Distribution Of Late Gadolinium Enhancement Research Articles

Assessment of myocardial strain patterns in patients with left bundle branch block using cardiac magnetic resonance.

Recently, a classification with four types of septal longitudinal strain patterns was described using echocardiography, suggesting a pathophysiological continuum of left bundle branch block (LBBB)-induced left ventricle (LV) remodeling. The aim of this study was to assess the feasibility of classifying these strain patterns using cardiovascular magnetic resonance (CMR), and to evaluate their association with LV remodeling and myocardial scar. Single center registry included LBBB patients with septal flash (SF) referred to CMR to assess the cause of LV systolic dysfunction. Semi-automated feature-tracking cardiac resonance (FT-CMR) was used to quantify myocardial strain and detect the four strain patterns. A total of 115 patients were studied (age 66 ± 11years, 57% men, 28% with ischemic heart disease). In longitudinal strain analysis, 23 patients (20%) were classified in stage LBBB-1, 37 (32.1%) in LBBB-2, 25 (21.7%) in LBBB-3, and 30 (26%) in LBBB-4. Patients at higher stages had more prominent septal flash, higher LV volumes, lower LV ejection fraction, and lower absolute strain values (p < 0.05 for all). Late gadolinium enhancement (LGE) was found in 55% of the patients (n = 63). No differences were found between the strain patterns regarding the presence, distribution or location of LGE. Among patients with LBBB, there was a good association between strain patterns assessed by FT-CMR analysis and the degree of LV remodeling and LV dysfunction. This association seems to be independent from the presence and distribution of LGE.

Late gadolinium enhancement distribution patterns in non-ischaemic dilated cardiomyopathy: genotype-phenotype correlation.

Late gadolinium enhancement (LGE) is frequently found in patients with dilated cardiomyopathy (DCM); there is little information about its frequency and distribution pattern according to the underlying genetic substrate. We sought to describe LGE patterns according to genotypes and to analyse the risk of major ventricular arrhythmias (MVA) according to patterns. Cardiac magnetic resonance findings and LGE distribution according to genetics were performed in a cohort of 600 DCM patients followed at 20 Spanish centres. After exclusion of individuals with multiple causative gene variants or with variants in infrequent DCM-causing genes, 577 patients (34% females, mean age 53.5 years, left ventricular ejection fraction 36.9 ± 13.9%) conformed to the final cohort. A causative genetic variant was identified in 219 (38%) patients, and 147 (25.5%) had LGE. Significant differences were found comparing LGE patterns between genes (P < 0.001). LGE was absent or rare in patients with variants in TNNT2, RBM20, and MYH7 (0, 5, and 20%, respectively). Patients with variants in DMD, DSP, and FLNC showed a predominance of LGE subepicardial patterns (50, 41, and 18%, respectively), whereas patients with variants in TTN, BAG3, LMNA, and MYBPC3 showed unspecific LGE patterns. The genetic yield differed according to LGE patterns. Patients with subepicardial, lineal midwall, transmural, and right ventricular insertion points or with combinations of LGE patterns showed an increased risk of MVA compared with patients without LGE. LGE patterns in DCM have a specific distribution according to the affected gene. Certain LGE patterns are associated with an increased risk of MVA and with an increased yield of genetic testing.

PO-02-225 LATE GADOLINIUM ENHANCEMENT AT CARDIAC MAGNETIC RESONANCE YIELDS HIGH NUMBER OF FALSE POSITIVE DIAGNOSES IN ARRHYTHMOGENIC RIGHT VENTRICULAR CARDIOMYOPATHY

