Deep Learning-Based Prediction of Right Ventricular Ejection Fraction Using 2D Echocardiograms

BackgroundEvidence has shown the independent prognostic value of right ventricular (RV) function, even in patients with left-sided heart disease. The most widely used imaging technique to measure RV function is echocardiography; however, conventional 2-dimensional (2D) echocardiographic assessment is unable to leverage the same clinical information that 3-dimensional (3D) echocardiography-derived right ventricular ejection fraction (RVEF) can provide.ObjectivesThe authors aimed to implement a deep learning (DL)–based tool to estimate RVEF from 2D echocardiographic videos. In addition, they benchmarked the tool's performance against human expert reading and evaluated the prognostic power of the predicted RVEF values.MethodsThe authors retrospectively identified 831 patients with RVEF measured by 3D echocardiography. All 2D apical 4-chamber view echocardiographic videos of these patients were retrieved (n = 3,583), and each subject was assigned to either the training or the internal validation set (80:20 ratio). Using the videos, several spatiotemporal convolutional neural networks were trained to predict RVEF. The 3 best-performing networks were combined into an ensemble model, which was further evaluated in an external data set containing 1,493 videos of 365 patients with a median follow-up time of 1.9 years.ResultsThe ensemble model predicted RVEF with a mean absolute error of 4.57 percentage points in the internal and 5.54 percentage points in the external validation set. In the latter, the model identified RV dysfunction (defined as RVEF <45%) with an accuracy of 78.4%, which was comparable to an expert reader’s visual assessment (77.0%; P = 0.678). The DL-predicted RVEF values were associated with major adverse cardiac events independent of age, sex, and left ventricular systolic function (HR: 0.924 [95% CI: 0.862-0.990]; P = 0.025).ConclusionsUsing 2D echocardiographic videos alone, the proposed DL-based tool can accurately assess RV function, with similar diagnostic and prognostic power as 3D imaging.     

Prognostic Value of Right Ventricular Function in Patients With Suspected Myocarditis Undergoing Cardiac Magnetic Resonance

BackgroundRisk-stratification of myocarditis is based on functional parameters and tissue characterization of the left ventricle (LV), whereas right ventricular (RV) involvement remains mostly unrecognized.ObjectivesIn this study, the authors sought to analyze the prognostic value of RV involvement in myocarditis by cardiac magnetic resonance (CMR).MethodsPatients meeting the recommended clinical criteria for suspected myocarditis were enrolled at 2 centers. Exclusion criteria were the evidence of coronary artery disease, pulmonary artery hypertension or structural cardiomyopathy. Biventricular ejection fraction, edema according to T2-weighted images, and late gadolinium enhancement (LGE) were linked to a composite end point of major adverse cardiovascular events (MACE), including heart failure hospitalization, ventricular arrhythmia, recurrent myocarditis, and death.ResultsAmong 1,125 consecutive patients, 736 (mean age: 47.8 ± 16.1 years) met the clinical diagnosis of suspected myocarditis and were followed for 3.7 years. Signs of RV involvement (abnormal right ventricular ejection fraction [RVEF], RV edema, and RV-LGE) were present in 188 (25.6%), 158 (21.5%), and 92 (12.5%) patients, respectively. MACE occurred in 122 patients (16.6%) and was univariably associated with left ventricular ejection fraction (LVEF), LV edema, LV-LGE, RV-LGE, RV edema, and RVEF. In a series of nesting multivariable Cox regression models, the addition of RVEF (HR_adj: 0.974 [95% CI: 0.956-0.993]; P = 0.006) improved prognostication (chi-square test = 89.5; P = 0.001 vs model 1; P = 0.006 vs model 2) compared with model 1 including only clinical variables (chi-square test = 28.54) and model 2 based on clinical parameters, LVEF, and LV-LGE extent (chi-square test = 78.93).ConclusionsThis study emphasizes the role of RV involvement in myocarditis and demonstrates the independent and incremental prognostic value of RVEF beyond clinical variables, CMR tissue characterization, and LV function. (Inflammatory Cardiomyopathy Bern Registry [FlamBER]; NCT04774549; CMR Features in Patients With Suspected Myocarditis [CMRMyo]; NCT03470571)     

Using Deep-Learning Algorithms to Simultaneously Identify Right and Left Ventricular Dysfunction From the Electrocardiogram

