Right Ventricular Abnormalities on Cardiovascular Magnetic Resonance Imaging in Patients With Sarcoidosis

ObjectivesThis study aimed to determine the prevalence on cardiac magnetic resonance (CMR) of right ventricular (RV) systolic dysfunction and RV late gadolinium enhancement (LGE), their determinants, and their influences on long-term adverse outcomes in patients with sarcoidosis.BackgroundIn patients with sarcoidosis, RV abnormalities have been described on many imaging modalities. On CMR, RV abnormalities include RV systolic dysfunction quantified as an abnormal right ventricular ejection fraction (RVEF), and RV LGE.MethodsConsecutive patients with biopsy-proven sarcoidosis who underwent CMR for suspected cardiac involvement were studied. They were followed for 2 endpoints: all-cause death, and a composite arrhythmic endpoint of sudden cardiac death or significant ventricular arrhythmia.ResultsAmong 290 patients, RV systolic dysfunction (RVEF <40% in men and <45% in women) and RV LGE were present in 35 (12.1%) and 16 (5.5%), respectively. The median follow-up time was 3.2 years (interquartile range [IQR]: 1.6 to 5.7 years) for all-cause death and 3.0 years (IQR: 1.4 to 5.5 years) for the arrhythmic endpoint. On Cox proportional hazards regression multivariable analyses, only RVEF was independently associated with all-cause death (hazard ratio [HR]: 1.05 for every 1% decrease; 95% confidence interval [CI]: 1.01 to 1.09; p = 0.022) after adjustment for left ventricular EF, left ventricular LGE extent, and the presence of RV LGE. RVEF was not associated with the arrhythmic endpoint (HR: 1.01; 95% CI: 0.96 to 1.06; p = 0.67). Conversely, RV LGE was not associated with all-cause death (HR: 2.78; 95% CI: 0.36 to 21.66; p = 0.33), while it was independently associated with the arrhythmic endpoint (HR: 5.43; 95% CI: 1.25 to 23.47; p = 0.024).ConclusionsIn this study of patients with sarcoidosis, RV systolic dysfunction and RV LGE had distinct prognostic associations; RV systolic dysfunction but not RV LGE was independently associated with all-cause death, whereas RV LGE but not RV systolic dysfunction was independently associated with sudden cardiac death or significant ventricular arrhythmia. These findings may indicate distinct implications for the management of RV abnormalities in sarcoidosis.     

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.     

Native T1 Mapping,Extracellular Volume Mapping,and Late Gadolinium Enhancement in Cardiac Amyloidosis: A Meta-Analysis

ObjectivesThis study aimed to compare the diagnostic and prognostic performance of native T1 mapping (T1), extracellular volume (ECV) mapping, and late gadolinium enhancement (LGE) imaging for evaluating cardiac amyloidosis (CA).BackgroundCA is a progressive infiltrative process in the extracellular space that is often underdiagnosed and holds a poor prognosis. Cardiac magnetic resonance (CMR) offers novel techniques for detecting and quantifying the disease burden of CA.MethodsWe searched PubMed for published studies using native T1, ECV, or LGE to diagnose and prognosticate CA. A total of 18 diagnostic (n = 2,015) and 13 prognostic studies (n = 1,483) were included for analysis. Pooled sensitivities, specificities, diagnostic odds ratios (DORs) of all diagnostic tests were assessed by bivariate analysis. Pooled hazard ratios (HRs) for mortality for the 3 techniques were determined.ResultsBivariate comparison showed that ECV (DOR: 84.6; 95% confidence interval [CI]: 30.3 to 236.2) had a significantly higher DOR for CA than LGE (DOR: 20.1; 95% CI: 9.1 to 44.1; p = 0.03 vs. ECV). There was no significant difference between LGE and native T1 for sensitivity, specificity, and DOR. HR was significantly higher for ECV (HR: 4.27; 95% CI: 2.87 to 6.37) compared with LGE (HR: 2.60; 95% CI: 1.90 to 3.56; p = 0.03 vs. ECV) and native T1 (HR: 2.04; 95% CI: 1.24 to 3.37; p = 0.01 vs. ECV).ConclusionsECV demonstrates a higher diagnostic OR for assessing cardiac amyloid than LGE and a higher HR for adverse events compared with LGE and native T1. In addition, native T1 showed similar sensitivity and specificity as ECV and LGE without requiring contrast material. Although limited by study heterogeneity, this meta-analysis suggests that ECV provides high diagnostic and prognostic utility for the assessment of cardiac amyloidosis.     