New diagnostic criteria have been proposed for arrhythmogenic right ventricular cardiomyopathy (ARVC). These proposed “Padua criteria” include late gadolinium enhancement (LGE) on cardiac magnetic resonance for the left ventricle (LV) and right ventricle (RV). Yet, the potential of LGE to distinguish ARVC from differential diagnoses remains unknown. Assess the diagnostic value of LGE to distinguish ARVC from its differentials. We included 130 subjects (57% male, 46±17 years) clinically diagnosed with ARVC as per 2010 Task Force Criteria (n=32, 84% PKP2 carriers), familial dilated cardiomyopathy as per World Health Organization criteria (n=25), myocarditis as per 2013 ESC position statement (n=13), sarcoidosis as per 2014 HRS expert consensus statement (n=20), biopsy-proven cardiac amyloidosis (n=19) and RV outflow tract-ventricular tachycardia (n=21). Presence and distribution of LGE was evaluated by an experienced radiologist using a 17-segment LV and 7-segment RV model. Presence of LGE was determined as per Padua criteria. Diagnostic value of RV-LGE and LV-LGE as per Padua criteria in ARVC vs. non-ARVC patients was evaluated with specificity, false positive rate (FPR) and accuracy. Distributions of LGE per subgroup are shown in the Figure. The RV-LGE criterion was equally often fulfilled in ARVC (n=16, 50%) vs. non-ARVC (n=43, 44%) patients, p=0.546. ARVC patients most often had RV-LGE in the RV inlet region (n=14/32, 44%). Consequently, the RV-LGE criterion yielded specificity 56%, FPR 44% and accuracy 55% for right-sided disease. In contrast, the LV-LGE criterion was significantly more often fulfilled in non-ARVC (n=71, 72%) vs. ARVC (n=11, 34%) patients, p<0.001. ARVC patients most often had LV-LGE in the inferolateral (n=10/11, 91%) wall, whereas it was more global in non-ARVC groups (median segments n=2 [IQR 2-6] ARVC vs. n=9 [IQR 4-15] non-ARVC, p<0.001). As such, the LV-LGE criterion yielded specificity 28%, FPR 72% and accuracy 29% for left-sided disease. LV-LGE is observed in one-third of ARVC patients, most often in the inferolateral region. RV-LGE is observed in half of ARVC patients, typically in the RV inlet region. Notably, LGE is often present in ARVC differentials. While LGE may be helpful to determine focal fibrosis, it may result in a large number of false positive diagnoses when included as a diagnostic criterion. Knowledge of LGE patterns can be useful for diagnostic classification.

Association between ECG parameters and late gadolinium enhancement along the course of myocarditis

Purpose: Numerous electrocardiogram (ECG) abnormalities and late gadolinium enhancement (LGE) in cardiac magnetic resonance imaging (CMR) have been related to poor prognosis in acute myocarditis. We evaluated whether ECG parameters are associated with the distribution and dynamic of LGE along the course of myocarditis. Methods: Fifty-one patients with CMR confirmed acute myocarditis were included who underwent CMR with LGE and 12-lead ECG at baseline and 3-month follow-up at our institution. The association between the presence, regional distribution and change of ECG parameters and LGE was investigated using linear regression analysis. LGE was quantified as visual presence score (VPS) and visual transmurality score (VTS). Results: Among many ECG parameters only > 1 mm ST-elevation (STE) was associated with VPS and VTS at baseline (β = 3.08 [95%CI: 1.75; 4.41], p = < 0.001 and β = 5.40 [95%CI: 1.92; 8.88], p = 0.004; respectively). STE was most frequent in lateral and inferior ECG-leads (48% and 31%) and it was associated with VPS and VTS in these localizations (p < 0.05 all), however no association between anterior-septal STE and LGE could be confirmed. At follow-up the regression of STE was associated with the regression of VPS and VTS in univariate analysis (β=-1.49 [95%CI: -2.41; -0.57], p = 0.003 and β=-4.87 [95%CI: -7.18; -2.56], p = 0.001, respectively), which remained significant for VTS using a multivariate model (β=-2.39 [95%CI: -3.32; -0.47], p = 0.019). Conclusion: Although we demonstrated some promising associations between STE and LGE, the usability of ECG to estimate the territorial involvement and dynamical changes of LGE along the course of myocarditis is generally limited and cardiac magnetic resonance should be considered for this purpose.