ObjectivesThis study sought to develop DL models capable of comprehensively quantifying left and right ventricular dysfunction from ECG data in a large, diverse population.BackgroundRapid evaluation of left and right ventricular function using deep learning (DL) on electrocardiograms (ECGs) can assist diagnostic workflow. However, DL tools to estimate right ventricular (RV) function do not exist, whereas those to estimate left ventricular (LV) function are restricted to quantification of very low LV function only.MethodsA multicenter study was conducted with data from 5 New York City hospitals: 4 for internal testing and 1 serving as external validation. We created novel DL models to classify left ventricular ejection fraction (LVEF) into categories derived from the latest universal definition of heart failure, estimate LVEF through regression, and predict a composite outcome of either RV systolic dysfunction or RV dilation.ResultsWe obtained echocardiogram LVEF estimates for 147,636 patients paired to 715,890 ECGs. We used natural language processing (NLP) to extract RV size and systolic function information from 404,502 echocardiogram reports paired to 761,510 ECGs for 148,227 patients. For LVEF classification in internal testing, area under curve (AUC) at detection of LVEF ≤40%, 40% < LVEF ≤50%, and LVEF >50% was 0.94 (95% CI: 0.94-0.94), 0.82 (95% CI: 0.81-0.83), and 0.89 (95% CI: 0.89-0.89), respectively. For external validation, these results were 0.94 (95% CI: 0.94-0.95), 0.73 (95% CI: 0.72-0.74), and 0.87 (95% CI: 0.87-0.88). For regression, the mean absolute error was 5.84% (95% CI: 5.82%-5.85%) for internal testing and 6.14% (95% CI: 6.13%-6.16%) in external validation. For prediction of the composite RV outcome, AUC was 0.84 (95% CI: 0.84-0.84) in both internal testing and external validation.ConclusionsDL on ECG data can be used to create inexpensive screening, diagnostic, and predictive tools for both LV and RV dysfunction. Such tools may bridge the applicability of ECGs and echocardiography and enable prioritization of patients for further interventions for either sided failure progressing to biventricular disease.     

Cardiac Magnetic Resonance Assessment of Response to Cardiac Resynchronization Therapy and Programming Strategies

ObjectivesThe objective was to determine the feasibility and effectiveness of cardiac magnetic resonance (CMR) cine and strain imaging before and after cardiac resynchronization therapy (CRT) for assessment of response and the optimal resynchronization pacing strategy.BackgroundCMR with cardiac implantable electronic devices can safely provide high-quality right ventricular/left ventricular (LV) ejection fraction (RVEF/LVEF) assessments and strain.MethodsCMR with cine imaging, displacement encoding with stimulated echoes for the circumferential uniformity ratio estimate with singular value decomposition (CURE-SVD) dyssynchrony parameter, and scar assessment was performed before and after CRT. Whereas the pre-CRT scan constituted a single “imaging set” with complete volumetric, strain, and scar imaging, multiple imaging sets with complete strain and volumetric data were obtained during the post-CRT scan for biventricular pacing (BIVP), LV pacing (LVP), and asynchronous atrial pacing modes by reprogramming the device outside the scanner between imaging sets.Results100 CMRs with a total of 162 imaging sets were performed in 50 patients (median age 70 years [IQR: 50-86 years]; 48% female). Reduction in LV end-diastolic volumes (P = 0.002) independent of CRT pacing were more prominent than corresponding reductions in right ventricular end-diastolic volumes (P = 0.16). A clear dependence of the optimal CRT pacing mode (BIVP vs LVP) on the PR interval (P = 0.0006) was demonstrated. The LVEF and RVEF improved more with BIVP than LVP with PR intervals ≥240 milliseconds (P = 0.025 and P = 0.002, respectively); the optimal mode (BIVP vs LVP) was variable with PR intervals <240 milliseconds. A lower pre-CRT displacement encoding with stimulated echoes (DENSE) CURE-SVD was associated with greater improvements in the post-CRT CURE-SVD (r = −0.69; P < 0.001), LV end-systolic volume (r = −0.58; P < 0.001), and LVEF (r = −0.52; P < 0.001).ConclusionsCMR evaluation with assessment of multiple pacing modes during a single scan after CRT is feasible and provides useful information for patient care with respect to response and the optimal pacing strategy.     

Prognostic Implications of Left Atrial Stiffness Index in Heart Failure Patients With Preserved Ejection Fraction

BackgroundThe left atrium (LA) plays an important role in the pathophysiology and disease progression of heart failure with preserved ejection fraction (HFpEF).ObjectivesThis study sought to assess the prognostic potential of LA stiffness index in patients who have HFpEF.MethodsThis study retrospectively screened patients with elevated left ventricular end-diastolic pressure (≥16 mm Hg) and preserved ejection fraction (≥50%) between January 1, 2004, and December 31, 2019. All patients underwent left heart catheterization to measure left ventricular end-diastolic pressure. Among these, 307 patients who had suitable image quality for left peak atrial longitudinal strain (PALS) measurement were analyzed. The study population was classified into low LA stiffness (n = 178, early diastolic transmitral inflow velocity/mitral annulus early diastolic velocity [E/e′]/PALS ≤0.26) and high LA stiffness (n = 129, E/e′/PALS >0.26) according to the best LA stiffness index (E/e′/PALS) cutoff value. The primary outcome was a composite of mortality or hospitalization caused by heart failure during follow-up.ResultsLA stiffness index showed good correlations with E/e′ (r = 0.737; P < 0.001), LA volume index (r = 0.529; P < 0.001), right ventricular systolic pressure (r = 0.404; P < 0.001), and log N-terminal pro–B-type natriuretic peptide (r = 0.540; P < 0.001). LA stiffness index demonstrated better predictive performance than echocardiographic diastolic parameters did (P < 0.001). Patients with low LA stiffness had better clinical outcomes than those with high LA stiffness during a median follow-up of 6 years did (P < 0.001). In multivariable analysis, LA stiffness index was independently associated with increased risk of the composite endpoint of death or heart failure hospitalization (HR: 1.59 [95% CI: 1.01-2.51]; P = 0.044).ConclusionsIncreased LA stiffness was associated with increased risk for all-cause mortality and hospitalization caused by heart failure in patients who have HFpEF, and its prognostic role was more pronounced than that of indexes of left ventricular filling pressure.     