Diagnostic Accuracy of Cardiovascular Magnetic Resonance for Cardiac Transplant Rejection: A Meta-Analysis

ObjectivesThe aim of this meta-analysis was to assess the diagnostic performance of various CMR imaging parameters for evaluating acute cardiac transplant rejection.BackgroundEndomyocardial biopsy is the current gold standard for detection of acute cardiac transplant rejection. Cardiac magnetic resonance (CMR) is uniquely capable of myocardial tissue characterization and may be useful as a noninvasive alternative for the diagnosis of graft rejection.MethodsPubMed and Web of Science were searched for relevant publications reporting on the use of CMR myocardial tissue characterization for detection of acute cardiac transplant rejection with endomyocardial biopsy as the reference standard. Pooled sensitivity, specificity, and hierarchical modeling–based summary receiver-operating characteristic curves were calculated.ResultsOf 478 papers, 10 studies comprising 564 patients were included. The sensitivity and specificity for the detection of acute cardiac transplant rejection were 84.6 (95% CI: 65.6-94.0) and 70.1 (95% CI: 54.2-82.2) for T1, 86.5 (95% CI: 72.1-94.1) and 85.9 (95% CI: 65.2-94.6) for T2, 91.3 (95% CI: 63.9-98.4) and 67.6 (95% CI: 56.1-77.4) for extracellular volume fraction (ECV), and 50.1 (95% CI: 31.2-68.9) and 60.2 (95% CI: 36.7-79.7) for late gadolinium enhancement (LGE). The areas under the hierarchical modeling–based summary receiver-operating characteristic curve were 0.84 (95% CI: 0.81-0.87) for T1, 0.92 (95% CI: 0.89-94) for T2, 0.78 (95% CI: 0.74-0.81) for ECV, and 0.56 (95% CI: 0.51-0.60) for LGE. T2 values demonstrated the highest diagnostic accuracy, followed by native T1, ECV, and LGE (all P values <0.001 for T1, ECV, and LGE vs T2).ConclusionsT2 mapping demonstrated higher diagnostic accuracy than other CMR techniques. Native T1 and ECV provide high diagnostic use but lower diagnostic accuracy compared with T2, which was related primarily to lower specificity. LGE showed poor diagnostic performance for detection of rejection.     

Prognostic Value of Stress CMR Perfusion Imaging in Patients With Reduced Left Ventricular Function

ObjectivesThe aim of this study was to investigate the prognostic value of stress cardiac magnetic resonance imaging (CMR) in patients with reduced left ventricular (LV) systolic function.BackgroundPatients with ischemic cardiomyopathy are at risk from both myocardial ischemia and heart failure. Invasive testing is often used as the first-line investigation, and there is limited evidence as to whether stress testing can effectively provide risk stratification.MethodsIn this substudy of a multicenter registry from 13 U.S. centers, patients with reduced LV ejection fraction (<50%), referred for stress CMR for suspected myocardial ischemia, were included. The primary outcome was cardiovascular death or nonfatal myocardial infarction. The secondary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, hospitalization for unstable angina or congestive heart failure, and unplanned late coronary artery bypass graft surgery.ResultsAmong 582 patients (mean age 62 ± 12 years, 34% women), 40% had a history of congestive heart failure, and the median LV ejection fraction was 39% (interquartile range: 28% to 45%). At median follow-up of 5.0 years, 97 patients had experienced the primary outcome, and 182 patients had experienced the secondary outcome. Patients with no CMR evidence of ischemia or late gadolinium enhancement (LGE) experienced an annual primary outcome event rate of 1.1%. The presence of ischemia, LGE, or both was associated with higher event rates. In a multivariate model adjusted for clinical covariates, ischemia and LGE were independent predictors of the primary (hazard ratio [HR]: 2.63; 95% confidence interval [CI]: 1.68 to 4.14; p < 0.001; and HR: 1.86; 95% CI: 1.05 to 3.29; p = 0.03) and secondary (HR: 2.14; 95% CI: 1.55 to 2.95; p < 0.001; and HR 1.70; 95% CI: 1.16 to 2.49; p = 0.007) outcomes. The addition of ischemia and LGE led to improved model discrimination for the primary outcome (change in C statistic from 0.715 to 0.765; p = 0.02). The presence and extent of ischemia were associated with higher rates of use of downstream coronary angiography, revascularization, and cost of care spent on ischemia testing.ConclusionsStress CMR was effective in risk-stratifying patients with reduced LV ejection fractions. (Stress CMR Perfusion Imaging in the United States [SPINS] Study; NCT03192891)     

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.     