1043 INTEGRATED DIAGNOSIS AND TREATMENT IN EOSINOPHILIC MYOCARDITIS, THE IMPORTANCE OF TEAM AGAINST RARE CONDITIONS

Abstract Eosinophilic myocarditis is an inflammatory disease of the heart, even if rare, it could be a life-threatening condition, characterized by eosinophils infiltration of the myocardial tissue. First report of this type of endocarditis was reported by Löffler in 1935 and was described as an eosinophilic filling of endocardial cells with consequent myocardial fibrosis. Etiologically, viral infections are the prominent cause of myocarditis, especially the Coxsackie-B virus, drugs such as sumatriptan and canine Toxoplasma infections have been associated with eosinophilic myocarditis. Eosinophilia indeed (increase in eosinophils count in blood sample) has a similar etiology to eosinophilic myocarditis. However, as known from the literature, the relationship between myocardial damage and eosinophilia can have multiple etiologies, from hypersensitivity to autoimmune diseases but also malignancies. Clinically, its signs and symptoms present a wide spectrum of manifestations such as chest pain, dyspnea, rhythm disturbances, until sudden cardiac death. Diagnostic gold standard is endomyocardial biopsy, but cardiac magnetic resonance is a valid option in such scenarios following Lewis Lake criteria and suggestive laboratory results. We present the case of a 78-year-old lady, affected by arterial hypertension and dyslipidemia. Among her main comorbidities she complained late-onset asthma and hypothyroidism. The patient went to the emergency department of our hospital for onset of dyspnea associated with chest pain. An echocardiogram showed a dilated and diffusely hypokinetic left ventricle, severely reduced systolic function (EF 30%) and atrial fibrillation with high ventricular response. The patient presented with acute pulmonary edema and oliguria, for which non-invasive ventilation, diuretics therapy and inotropic therapy were needed. Invasive coronary angiography was negative, excluding any kind of coronary syndrome. HS-troponin peak detected was very high (73.170 ng/L). CMR was performed that showed images indicative of myocarditis (as shown in the picture A and B) with typical distribution of late gadolinium enhancement and reduced left ventricular function: The finding of hypereosinophilia was highly suspicious, so the endomyocardial biopsy performed confirmed the histotype of eosinophilic myocarditis. Hypereosinophilic myeloproliferative syndrome was ruled out after genetic testing. Therefore, a final diagnosis of eosinophilic granulomatosis with ANCA-negative polyangiotis with predominantly hematologic (peripheral hypereosinophilia), cardiac (multifocal myocarditis with inflammatory infiltrate with predominantly eosinophilic component), pulmonary (late-onset asthma) and peripheral neurologic (sciatic mononeuropathy) involvement was made. The patient underwent corticosteroid therapy, to which mepolizumab and cyclophosphamide were added. This case enlightens the rarity of this pathology, enhancing the appropriate indication of CMR in complex settings. We also remark the importance of close team collaboration with rheumatologists and CMR-expert radiologists for the resolution of the case and its proper therapeutic management.

Abstract 13193: Prevalence of Late Gadolinium Enhancement Following Pediatric Heart Transplantation Increases With Time Since Transplantation

Introduction: Chronic graft failure in pediatric heart transplant recipients (PHT) is associated with myocardial fibrosis on explanted specimens. Cardiac magnetic resonance imaging (CMR) is a validated, non-invasive method to detect myocardial fibrosis via the presence of late-gadolinium enhancement (LGE). In adult heart transplant recipients, LGE is associated with increased risk of hospitalization and death. We describe LGE on CMR among PHT and its associations with clinical and graft characteristics. Methods: We performed a retrospective chart review of all PHT who underwent CMR over a 6-year period at a single center (81 CMR studies, 59 unique patients). Two independent reviewers assessed the presence and distribution of LGE using the AHA 17-segment model. Clinical history and CMR-derived volumetry/ejection fraction were obtained; differences between LGE+ and LGE- PHT were evaluated. Results: Mean age at CMR was 14.8±4.6y; mean time since transplant was 7.3±5.0y. CMR indication was routine surveillance (without active rejection or history of cardiac allograft vasculopathy) in 63% (51/81) of studies. LGE was present in 36% (29/81). LGE patterns included: posterior hinge-point 27% (22/81), lateral wall 15% (12/81), and extensive, involving &gt;4 AHA segments, 7% (6/81) (Figure). Reviewing initial CMR per PHT (n=59), LGE+ patients were older (17 vs. 13y; p=0.001), with greater time since transplant (8.3 vs. 5.7y; p= 0.041). They demonstrated increased indexed LV end-systolic volume (35 vs. 29 ml/m2; p=0.011) and decreased LV ejection fraction (56.2 vs 60.6%; p=0.015). There were no significant differences in history of moderate/severe rejection or cardiac allograft vasculopathy. Conclusions: LV LGE was seen in about a third of PHT patients, more commonly in older patients with longer time since transplantation. Grafts with LGE show remodeling with lower LV ejection fraction. CMR-derived LGE may improve surveillance of chronic graft failure in PHT.

