Septal Late Gadolinium Enhancement Research Articles

Cardiac Magnetic Resonance Imaging as a Risk Stratification Tool in COVID-19 Myocarditis.

The aim of this retrospective study was to identify myocardial injury after COVID-19 inflammation and explore whether myocardial damage could be a possible cause of the persistent symptoms following COVID-19 infection in previously healthy individuals. This study included 139 patients who were enrolled between January and June 2021, with a mean age of 46.7 ± 15.2 years, of whom 68 were men and 71 were women without known cardiac or pulmonary diseases. All patients underwent clinical work-up, laboratory analysis, cardiac ultrasound, and CMR on a 1.5 T scanner using a recommended protocol for morphological and functional assessment before and after contrast media application with multi-parametric sequences. In 39% of patients, late gadolinium enhancement (LGE) was found as a sign of myocarditis. Fibrinogen was statistically significantly higher in patients with LGE than in those without LGE (4.3 ± 0.23 vs. 3.2 ± 0.14 g/L, p < 0.05, respectively), as well as D-dimer (1.8 ± 0.3 vs. 0.8 ± 0.1 mg/L FEU). Also, troponin was statistically significantly higher in patients with myocardial LGE (13.1 ± 0.4 ng/L) compared to those with normal myocardium (4.9 ± 0.3 ng/L, p < 0.001). We demonstrated chest pain, fatigue, and elevated troponin to be independent predictors for LGE. Septal LGE was shown to be a predictor for arrhythmias. The use of CMR is a potential risk stratification tool in evaluating outcomes following COVID-19 myocarditis.

A high-risk late gadolinium enhancement pattern is associated with arrhythmic events in patients with dilated cardiomyopathy

Abstract Introduction Myocardial fibrosis constitutes a substrate for the development of ventricular arrhythmias in patients with non-ischaemic dilated cardiomyopathy (DCM). Late gadolinium enhancement (LGE)-cardiac magnetic resonance (CMR) imaging represents a powerful tool for arrhythmic risk stratification. Moreover, arrhythmic risk is determined by the extent and localization of LGE. A high-risk LGE pattern, defined as the presence of epicardial, transmural or septal plus free-wall LGE, has been recently associated with a higher incidence of arrhythmic events comparing with other LGE patterns. Purpose To evaluate the prevalence of a high-risk LGE pattern in patients with DCM and its association with arrhythmic events. Methods From 2014 to 2021, all patients (N = 229) with DCM were prospectively evaluated in our tertiary care hospital. 174 patients underwent a 1.5 Tesla scanner CMR as part of the diagnostic workup and were included in the present study. The primary endpoint was a composite of sudden cardiac death or sustained monomorphic ventricular tachycardia. Results Mean age of our cohort was 61 years (standard deviation 14.5), and 64.2% were male. Median follow-up was 41 (interquartile range 26-62) months. LGE was present in 96 (55.2%) patients of our cohort (LGE+), and a high risk LGE pattern was found in 41 (42.7% of all LGE+ patients). LGE was more frequently located in the basal segments (78.6%). Mid-wall septal LGE was found in 46.9% of LGE+ patients, and it was the most common pattern. 21.4% of LGE+ patients had combined septal and free-wall LGE, 23.5% had epicardial LGE and 13.3% had transmural LGE. Baseline characteristics of LGE+ patients with and without a high-risk LGE pattern are shown at the Table. The incidence of ventricular arrhythmic events during follow-up was 31.7% in patients with a high-risk LGE pattern, and 9.1% in LGE+ patients but without a high-risk pattern (p=0.005). In patients without a high-risk LGE, including LGE- patients and LGE+ patients with other LGE patterns, incidence of ventricular arrhythmic events was 8.3% (p&amp;lt;0.001). The survival free curves for the combined arrhythmic endpoint comparing LGE+ patients with and without a high-risk pattern are shown in the Figure. Conclusion The presence of a high-risk LGE pattern in patients with DCM its associated with a higher incidence of ventricular arrhythmic events, comparing with LGE+ patients without a high-risk pattern. We suggest that this high-risk pattern should be taken into account when performing arrhythmic risk stratification in patients with DCM.TableFigure

Prognostic impact of the extent, location, and pattern of late gadolinium enhancement in dilated cardiomyopathy