Lateral Wall Dysfunction Signals Onset of Progressive Heart Failure in Left Bundle Branch Block

ObjectivesThis study sought to investigate if contractile asymmetry between septum and left ventricular (LV) lateral wall drives heart failure development in patients with left bundle branch block (LBBB) and whether the presence of lateral wall dysfunction affects potential for recovery of LV function with cardiac resynchronization therapy (CRT).BackgroundLBBB may induce or aggravate heart failure. Understanding the underlying mechanisms is important to optimize timing of CRT.MethodsIn 76 nonischemic patients with LBBB and 11 controls, we measured strain using speckle-tracking echocardiography and regional work using pressure-strain analysis. Patients with LBBB were stratified according to LV ejection fraction (EF) ≥50% (EF_preserved), 36% to 49% (EF_mid), and ≤35% (EF_low). Sixty-four patients underwent CRT and were re-examined after 6 months.ResultsSeptal work was successively reduced from controls, through EF_preserved, EF_mid, and EF_low (all p < 0.005), and showed a strong correlation to left ventricular ejection fraction (LVEF; r = 0.84; p < 0.005). In contrast, LV lateral wall work was numerically increased in EF_preserved and EF_mid versus controls, and did not significantly correlate with LVEF in these groups. In EF_low, however, LV lateral wall work was substantially reduced (p < 0.005). There was a moderate overall correlation between LV lateral wall work and LVEF (r = 0.58; p < 0.005). In CRT recipients, LVEF was normalized (≥50%) in 54% of patients with preserved LV lateral wall work, but only in 13% of patients with reduced LV lateral wall work (p < 0.005).ConclusionsIn early stages, LBBB-induced heart failure is associated with impaired septal function but preserved lateral wall function. The advent of LV lateral wall dysfunction may be an optimal time-point for CRT.     

Prognostic Value of Pulmonary Transit Time and Pulmonary Blood Volume Estimation Using Myocardial Perfusion CMR

ObjectivesThe purpose of this study was to explore the prognostic significance of PTT and PBVi using an automated, inline method of estimation using CMR.BackgroundPulmonary transit time (PTT) and pulmonary blood volume index (PBVi) (the product of PTT and cardiac index), are quantitative biomarkers of cardiopulmonary status. The development of cardiovascular magnetic resonance (CMR) quantitative perfusion mapping permits their automated derivation, facilitating clinical adoption.MethodsIn this retrospective 2-center study of patients referred for clinical myocardial perfusion assessment using CMR, analysis of right and left ventricular cavity arterial input function curves from first pass perfusion was performed automatically (incorporating artificial intelligence techniques), allowing estimation of PTT and subsequent derivation of PBVi. Association with major adverse cardiovascular events (MACE) and all-cause mortality were evaluated using Cox proportional hazard models, after adjusting for comorbidities and CMR parameters.ResultsA total of 985 patients (67% men, median age 62 years [interquartile range (IQR): 52 to 71 years]) were included, with median left ventricular ejection fraction (LVEF) of 62% (IQR: 54% to 69%). PTT increased with age, male sex, atrial fibrillation, and left atrial area, and reduced with LVEF, heart rate, diabetes, and hypertension (model r² = 0.57). Over a median follow-up period of 28.6 months (IQR: 22.6 to 35.7 months), MACE occurred in 61 (6.2%) patients. After adjusting for prognostic factors, both PTT and PBVi independently predicted MACE, but not all-cause mortality. There was no association between cardiac index and MACE. For every 1 × SD (2.39-s) increase in PTT, the adjusted hazard ratio for MACE was 1.43 (95% confidence interval [CI]: 1.10 to 1.85; p = 0.007). The adjusted hazard ratio for 1 × SD (118 ml/m²) increase in PBVi was 1.42 (95% CI: 1.13 to 1.78; p = 0.002).ConclusionsPulmonary transit time (and its derived parameter pulmonary blood volume index), measured automatically without user interaction as part of CMR perfusion mapping, independently predicted adverse cardiovascular outcomes. These biomarkers may offer additional insights into cardiopulmonary function beyond conventional predictors including ejection fraction.     