Effect of the cold pressor test on coronary flow reserve by cardiac magnetic resonance in patients with hereditary TTR+ amyloidosis

Abstract Background Cold pressor test (CPT) is a potent alpha-adrenergic vasoconstrictor stimulus and evaluates the sympathetic reactivity of the cardiovascular system during the immersion of a hand in cold water, its effect on coronary flow reserve (CFR) in patients with hereditary TTR+ amyloidosis is unknown. Purpose To evaluate CFR by CPT in hereditary TTR+ amyloidosis patients with different cardiac involvement regarding the distribution of late gadolinium enhancement (LGE) by cardiac magnetic resonance imaging (CMRI) and compare with healthy volunteers Methods It was a cross-sectional study of 22 hereditary TTR+ amyloidosis patients with different patterns of LGE (absence/minimum or extensive involvement), and 4 healthy controls without LGE. CPT was performed with immersion of one hand in four Celsius degrees temperated water. Phase-contrast images were acquired on rest and during stress (after four minutes of a hand immersion). Volume quantification was made in posterior analysis to determine flow differences. Results No statistically significant differences were found regarding left ventricular (LV) volumes, LV mass, LV ejection fraction, and atrial volumes comparing the three groups of patients. CFR was abnormal in both groups of TTR+ amyloidosis patients compared with higher values in healthy subjects. Nevertheless, no statistically significant differences were determined. Conclusions Hereditary TTR+ amyloidosis subjects presented with abnormal values of CFR even with minimal or non-LGE by CMRI in the setting of infiltration. This response hypothesized small vessel involvement due to early infiltration by amyloid deposits before LGE development. Funding Acknowledgement Type of funding sources: None.

Late gadolinium enhancement patterns in severe symptomatic high-gradient aortic stenosis

Abstract Background Left ventricular (LV) remodeling in patients with severe aortic valve stenosis (AS) is a complex process that goes beyond hypertrophic response and may involve reparative/replacement fibrosis. Currently, cardiac magnetic resonance (CMR) is the gold-standard imaging technique for detecting focal myocardial fibrosis through late gadolinium enhancement (LGE). However, myocardial fibrosis prevalence and distribution is quite variable among series. Our goal was to assess LGE prevalence and distribution pattern in severe symptomatic high-gradient AS. Methodology Single-center prospective cohort of 132 patients with severe symptomatic high-gradient AS (mean age 73±11 years; 48% male, mean valvular transaortic gradient 60±20 mmHg; mean aortic valve area 0.7±0.2 cm2/m2; mean LV ejection fraction by 2D echocardiogram 58±9%), all with normal flow (except one) undergoing surgical aortic valve replacement. Those with previous history of acute myocardial infarction, ischemic cardiomyopathy or other cardiomyopathy were excluded. All patients performed 1.5T CMR assessment with LV myocardium tissue characterization prior to surgery. Segmental LGE presence was assessed by two independent operators and classified according to the AHA 16 segment model, using 5-standard deviations from remote myocardium as the signal intensity cut-off for LGE identification and quantification. Results Overall, 96 patients (74%) had non-ischemic LGE (median LGE mass 3.2 g [IQR 0.2–8.3] g; median percentage of LGE myocardial mass 2.5% [IQR 0.1–6.1]%); 22 patients [17%] with exclusively junctional LGE); in one patient an incidental ischemic scar (subendocardial distribution) was identified. No cases of subepicardial distribution were found. Intramyocardial LGE was most frequently observed in basal and mid-anterior and inferior interventricular septum – see Figure 1. In these segments, LGE was most often junctional at right-ventricular insertion points (54%), followed by mid-wall LGE (32%) or both sites involvement (14%). Conclusion LGE is frequent in symptomatic high-gradient AS patients with preserved left ventricular ejection fraction, most often presenting as junctional enhancement in basal/mid-anterior and inferior interventricular septum. Future studies may address whether distinct LGE patterns may impact patient prognosis. Funding Acknowledgement Type of funding sources: None.

