Extensive Late Gadolinium Enhancement Research Articles

Identification of high-risk imaging features in hypertrophic cardiomyopathy using electrocardiography: A deep-learning approach

BackgroundPatients with hypertrophic cardiomyopathy (HCM) are at risk of sudden death, and individuals with ≥1 major risk markers are considered for primary prevention implantable cardioverter-defibrillators. Guidelines recommend cardiac magnetic resonance (CMR) imaging to identify high-risk imaging features. However, CMR imaging is resource intensive and is not widely accessible worldwide. ObjectiveThe purpose of this study was to develop electrocardiogram (ECG) deep-learning (DL) models for the identification of patients with HCM and high-risk imaging features. MethodsPatients with HCM evaluated at Tufts Medical Center (N = 1930; Boston, MA) were used to develop ECG-DL models for the prediction of high-risk imaging features: systolic dysfunction, massive hypertrophy (≥30 mm), apical aneurysm, and extensive late gadolinium enhancement. ECG-DL models were externally validated in a cohort of patients with HCM from the Amrita Hospital HCM Center (N = 233; Kochi, India). ResultsECG-DL models reliably identified high-risk features (systolic dysfunction, massive hypertrophy, apical aneurysm, and extensive late gadolinium enhancement) during holdout testing (c-statistic 0.72, 0.83, 0.93, and 0.76) and external validation (c-statistic 0.71, 0.76, 0.91, and 0.68). A hypothetical screening strategy using echocardiography combined with ECG-DL–guided selective CMR use demonstrated a sensitivity of 97% for identifying patients with high-risk features while reducing the number of recommended CMRs by 61%. The negative predictive value with this screening strategy for the absence of high-risk features in patients without ECG-DL recommendation for CMR was 99.5%. ConclusionIn HCM, novel ECG-DL models reliably identified patients with high-risk imaging features while offering the potential to reduce CMR testing requirements in underresourced areas.

Optimal timing of follow-up cardiac magnetic resonance in patients with uncomplicated acute myocarditis

BackgroundCardiac magnetic resonance (CMR) is central in the diagnosis and prognostic stratification of acute myocarditis (AM) but the timing of repeated CMR scans to assess edema resolution and late gadolinium enhancement (LGE) stabilization remain unclear.We assessed edema and LGE evolution over 12 months to identify the optimal timing of repeat CMR evaluation in AM. Methods and resultsThirty-three consecutive patients with AM underwent CMR at clinical presentation (CMR-1), after 3 months (CMR-2) and after 12-months (CMR-3). CMR included assessment of edema and LGE, left ventricular ejection fraction (LVEF) and left ventricular mass index (LVMi). After CMR-3 patients were followed-up every three-months by clinical evaluation, Holter-monitoring, and echocardiography.All patients had edema and LGE at CMR-1. At CMR-2 edema-positive segments (0.42 ± 0.34 vs. 3.18 ± 2.33, p < 0.005), LGE (4.98 ± 4.56 vs. 9.60 ± 8.58 g, and 4.22 ± 3.97% vs 7.50 ± 5.61%) and LVMi (69.82 ± 11.83 vs 76.06 ± 13.13 g/m2) (all p < 0.0001) significantly reduced, while LVEF (63.12 ± 5.47% vs.61.15 ± 6.87% p < 0.05) significantly improved, compared to CMR-1. At CMR-2 edema persisted in 7 patients (21%) but resolved at CMR-3 with no further changes of LVMi, LVEF and LGE. During follow-up (85 ± 15 months), 5 (15%) patients showed persistent ventricular arrhythmias. Univariate predictors of arrhythmic persistence were LGE extension at CMR-2 and CMR-3 (both p < 0.05), but not at CMR-1 (p = 0.07). ConclusionsMost patients with uncomplicated AM show edema resolution with LGE stabilization after 3 months. Further CMR evaluations should be limited to patients with persisting edema at this time. LGE extent measured after edema resolution is associated with persistent ventricular arrhythmias.

Left atrial strain and long-term risk of atrial fibrillation in hypertrophic cardiomyopathy