Abstract Background Several studies have shown that the presence and extent of late gadolinium enhancement (LGE) defined by cardiac magnetic resonance imaging (CMR) are strong prognosticators of death in patients with dilated cardiomyopathy (DCM). The interest of LGE location and pattern to improve risk stratification is not well established. Purpose To assess the incremental prognostic value of LGE extent, location and pattern for predicting all-cause death over traditional risk factors in DCM patients. Methods Between 2008 and 2021, we conducted a bi-centre longitudinal study including all consecutive DCM patients referred for CMR. DCM was confirmed excluding patients with ischemic heart disease, history of acute myocarditis, hypertrophic cardiomyopathy, and infiltrative disease. The outcome was all-cause death using the electronic French National Registry of Death. The prognostic value of LGE parameters was assessed using Cox analyses after adjustment for traditional prognostic factors: LGE presence, extent (number of segments), pattern (midwall or subepicardial), location and multiple areas. The incremental prognostic value of these LGE parameters was assessed using C-statistic increment, the continuous net reclassification improvement (NRI), the integrative discrimination index (IDI) and the global Chi-2. Results In 2,752 DCM patients (52±8 years, 56% male), 408 (15%) died after a median (IQR) follow-up of 9.2 (6.8-11.5) years. A total of 737 (27%) patients had LGE, including 664 (90%) LGE mid-wall and 73 (10%) LGE sub-epicardial. In the whole cohort (n=2,752), the LGE presence and extent were strong predictors of death (HR: 2.42 [95% CI: 1.67-3.51] and HR: 1.78 [95% CI: 1.64-1.93]; both p&amp;lt;0.001). In the subgroup of patients with LGE (n=737), the LGE multiple area was an independent predictor of death (HR: 5.12 with 95% CI: 3.53-7.41; p&amp;lt;0.001). The LGE pattern wasn't associated with death (subepicardial: HR: 0.88; 95% CI: 0.56-1.39, p=0.58). The location in both septal and free-wall was strongly associated with death compared to septal LGE only (HR: 10.1; 95% CI: 7.53-13.6; p&amp;lt;0.001), itself more at risk of death than free-wall LGE only (HR: 3.12; 95% CI: 2.03-4.78; p&amp;lt;0.001). In the 537 patients with LGE single area, LGE in septal segments was a strong prognostic marker (HR: 17.0; 95% CI: 5.88-49.4; p&amp;lt;0.001) compared to other locations (inferior: HR: 10.3; 95% CI: 3.45-30.5; p&amp;lt;0.001; lateral: HR: 6.13; 95% CI: 1.95-19.2; p&amp;lt;0.01; reference=anterior). A model combining the LGE extent, location and multiple area showed the best improvement in model discrimination and reclassification above traditional risk factors (C-statistic improvement: 0.19; NRI=11.8%; IDI=2.2%, all p&amp;lt;0.001). Conclusion In a large cohort of DCM patients, the LGE extent, location, and multiple area were independent prognosticators of death. A model combining these LGE findings had an incremental prognostic value over traditional prognostic factors to predict all-cause death.Incremental prognostic value of LGEHazard ratios regarding LGE segments

Abstract 12377: Differing Response to Left Bundle Branch Area Pacing versus Biventricular Pacing for Cardiac Resynchronization According to Septal Scar Burden Among Nonischemic Cardiomyopathy Patients

Introduction: Whether left bundle branch area pacing (LBBAP) have similar benefit compared with biventricular pacing (BVP) for cardiac resynchronization therapy (CRT) in nonischemic cardiomyopathy (NICM) with different septal scar burden is still unknown. Hypothesis: We hypothesize that a higher septal scar burden might attenuate the relative benefits of LBBAP versus BVP. Aims: This study aims to assess the effect of the septal scar on the response to LBBAP and BVP for CRT. Methods: We retrospectively included nonischemic cardiomyopathy (NICM) patients with wide QRS complex and CRT indications who underwent pre-procedure cardiac magnetic resonance (CMR) examination and received either BVP or LBBAP. Late gadolinium enhancement (LGE) was analyzed for scar quantification. CRT response was defined as an absolute increase of≥ 5% in left ventricular ejection fraction (LVEF) at 6 months follow-up. Results: A total of 147 patients were included. Fifty-one patients (34.7%) had LBBAP, and 96 (65.3%) had BVP. As septal LGE extent increased, LVEF improvement at 6-month follow-up gradually decreased in the BVP group whereas dropped sharply in the LBBAP group. The nonlinear inverse relationship between the relative benefit of LBBAP versus BVP for response and septal LGE extent, as well as cut-off points (4.4%, 13.3%) of septal LGE extent, were determined using a restricted cubic spline model. Among patients with low septal scar extent (&lt;4.4%), LBBAP was associated with higher response odds than BVP [Odds Ratio (OR) 3.87,95% confidence interval (CI): 0.99-15.17,p=0.052]. In the medium septal scar extent (4.4%-13.3%) group, response odds did not differ between LBBAP and BVP (OR 2.00,95%CI: 0.41-9.74, p=0.391). Among patients with high septal scar extent (&gt;13.3%), BVP was associated with higher response odds (OR 0.12, 95%CI: 0.03-0.54, p=0.006). Conclusions: Response to LBBAP and BVP among NICM patients might be impacted by septal scar burden.

Cardiac Magnetic Resonance in Patients with Suspected Tachycardia-Induced Cardiomyopathy: The Impact of Late Gadolinium Enhancement and Epicardial Fat Tissue.