Adverse events prediction in nonischemic dilated cardiomyopathy by two machine learning models integrating clinical and cardiovascular magnetic resonance data

Abstract Funding Acknowledgements Type of funding sources: None. Background Risk stratification of patients with nonischemic dilated cardiomyopathy (NIDCM) is challenging. Machine learning (ML) models represent novel technologic tools that promise to improve predictive ability of cardiovascular adverse outcomes. Purpose To implement two ML models to predict the risk of adverse outcome (composite endpoint of all-cause death, heart transplantation, implantation of ventricular assistant device), in patients with NIDCM using clinical and radiological data. Methods We retrospective collected data from patients affected by NIDCM referred to our cardiologic unit between 2002 and 2018. Two ML models, an extreme gradient boosting machine (XGBoost) and an artificial neural network (ANN), were developed using cardiovascular magnetic resonance (CMR) and clinical parameters. Both models were trained on 67% of patients and evaluated based on the other 33% as internal validation. To investigate the contribution of different features in our models, we used Shapley additive explanations (SHAP) analysis. Results The final cohort resulted of 161 patients (mean age 48.9±13.6 years, 71% males), with a mean follow up duration of 79.1 months. During the follow-up 29 adverse event were observed (16 deaths, 12 heart transplantation, 1 implantation of ventricular assistant device). ANN model resulted in an accuracy of 76% with an area under the receiver operating characteristic (ROC) curve of 0.66; SHAP analysis identified male sex, percentage of late gadolinium enhancement (LGE) and LGE distribution in the lateral wall of myocardium as the main markers of adverse outcomes. XGBoost model resulted in an accuracy of 78% with a ROC curve of 0.76; SHAP analysis identified NT-proBNP level, age and serum creatinine mainly related with adverse outcomes. About CMR parameters, left ventricular diameter and ejection fraction better related with adverse outcomes. Conclusions Our models achieved a good performance in prediction of adverse events, suggesting that ML could improve our ability of risk stratification of NIDCM. XGBoost better performed than ANN, and SHAP analysis suggested that both CMR parameters and clinical parameters contribute to the definition of risk. ANN performance and SHAP analysisXGBoost performance and SHAP analysis

Viral Myocarditis: Classification, Diagnosis, and Clinical Implications.

Myocarditis is an inflammatory disease of the myocardium with focal or diffuse involvement. Viral infections are the most common cause of myocarditis, especially in Western countries. A recent viral illness with gastroenteric or upper respiratory symptoms often precedes myocarditis. The absence of specific pathognomonic features in conjunction with the wide spectrum of clinical manifestations that range from subclinical cases to sudden cardiac death (SCD) makes myocarditis diagnosis particularly challenging. Moreover, myocarditis might represent a cause of initially unexplained dilated cardiomyopathy (DCM) and heart failure (HF), especially among children and young adults. Cardiac magnetic resonance imaging (CMR) is crucial for myocarditis diagnosis, because of its ability to detect interstitial edema during acute inflammation. Assessment of subepicardial or mid-myocardial fibrosis by late gadolinium enhancement (LGE) is typical for myocarditis. Cardiac arrhythmias are frequent events that may arise especially in more severe myocarditis cases. The most common form of arrhythmia is atrial fibrillation, followed by ventricular tachycardia. Documented arrhythmias have been reported more commonly with HIV myocarditis than other more common infections such as Adenovirus, Parvovirus B19, human Herpes virus 6, and Enterovirus. The mechanisms of arrhythmogenesis in myocardial inflammation are not fully understood; in the acute phase, the spectrum of arrhythmogenesis ranges from a direct effect on cardiomyocytes that leads to electrical instability and ion channel impairment to ischemia from coronary macro- or microvascular disease. In chronic myocarditis, instead, myocardial replacement with fibrosis promotes scar-mediated re-entrant ventricular arrhythmias. Observational data suggested the important role of CMR, with LGE being the strongest independent predictor of SCD, cardiac, and all-cause mortality. In acute myocarditis, the most common localization of subepicardial LGE dwells in the lateral wall. Patients with myocarditis that develop HF and arrhythmias usually show a larger LGE distribution involving several myocardial segments. Moreover, a mid-layer LGE in the interventricular septum is more frequent in acute myocarditis than in acute coronary syndromes cases. The risk of SCD in patients with wide areas of LGE is significant, and a shared decision-making approach is warranted. Nevertheless, there is no formal consensus about the extension of LGE to justify implantable cardioverter defibrillator (ICD) implantation in primary prevention.