Abstract Background The prevalence of atrial fibrillation (AF) in hypertrophic cardiomyopathy (HCM) patients is higher than in the general population, and it is associated with an increased risk of adverse outcomes, such as stroke, heart failure, and mortality. The left atrium (LA) plays an important role in maintaining normal cardiac function, and alterations in its structure and function can contribute to the development of AF. LA strain, a surrogate of LA remodeling, has been suggested a predictor of future AF. Purpose The aim of this study was to explore risk factors of new onset AF highlighting LA strain in patients with HCM. Methods Among a prospective cohort of 865 HCM patients collected at two large tertiary centers, 696 with adequate echocardiographic images to measure LA strain without a history of AF were included in the analysis. LA strain was measured on apical four-chamber view at initial evaluation using vendor-independent speckle-tracking software. The primary endpoint was new onset AF during 10 years after initial evaluation. Results The median age was 55.0 years and 74.3% were male. A median value of LA reservoir strain (LARS) was 26.2 % [interquartile range 20.4, 33.3]. Among the 696 patients, 66 had new onset AF 10 years, with a 10-year incidence of 15.8%. The unadjusted risk factors for new onset AF were previous stroke, non-apical HCM, family history of HCM, non-sustained ventricular tachycardia, obstructive HCM, extensive late gadolinium enhancement, larger LA diameter, larger LA volume, and lower LARS. LARS remained an independent predictor of new onset AF in multivariable analysis. The best cut-off value of LARS was 17.9% (hazard ratio 4.00, 95% confidence interval 2.44–6.55, p&amp;lt;0.001). Compared with LARS ≥17.9%, LARS &amp;lt;17.9% was significantly associated with a higher incidence of new onset AF, irrespective of presence of clinical risk factors (Figure 1) and LA enlargement (Figure 2). Conclusions In patients with HCM, low LA strain is an independent predictor of new onset AF.

Abstract 16793: The Impact of Late Gadolinium Enhancement on Sudden Death Risk Stratification in Older Patients With Hypertrophic Cardiomyopathy

Background: Extensive late gadolinium enhancement (LGE) is now recognized as a risk factor for sudden cardiac death (SCD) in patients with hypertrophic cardiomyopathy (HCM). However, risk for SCD is very low in older (≥60 years) HCM patients, and therefore utility of assessing LGE for risk stratification in this subgroup of patients is uncertain. Objectives: We assessed the relationship between LGE and SCD in older HCM patients and compared this risk to younger patients. Methods: A total of 1735 HCM patients undergoing cardiovascular magnetic resonance (CMR) for initial evaluation from 4 medical centers were followed up for a median of 3.7 years. LGE was semiautomatically quantified by manually adjusting a grayscale threshold. Results: We identified 638 HCM patients ≥60 years of age (up to 90 years), with LGE present in 337 patients (53%), including 28 patients (4%) with extensive LGE occupying ≥15% of left ventricular mass. Neither the presence nor extent of LGE was associated with increased risk for SCD events (HR ad , 1.13; 95%CI, 0.20-6.44, p=0.89 and HR ad per 10% increase, 1.49; 95%CI, 0.46-3.28, p=0.38, respectively), even after adjustment for other relevant disease variables. The risk for SCD at five years was 4% in older HCM patients with extensive LGE ≥15%, and not different compared to older patients with less LGE (1.0%, p=0.25). The performance of the AHA/ACC SCD risk model was not enhanced in older HCM patients by the addition of LGE (continuous net reclassification index, 0.25; 95%CI, -0.35-0.85, p=0.42). In contrast, the extent of LGE was associated with increased SCD risk in patients &lt;60 years, with extensive LGE associated with a 3-fold greater risk. Conclusions: The extent of LGE was not associated with increased SCD risk in HCM patients ≥60 years, even in the presence of other risk markers. These data suggest a limited role for CMR with LGE in older HCM patients to inform SCD risk stratification.

Assessment of late gadolinium enhancement in hypertrophic cardiomyopathy improves risk stratification based on current guidelines.

Identifying patients with hypertrophic cardiomyopathy (HCM) who are candidates for implantable cardioverter defibrillator (ICD) implantation in primary prevention for sudden cardiac death (SCD) is crucial. The aim of this study was to externally validate the 2022 European Society of Cardiology (ESC) model and other guideline-based ICD class of recommendation (ICD-COR) models and explore the utility of late gadolinium enhancement (LGE) in further risk stratification. Seven hundred and seventy-four consecutive patients who underwent cardiac magnetic resonance imaging were retrospectively enrolled. Forty-six (5.9%) patients reached the SCD-related endpoint during 7.4 ± 2.5 years of follow-up. Patients suffering from SCD had higher ESC Risk-SCD score (4.3 ± 2.4% vs. 2.8 ± 2.1%, P < .001) and LGE extent (13.7 ± 9.4% vs. 4.9 ± 6.6%, P < .001). Compared with the 2014 ESC model, the 2022 ESC model showed increased area under the curve (.76 vs. .63), sensitivity (76.1% vs. 43.5%), positive predictive value (16.8% vs. 13.6%), and negative predictive value (98.1% vs. 95.9%). The C-statistics for SCD prediction of 2011 American College of Cardiology (ACC)/American Heart Association (AHA), 2014 ESC, 2020 AHA/ACC, and 2022 ESC models were .68, .64, .76 and .78, respectively. Furthermore, in patients without extensive LGE, LGE ≥5% was responsible for seven-fold SCD risk after multivariable adjustment. Whether in ICD-COR II or ICD-COR III, patients with LGE ≥5% and <15% showed significantly worse prognosis than those with LGE <5% (all P < .001). The 2022 ESC model performed better than the 2014 ESC model with especially improved sensitivity. LGE enabled further risk stratification based on current guidelines.