Tachycardia-induced cardiomyopathy (TIC) is a reversible subtype of dilated cardiomyopathy (DCM) resulting from sustained supraventricular or ventricular tachycardia and diagnosed by the normalization of left ventricular ejection fraction (LVEF) after stable sinus rhythm restoration. The aim of this study was to determine the contribution of cardiac magnetic resonance (CMR) to the differential diagnosis of TIC and DCM with persistent atrial arrythmias in patients hospitalized for the first time with heart failure (HF) with reduced LVEF of nonischemic origin. A total of 29 patients (age: 58.2 ± 16.9 years; males: 65.5%; average EF: 37.0 ± 9.5%) with persistent atrial tachyarrhythmia and first decompensation of HF without known coronary artery diseases were included in this study. The patients successfully underwent cardioversion and were observed for 30 days. The study population was divided into groups of responders (TIC patients; N = 16), which implies achieving FF > 50% or its increase > 10% in 30 days of TIC, and non-responders (N = 13). The increase in left ventricle (LV) volumes measured using CMR was significantly higher in the non-responder group when compared with the responders (114.8 mL ± 25.1 vs. 68.1 mL ± 10.5, respectively, p < 0.05). Non-responders also demonstrated decreased interventricular septum thickness (9.1 ± 0.8 vs.11.5 ± 1.3, respectively, p < 0.05). Late gadolinium enhancement (LGE) was observed in 12 patients (41.4%). The prevalence of LGE was increased in the non-responder group (25.0% vs. 65.1%, respectively, p = 0.046). Notably, a septal mid-wall LGE pattern was found exclusively in the non-responders. Epicardial adipose tissue thickness was decreased in the non-responder group versus the TIC patients. Conclusion: Patients with TIC were found to have smaller atrial and ventricular dimensions in comparison to patients with DCM. In addition, LGE was more common in DCM patients.

Effect of late gadolinium enhancement on left atrial impairment in myocarditis patients

ObjectiveThe aims of our study were to investigate the effect of the extent and location of late gadolinium enhancement (LGE) on the left atrium (LA) function in patients with acute myocarditis (AM) using cardiovascular magnetic resonance (CMR).MethodThis retrospective study performed CMR scans in 113 consecutive patients (89 males, 24 females; mean age 45.8 ± 17.3 years) with AM that met the updated Lake Louise criteria. Reservoir, conduit, and booster LA functions were analyzed by CMR feature tracking using dedicated software. Besides LA strain measurements, myocardial scar location and extent were assigned and quantified by LGE imaging.ResultsAM patients with septal LGE had impaired reservoir, conduit, and conduit strain rate function in comparison with AM patients with non-septal LGE (p = 0.001, for all). In fully adjusted multivariable linear regression, reservoir and conduit were significantly associated with left ventricle (LV) LGE location (β coefficient = 8.205, p = 0.007; β coefficient = 5.185, p = 0.026; respectively). In addition, LA parameters decreased according to the increase in the extent of LV fibrosis (LGE ≤ 10%; LGE 11–19%; LGE ≥ 20%). After adjustment in multivariable linear regression, the association with LV LGE extent was no longer statistically significant.ConclusionIn patients with acute myocarditis, LA function abnormalities are significantly associated with LV LGE location, but not with LGE extent. Septal LGE is paralleled by a deterioration of LA reservoir and conduit function.Clinical relevance statementLeft atrium dysfunction is associated with the presence of late gadolinium enhancement in the left ventricle septum and can be useful in the clinical prognostication of patients with acute myocarditis, allowing individually tailored treatment.Key Points• Myocardial fibrosis is related to atrial impairment.• The location of myocardial fibrosis is the main determinant of atrial dysfunction in myocarditis patients.• The quantification of atrial mechanisms may provide more in-depth insight into myocarditis pathophysiology.

Septal scar as a barrier to left bundle branch area pacing.

The use of left bundle branch area pacing (LBBAP) for bradycardia pacing and cardiac resynchronization is increasing, but implants are not always successful. We prospectively studied consecutive patients to determine whether septal scar contributes to implant failure. Patients scheduled for bradycardia pacing or cardiac resynchronization therapy were prospectively enrolled. Recruited patients underwent preprocedural scar assessment by cardiac MRI with late gadolinium enhancement imaging. LBBAP was attempted using a lumenless lead (Medtronic 3830) via a transeptal approach. Thirty-five patients were recruited: 29 male, mean age 68years, 10 ischemic, and 16 non-ischemic cardiomyopathy. Pacing indication was bradycardia in 26% and cardiac resynchronization in 74%. The lead was successfully deployed to the left ventricular septum in 30/35 (86%) and unsuccessful in the remaining 5/35 (14%). Septal late gadolinium enhancement was significantly less extensive in patients where left septal lead deployment was successful, compared those where it was unsuccessful (median 8%, IQR 2%-18% vs. median 54%, IQR 53%-57%, p<.001). The presence of septal scar appears to make it more challenging to deploy a lead to the left ventricular septum via the transeptal route. Additional implant tools or alternative approaches may be required in patients with extensive septal scar.