A cardiac magnetic resonance myocardial strain patterns analysis in left bundle branch block

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Recently, a classification with four types of septal longitudinal strain patterns was described using a speckle tracking based strain analysis in echocardiography suggesting pathophysiological continuum of LBBB-induced LV remodeling. Little data exist on feature tracking cardiac magnetic resonance (FT-CMR) in LBBB patients, and whether such patterns could be reproduced in CMR is not established yet. Purpose In this study, we aimed to: 1) Assess and reproduce the new strain patterns classification by CMR and 2) Evaluate its association with LV remodeling and myocardial scar in a LBBB cohort. Methods Single center registry which included LBBB patients with septal flash (SF) referred to CMR to assess the structural cause of LV dysfunction. LBBB was defined according to Strauss criteria as strict LBBB, non-strict LBBB or nonspecific LV conduction delay. A semi-automated FT-CMR was used to quantify myocardial strain and detect the four septal longitudinal and radial strain patterns, according to the recent classification (LBBB-1 through LBBB-4) – Figure. Extent of SF was visually scored as mild, moderate, or prominent. Results A total of 115 patients were included (mean age 66±11 years; 57% men; 38% with ischemic heart disease). Median duration of QRS was 150± 26ms and majority of the patients (n=90, 78%) were classified as strict LBBB. In longitudinal strain analyses LBBB-1 was observed in 23 (20%), LBBB-2 in 37 (32.1%), LBBB-3 in 25 (21.7%), and LBBB-4 in 30 (26%) patients. Patients at higher LBBB stages (longitudinal or radial pattern) had more prominent septal flash, greater LV volumes, lower LV ejection fraction and lower absolute global longitudinal, circumferential and radial strain values compared with patients in less advanced stages (p &amp;lt; 0.05 for all) - table. There was no difference between patterns in clinical characteristics, ischemic etiology, QRS duration and time delay between septal and lateral LV wall. Late gadolinium enhancement (LGE) was found in 63 patients (54.8%), with a septal location in 34 (29.6%) patients, lateral in 4 (3.5%) patients, septal and lateral in 11 (9.6%) patients. Furthermore, no difference was found for LGE presence, distribution or location between the four strain patterns. Conclusions Among patients with LBBB, our study found a good association between longitudinal and radial strain patterns with the degree of LV remodeling and LV dysfunction by FT-CMR analysis. Additionally, myocardial fibrosis didn’t seem to interfere with the staged LBBB classification.

Relationship Between Fragmented QRS Complex and Left Ventricular Fibrosis and Function in Patients With Danon Disease.

BackgroundFragmented QRS (f-QRS) complex on the surface ECG is a cardiac conduction abnormality that indicates myocardial scarring. The relationship between the f-QRS complex and cardiac status in patients with Danon disease (DD) remains unclear and will be explored in this study.MethodsPatients with genetically confirmed DD and cardiac magnetic resonance imaging (CMR) examinations were recruited from multiple centers. The number of leads, pattern, score, and segmental distribution of the f-QRS complex were assessed by surface 12-lead ECG. Cardiac status, such as left ventricular (LV) volume, function, and extent of late gadolinium enhancement (LGE), was demonstrated by CMR. The segmental distribution of LGE was also assessed. Correlations between the f-QRS and cardiac status were assessed.ResultsFifteen patients (14 men) with DD who underwent 12-lead ECG and CMR imaging were included. The f-QRS complex was documented in all patients (n = 15, 100%). Three patterns of f-QRS were found, with the notched R/S pattern (74%) being the most common, followed by fragmented QRS (16%) and various RSR' (11%). The fragmented QRS pattern showed an association with a higher level of myocardial fibrosis (LGE > 35%). The burden of f-QRS in each patient was assessed by the number of leads with f-QRS (median 7, range 2–12) and the f-QRS score (median 9, range 2–33). In the correlation analysis, the f-QRS score was positively correlated with LGE% (r = 0.726, p = 0.002), negatively correlated with LV ejection function (LVEF; r = −0.617, p = 0.014) as evaluated by CMR. In the local distribution, f-QRS score and LGE% were both predominant in the LV free wall but did not correlate well among the anterior, lateral, and inferior segments.ConclusionIn this DD cohort, the quantitative f-QRS was correlated well with myocardial fibrosis burden and LV dysfunction in general. This finding suggests that f-QRS can be used as a simple screening tool to assess cardiac status in patients with DD.

Early Diagnosis of Acute Myocarditis in the ED: Proposal of a New ECG-Based Protocol.