Myocardial Injury on CMR in Patients With COVID-19 and Suspected Cardiac Involvement

BackgroundMyocardial injury in patients with COVID-19 and suspected cardiac involvement is not well understood.ObjectivesThe purpose of this study was to characterize myocardial injury in a multicenter cohort of patients with COVID-19 and suspected cardiac involvement referred for cardiac magnetic resonance (CMR).MethodsThis retrospective study consisted of 1,047 patients from 18 international sites with polymerase chain reaction–confirmed COVID-19 infection who underwent CMR. Myocardial injury was characterized as acute myocarditis, nonacute/nonischemic, acute ischemic, and nonacute/ischemic patterns on CMR.ResultsIn this cohort, 20.9% of patients had nonischemic injury patterns (acute myocarditis: 7.9%; nonacute/nonischemic: 13.0%), and 6.7% of patients had ischemic injury patterns (acute ischemic: 1.9%; nonacute/ischemic: 4.8%). In a univariate analysis, variables associated with acute myocarditis patterns included chest discomfort (OR: 2.00; 95% CI: 1.17-3.40, P = 0.01), abnormal electrocardiogram (ECG) (OR: 1.90; 95% CI: 1.12-3.23; P = 0.02), natriuretic peptide elevation (OR: 2.99; 95% CI: 1.60-5.58; P = 0.0006), and troponin elevation (OR: 4.21; 95% CI: 2.41-7.36; P < 0.0001). Variables associated with acute ischemic patterns included chest discomfort (OR: 3.14; 95% CI: 1.04-9.49; P = 0.04), abnormal ECG (OR: 4.06; 95% CI: 1.10-14.92; P = 0.04), known coronary disease (OR: 33.30; 95% CI: 4.04-274.53; P = 0.001), hospitalization (OR: 4.98; 95% CI: 1.55-16.05; P = 0.007), natriuretic peptide elevation (OR: 4.19; 95% CI: 1.30-13.51; P = 0.02), and troponin elevation (OR: 25.27; 95% CI: 5.55-115.03; P < 0.0001). In a multivariate analysis, troponin elevation was strongly associated with acute myocarditis patterns (OR: 4.98; 95% CI: 1.76-14.05; P = 0.003).ConclusionsIn this multicenter study of patients with COVID-19 with clinical suspicion for cardiac involvement referred for CMR, nonischemic and ischemic patterns were frequent when cardiac symptoms, ECG abnormalities, and cardiac biomarker elevations were present.     

Long-Term Prognostic Value of Stress CMR in Patients With Heart Failure and Preserved Ejection Fraction

ObjectivesThe objectives of this study were to investigate the long-term prognostic value of inducible myocardial ischemia assessed by vasodilator stress cardiovascular magnetic resonance (CMR) in patients with HFpEF.BackgroundSome studies suggest that ischemia could play a key role in HF in patients with preserved ejection fraction (HFpEF).MethodsBetween 2008 and 2019, consecutive patients prospectively referred for stress CMR with HFpEF as defined by current guidelines, without known coronary artery disease (CAD), were followed for the occurrence of major adverse cardiovascular events (MACE), as defined by cardiovascular mortality or nonfatal myocardial infarction (MI). Secondary composite outcomes included cardiovascular mortality or hospitalization for acute HF. Cox regression analysis was performed to determine the prognostic value of inducible ischemia or late gadolinium enhancement (LGE) by CMR.ResultsAmong the 1,203 patients with HFpEF (73 ± 13 years of age; 29% males) who underwent stress CMR and completed follow-up (6.9 years interquartile range [IQR]: 6.7 to 7.7 years]), 108 experienced a MACE (9%). Kaplan-Meier analysis showed inducible ischemia and LGE were significantly associated with MACE (HR: 6.63; 95% confidence interval [CI]: 4.54 to 9.69; and HR: 2.56; 95% CI: 1.60 to 4.09, respectively; both p < 0.001) and secondary outcomes (HR: 8.40; 95% CI: 6.31 to 11.20; p < 0.001; and HR: 1.87; 95% CI: 1.27 to 2.76, respectively; p = 0.002). In multivariate analysis, inducible ischemia and LGE were independent predictors of MACE (HR: 6.10; 95% CI: 4.14 to 9.00; p < 0.001 and HR: 1.62; 95% CI: 1.06 to 2.49; p = 0.039; respectively).ConclusionsStress CMR-inducible myocardial ischemia and LGE have accurate discriminative long-term prognostic value in HFpEF patients without known CAD to predict the occurrence of MACE.     