Sex-based differences in late gadolinium enhancement among patients with acute myocarditis

ObjectiveThe aims of our study were to investigate the sex differences in late gadolinium enhancement (LGE) using cardiovascular magnetic resonance (CMR) in a single-centre cohort of consecutive patients with acute myocarditis (AM). MethodThis retrospective study performed CMR scans in 135 consecutive patients with AM that met the Lake Louise criteria. On CMR, LV ventricular strain functions were performed on conventional cine SSFP sequences. Besides myocardial strain measurements, myocardial scar location, extension, and size were assigned and quantified by LGE imaging. ResultsThere was no difference in age (age 42.51 ± 19.64 years vs 40.92 ± 19.94 years; p = 0.74) and cardiovascular risk profile between women and men. Despite similar comorbidities, women were more like to present with dyspnea (p = 0.001). Women demonstrated higher prevalence of septal LGE (p = 0.004) and increased global circumferential strain parameters (p = 0.008) in comparison with men. In multivariate analysis, female sex remained an independent determinant of septal LGE (β coefficient = −0.520, p = 0.001). ConclusionThis is the first study reporting sex differences in LGE localization in AM. Women have more septal LGE involvement independent of age, cardiovascular risk factors, and CMR parameters. These findings further emphasize the sex-based differences in cardiovascular diseases.

Septal Midwall Late Gadolinium Enhancement in Ischemic Cardiomyopathy and Nonischemic Dilated Cardiomyopathy—Characteristics and Prognosis

Septal midwall late gadolinium enhancement (LGE) is a characteristic finding on cardiac magnetic resonance imaging (CMR) in nonischemic dilated cardiomyopathy (DCM) and is associated with adverse events. Its significance in ischemic cardiomyopathy (ICM) is unknown. With this multicenter observational study, we aimed to study the characteristics of septal midwall LGE and evaluate its prognostic value in ICM. A total of 1,084 patients with an impaired left ventricular (LV) ejection fraction (<50%) on LGE-CMR, either because of ICM (53%) or DCM, were included retrospectively. Septal midwall LGE was defined as midmyocardial stripe-like or patchy LGE in septal segments and was present in 10% of patients with ICM compared with 34% of patients with DCM (p<0.001). It was significantly associated with larger LV volumes and lower LV ejection fraction, irrespective of etiology. The primary endpoint was all-cause mortality and secondary endpoint was ventricular arrhythmias (VAs), including resuscitated cardiac arrest, sustained VA, and appropriate implantable cardioverter-defibrillator (ICD) therapy. During a median follow-up of 2.7years, we found a significant association between septal midwall LGE and mortality in patients with DCM (hazard ratio [HR] 1.92, p=0.03), but not in patients with ICM (HR 1.35, p=0.39). Risk of VAs was significantly higher in patients with septal midwall LGE on CMR, both in DCM (HR 2.80, p<0.01) and in ICM (HR 2.70, p<0.01). In conclusion, septal midwall LGE, typically seen in DCM, was also present in 10% of patients with ICM and was associated with increased LV dilation and worse function, irrespective of etiology. When present, septal midwall LGE was associated with adverse outcome.

1070 PROGNOSTIC PERFORMANCE OF CARDIAC MAGNETIC RESONANCE IMAGING MARKERS VERSUS COMPLICATED CLINICAL PRESENTATION AFTER AN ACUTE MYOCARDITIS

Abstract Background Identifying markers associated with adverse events after acute myocarditis (AM) is clinically relevant to plan follow-up. We aimed to compare the prognostic performance of previously described cardiac magnetic resonance imaging (CMRI) markers: septal late gadolinium enhancement (LGE) localization and left ventricular ejection fraction (LVEF)&amp;lt;50% on baseline CMRI, versus complicated clinical presentation (CCP) of AM (defined as the presence of sustained ventricular arrhythmias or LVEF &amp;lt;50% on the first echocardiogram or fulminant presentation). Methods We retrospectively assessed 248 AM patients from 6 hospitals with onset of cardiac symptoms &amp;lt;30 days, increased troponin, and CMRI consistent with myocarditis. Results Patients had a median age of 34 years (male prevalence of 87.1%) and a median LVEF of 61% on baseline CMRI. Thirteen patients (5.2%) experienced at least one major cardiac event after a median follow-up of 1708 days. Among these 13 patients, 10 (76.9%) had septal LGE, 8 (61.5%) had LVEF&amp;lt;50%, and 12 (92.3%) had a CCP. The best performance was observed for CCP in terms of sensitivity (0.99), and for LVEF&amp;lt;50% in terms of specificity (0.90). The negative predictive value was at least 0.98 for all markers. Conclusions Major cardiac events after an AM are relatively low, and septal LGE, LVEF&amp;lt;50% on CMRI, and CCP are significantly associated with events. The most relevant finding is the high NPV of these markers to identify patients without events after an AM. This observation can help clinicians to monitor the patients after an AM, in fact, patients without these markers had an uneventful follow-up. Figure A] Acute Myocarditis with complicated clinical presentation (CCP AM) vs non-complicated clinical presentation (NO CCP AM); B] FE &amp;gt; 50% vs FE &amp;lt; 50% at basal cardiac MRI; C] Presence of septal late gadolinium enhancemnet (LGE) vs no septal LGE on basal cardiac MRI.