The diagnosis of acute myocarditis (AM) is based on a multi-parametric assessment including clinical presentation, ECG, imaging and biomarkers. Fragmented QRS (fQRS) might be an additional diagnostic sign in patients with proven AM. The main objective of this study was to assess the diagnostic yield of fQRS in patients with suspected AM presenting to the emergency department (ED). Patients admitted between January 2016 and March 2021 with a proven diagnosis of AM, according to clinical, cardiac magnetic resonance (CMR) and/or histologic criteria, were included in the analysis. In total, 51 patients were analyzed (41 men, 78%), with a median age of 36 (29–45) years. Thirty-three (65%) patients had prodromal flu-like symptoms. Patients presented to the ED mostly complaining of chest pain (68%) and palpitations (21%). Seven (14%) patients experienced cardiac arrest, one of whom died. At presentation, 40 patients (78%) displayed fQRS, and 10 (20%) presented ventricular arrhythmias. All the surviving patients underwent CMR and displayed late gadolinium enhancement (LGE). ECG leads showed that fQRS matched the LGE distribution in 38 patients (95%). The presence of fQRS is a simple clinical bedside tool to support the initial suspect of AM in the emergency department and to guide the most appropriate clinical workup.

Desynchronization Strain Patterns and Contractility in Left Bundle Branch Block through Computer Model Simulation.

Left bundle branch block (LBBB) is associated with specific septal-to-lateral wall activation patterns which are strongly influenced by the intrinsic left ventricular (LV) contractility and myocardial scar localization. The objective of this study was to propose a computational-model-based interpretation of the different patterns of LV contraction observed in the case of LBBB and preserved contractility or myocardial scarring. Two-dimensional transthoracic echocardiography was used to obtain LV volumes and deformation patterns in three patients with LBBB: (1) a patient with non-ischemic dilated cardiomyopathy, (2) a patient with antero-septal myocardial scar, and (3) a patient with lateral myocardial scar. Scar was confirmed by the distribution of late gadolinium enhancement with cardiac magnetic resonance imaging (cMRI). Model parameters were evaluated manually to reproduce patient-derived data such as strain curves obtained from echocardiographic apical views. The model was able to reproduce the specific strain patterns observed in patients. A typical septal flash with pre-ejection shortening, rebound stretch, and delayed lateral wall activation was observed in the case of non-ischemic cardiomyopathy. In the case of lateral scar, the contractility of the lateral wall was significantly impaired and septal flash was absent. In the case of septal scar, septal flash and rebound stretch were also present as previously described in the literature. Interestingly, the model was also able to simulate the specific contractile properties of the myocardium, providing an excellent localization of LV scar in ischemic patients. The model was able to simulate the electromechanical delay and specific contractility patterns observed in patients with LBBB of ischemic and non-ischemic etiology. With further improvement and validation, this technique might be a useful tool for the diagnosis and treatment planning of heart failure patients needing CRT.

Extracellular volume is an independent predictor of arrhythmic burden in dilated cardiomyopathy

The current stratification of arrhythmic risk in dilated cardiomyopathy (DCM) is sub-optimal. Cardiac fibrosis is involved in the pathology of arrhythmias; however, the relationship between cardiovascular magnetic resonance (CMR) derived extracellular volume (ECV) and arrhythmic burden (AB) in DCM is unknown. This study sought to evaluate the presence and extent of replacement and interstitial fibrosis in DCM and to compare the degree of fibrosis between DCM patients with and without AB. This is a prospective, single-center, observational study. Between May 2019 and September 2020, 102 DCM patients underwent CMR T1 mapping. 99 DCM patients (88 male, mean age 45.2 ± 11.8 years, mean EF 29.7 ± 10%) composed study population. AB was defined as the presence of VT or a high burden of PVCs. There were 41 (41.4%) patients with AB and 58 (58.6%) without AB. Replacement fibrosis was assessed with late gadolinium enhancement (LGE), whereas interstitial fibrosis with ECV. Overall, LGE was identified in 41% of patients. There was a similar distribution of LGE (without AB 50% vs. with AB 53.7%; p = 0.8) and LGE extent (without AB 4.36 ± 5.77% vs. with AB 4.68 ± 3.98%; p = 0.27) in both groups. ECV at nearly all myocardial segments and a global ECV were higher in patients with AB (global ECV: 27.9 ± 4.9 vs. 30.3 ± 4.2; p < 0.02). Only indexed left ventricular end-diastolic diameter (HR 1.1, 95%CI 1.0–1.2; p < 0.02) and global ECV (HR 1.12, 95%CI 1.0–1.25; p < 0.02) were independently associated with AB. The global ECV cut-off value of 31.05% differentiated both groups (AUC 0.713; 95%CI 0.598–0.827; p < 0.001). Neither qualitative nor quantitative LGE-based assessment of replacement fibrosis allowed for the stratification of DCM patients into low or high AB. Interstitial fibrosis, expressed as ECV, was an independent predictor of AB in DCM. Incorporation of CMR parametric indices into decision-making processes may improve arrhythmic risk stratification in DCM.