Comprehensive Phenotypic Characterization of Late Gadolinium Enhancement Predicts Sudden Cardiac Death in Coronary Artery Disease

BackgroundLate gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) offers the potential to noninvasively characterize the phenotypic substrate for sudden cardiac death (SCD).ObjectivesThe authors assessed the utility of infarct characterization by CMR, including scar microstructure analysis, to predict SCD in patients with coronary artery disease (CAD).MethodsPatients with stable CAD were prospectively recruited into a CMR registry. LGE quantification of core infarction and the peri-infarct zone (PIZ) was performed alongside computational image analysis to extract morphologic and texture scar microstructure features. The primary outcome was SCD or aborted SCD.ResultsOf 437 patients (mean age: 64 years; mean left ventricular ejection fraction [LVEF]: 47%) followed for a median of 6.3 years, 49 patients (11.2%) experienced the primary outcome. On multivariable analysis, PIZ mass and core infarct mass were independently associated with the primary outcome (per gram: HR: 1.07 [95% CI: 1.02-1.12]; P = 0.002 and HR: 1.03 [95% CI: 1.01-1.05]; P = 0.01, respectively), and the addition of both parameters improved discrimination of the model (Harrell’s C-statistic: 0.64-0.79). PIZ mass, however, did not provide incremental prognostic value over core infarct mass based on Harrell’s C-statistic or risk reclassification analysis. Severely reduced LVEF did not predict the primary endpoint after adjustment for scar mass. On scar microstructure analysis, the number of LGE islands in addition to scar transmurality, radiality, interface area, and entropy were all associated with the primary outcome after adjustment for severely reduced LVEF and New York Heart Association functional class of >1. No scar microstructure feature remained associated with the primary endpoint when PIZ mass and core infarct mass were added to the regression models.ConclusionsComprehensive LGE characterization independently predicted SCD risk beyond conventional predictors used in implantable cardioverter-defibrillator (ICD) insertion guidelines. These results signify the potential for a more personalized approach to determining ICD candidacy in CAD.     

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.     

Feasibility and Prognostic Value of Vasodilator Stress Perfusion CMR in Patients With Atrial Fibrillation

ObjectivesThe aim of this study was to assess the feasibility and prognostic value of vasodilator stress perfusion cardiovascular magnetic resonance (CMR) in patients with atrial fibrillation (AF).BackgroundBecause most studies have excluded arrhythmic patients, the prognostic value of stress perfusion CMR in patients with AF is unknown.MethodsBetween 2008 and 2018, consecutive patients with suspected or stable chronic coronary artery disease and AF referred for vasodilator stress perfusion CMR were included and followed for the occurrence of major adverse cardiovascular event(s) (MACE), defined as cardiovascular death or nonfatal myocardial infarction. The diagnosis of AF was defined by 12-lead electrocardiography before and after CMR. Univariate and multivariate Cox regressions were performed to determine the prognostic value of inducible ischemia or late gadolinium enhancement (LGE) by CMR.ResultsOf 639 patients (mean age 72 ± 9 years, 77% men), 602 (94%) completed the CMR protocol, and 538 (89%) completed follow-up (median 5.1 years); 80 had MACE. Using Kaplan-Meier analysis, the presence of ischemia (hazard ratio [HR]: 7.56; 95% confidence interval [CI]: 4.86 to 11.80) or LGE (HR: 2.41; 95% CI: 1.55 to 3.74) was associated with the occurrence of MACE (p < 0.001 for both). In a multivariate Cox regression including clinical and CMR indexes, the presence of ischemia (HR: 5.98; 95% CI: 3.68 to 9.73) or LGE (HR: 2.61; 95% CI: 1.89 to 3.60) was an independent predictor of MACE (p < 0.001 for both).ConclusionsIn patients with AF, stress perfusion CMR is feasible and has good discriminative prognostic value to predict the occurrence of MACE.     

