CI 1.01-1.12; p = 0.023). At 30 days postintervention, 65% of patients had an improvement in their New York Heart Association functional class. Conclusion: In this retrospective study of patients undergoing transcatheter MViV intervention for failed bioprosthetic MVs, early reverse remodeling of the left atrium occurs within 100 days postintervention and reduction in LAV is associated with reduced all-cause mortality at 1 year. In addition, there is significant improvement in heart failure symptoms at 30 days following intervention but further investigation into the longitudinal remodeling changes and long-term outcomes is needed.