Septal myocardial scar burden predicts the response to cardiac contractility modulation in patients with heart failure

We hypothesized that myocardial septal scarring, assessed by cardiac magnetic resonance (CMR) using late gadolinium enhancement (LGE), at the site of cardiac contractility modulation (CCM) lead placement may predict treatment response. Eligible heart failure (HF) patients underwent LGE CMR imaging before CCM device implantation. The response to CCM therapy at follow-up was determined by a change in NYHA class and echocardiographic left ventricular ejection fraction (LVEF) assessment. Patients were classified as responders, if they showed an improvement in either NYHA class or improvement of LVEF by ≥ 5%. 58 patients were included. 67% of patients were classified as responders according to improved NYHA; 55% according to LVEF improvement. 74% of patients were responders if either NYHA class or LVEF improvement was observed. 90% of responders (according to NYHA class) showed septal LGE < 25% at septal position of the leads, while 44% of non-responders showed septal LGE > 25% (p < 0.01). In patients treated with CCM, an improvement of NYHA class was observed when leads were placed at myocardial segments with a CMR- LGE burden less than 25%.

Impact of late gadolinium enhancement extent, location, and pattern on ventricular tachycardia and major adverse cardiac events in patients with ischemic vs. non-ischemic cardiomyopathy.

Left ventricular late gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR) has been associated with increased risk for life-threatening ventricular tachyarrhythmias. The differences in association between LGE characteristics and prognosis in patients with ischemic (ICM) vs. non-ischemic (NICM) cardiomyopathy is incompletely understood. A total of 168 consecutive patients who underwent CMR imaging with either ICM or NICM were included in our study. LGE extent, location and pattern were examined for association to the primary endpoint of ventricular tachycardia (VT) and secondary endpoint of major adverse cardiac events (MACE). Of 68 (41%) patients with ICM and 97 (59%) patients with NICM, median LGE mass was 15% (IQR 9-28) for the ICM group and 10% (IQR 6-15) for the NICM group. On multivariate analysis for both groups, LGE characteristics were prognostic while LVEF was not. In patients with ICM, septal and apical segment LGE, and involvement of multiple walls predicted both endpoints on multivariate analysis. LGE extent (≥median) and inferior wall LGE independently predicted the primary endpoint. In patients with NICM, anterior, inferior and apical segment LGE, and involvement of multiple walls predicted both endpoints on multivariate analysis. LGE extent (≥median, number of LGE segments, LGE stratified per 5% increase) and midwall LGE were independent predictors of the primary endpoint. Although LGE was an independent predictor of prognosis in both groups, LGE extent, location, and pattern characteristics were more powerful correlates to worse outcomes in patients with NICM than ICM.

Potential clinical relevance of cardiac magnetic resonance to diagnose cardiac light chain amyloidosis.

While patients with cardiac transthyretin amyloidosis are easily diagnosed with bone scintigraphy, the detection of cardiac light chain (AL) amyloidosis is challenging. Cardiac magnetic resonance (CMR) analyses play an essential role in the differential diagnosis of cardiomyopathies; however, limited data are available from cardiac AL-Amyloidosis. Hence, the purpose of the present study was to analyze the potential role of CMR in the detection of cardiac AL-amyloidosis. We included 35 patients with proved cardiac AL-amyloidosis and two control groups constituted by 330 patients with hypertrophic cardiomyopathy (HCM) and 70 patients with arterial hypertension (HT), who underwent CMR examination. The phenotype and degree of left ventricular (LV) hypertrophy and the amount and pattern of late gadolinium enhancement (LGE) were evaluated. In addition, global and regional LV strain parameters were also analyzed using feature-tracking techniques. Sensitivity and specificity of several CMR parameters were analyzed in diagnosing cardiac AL-amyloidosis. The sensitivity and specificity of diffuse septal subendocardial LGE in diagnosing cardiac AL-amyloidosis was 88% and 100%, respectively. Likewise, the sensitivity and specificity of septal myocardial nulling prior to blood pool was 71% and 100%, respectively. In addition, a LV end-diastolic septal wall thickness ≥ 15 mm had an optimal diagnostic performance to differentiate cardiac AL-amyloidosis from HT (sensitivity 91%, specificity 89%). On the other hand, a reduced global LV longitudinal strain (< 15%) plus apical sparing (apex-to-base longitudinal strain > 2) had a very low sensitivity (6%) in detecting AL-Amyloidosis, but with very high specificity (100%). The findings from this study suggest that CMR could have an optimal diagnostic performance in the diagnosis of cardiac AL-amyloidosis. Hence, further larger studies are warranted to validate the findings from this study.

Cardiac MRI Features and Prognostic Value in Immune Checkpoint Inhibitor-induced Myocarditis.