Right Ventricular Contraction Patterns in Patients Undergoing Transcatheter Tricuspid Valve Repair for Severe Tricuspid Regurgitation

ObjectivesThis study investigated patterns of right ventricular (RV) contraction by using cardiac magnetic resonance (CMR) imaging in patients undergoing transcatheter tricuspid valve repair (TTVR).BackgroundThe role of RV function in patients with severe tricuspid regurgitation undergoing TTVR is poorly understood.MethodsGlobal RV dysfunction was defined as CMR-derived RV ejection fraction (RVEF) ≤45% and longitudinal RV dysfunction was defined as tricuspid annular plane systolic excursion (TAPSE) <17 mm on echocardiography. Patients were stratified into 3 types of RV contraction: type I, TAPSE ≥17 and RVEF >45%; type II, TAPSE <17 and RVEF >45%; and type III, TAPSE <17 and RVEF ≤45%. CMR feature tracking was performed to assess longitudinal and circumferential RV strain. The primary outcome was a composite of all-cause mortality or first heart failure hospitalization.ResultsOf 79 patients (median age 79 years, 51% female), 18 (23%) presented with global and 40 (51%) presented with longitudinal RV dysfunction. The composite outcome occurred in 22 patients (median follow-up 362 days). Global RV dysfunction but not longitudinal RV dysfunction (hazard ratio: 6.62; 95% confidence interval: 2.77-15.77; and hazard ratio: 1.30; 95% confidence interval: 0.55-3.08, respectively) was associated with the composite outcome. Compared with type I RV contraction, patients with type II RV contraction exhibited increased circumferential strain, with a preservation of RVEF despite diminished longitudinal strain. Patients with type III RV contraction exhibited both diminished longitudinal and circumferential strain, resulting in an impaired RVEF. Patients with type III RV contraction showed the worst survival (P < 0.001).ConclusionsGlobal RV dysfunction is a predictor of outcomes among TTVR patients. Tricuspid regurgitation patients can be stratified into 3 types of RV contraction, in which a loss of longitudinal function can be compensated by increasing circumferential function, preserving RVEF and favorable outcomes.     

Entropy as a Measure of Myocardial Tissue Heterogeneity in Patients With Ventricular Arrhythmias

ObjectivesThe authors investigated the incremental prognostic value of entropy, a novel measure of myocardial tissue heterogeneity by cardiac magnetic resonance (CMR) imaging in patients presenting with ventricular arrhythmias (VAs).BackgroundCMR can characterize myocardial areas serving as arrhythmogenic substrate.MethodsConsecutive patients undergoing CMR imaging for VAs were followed for major adverse cardiac events (MACEs) defined by all-cause death, incident VAs requiring therapy, or heart failure hospitalization. Entropy was derived from the probability distribution of pixel signal intensities of the left ventricular (LV) myocardium.ResultsA total of 583 patients (age 54 ± 15 years, female 39%, left ventricular ejection fraction [LVEF] 54 ± 13%) were followed for a median of 4.4 years and experienced 141 MACEs. Entropy showed strong unadjusted association with MACE (HR: 1.88; 95% CI: 1.63-2.17; P < 0.001). In a multivariable model including LVEF, QRS duration, late gadolinium enhancement, and presenting arrhythmia, entropy maintained independent association with MACE (HR: 1.61; 95% CI: 1.32-1.96; P < 0.001). Entropy was further significantly associated with MACE in patients without myocardial scar (HR: 2.43; 95% CI: 1.55-3.82; P < 0.001) and in those presenting with nonsustained VAs (HR: 2.16; 95% CI: 1.43-3.25; P < 0.001). Addition of LV entropy to the baseline multivariable model significantly improved model performance (C-statistic improvement: 0.725 to 0.754; P = 0.003) and risk reclassification.ConclusionsIn patients with VAs, CMR-assessed LV entropy was independently associated with MACE and provided incremental prognostic value, on top of LVEF and late gadolinium enhancement. LV entropy assessment may help risk stratification in patients with absence of myocardial scar or with nonsustained VAs.     