Endocardial versus whole-myocardial tracking global longitudinal strain analysis in patients with hypertrophic cardiomyopathy: A preliminary comparative study.

We investigated whether the feasibility of left ventricular (LV) global longitudinal strain (GLS) in hypertrophic cardiomyopathy (HCM) varies according to the methodology (e.g. endocardial vs. whole myocardial tracking techniques). We retrospectively analyzed 111 consecutive patients with HCM (median age, 58 years; male, 68.5%) who underwent both transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (apical 29.7%, septal 33.3%, and diffuse or mixed 37.0%). TTE-whole myocardial and TTE-endocardial GLS were measured and compared in terms of association with late gadolinium enhancement (LGE) extent and discrimination performance for extensive LGE (>15% of the LV myocardium). Although TTE-whole myocardial and TTE-endocardial GLS were significantly correlated, absolute TTE-endocardial GLS values (19.3 [16.2-21.9] %) were higher than TTE-whole myocardial GLS values (13.3[10.9-15.6] %, p<0.001). Both TTE-derived GLS parameters were significantly correlated with the LGE extent and independently associated with extensive LGE (odds ratio [OR] 1.30, p = 0.022; and OR 1.24, p = 0.013, respectively). Discrimination performance for extensive LGE was comparable between TTE-whole myocardial and TTE-endocardial GLS (area under the curve [AUC], 0.747 and 0.754, respectively, pdifference = 0.610). However, among patients with higher LV mass index (>70 g/m2), only TTE-whole myocardial GLS correlated with LGE extent and was independently associated with extensive LGE (OR 1.35, p = 0.042), while TTE-endocardial GLS did not. Additionally, TTE-whole myocardial GLS had better discrimination performance for extensive LGE than TTE-endocardial GLS (AUC, 0.705 and 0.668, respectively, pdifference = 0.006). TTE-derived GLS using either the endocardial or whole myocardial tracking technique is feasible in patients with HCM. However, in those with severe hypertrophy, TTE-whole myocardial GLS is better than TTE-endocardial GLS.

Clinical and cardiac magnetic resonance profile in patients with partial late gadolinium resolution at 6 months after acute myocarditis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Cardiovascular magnetic resonance (CMR) is established as the gold standard non-invasive test for the diagnosis of acute myocarditis. However, current evidence on CMR after an acute myocarditis in the follow-up is contradictory. There are patients who can show an improvement on late gadolinium enhancement (LGE) extension but timing for CMR follow-up and the amount of this improvement is unclear. A better comprehension of patients’ profiles is therefore needed. Purpose To explore the clinical profile and index CMR findings in patients with acute myocarditis and persistent LGE in follow-up CMR focusing on the differences between those who present mild improvement (less than fifty percent of previously affected segments) versus patients who present a better improvement (more than fifty percent). Methods All patients with an acute myocarditis diagnosis from June 2021 to June 2022 and a follow-up CMR were retrospectively evaluated. Myocarditis was defined by modified Lake Louise criteria (mLLC). Electronic medical records were analyzed to collect data on baseline clinical variables, CMR features, treatment and follow-up events. A CMR was performed on follow-up based on clinician’s criteria. Results A total of 49 consecutive patients fulfilled updated LLC for myocarditis. 30 cases (61.2 %) had a follow-up CMR. The mean time to first CMR control was 186 +/- 95 days (6,2 months). After excluding patients with no LGE at index CMR, 22 patients were analysed. Of those, 13 had reduced LGE extent in less than fifty percent of previously affected segments, and 9 showed an improvement of more than fifty percent. There were no differences in cardiovascular risk factors or baseline comorbidities (Table 1). There were no differences between groups in terms of left and right ventricular ejection fraction. T1, T2 and ECV maps were similar en both groups. Patients with less LGE improvement tend to have more initial edema extension although this tendency was not statistically significant whilst there were no differences in LGE extension at index CMR. Both groups presented similar affected segments and in both cases inferolateral segments were the most affected (Table 2). There were no differences in clinical events after 13 months of mean follow-up time, there were no differences between groups regarding to corticoid, colchicine and NSAID prescription. Conclusions In our cohort, there were no differences in baseline characteristics, CMR findings, treatment and clinical events between patients with significant LGE improvement at 6 months after an acute myocarditis and those with only mild improvement.