Background Cardiac MRI features are not well-defined in immune checkpoint inhibitor (ICI)-induced myocarditis (ICI-M), a severe complication of ICI therapy in patients with cancer. Purpose To analyze the cardiac MRI features of ICI-M and to explore their prognostic value in major adverse cardiovascular events (MACE). Materials and Methods In this retrospective study from May 2017 to January 2020, cardiac MRI findings (including late gadolinium enhancement [LGE], T1 and T2 mapping, and extracellular volume fraction [ECV] z scores) of patients with ICI-M were compared with those of patients with cancer scheduled to receive ICI therapy (pre-ICI group) and patients with viral myocarditis. As a secondary objective, the potential value of cardiac MRI for predicting MACE in patients with ICI-M by using Cox proportional hazards models was explored. Results Thirty-three patients with ICI-M (mean age ± standard deviation, 68 years ± 14; 23 men) were compared with 21 patients scheduled to receive to ICI therapy (mean age, 65 years ± 14; 14 men) and 85 patients with viral myocarditis (mean age, 32 years ± 13; 67 men). Compared with the pre-ICI group, patients with ICI-M showed higher global native T1, ECV, and T2 z scores (0.03 ± 0.85 vs 1.79 ± 1.93 [P < .001]; 1.34 ± 0.57 vs 2.59 ± 1.97 [P = .03]; and -0.76 ± 1.41 vs 0.88 ± 1.96 [P = .002], respectively), and LGE was more frequently observed (27 of 33 patients [82%] vs two of 21 [10%]; P < .001). LGE was less frequent in patients with ICI-M than those with viral myocarditis (27 of 33 patients [82%] vs 85 of 85 [100%]; P < .001) but was more likely to involve the septal segments (16 of 33 patients [48%] vs 25 of 85 [29%]; P < .001) and midwall layer (11 of 33 patients [33%] vs two of 85 [2%]; P < .001). Septal LGE was the only cardiac MRI predictor of MACE at 1 year even after adjustment for peak troponin (adjusted hazard ratio, 2.7 [95% CI: 1.1, 6.7]; P = .03). Conclusion Cardiac MRI features of immune checkpoint inhibitor (ICI)-induced myocarditis (ICI-M) seem to differ from those in patients scheduled to receive ICIs and patients with viral myocarditis. Septal late gadolinium enhancement might be a predictor of major cardiovascular events in patients with ICI-M. Clinical trial registration no. NCT03313544 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Edelman and Pursnani in this issue.

Combined assessment of septal scar and septal flash by cardiac magnetic resonance identifies responders to cardiac resynchronization therapy

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): South-Eastern Norway Regional Health Authority. Research grants of the University of Leuven. Background Left ventricular (LV) scar, particularly in the lateral wall and septum, reduces response rate to cardiac resynchronization therapy (CRT), whereas a dyssynchronous LV contraction pattern (septal flash) suggests good response. Lateral wall scar abolishes septal flash. Therefore, a combined approach of septal scar and septal flash may characterize the myocardial substrate responsive to CRT. Cardiac magnetic resonance (CMR) may assess both scar and contraction pattern. Purpose The present study aimed to determine if combined assessment of septal scar and septal flash by CMR as single image modality identifies responders to CRT. Methods We investigated all CRT recipients with available CMR from a prospective, multicenter study (n = 136), with both ischemic and non-ischemic heart failure. Septal scar was assessed by late gadolinium enhancement (LGE) from a stack of short axis slices (n = 128) and septal flash determined visually on ordinary cine sequences (n = 136). CRT response was defined as ≥15% reduction in LV end-systolic volume by echocardiography at 6 months follow-up. We also assessed heart transplantation or death of any cause 39 ± 13 months after device implantation. Results In multivariate analysis including percentage septal scar (LGE), septal flash, QRS-duration and QRS-morphology, septal LGE and septal flash were the only independent predictors of CRT response (both p &amp;lt; 0.001). A combined approach of septal LGE and septal flash predicted CRT response with area under the curve 0.86 (95% confidence interval (CI): 0.78-0.94) and long-term survival without heart transplantation with hazard ratio 0.18 (95% CI: 0.05-0.61). A practical approach to selection of CRT candidates by septal LGE and septal flash is illustrated in the present figure. As shown, absence of septal LGE indicated excellent response rate (93%) to CRT independent of other parameters. When septal LGE was present, however, overall response rate was substantially lower (58%), but presence or absence of septal flash separated responders from non-responders with high accuracy. This sequential approach correctly classified 86% of patients. Importantly, the approach was equally accurate in patients with intermediate QRS duration (130-150ms), where 93% of patients were correctly classified. Conclusions Combined assessment of septal LGE and septal flash by CMR as single image modality identifies CRT responders with high accuracy and predicts long-term survival. Abstract Figure.

Hybrid CMR- and FDG-PET-Imaging Gives New Insights Into the Relationship of Myocardial Metabolic Activity and Fibrosis in Patients With Becker Muscular Dystrophy.