T1 Mapping and Extracellular Volume Fraction in Dilated Cardiomyopathy: A Prognosis Study

ObjectivesThe aim of this study is to examine the prognostic value of T1 mapping and the extracellular volume (ECV) fraction in patients with dilated cardiomyopathy (DCM).BackgroundPatients with DCM with functional left ventricular remodeling have poorer prognoses. Noninvasive assessment of myocardial fibrosis using T1 mapping and the ECV fraction may improve risk stratification of patients with DCM; however, this has not yet been systematically evaluated.MethodsA total of 659 consecutive patients with DCM (498 men; 45 ± 15 years) who underwent cardiac magnetic resonance with T1 mapping and late gadolinium enhancement (LGE) imaging with a 1.5-T magnetic resonance scanner were enrolled in this study. Primary endpoints were cardiac-related death and heart transplantation. Secondary endpoints were hospitalization for heart failure, ventricular arrhythmias, and implantable cardioverter-defibrillator or cardiac resynchronization therapy implantation. Survival estimates were calculated by Kaplan-Meier curves with the log-rank test.ResultsDuring a mean follow-up of 66.3 ± 20.9 months, 122 and 205 patients with DCM reached the primary and secondary endpoints, respectively. The presence of LGE had an association with both of the primary and secondary endpoints observed in the patients with DCM (both P < 0.001). The maximum native T1 (HR: 1.04; 95% CI: 1.02-1.09) and maximum ECV fraction (HR: 1.14; 95% CI: 1.08-1.21) had associations with the primary endpoints in the patients with positive LGE (both P < 0.001), whereas the mean native T1 (HR: 1.13; 95% CI: 1.10-1.36) and mean ECV fraction (HR: 1.32; 95% CI: 1.12-1.53) had the best associations in the patients with negative LGE (all P < 0.001).ConclusionsT1 mapping and the ECV fraction had prognostic value in patients with DCM and were particularly important in patients with DCM without LGE. Using a combination of T1 mapping, ECV fraction, and LGE provided optimal risk stratification for patients with DCM.     

Mitral Regurgitation in Low-Flow,Low-Gradient Aortic Stenosis Patients Undergoing TAVR: Insights From the TOPAS-TAVI Registry

ObjectivesThis study sought to determine the incidence, clinical impact, and changes over time of mitral regurgitation (MR) in patients with low-flow, low-gradient aortic stenosis (LFLG-AS) undergoing transcatheter aortic valve replacement (TAVR).BackgroundFew data exist on the clinical impact and changes in severity over time of MR in patients with LFLG-AS undergoing TAVR.MethodsA total of 308 TAVR candidates with LFLG-AS were included. Patients were categorized according to MR severity at baseline, and presence of MR improvement at 12-month follow-up. Clinical outcomes were assessed at 1 and 12 months (+ echocardiography), and yearly thereafter.ResultsBaseline mild and moderate-to-severe MR were present in 118 (38.3%) and 115 (37.3%) patients, respectively. MR was of functional and mixed etiology in 77.2% and 22.7% of patients, respectively. A total of 131 patients (42.5%) died after a median follow-up of 2 (1 to 3) years. Baseline moderate-or-greater MR had no impact on mortality (hazard ratio [HR]: 1.34; 95% confidence interval [CI]: 0.72 to 2.48) or heart failure hospitalization (HR: 1.02; 95% CI: 0.49 to 2.10). At 1-year follow-up, MR improved in 44.3% of patients and remained unchanged/worsened in 55.7%. The lack of MR improvement was associated with a higher risk of all-cause and cardiac mortality (HR: 2.02; 95% CI: 1.29 to 3.17; HR: 3.03; 95% CI: 1.27 to 7.23, respectively), rehospitalization for cardiac causes (HR: 1.50; 95% CI: 1.04 to 2.15), and an increased overall-mortality/heart failure rehospitalization (HR: 1.94; 95% CI: 1.25 to 3.02). A higher baseline left ventricular end-diastolic diameter and a higher increase in left ventricular ejection fraction were found to be independent predictors of MR improvement at 1-year follow-up (odds ratio: 0.69; 95% CI: 0.51 to 0.94; and odds ratio: 0.81; 95% CI: 0.67 to 0.96, respectively).ConclusionsMost TAVR candidates with LFLG-AS had some degree of MR, of functional origin in most cases. MR improved in about one-half of patients, with larger left ventricular size and a higher increase in left ventricular ejection fraction post-TAVR determining MR improvement over time. The lack of MR improvement at 1 year was associated with poorer outcomes.     