Exploring the prognostic value of myocardial inflammation in Fabry cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Cardiac involvement in Fabry Disease (FD) manifests as left ventricular hypertrophy (LVH) often complicated by myocardial fibrosis and/or inflammation. Indeed, glycosphingolipid storage does not explain the whole spectrum of FD pathophysiology. Lysosomal deposits of unmetabolized glycolipid substrates stimulate the activation of immunological pathways, taking to a chronic inflammatory process.1 In a subgroup of FD patients with late gadolinium enhancement (LGE), signs of myocardial inflammation can be detected by cardiac magnetic resonance (CMR) using T2-weighted (T2w) sequences and T2 mapping. T2 value in inferolateral wall (IL) has been described as the strongest predictor of increase in troponin level. 2 Aim The aims of the study were: 1) to compare CMR parameters in LVH and LGE positive FD patients with and without myocardial inflammation; 2) to verify if myocardial inflammation plays an incremental prognostic role in FD compared to LVH and LGE. Methods Among 190 consecutive FD patients referred for CMR, 47 patients with LVH and LGE were selected for this study. All patients underwent an extensive CMR protocol to provide a detailed evaluation of cardiac morphology and function, with multiparametric tissue characterization. Myocardial inflammation was detected by T2w and T2 mapping sequences. A comparison of CMR parameters between patients with and without inflammation was performed. A composite endpoint of cardiovascular (CV) events was used for survival analysis. Results No differences in age and Mainz Severity Score Index were found between LVH+/LGE+ FD patients with and without myocardial inflammation. Patients with inflammation showed significantly greater left ventricular mass index (LVMI) compared to patients without inflammation. Regarding tissue characterization, patients with myocardial inflammation had more extensive LGE and significantly higher ECV in IL wall. Native myocardial T1 was reduced in both groups without statistically significant difference. (Table 1) Myocardial inflammation always involved IL wall. During a median follow-up of 30 months, Kaplan-Meier curves showed similar event-free survival probability in patients with and without myocardial inflammation (Log-Rank p = 0,215, Figure 1). Conclusion In a population of LVH+/LGE+ FD patients, the presence of CMR signs of myocardial inflammation was associated with more severe LVH and more extensive LGE. However, the presence of myocardial inflammation did not showed an incremental prognostic value on CV outcomes on top of LVH and LGE. Larger studies are needed to verify this findings.

Late gadolinium enhancement persistence in early cardiac magnetic resonance follow-up after acute myocarditis

Abstract Funding Acknowledgements Type of funding sources: None. Background Multiparametric cardiac magnetic resonance (CMR) evaluation with modified Lake Louise criteria (mLLC) is the gold standard non-invasive test for the diagnosis of acute myocarditis. Although CMR in the follow-up may inform of edema resolution and myocardial fibrosis there is a lack of consensus on the optimal time interval to perform it and the clinical and prognostic differences between patients with complete resolution and those who present late gadolinium enhancement (LGE) persistence. Purpose To describe the clinical profile, CMR findings, early CMR follow-up and clinical events in patients with acute myocarditis focusing on the differences between patients who present complete LGE resolution versus patients with LGE persistence. Methods All patients who underwent a CMR for a suspected myocarditis during a period of 1 year from June 2021 to June 2022 were retrospectively evaluated. Those with a confirmed myocarditis by mLLC and a follow-up CMR were included. Electronic medical records were analyzed to collect data on baseline clinical variables, CMR features and follow-up events. Follow-up CMR was performed on follow-up based on clinician’s criteria. Results A total of 27 patients fulfilled mLLC for myocarditis during the period of study and had a follow-up CMR. The mean time to first CMR control was 186 +/- 95 days (6,2 months). Of those 23 (85.2%) presented persistent LGE enhancement and 4 of them presented a complete resolution of LGE. There were no statistically significant differences between groups although patients with complete LGE resolution tend to be younger. There were no differences between groups in terms of LVEF and RVEF. Patients with persistent LGE in the follow-up tend to have higher edema and LGE extension during the acute myocarditis episode, being the LGE difference statistically significant. In the follow up CMR almost all patients presented edema resolution and although the majority of patients (85.2%) presented LGE persistence they presented a trend to a decrease of affected segments (4.4 to 3.1 after mean time of 6 months). There were no differences in clinical events between groups in terms of death, admissions, ventricular arrhythmias and new episodes of myocarditis, patients with persistent LGE tend to have more visits for unresolved chest pain. Conclusions The majority of patients with a confirmed acute myocarditis had edema resolution and LGE persistence after 6 months. There were no differences in clinical events during follow-up. Follow up CMR before 6 months can prove resolving edema but LGE persistance is common. Further studies are needed to define the optimal interval to perform CMR after the index event.