Improving the Characterization of Stage A and B Heart Failure by Adding Global Longitudinal Strain

BackgroundCurrent guidelines distinguish stage B heart failure (SBHF) (asymptomatic left ventricular [LV] dysfunction) from stage A heart failure (SAHF) (asymptomatic with heart failure [HF] risk factors) on the basis of myocardial infarction, LV remodeling (hypertrophy or reduced ejection fraction [EF]) or valvular disease. However, subclinical HF with preserved EF may not be identified with these criteria.ObjectivesThe purpose of this study was to assess the prediction of incident HF with global longitudinal strain (GLS) in patients with SAHF and SBHF.MethodsThe authors analyzed echocardiograms (including GLS) in 447 patients (age 65 ± 11 years; 77% male) enrolled in a prospective study of HF in individuals at risk of incident HF, with normal or mildly impaired EF (≥40%). Long-term follow-up was obtained via data linkage. Analysis was performed using a competing risks model.ResultsAfter a median of 9 years of follow-up, 50 (10%) of the 447 patients had new HF admissions, and 87 (18%) died. In multivariable analysis, all imaging variables were independent predictors of HF admissions, including left ventricular ejection fraction (LVEF) (HR: 0.97 [95% CI: 0.94-0.99]), LV mass index (HR: 1.01 [95% CI: 1.00-1.02]), left atrial volume index (HR: 1.02 [95% CI: 1.00-1.05]), and E/e′ (HR: 1.05 [95% CI: 1.01-1.24]), incremental to clinical variables (age and Charlson comorbidity score). However, the addition of GLS provided value incremental to both clinical and other echocardiographic parameters (P = 0.004). Impaired GLS (<18%) (HR: 4.09 [95% CI: 1.87-8.92]) was independent and incremental to all clinical and other echocardiographic variables in predicting HF, and impaired LVEF, left ventricular hypertrophy, left atrial enlargement, high E/e′, or SBHF were not predictive.ConclusionsThe inclusion of GLS as a criterion for SBHF would add independent and incremental information to standard markers of SBHF for the prediction of subsequent HF admissions.     

Fully Automated,Quality-Controlled Cardiac Analysis From CMR: Validation and Large-Scale Application to Characterize Cardiac Function

ObjectivesThis study sought to develop a fully automated framework for cardiac function analysis from cardiac magnetic resonance (CMR), including comprehensive quality control (QC) algorithms to detect erroneous output.BackgroundAnalysis of cine CMR imaging using deep learning (DL) algorithms could automate ventricular function assessment. However, variable image quality, variability in phenotypes of disease, and unavoidable weaknesses in training of DL algorithms currently prevent their use in clinical practice.MethodsThe framework consists of a pre-analysis DL image QC, followed by a DL algorithm for biventricular segmentation in long-axis and short-axis views, myocardial feature-tracking (FT), and a post-analysis QC to detect erroneous results. The study validated the framework in healthy subjects and cardiac patients by comparison against manual analysis (n = 100) and evaluation of the QC steps’ ability to detect erroneous results (n = 700). Next, this method was used to obtain reference values for cardiac function metrics from the UK Biobank.ResultsAutomated analysis correlated highly with manual analysis for left and right ventricular volumes (all r > 0.95), strain (circumferential r = 0.89, longitudinal r > 0.89), and filling and ejection rates (all r ≥ 0.93). There was no significant bias for cardiac volumes and filling and ejection rates, except for right ventricular end-systolic volume (bias +1.80 ml; p = 0.01). The bias for FT strain was <1.3%. The sensitivity of detection of erroneous output was 95% for volume-derived parameters and 93% for FT strain. Finally, reference values were automatically derived from 2,029 CMR exams in healthy subjects.ConclusionsThe study demonstrates a DL-based framework for automated, quality-controlled characterization of cardiac function from cine CMR, without the need for direct clinician oversight.     

Clinical Validation of a 3-Dimensional Ultrafast Cardiac Magnetic Resonance Protocol Including Single Breath-Hold 3-Dimensional Sequences

ObjectivesThis study sought to clinically validate a novel 3-dimensional (3D) ultrafast cardiac magnetic resonance (CMR) protocol including cine (anatomy and function) and late gadolinium enhancement (LGE), each in a single breath-hold.BackgroundCMR is the reference tool for cardiac imaging but is time-consuming.MethodsA protocol comprising isotropic 3D cine (Enhanced sensitivity encoding [SENSE] by Static Outer volume Subtraction [ESSOS]) and isotropic 3D LGE sequences was compared with a standard cine+LGE protocol in a prospective study of 107 patients (age 58 ± 11 years; 24% female). Left ventricular (LV) mass, volumes, and LV and right ventricular (RV) ejection fraction (LVEF, RVEF) were assessed by 3D ESSOS and 2D cine CMR. LGE (% LV) was assessed using 3D and 2D sequences.ResultsThree-dimensional and LGE acquisitions lasted 24 and 22 s, respectively. Three-dimensional and LGE images were of good quality and allowed quantification in all cases. Mean LVEF by 3D and 2D CMR were 51 ± 12% and 52 ± 12%, respectively, with excellent intermethod agreement (intraclass correlation coefficient [ICC]: 0.96; 95% confidence interval [CI]: 0.94 to 0.97) and insignificant bias. Mean RVEF 3D and 2D CMR were 60.4 ± 5.4% and 59.7 ± 5.2%, respectively, with acceptable intermethod agreement (ICC: 0.73; 95% CI: 0.63 to 0.81) and insignificant bias. Both 2D and 3D LGE showed excellent agreement, and intraobserver and interobserver agreement were excellent for 3D LGE.ConclusionsESSOS single breath-hold 3D CMR allows accurate assessment of heart anatomy and function. Combining ESSOS with 3D LGE allows complete cardiac examination in <1 min of acquisition time. This protocol expands the indication for CMR, reduces costs, and increases patient comfort.     