Feature Tracking Myocardial Strain Incrementally Improves Prognostication in Myocarditis Beyond Traditional CMR Imaging Features

ObjectivesThis study investigated the association of cardiovascular cardiac magnetic resonance (CMR) feature tracking (FT) with outcome in a patient cohort with myocarditis and evaluated the possible incremental prognostic benefit beyond clinical features and traditional CMR features.BackgroundCMR is used to diagnose and risk stratify patients with myocarditis. CMR-FT allows quantitative strain analysis of myocardial function; however, its prognostic benefit in myocarditis is unknown.MethodsConsecutive patients with clinically suspected myocarditis and presence of midmyocardial or epicardial late gadolinium enhancement (LGE) and/or myocardial edema in CMR were included. Clinical and CMR features were analyzed with regard to major adverse cardiovascular events (MACE) (i.e., hospitalization for heart failure, sustained ventricular tachycardia, and all-cause mortality).ResultsOf 740 patients with clinically suspected myocarditis, 455 (61%) met our final diagnostic criteria based on CMR tissue characterization. At a median follow-up of 3.9 years, MACE occurred in 74 (16%) patients. In the univariable analysis, CMR-FT global longitudinal peak strain (GLS) was significantly associated with MACE. In a multivariable model adjusting for clinical variables (age, sex, body mass index, and acuteness of symptoms) and traditional CMR features (left ventricular ejection fraction [LVEF] and LGE extent), GLS remained independently associated with outcome (GLS hazard ratio: 1.21; 95% confidence interval: 1.08 to 1.36; p = 0.001) and incrementally improved prognostication (chi-square increases from 42.6 to 79.8 to 88.5; p < 0.001).ConclusionsMyocardial strain using CMR-FT provides independent and incremental prognostic value over clinical features, LVEF, and LGE in patients with myocarditis. CMR-FT may serve as a novel marker to improve risk stratification in myocarditis. (CMR Features in Patients With Suspected Myocarditis [CMRMyo]; NCT03470571)     

Prognostic Value of Stress CMR in Symptomatic Patients With Coronary Stenosis on CCTA

BackgroundNoninvasive functional imaging is often performed in patients with obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CTA). However, the prognostic value of stress cardiac magnetic resonance (CMR) is unknown in patients with coronary stenosis of unknown significance on coronary CTA.ObjectivesThis study assessed the prognostic value of stress CMR in symptomatic patients with obstructive CAD of unknown significance on coronary CTA.MethodsBetween 2008 and 2020, consecutive symptomatic patients without known CAD referred for coronary CTA were screened. Patients with obstructive CAD (at least 1 ≥50% stenosis on coronary CTA) were further referred for stress CMR and followed for the occurrence of major adverse cardiovascular events (MACEs), defined as cardiovascular death or nonfatal myocardial infarction.ResultsOf 2,210 patients who completed CMR, 2,038 (46.5% men; mean age 69.8 ± 12.2 years) completed follow-up (median 6.8 years; IQR: 5.9-9.2 years); 281 experienced a MACE (13.8%). Inducible ischemia and late gadolinium enhancement (LGE) were significantly associated with MACEs (HR: 4.51 [95% CI: 3.55-5.74], and HR: 3.32 [95% CI: 2.55-4.32], respectively; P < 0.001). In multivariable Cox regression, the number of segments with >70% stenosis, with noncalcified plaques and the number of vessels with obstructive CAD were prognosticators (P < 0.001). The presence of inducible ischemia and LGE were independent predictors of MACEs (HR: 3.97 [95% CI: 3.43-5.13]; HR: 2.30 [95% CI: 1.52-3.33]; P < 0.001). After adjustment, stress CMR showed the best improvement in model discrimination and reclassification above traditional risk factors and coronary CTA (C-statistic improvement: 0.04; net reclassification improvement = 0.421; integrative discrimination index = 0.047).ConclusionsIn symptomatic patients with obstructive CAD of unknown significance on coronary CTA, stress CMR had incremental prognostic value to predict MACEs.     