Determinants of cardiopulmonary exercise test responses in hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Exercise capacity and ventilatory efficiency are often altered in hypertrophic cardiomyopathy (HCM) and several factors have been advocated as possible causes. Aim This study investigates the determinants of cardiopulmonary exercise test (CPET) prognostic markers for HCM (VO2Peak, VE/VCO2 Slope and PETCO2 apex), by considering echocardiographic and cardiac magnetic resonance (CMR) parameters. Secondly, it scopes if myocardial fibrosis at CMR leads to clinical and functional differences. Methods 64 patients with HCM underwent a clinical assessment, including maximal CPET, echocardiography, and CMR. Exclusion criteria were the corrective surgery for cardiac hypertrophy and heart failure stage. Results The study included 66% males, age 40±17 years, NYHA class I or II 91%. Mean left ventricle (LV) ejection fraction was 63,8±7,7%, with a mean LV maximal wall thickness (MVT) of 20,2±5,6 mm; LVOT gradient was &amp;gt;30mmHg in 14% of patients. Late gadolinium enhancement (LGE) was described in 70,3% of cases with a mean LGE extension on bullseye plot of 11%. 39% of patients had a VO2 peak &amp;lt;80% of predicted, 35% a reduced PETCO2 apex and 26% an increased VE/VCO2 Slope. At the stepwise multivariate analysis, age (β=-0,33; p=0,00), BMI (β=-0,80; p=0,002), systolic blood pressure increase (β=0,22; p=0,02), left atrial volume (β=-0,15; p=0,02) and BB therapy (β=-0,45; p=0,00) were independently associated with VO2 peak (R2-adjusted index 0,95). Concerning ventilatory efficiency, sex (β=-0,41; p=0,03), left atrial volume (β=0,46; p=0,01) and LGE extension (β=0,33; p=0,01) were independently associated with VE/VCO2 Slope (R2-adjusted index 0,46). Similar data, with reversed correlations, emerged for PETCO2 apex. Patients with LGE had a LV mass index (mean 104,6 vs 82,7 g/m2, p=0,04), MWT (mean 21,8 vs 16,2 mm, p=0,00) and diastolic function (mean E/e’ 13,4 vs 10,0, p=0,01) worse that the counterpart. No differences were found in sex, age, therapy, CPET parameters and arrhythmic burden. BB+ patients were older, had more LV hypertrophy, worse diastolic parameters, and functional capacity while ventilatory efficiency was similar. Conclusions This study supports previous data about VO2 peak determinants. The correlation between the extension of the LGE and ventilatory efficiency in patients with HCM is an original finding. It confirms the pathophysiological explanation of a lung ventilation/perfusion mismatch due to the increased left atrium pressure that is secondary to a more severe LV diastolic disfunction in patients with LGE. The reduced VO2 in BB+ compared to BB- patients is not inferable given the different age and severity of disease. Moreover, the negative chronotropic effect of BB during exercise prolongs the diastolic filling time, thus, improving stroke volume and alleviating the LV filling pressures, thus normalising, in the less advanced stages of pathology, the ventilatory efficiency in HCM patients.

MP-453086-7 ATRIOVENTRICULAR JUNCTION ABLATION AND CARDIAC RESYNCHRONIZATION THERAPY IN PATIENTS WITH NONOBSTRUCTIVE HYPERTROPHIC CARDIOMYOPATHY AND PERMANENT ATRIAL FIBRILLATION

Atrial fibrillation (AF) is the most common arrhythmia encountered with hypertrophic cardiomyopathy (HCM) and is associated with adverse cardiovascular outcomes. The outcomes of ablate-and-pace strategy for the management of refractory AF in HCM patients are unclear. The objective of this retrospective study was to investigate the incremental benefit and safety of atrioventricular junction (AVJ) ablation and biventricular pacing (CRT) in patients with nonobstructive (NO) HCM and symptomatic permanent AF. Between January 2016 and December 2021, 20 patients with NO-HCM underwent AVJ ablation + CRT for uncontrolled permanent AF. The control group included 86 NO-HCM patients with permanent AF treated by the best medical rate-control therapy. A 1:1 propensity score (PS) matching analysis weighted on clinical (age, gender, hypertension, diabetes, recent hospitalization for heart failure [HF], cerebrovascular accident, chronic kidney disease, NYHA class) and imaging characteristics (left ventricle [LV] ejection fraction [EF], left atrial dimension, estimated pulmonary hypertension, maximal wall thickness, late gadolinium enhancement extension) was performed to compare outcomes between groups. The primary endpoint was a composite of all-cause mortality and hospitalization due to HF during follow-up. PS matching yielded 40 patients, 20 patients with AVN ablation + CRT (Group 1), and 20 patients in best medical rate-control therapy (Group 2). CRT was achieved in all patients (100% CRT-D). No acute procedure-related complications were noted. The mean paced QRS duration was 119±12 ms. Within the matched cohort, mean age was 64±7 years, the median time since AF diagnosis was 2 years (IQR 0.8-2.3 years), the mean LV EF was 53%±5%. During a median follow-up period of 23 months (IQR 19-27 months), patients in Group 1 had a lower risk of primary outcomes (HR 0.7; 95% CI 0.47-0.92; p=0.04), mainly driven by a significantly lower risk of HF hospitalization (HR 0.4; 95% CI 0.23–0.75; p=0.02). Compared to Group 2, Group 1 experienced a significant improvement in LV EF (55%±5% [Group 1] vs 48%±6% [Group 2], p=0.03) and improvement in NYHA class. No long-term device-related complications were noted. Ablation of AVJ + CRT was safe and superior to medical therapy in reducing HF hospitalization in patients with NO-HCM and permanent AF.