Cardiac resynchronisation therapy optimisation of interventricular delay by the systolic dyssynchrony index: A comparative,randomised, 12-month follow-up study

BackgroundThe aim of our study was to compare the effect of interventricular (VV) delay optimisation in CRT recipients on the basis of systolic dyssynchrony index (SDI) derived from the three-dimensional echocardiography (3DE) versus QRS width assessment on left ventricle volume reduction at the 12-month follow-up.MethodsWe included 63 patients with recently implanted CRT in this randomised, open-label trial. Patients were randomised to VV delay optimisation according to QRS complex width measurement in group 1 (n = 31) to obtain the narrowest QRS complex and SDI in group 2 (n = 32) to achieve its lowest possible value. We evaluated left ventricular end-systolic volume (LVESv), left ventricular ejection fraction (LVEF) and SDI by 3DE before CRT implantation and at a 12-month follow-up in all the patients. We also obtained the New York Heart Association functional class, the 6-minute walk test, the quality of life questionnaire and the level of NT-proBNP.ResultsThe number of volumetric responders was similar in both groups (17 vs. 20, P = 0.786). There were also no significant differences in the reduction of LVESv (−41 ± 55 mL vs. - 61 ± 51 mL, P = 0.111), improvement in LVEF (+10.1 ± 10.6% vs. + 13.0 ± 9.9%, P = 0.213) or differences in clinical outcomes between both groups at the 12-month follow-up.ConclusionCRT optimisation of interventricular delay using SDI compared with QRS width assessment did not reveal any significant difference in terms of volumetric and clinical response at the 12-month follow-up.     

Prognostic Value of RV Abnormalities on CMR in Patients With Known or Suspected Cardiac Sarcoidosis

BackgroundLeft ventricular abnormalities in cardiac sarcoidosis (CS) are associated with adverse cardiovascular events, whereas the prognostic value of right ventricular (RV) involvement found on cardiac magnetic resonance is unclear.ObjectivesThis study aimed to systematically assess the prognostic value of right ventricular ejection fraction (RVEF) and RV late gadolinium enhancement (LGE) in known or suspected CS.MethodsThis study was prospectively registered in PROSPERO (CRD42022302579). PubMed, Embase, and Web of Science were searched to identify studies that evaluated the association between RVEF or RV LGE on clinical outcomes in CS. A composite endpoint of all-cause death, cardiovascular events, or sudden cardiac death (SCD) was used. A meta-analysis was performed to determine the pooled risk ratio (RR) for these adverse events. The calculated sensitivity, specificity, and area under the curve with 95% CIs were weighted and summarized.ResultsEight studies including a total of 899 patients with a mean follow-up duration of 3.2 ± 0.7 years were included. The pooled RR of RV systolic dysfunction was 3.1 (95% CI: 1.7-5.5; P < 0.01) for composite events and 3.0 (95% CI: 1.3-7.0; P < 0.01) for SCD events. In addition, CS patients with RV LGE had a significant risk for composite events (RR: 4.8 [95% CI: 2.4-9.6]; P < 0.01) and a higher risk for SCD (RR: 9.5 [95% CI: 4.4-20.5]; P < 0.01) than patients without RV LGE. Furthermore, the pooled area under the curve, sensitivity, and specificity of RV LGE for identifying patients with CS who were at highest SCD risk were 0.8 (95% CI: 0.8-0.9), 69% (95% CI: 50%-84%), and 90% (95% CI: 70%-97%), respectively.ConclusionsIn patients with known or suspected CS, RVEF and RV LGE were both associated with adverse events. Furthermore, RV LGE shows good discrimination in identifying CS patients at high risk of SCD.     

Left Atrial Strain Has Superior Prognostic Value to Ventricular Function and Delayed-Enhancement in Dilated Cardiomyopathy