Prognostic Value of Preprocedural LV Global Longitudinal Strain for Post-TAVR-Related Morbidity and Mortality: A Meta-Analysis

BackgroundLeft ventricular ejection fraction (LVEF) demonstrates limited prognostic value for post-transcatheter aortic valve replacement (TAVR) outcomes. Evidence regarding the potential role of left ventricular global longitudinal strain (LV-GLS) in this setting is inconsistent.ObjectivesThe aim of this systematic review and meta-analysis of aggregated data was to evaluate the prognostic value of preprocedural LV-GLS for post–TAVR-related morbidity and mortality.MethodsThe authors searched PubMed, Embase, and Web of Science for studies investigating the association between preprocedural 2-dimensional speckle-tracking–derived LV-GLS and post-TAVR clinical outcomes. An inversely weighted random effects meta-analysis was adopted to investigate the association between LV-GLS vs primary (ie, all-cause mortality) and secondary (ie, major cardiovascular events [MACE]) post-TAVR outcomes.ResultsOf the 1,130 identified records, 12 were eligible, all of which had a low-to-moderate risk of bias (Newcastle-Ottawa scale). On average, 2,049 patients demonstrated preserved LVEF (52.6% ± 1.7%), but impaired LV-GLS (−13.6% ± 0.6%). Patients with a lower LV-GLS had a higher all-cause mortality (pooled HR: 2.01; 95% CI: 1.59-2.55) and MACE (pooled odds ratio [OR]: 1.26; 95% CI: 1.08-1.47) risk compared with patients with higher LV-GLS. In addition, each percentage point decrease of LV-GLS (ie, toward 0%) was associated with an increased mortality (HR: 1.06; 95% CI: 1.04-1.08) and MACE risk (OR: 1.08; 95% CI: 1.01-1.15).ConclusionsPreprocedural LV-GLS was significantly associated with post-TAVR morbidity and mortality. This suggests a potential clinically important role of pre-TAVR evaluation of LV-GLS for risk stratification of patients with severe aortic stenosis. (Prognostic value of left ventricular global longitudinal strain in patients with aortic stenosis undergoing Transcatheter Aortic Valve Implantation: a meta-analysis; CRD42021289626)     

Magnetic Resonance Imaging in Pediatric Myocarditis: Trends and Associations With Cost and Outcome

BackgroundCardiac magnetic resonance (CMR) provides tissue characterization and structural and functional data. CMR has high sensitivity and specificity for myocarditis in adults and children. The relationship between pediatric CMR use, cost, and clinical outcome has not been studied.ObjectivesThis work aims to describe temporal trends in CMR imaging for pediatric myocarditis and examine associations between CMR use, hospital cost, and outcomes.MethodsA retrospective cohort study of all inpatients <21 years of age with a diagnosis of myocarditis reported to the Pediatric Health Information System (2004-2019) was performed. Trends in CMR use were examined. A propensity-matched subcohort using center and patient level variables was used to assess whether outcomes differed by CMR use.ResultsA total of 4,195 children with myocarditis from 47 hospitals were identified. The median age was 11.5 years (IQR: 1.5-16.0 years) and 2,617 (62%) were male. CMR was used in 23% and mortality occurred in 6%. CMR use during hospitalization increased from 2% in 2004 to 37% in 2019 (odds ratio [OR]: 1.19 [95% CI: 1.17-1.21]). After propensity score matching, CMR use was associated with higher median cost (+$5,340 [95% CI: +$1,739 to +$9,936]) and similar median length of stay (0 days [95% CI: ?1 to +1 days]). Using quantile regression, CMR was associated with lower 90th percentile cost (?$77,200 [95% CI: ?$127,373 to ?$31,339]). More children receiving CMR were discharged alive in the first 30 days after admission (OR: 1.89 days [95% CI: 1.28-2.29]). Within the propensity matched cohort, <10 of 790 CMR recipients died compared to 42 of 790 in the non-CMR group.ConclusionsCMR use in children with myocarditis has increased over the past 15 years. CMR use is associated with higher cost of hospitalization and similar length of stay for most children but lower cost among the sickest children. CMR use in specific patients may improve clinical outcomes at a lower cost.     