Mitochondrial Cardiomyopathy: Distinctive Cardiac Phenotype Detected with Cardiovascular MRI

Left ventricular hypertrophy (LVH) has a broad differential diagnosis. Pathogenic variants of mitochondrial DNA are a rare cause of LVH, and cardiac MRI is a powerful technique that may aid in differentiating such rare causes. This case report presents three siblings with a pathogenic variant of the mitochondrially encoded tRNA isoleucine (MT-TI) gene. A distinctive cardiac phenotype was detected with cardiac MRI. Extensive LVH and dilatation and decreased ejection fraction were observed with a pattern of increased T2 signal and extensive late gadolinium enhancement, which was remarkably consistent among all three siblings. Keywords: Cardiomyopathies, MR Imaging, Hypertrophic Cardiomyopathy, Mitochondrial, Inherited Cardiomyopathy, Left Ventricular Hypertrophy, Cardiovascular MRI, Late Gadolinium Enhancement Supplemental material is available for this article. © RSNA, 2023.

Diagnosis of cardiac sarcoidosis in patients presenting with cardiac arrest or life-threatening arrhythmias

ObjectiveCardiac sarcoidosis (CS) may present with cardiac arrest or life-threatening arrhythmias. There are limited data on this subgroup of patients with CS. Advanced imaging including cardiovascular magnetic resonance (CMR) and...

Use of Cardiac Magnetic Resonance Imaging to Distinguish Between Acute Myocarditis and Takotsubo Cardiomyopathy

Use of Cardiac Magnetic Resonance Imaging to Distinguish Between Acute Myocarditis and Takotsubo Cardiomyopathy

225 PROGNOSTIC ROLE OF EARLY CARDIAC MAGNETIC RESONANCE IN MYOCARDIAL INFARCTION WITH NON-OBSTRUCTIVE CORONARY ARTERIES (MINOCA)

Abstract Background Myocardial infarction with non-obstructive coronary arteries (MINOCA) represents a significant proportion of acute myocardial infarction (AMI) population. MINOCA is a working diagnosis and an accurate investigation of the underlying causes should always be performed. In this setting, cardiac magnetic resonance (CMR) imaging plays a pivotal diagnostic role. However, a prognostic stratification based on the CMR findings in ischemic MINOCA is still unavailable. Purpose To evaluate the potential prognostic impact of specific CMR findings - especially ischemic late gadolinium enhancement (LGE) patterns - in order to look for measurable parameters that may guide the management of this still troubled clinical entity. Methods We assessed 461 MINOCA from January 2016 to June 2021. We excluded acute myocarditis, Tako-tsubo syndromes, cardiomyopathies, or non-pathological CMR. According to CMR findings, MINOCA were classified in two phenotypes: LGE-positive (an ischemic subendocardial or transmural LGE pattern) or LGE-negative (cases without LGE but exhibiting regional myocardial injury defined by myocardial edema in a coronary territory with a typically ischemic "wave-front" and/or regional wall motion abnormality consistent with coronary distribution). All-cause mortality, re-infarction, stroke, heart failure (HF) and the composite endpoint (MACE) were evaluated. Extended LGE was considered as the presence of &amp;gt;2 segments with transmural LGE. The mean follow-up was 36.1 ± 15.2 months and CMR was performed at a mean of 6 ± 2.9 days from the acute presentation. Results The final cohort included 175 MINOCA with a likely-ischemic etiology: 121 (69.1%) constituted the LGE-positive group. The mean age of the study population was 62.3 ± 12.9 years and more than 61% were females. During follow-up, HF (15.7% vs 1.9%, p=0.008) and MACE (20.7% vs 7.4%, p=0.029) occurred more frequently in MINOCA "LGE-positive" compared to the "LGE-negative" ones. Extended LGE was significantly more prevalent in patients with versus without subsequent HF. On multivariable Cox regression, extended LGE was an independent predictor of HF occurrence (HR 18.49, 95%CI 4.65–73.61, p &amp;lt; 0.001) and MACE (HR 14.64, 95%CI 3.91–54.86, p &amp;lt; 0.001). Conclusions Our data suggest that in MINOCA patients the detection of LGE is correlated with the incidence of major cardiovascular events and heart failure during long-term follow-up. In fact, LGE extension was identified as the strongest predictor of cardiac adverse events. The early execution of CMR is useful in the prognostic stratification of MINOCA and this could guide the subsequent clinical and therapeutic management.