BackgroundCardiac involvement in patients with Becker muscular dystrophy (BMD) is an important predictor of mortality. The cardiac phenotype of BMD patients is characterized by slowly progressive myocardial fibrosis that starts in the left ventricular (LV) free wall segments and extends into the septal wall during the disease course.PurposeSince the reason for this characteristic cardiac phenotype is unknown and comprehensive approaches using e.g. hybrid imaging combining cardiovascular magnetic resonance (CMR) with 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) are limited, the present study addressed this issue by a comprehensive non-invasive imaging approach.MethodsHybrid CMR- and FDG-PET-imaging was performed in N = 14 patients with BMD on a whole-body Biograph mMR system (Siemens, Erlangen, Germany). The CMR protocol comprised cine- and late-gadolinium-enhancement (LGE)-imaging. Metabolism was assessed with FDG-PET after oral glucose loading to effect myocardial carbohydrate uptake. PET was acquired for 65 min starting with tracer injection. Uptake values from 60 to 65 min p.i. were divided by the area under the blood activity curve and reported as percentages relative to the segment with maximal myocardial FDG uptake.ResultsA characteristic pattern of LGE in the LV lateral wall was observed in 13/14 patients whereas an additional septal LGE pattern was documented in 6/14 patients only. There was one patient without any LGE. Segmental FDG uptake was 88 ± 6% in the LV lateral wall vs. 77 ± 10% in the septal wall (p < 0.001). There was an inverse relationship between segmental FDG activity compared to segmental LGE extent (r = −0.33, p = 0.089). There were N = 6 LGE-positive patients with a segmental difference in FDG uptake of >15% in the LV lateral wall compared to the septal wall = ΔFDG-high group (lateral FDG = 91±3% vs. septal FDG = 69±8%; p < 0.001) while the remaining N = 7 LGE-positive patients showed a segmental difference in FDG uptake of ≤ 15% = ΔFDG-low group (lateral FDG = 85±7% vs. septal FDG = 83 ± 5%; p = 0.37). Patients in the ΔFDG-high group showed only a minor difference in the LGE extent between the LV lateral wall vs. septal wall (p = 0.09) whereas large differences were observed in the ΔFDG-low group (p < 0.004).ConclusionsSegmental FDG uptake—reflecting myocardial metabolic activity—is higher in the LV free wall of BMD patients—possibly due to a higher segmental work load. However, segmental metabolic activity seems to be dependent on and limited by the respective segmental extent of myocardial fibrosis as depicted by LGE-imaging.

Abstract 12851: Prognostic Value Of Late Gadolinium Enhancement In Patients With Idiopathic Dilated Cardiomyopathy

Introduction: The aim of this study was to investigate the association between the extent and pattern of late gadolinium enhancement (LGE) and outcomes in a large idiopathic dilated cardiomyopathy (DCM) cohort Hypothesis: LGE is associated with worse outcomes in patient with idiopathic dilated cardiomyopathy Methods: In this study, we retrospectively identified all patients with idiopathic DCM who underwent cardiac MRI (CMR) from 2015 to 2020 at a single large academic center. The association between the pattern of LGE and event free survival from transplantation and mechanical circulatory support was analyzed using Kaplan Meier analysis and the log-rank test. Results: Of a total of 286 patients (64% male, 62% Caucasian) with idiopathic DCM who underwent CMR, LGE was detected in 59 (21%) patients. Of the patients with LGE, 7 (3%) patients had free-wall LGE, 40 (14%) had septal LGE and 12 (4%) had both septal and free wall LGE. All patients had linear mid-wall LGE and two patients had both linear-mid wall and sub-epicardial involvement. The presence of septal LGE was associated with older age (58 ± 12 vs 47 ± 16 years, p&lt;0.001), a lower LV ejection fraction (EF) (30% ± 12 vs 37% ± 12, p&lt;0.001), higher LV end-diastolic volume index (146 ± 47 vs 126 ± 36 ml/m 2 , p&lt;0.001), lower right ventricular EF (37% ± 13 vs 42% ± 13, p=0.013), higher LV mass index (82 ± 25 vs 73 ± 24 g/m 2 , p=0.013), higher incidence of LBBB (29% ± 16 vs 16% ± 29) and atrial fibrillation (31% vs 17%, p=0.021). Over a mean follow-up time of 26 ± 19 months, patients with septal LGE were less likely to experience event free survival from heart transplant or durable mechanical circulatory support (Figure 1, p=0.009). Conclusions: The presence of septal LGE in this large idiopathic DCM cohort is associated with worse outcomes. Additional research is needed to determine whether these findings will aid clinical management of these patients.

Coronary artery branch misinterpreted as pathological septal late gadolinium enhancement: a common pitfall during evaluation of athletes with ventricular arrhythmias.