Incident Clinical and Mortality Associations of Myocardial Native T1 in the UK Biobank

BackgroundCardiac magnetic resonance native T1-mapping provides noninvasive, quantitative, and contrast-free myocardial characterization. However, its predictive value in population cohorts has not been studied.ObjectivesThe associations of native T1 with incident events were evaluated in 42,308 UK Biobank participants over 3.17 ± 1.53 years of prospective follow-up.MethodsNative T1-mapping was performed in 1 midventricular short-axis slice using the Shortened Modified Look-Locker Inversion recovery technique (WIP780B) in 1.5-T scanners (Siemens Healthcare). Global myocardial T1 was calculated using an automated tool. Associations of T1 with: 1) prevalent risk factors (eg, diabetes, hypertension, and high cholesterol); 2) prevalent and incident diseases (eg, any cardiovascular disease [CVD], any brain disease, valvular heart disease, heart failure, nonischemic cardiomyopathies, cardiac arrhythmias, atrial fibrillation [AF], myocardial infarction, ischemic heart disease [IHD], and stroke); and 3) mortality (eg, all-cause, CVD, and IHD) were examined. Results are reported as odds ratios (ORs) or HRs per SD increment of T1 value with 95% CIs and corrected P values, from logistic and Cox proportional hazards regression models.ResultsHigher myocardial T1 was associated with greater odds of a range of prevalent conditions (eg, any CVD, brain disease, heart failure, nonischemic cardiomyopathies, AF, stroke, and diabetes). The strongest relationships were with heart failure (OR: 1.41 [95% CI: 1.26-1.57]; P = 1.60 × 10^-9) and nonischemic cardiomyopathies (OR: 1.40 [95% CI: 1.16-1.66]; P = 2.42 × 10^-4). Native T1 was positively associated with incident AF (HR: 1.25 [95% CI: 1.10-1.43]; P = 9.19 × 10^-4), incident heart failure (HR: 1.47 [95% CI: 1.31-1.65]; P = 4.79 × 10^-11), all-cause mortality (HR: 1.24 [95% CI: 1.12-1.36]; P = 1.51 × 10^-5), CVD mortality (HR: 1.40 [95% CI: 1.14-1.73]; P = 0.0014), and IHD mortality (HR: 1.36 [95% CI: 1.03-1.80]; P = 0.0310).ConclusionsThis large population study demonstrates the utility of myocardial native T1-mapping for disease discrimination and outcome prediction.     

Outcome in Dilated Cardiomyopathy Related to the Extent,Location, and Pattern of Late Gadolinium Enhancement

ObjectivesThis study sought to investigate the association between the extent, location, and pattern of late gadolinium enhancement (LGE) and outcome in a large dilated cardiomyopathy (DCM) cohort.BackgroundThe relationship between LGE and prognosis in DCM is incompletely understood.MethodsThe authors examined the association between LGE and all-cause mortality and a sudden cardiac death (SCD) composite based on the extent, location, and pattern of LGE in DCM.ResultsOf 874 patients (588 men, median age 52 years) followed for a median of 4.9 years, 300 (34.3%) had nonischemic LGE. Estimated adjusted hazard ratios for patients with an LGE extent of 0 to 2.55%, 2.55% to 5.10%, and >5.10%, respectively, were 1.59 (95% confidence interval [CI]: 0.99 to 2.55), 1.56 (95% CI: 0.96 to 2.54), and 2.31 (95% CI: 1.50 to 3.55) for all-cause mortality, and 2.79 (95% CI: 1.42 to 5.49), 3.86 (95% CI: 2.09 to 7.13), and 4.87 (95% CI: 2.78 to 8.53) for the SCD endpoint. There was a marked nonlinear relationship between LGE extent and outcome such that even small amounts of LGE predicted a substantial increase in risk. The presence of septal LGE was associated with increased mortality, but SCD was most associated with the combined presence of septal and free-wall LGE. Predictive models using LGE presence and location were superior to models based on LGE extent or pattern.ConclusionsIn DCM, the presence of septal LGE is associated with a large increase in the risk of death and SCD events, even when the extent is small. SCD risk is greatest with concomitant septal and free-wall LGE. The incremental value of LGE extent beyond small amounts and LGE pattern is limited.     

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.