Desmoplakin cardiomyopathy-an inherited cardiomyopathy presenting with recurrent episodes of acute myocardial injury.

We present two female patients with recurrent episodes of myocardial injury, consisting of acute chest pain and elevated cardiac markers without coronary artery disease. Cardiovascular magnetic resonance imaging identified extensive late gadolinium enhancement suggestive of an inherited cardiomyopathy. Genetic testing showed heterozygous pathogenic variants in the desmoplakin (DSP) gene, the gene coding for the desmoplakin protein, astructural protein found in the cardiac desmosome. Pathogenic variants in the DSP gene are associated with dilated and arrhythmogenic cardiomyopathy. DSP cardiomyopathies may cause recurring myocardial injury mimicking an acute coronary syndrome or myocarditis. Cardiac magnetic resonance imaging is key in its diagnosis due to its specifying imaging features. Genetic testing is essential for the evaluation and confirmation of the diagnosis.

Updated risk assessments for sudden cardiac death in hypertrophic cardiomyopathy patients with implantable cardioverter-defibrillator.

Hypertrophic cardiomyopathy (HCM) is a genetic disease associated with a risk of malignant ventricular tachyarrhythmias and sudden cardiac death (SCD). Assessment of the SCD risk is crucial for its clinical management, and there has been considerable interest in developing risk stratification strategies. An implantable cardioverter-defibrillator (ICD) is a life-saving treatment for patients with HCM who are at a high-risk of ventricular tachyarrhythmias and SCD. However, a substantial number of ICD recipients experience adverse effects arising from inappropriate device therapy and implant-related complications. This has led to numerous investigations of the risk of SCD and the indications for ICD implantation. American guidelines were recently updated to include new risk markers, including left ventricular systolic dysfunction, apical aneurysm, and extensive late gadolinium enhancement, while European guidelines recommend individualized estimated 5-year SCD risk assessment models. Studies evaluating other risk factors for SCD in patients with HCM have also been published. Drawing on recent guidelines and publications on clinical risk factors, we focus this review on updated risk assessments for SCD with ICD therapy in patients with HCM.

Abstract 11885: Optimal Timing and Prognostic Value of Follow-Up Cardiac Magnetic Resonance in Patients With Acute Myocarditis

Background: cardiac magnetic resonance (CMR) is central for diagnosis, follow up and prognostic stratification of acute myocarditis. Late gadolinium enhancement (LGE) extent and persistence at follow-up represents a negative prognostic marker. However, time course of oedema resolution and LGE stabilization and optimal timing to repeat CMR are unclear. Hypothesis: we assessed time course of oedema and LGE evolution to identify optimal timing to repeat CMR in acute myocarditis. Methods: 36 acute myocarditis patients (35M, 28,8±10,3 years) underwent CMR at clinical presentation (CMR-1), after 3 months (CMR-2) and after 12-months (CMR-3). We assessed oedema and LGE and measured left ventricular ejection fraction (LVEF) and indexed mass (iLVM). After CMR-3 all patients were followed up yearly with clinical evaluation, Holter ECG and echocardiography. Results: all patients had oedema and LGE at CMR-1. At CMR-2 significant reduction of oedema (T2 positive segments 0,4±0,9 vs 4,1±3,2 p&lt;0.0001) and LGE (4,3±3,9 vs 7,5±5,6 p&lt;0.0001) was observed compared to CMR-1, with improvement of LVEF (62,7±5,6 vs 58,5±12,2% p&lt;0.05) and reduction of iLVM (71,2±13,7 vs 78,1±15,2 g/m2 p&lt;0.0001). At CMR-3 no further LGE reduction nor LVEF and iLVM improvement were observed. At 60±23-months follow-up, no major cardiovascular events nor myocarditis recurrences occurred. At Holter ECG 8/36 patients (28%) had non-sustained ventricular tachycardias. Ventricular arrhythmias were associated with lower LVEF at CMR-1 (46.25±19.55 vs 62.00±6.02 p=0.001) and higher LGE at CMR-2 (10.19±8.01 vs 3.60±3.14 p=0.007) but not with LGE at CMR-1 (10.05±7.14 vs 6.80±4.65 p=0.13). Conclusions: most patients with acute myocarditis present oedema resolution and LGE stabilization after 3 months. LVEF at baseline and LGE extension at second CMR correlates with ventricular arrhythmias persistence. Our findings redefine follow up and imaging-based prognostic stratification of acute myocarditis.