Cardiac magnetic resonance (CMR) is increasingly prescribed in sport cardiology during pre-participation screening. Common indications are electrocardiography abnormalities, rhythm disturbances, cardiovascular symptoms like syncope, family history for hereditary cardiomyopathy or sudden death, which are all conditions that increase the likelihood of underlying cardiac disease at risk of arrhythmic events with exercise. However, despite its unique capability of tissue characterization and accurate thickness, volume, and function estimation, CMR can be prone to false-positive findings, especially during late gadolinium enhancement (LGE) assessment, leading to cardiac disease overdiagnosis and inappropriate disqualification from competitive sports activity. Herein, we report the case of a 45-year-old male middle distance runner, who came to our attention for frequent premature ventricular beats. Arrhythmias had a prevalent right bundle branch morphology and showed a mild worsening in amount and complexity during effort. Echocardiogram was unremarkable. Conversely, the CMR post-contrast images detected a mid-wall hyperintense signal on basal interventricular septum,...

Cardiac magnetic resonance in athletes with ventricular arrhythmias

Abstract Funding Acknowledgements Type of funding sources: None. Background Ventricular arrhythmias in athletes represent an important issue in sport eligibility as they may be a marker of a concealed cardiomyopathy, potentially at risk of sudden cardiac death during sport activity. Purpose to assess the utility of cardiac magnetic resonance (CMR) to identify cardiac abnormalities in athletes with documented frequent premature ventricular beats (PVB) or complex ventricular arrhythmias (VA) undergoing competitive sport eligibility screening. Methods We enrolled 65 athletes with documented ventricular arrhythmias as follows: 1) frequent PVB at 24-hour ambulatory ECG monitoring (&amp;gt;100 PVB/24h); 2) polymorphic PVB; 3) repetitive PVB (couplets, triplets, or nonsustained ventricular tachicardia). All athletes were studied with rest ECG, exercise stress testing, 24-hour ambulatory ECG monitoring, transthoracic echocardiography and contrast-enhanced CMR. Results Sixty-five athletes (56 males, 9 females, age 30 ± 15years) underwent CMR with gadolinium contrast. In 55 patients (84.6%) CMR was normal, in 10 patients (15.4%) the following abnormalities were reported at CMR: four patients with isolated late gadolinium enhancement (LGE) of whom 3 patients with subepicardial LGE in the inferolateral wall and 1 patient with intramyocardial basal inferior LGE; 1 patient with hypertrophic cardiomyopathy with septal LGE; 1 patient with left ventricular non compaction; 3 patients with right ventricular abnormalities (a 13-year-old patient with dilated right ventricle and LGE located at the superior interventricular insertion point, 1 patient with a dilated and hypokinetic right ventricle, 1 patient with a focal right ventricular aneurysm). Transthoracic echocardiography was normal in 7/10 (70%) athletes with CMR abnormalities. Conclusion In athletes with frequent or complex ventricular arrhythmias cardiac magnetic resonance identifies cardiac abnormalities in a significant proportion of subjects and it may offer a diagnostic incremental value.

Septal late gadolinium enhancement on Cardiac MRI predicts failure to achieve left bundle pacing

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Background; Left bundle area pacing is a novel technique that provides direct stimulation of cardiac conduction tissue in order to deliver physiological ventricular activation. The approach for left bundle area pacing is transseptal lead implantation, where the lead is advanced from the right ventricular side of the septum to the left ventricular side to capture the proximal left bundle. Observational data suggests that whilst this is a safe and feasible method, implant success rate is not 100%, and appears to be lower in patients with a cardiac resynchronization therapy (CRT) indication rather than a bradycardia indication for pacing. The mechanisms for failure to advance the lead through the ventricular septum are not well understood. Purpose; We used pre-procedural CMR to determine whether there are features which can help identify patients where lead implantation may be challenging. We assessed whether the extent and location of septal late gadolinium enhancement identified patients in whom left bundle area pacing will be challenging. We hypothesized that the presence of extensive scar in the septum impedes advancing the lead to the left ventricular septum and prevents capture of the left bundle. Methods; Patients underwent cardiac MRI including motion corrected free-breathing late gadolinium enhancement imaging1 before implantation. Scar was quantified using the full height half maximum method and expressed as the overall proportion of myocardial mass in the basal anteroseptal and basal inferoseptal segments, as shown in Figure 1. Left bundle area pacing was then attempted in patients with a CRT indication for pacing. We compared the extent of septal scar between patients in whom left bundle area pacing was achieved and those where there was failure to advance the lead deep into the septum. Results; 12 patients (11 male, 1 female), with average age 72 (IQR 63 to 78) and LVEF 30% (IQR 26 to 33) were studied. There was failure to advance the lead deep into the septum in 4 patients. There was a significantly higher basal septal scar burden in those patients where there was failure to advance the left bundle lead compared to those in which left bundle capture was achieved as shown in Figure 2 (median 55% and 5% respectively, p-value 0.02 by Wilcoxon signed rank test). Conclusion; The presence and extent of late gadolinium enhancement in the basal septum appears to be an important determinant of successful implantation of left bundle pacing lead using current implant technology. This may be because extensive septal scar prevents advancement of the pacing lead through the septum. Cardiac MRI before left bundle area pacing is likely to be useful in procedural planning.