BackgroundThe left atrium is an early sensor of left ventricular (LV) dysfunction. Still, the prognostic value of left atrial (LA) function (strain) on cardiac magnetic resonance (CMR) in dilated cardiomyopathy (DCM) remains unknown.ObjectivesThe goal of this study was to evaluate the prognostic value of CMR-derived LA strain in DCM.MethodsPatients with DCM from the Maastricht Cardiomyopathy Registry with available CMR imaging were included. The primary endpoint was the combination of sudden or cardiac death, heart failure (HF) hospitalization, or life-threatening arrhythmias. Given the nonlinearity of continuous variables, cubic spline analysis was performed to dichotomize.ResultsA total of 488 patients with DCM were included (median age: 54 [IQR: 46-62] years; 61% male). Seventy patients (14%) reached the primary endpoint (median follow-up: 6 [IQR: 4-9] years). Age, New York Heart Association (NYHA) functional class >II, presence of late gadolinium enhancement (LGE), LV ejection fraction (LVEF), LA volume index (LAVI), LV global longitudinal strain (GLS), and LA reservoir and conduit strain were univariably associated with the outcome (all P < 0.02). LA conduit strain was a stronger predictor of outcome compared with reservoir strain. LA conduit strain, NYHA functional class >II, and LGE remained associated in the multivariable model (LA conduit strain HR: 3.65 [95% CI: 2.01-6.64; P < 0.001]; NYHA functional class >II HR: 1.81 [95% CI: 1.05-3.12; P = 0.033]; and LGE HR: 2.33 [95% CI: 1.42-3.85; P < 0.001]), whereas age, N-terminal pro–B-type natriuretic peptide, LVEF, left atrial ejection fraction, LAVI, and LV GLS were not. Adding LA conduit strain to other independent predictors (NYHA functional class and LGE) significantly improved the calibration, accuracy, and reclassification of the prediction model (P < 0.05).ConclusionsLA conduit strain on CMR is a strong independent prognostic predictor in DCM, superior to LV GLS, LVEF, and LAVI and incremental to LGE. Including LA conduit strain in DCM patient management should be considered to improve risk stratification.     

Improved Risk Stratification for Ventricular Arrhythmias and Sudden Death in Patients With Nonischemic Dilated Cardiomyopathy

BackgroundRisk stratification for ventricular arrhythmias (VA) and sudden death in nonischemic dilated cardiomyopathy (DCM) remains suboptimal.ObjectivesThe goal of this study was to provide an improved risk stratification algorithm for VA and sudden death in DCM.MethodsThis was a retrospective cohort study of consecutive patients with DCM who underwent cardiac magnetic resonance with late gadolinium enhancement (LGE) at 2 tertiary referral centers. The combined arrhythmic endpoint included appropriate implantable cardioverter-defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest, and sudden death.ResultsIn 1,165 patients with a median follow-up of 36 months, LGE was an independent and strong predictor of the arrhythmic endpoint (hazard ratio: 9.7; p < 0.001). This association was consistent across all strata of left ventricular ejection fraction (LVEF). Epicardial LGE, transmural LGE, and combined septal and free-wall LGE were all associated with heightened risk. A simple algorithm combining LGE and 3 LVEF strata (i.e., ≤20%, 21% to 35%, >35%) was significantly superior to LVEF with the 35% cutoff (Harrell’s C statistic: 0.8 vs. 0.69; area under the curve: 0.82 vs. 0.7; p < 0.001) and reclassified the arrhythmic risk of 34% of patients with DCM. LGE-negative patients with LVEF 21% to 35% had low risk (annual event rate 0.7%), whereas those with high-risk LGE distributions and LVEF >35% had significantly higher risk (annual event rate 3%; p = 0.007).ConclusionsIn a large cohort of patients with DCM, LGE was found to be a significant, consistent, and strong predictor of VA or sudden death. Specific high-risk LGE distributions were identified. A new clinical algorithm integrating LGE and LVEF significantly improved the risk stratification for VA and sudden death, with relevant implications for implantable cardioverter-defibrillator allocation.     

Sex Differences in LV Remodeling and Hemodynamics in Aortic Stenosis: Sex-Specific Criteria for Severe Stenosis?

BackgroundThe current criteria for aortic stenosis (AS) severity have not incorporated sex-related differences.ObjectivesThe authors investigated sex-related serial changes in left ventricular (LV) structure/function and hemodynamics in AS.MethodsSerial echocardiograms of patients with severe AS (time 0; aortic valve area [AVA] ≤1 cm²) and ≥1 previous echocardiogram were compared between sexes.ResultsOf 927 patients (time 0: AVA 0.87 ± 0.11 cm², peak velocity 4.03 ± 0.65 m/s, mean Doppler systolic pressure gradient [MG] 40.6 ± 13.1 mm Hg), 393 (42%) were women. Women had smaller body surface area (BSA) (1.77 ± 0.22 m² vs 2.03 ± 0.20 m²; P < 0.001), lower stroke volume (SV) (81.1 ± 17.2 mL vs 88.3 ± 18.6 mL; P < 0.001), and more frequent low-gradient severe AS (n = 196 [50%] vs n = 181 [34%]; P < 0.001). Women consistently had smaller AVA, indexed AVA (AVAi), peak velocity, and MG than men. The difference in aortic valve gradient lessened when AVAi ≤0.6 cm²/m² was applied as severe AS (n = 694, women 43%, AVA 0.95 ± 0.17 cm², AVAi 0.50 ± 0.07 cm²/m²). Peak velocity (3.83 ± 0.66 m/s) and MG (36.5 ± 13.2 mm Hg) were lower based on AVAi severity criteria compared to those based on AVA. Men had a lower left ventricular ejection fraction (LVEF) (55.8% ± 14.8% vs 61.1% ± 11.7%; P < 0.001) and greater reduction in SV (?13.3 ± 19.6 mL vs ?7.4 ± 16.4 mL; P < 0.001) as AS progressed from moderate to severe. Concentric LV hypertrophy was more common and E/e? higher in women (21.2 ± 10.9 vs 18.8 ± 9.1; P < 0.001). SV, LVEF, AVA, peak velocity, and MG became precipitously worse when AVA reached 1.2 cm² in both sexes.ConclusionsSmaller BSA in women yields lower SV, resulting in lower aortic valve gradient than men. Indexed parameters by BSA are thus important in sex-related differences of aortic valve hemodynamics, but AVAi ≤0.6 cm²/m² includes individuals with moderate AS. Elevated filling pressure is more common in women. Men experience a larger reduction in SV and LVEF as AS progresses. The definition of AS severity may require different criteria between sexes.     