Microvascular Dysfunction Associates With Outcomes in Hypertrophic Cardiomyopathy: Insights From the Intravoxel Incoherent Motion MRI.

Although intravoxel incoherent motion (IVIM) MRI has emerged as an in vivo marker of tissue diffusion and perfusion, its prognostic value in patients with hypertrophic cardiomyopathy (HCM) remains unclear. To investigate whether IVIM-MRI derived parameters are associated with outcomes in patients with HCM. Prospective cohort. A total of 112 patients (51.72 ± 17.13 years) with suspected or known HCM. Single-shot echo planar IVIM imaging, balanced steady-state free precession, and phase-sensitive inversion-recovery late gadolinium enhancement (LGE) sequences at 3T. All patients were followed up of 29.3 ± 12.3 months for combined major adverse cardiac events (MACE) including cardiac death, aborted sudden death, heart transplantation, and rehospitalization for heart failure. The CVI42 imaging platform was used to assess morphological and functional MRI indices and to quantify LGE. The Body Diffusion Toolbox was used to derive pseudo diffusion (D*), water molecular diffusion (D) and perfusion fraction (f). Univariable and stepwise multivariable Cox model analyses were used to investigate the association between variables and composite endpoints. Kaplan-Meier curves were constructed to assess event-free survival, and the event rates were compared by the log-rank test. A total of 19 patients reached endpoints. Patients with MACE showed a significantly impaired D* value, lower f value, and more extensive LGE than those without MACE (all, P < 0.05), while there was no significant difference in D value (P=0.285). In the Cox regression models, D* value (hazard ratio [HR] 0.93; 95% CI: 0.88-0.98) and f value (HR 0.65; 95% CI: 0.45-0.92) were independent predictors for MACE. Moreover, in Kaplan-Meier survival analysis, the incidence of MACE was significantly higher in patients with decreased D* value and f value. Impaired D* and f values derived from IVIM-MRI are associated with adverse outcomes in patients with HCM. 2 TECHNICAL EFFICACY STAGE: 2.

Influence of novel risk markers on defibrillator implantation in hypertrophic cardiomyopathy

Abstract Background/Introduction To guide implantable defibrillator (ICD) use in hypertrophic cardiomyopathy (HCM), European Society of Cardiology (ESC) guidelines recommend using individualised sudden death (SCD) risk scores based on quantitative clinical data. Newly published American guidelines are based on the accumulation of binary risk markers, which include imaging-based novel risk markers (NRMs) that were absent from the development of the ESC's algorithm. These NRMs are ejection fraction &amp;lt;50%, apical aneurysm, and extensive late gadolinium enhancement on cardiac magnetic resonance (CMR) imaging. Purpose To assess how NRMs may have altered ICD prescription across ESC-based SCD risk status prior to publication of current American guidance. Methods We examined electronic records (2013–2020) of a subset of HCM patients with contemporaneous (within 12 months) CMR and echocardiography data for NRMs, ESC risk status, and ICD prescription. Differences in categorical data were assessed by Fisher's exact test. Results We studied 334 HCM patients (74% male; age: 58±14 years), of whom 83 (25%) were referred for ICD. ESC risk status was considered low, medium (4–6% 5-year SCD risk), or high in 264, 26, and 20 patients, for whom ICDs were recommended in 40 (15%), 20 (77%), and 18 (90%) patients, respectively. In patients with low SCD risk status, rate of ICD recommendation was significantly higher when ≥1 NRMs were present (34/126 – 27% vs. 0 NRMs: 6/138 – 4%; p&amp;lt;0.0001). NRMs did not appear to influence ICD recommendation in patients with medium (≥1 NRMs: 14/17 – 82% vs. 0 NRMs: 6/9 – 67%; p=0.6) or high (≥1 NRMs: 14/15 – 93% vs. 0 NRMs: 4/5 – 80%; p=0.4) SCD risk status (Figure 1). NRMs were less frequent in low risk patients than in high risk patients (126/264 – 48% vs. 15/20 – 75%; p&amp;lt;0.05), suggesting interaction between ESC status and NRMs (Figure 2). Conclusion NRMs have disproportionate influence on ICD prescription in low ESC risk HCM patients. However, NRMs are not independent of ESC risk status, suggesting iterative development of the ESC's algorithmic approach will be the most effective way of predicting SCD. Funding Acknowledgement Type of funding sources: None.