Prognostic Value of Initial Left Ventricular Remodeling in Patients With Reperfused STEMI

ObjectivesThis study sought to establish the best definition of left ventricular adverse remodeling (LVAR) to predict outcomes and determine whether its assessment adds prognostic information to that obtained by early cardiac magnetic resonance (CMR).BackgroundLVAR, usually defined as an increase in left ventricular end-diastolic volume (LVEDV) is the main cause of heart failure after an ST-segment elevated myocardial infarction; however, the role of assessment of LVAR in predicting cardiovascular events remains controversial.MethodsPatients with ST-segment elevated myocardial infarction who received percutaneous coronary intervention within 6 h of symptom onset were included (n = 498). CMR was performed during hospitalization (6.2 ± 2.6 days) and after 6 months (6.1 ± 1.8 months). The optimal threshold values of the LVEDV increase and the LV ejection fraction decrease associated with the primary endpoint were ascertained. Primary outcome was a composite of cardiovascular mortality, hospitalization for heart failure, or ventricular arrhythmia.ResultsThe study was completed by 374 patients. Forty-nine patients presented the primary endpoint during follow-up (72.9 ± 42.8 months). Values that maximized the ability to identify patients with and without outcomes were a relative rise in LVEDV of 15% (hazard ratio [HR]: 2.1; p = 0.007) and a relative fall in LV ejection fraction of 3% (HR: 2.5; p = 0.001). However, the predictive model (using C-statistic analysis) failed to demonstrate that direct observation of LVAR at 6 months adds information to data from early CMR in predicting outcomes (C-statistic: 0.723 vs. 0.795).ConclusionsThe definition of LVAR that best predicts adverse cardiovascular events should consider both the increase in LVEDV and the reduction in LV ejection fraction. However, assessment of LVAR does not improve information provided by the early CMR.     

Progression of Myocardial Fibrosis in Nonischemic DCM and Association With Mortality and Heart Failure Outcomes

ObjectivesThe purpose of this study was to assess whether the presence and extent of fibrosis changes over time in patients with nonischemic, dilated cardiomyopathy (DCM) receiving optimal medical therapy and the implications of any such changes on left ventricular ejection fraction (LVEF) and clinical outcomes.BackgroundMyocardial fibrosis on cardiovascular magnetic resonance (CMR) imaging has emerged as important risk marker in patients with DCM.MethodsIn total, 85 patients (age 56 ± 15 years, 45% women) with DCM underwent serial CMR (median interval 1.5 years) for assessment of LVEF and fibrosis. The primary outcome was all-cause mortality; the secondary outcome was a composite of heart failure hospitalization, aborted sudden cardiac death, left ventricular (LV) assist device implantation, or heart transplant.ResultsOn CMR-1, fibrosis (median 0.0 [interquartile range: 0% to 2.6%]) of LV mass was noted in 34 (40%) patients. On CMR-2, regression of fibrosis was not seen in any patient. Fibrosis findings were stable in 70 (82%) patients. Fibrosis progression (increase >1.8% of LV mass or new fibrosis) was seen in 15 patients (18%); 46% of these patients had no fibrosis on CMR-1. Although fibrosis progression was on aggregate associated with adverse LV remodeling and decreasing LVEF (40 ± 7% to 34 ± 10%; p < 0.01), in 60% of these cases the change in LVEF was minimal (<5%). Fibrosis progression was associated with increased hazards for all-cause mortality (hazard ratio: 3.4 [95% confidence interval: 1.5 to 7.9]; p < 0.01) and heart failure–related complications (hazard ratio: 3.5 [95% confidence interval: 1.5 to 8.1]; p < 0.01) after adjustment for clinical covariates including LVEF.ConclusionsOnce myocardial replacement fibrosis in DCM is present on CMR, it does not regress in size or resolve over time. Progressive fibrosis is often associated with minimal change in LVEF and identifies a high-risk cohort.