Patterns of Replacement Fibrosis in Hypertrophic Cardiomyopathy.

Background Myocardial replacement fibrosis is one of the major histologic features of hypertrophic cardiomyopathy (HCM), but its characteristics have not been well delineated. Purpose To clarify the characteristics of replacement fibrosis in HCM and to evaluate the prognostic value of the regional extent of fibrosis. Materials and Methods This prospective study evaluated participants with HCM who underwent contrast-enhanced cardiac MRI from March 2011 to April 2019. For each participant, global and 16-segment extent of late gadolinium enhancement (LGE) in the left ventricle (LV) at cardiac MRI was analyzed. The primary end point was all-cause death. Results Among the 798 study participants enrolled (median age, 49 years [interquartile range {IQR}: 38-59 years]; 508 men), 588 (74%) underwent whole-exome sequencing. Thirty-five participants (4%) experienced death from any cause during a median follow-up of 2.9 years (IQR: 1.5-4.7 years). Spearman analysis showed weak correlations between the extent of LGE and wall thickness (LGE of global LV and maximal LV wall thickness, r = 0.35 [P < .001]; LGE and thickness of septum, r = 0.30 [P < .001]). In the 16-segment model, the distribution of LGE was visually inhomogeneous and higher in the basal anterior, basal septal, midanterior, and midseptal regions (P < .001). This similar distribution of LGE was observed in participants with asymmetric septal hypertrophy, those with apical HCM, participants positive for mutation and those negative for mutation, and participants with MYH7 and MYBPC3 mutations. Cox analysis indicated that both the global extent of LGE (adjusted hazard ratio = 1.68 per 10% increase in LGE; P < .001) and the regional extent of LGE (ie, basal, midventricular, and apical regions of LV when on the short-axis view; septum, anterior free wall, inferior free wall, and lateral free wall when on the long-axis view) were associated with adverse outcomes. Conclusion In hypertrophic cardiomyopathy, myocardial replacement fibrosis weakly correlated with hypertrophy, was inhomogeneous and asymmetric, and was predominantly distributed in the interventricular septal wall and anterior free wall at the basal and mid levels. Greater extent of fibrosis was associated with poor prognosis, regardless of its location in the left ventricle. © RSNA, 2021 See also the editorial by Hanneman in this issue.

Magnetic resonance imaging of dilated cardiomyopathy: prognostic benefit of identifying late gadolinium enhancement in Asian patients.

Risk stratification in dilated cardiomyopathy (DCM) is imprecise, relying largely on echocardiographic left ventricular ejection fraction (LVEF) and severity of heart failure symptoms. Adverse cardiovascular events are increased by the presence of myocardial scarring. Late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) imaging is the gold standard for identifying myocardial scars. We examined the association between LGE on CMR imaging and adverse clinical outcomes during long-term follow-up of Asian patients with DCM. Consecutive patients with DCM undergoing CMR imaging at a single Asian academic medical centre between 2005 and 2015 were recruited. Clinical outcomes were tracked using comprehensive electronic medical records and mortality was determined by cross-linkages with national registries. Presence and distribution of LGE on CMR imaging were determined by investigators blinded to patient outcomes. Primary endpoint was a composite of heart failure hospitalisations, appropriate implantable cardioverter-defibrillator shocks and cardiovascular mortality. Of 86 patients, 64.0% had LGE (80.2% male; mean LVEF 30.1% ± 12.7%). Mid-wall fibrosis (71.7%) was the most common pattern of LGE distribution. Over a mean follow-up period of 4.9 ± 3.2 years, 19 (34.5%) patients with LGE reached the composite endpoint compared to 4 (12.9%) patients without LGE (p = 0.01). Presence of LGE, but not echocardiographic LVEF, independently predicted the primary endpoint (hazard ratio 4.15 [95% confidence interval 1.28-13.50]; p = 0.02). LGE presence independently predicted adverse clinical events in Asian patients with DCM. Routine use of CMR imaging to characterise the myocardial substrate is recommended for enhanced risk stratification and should strongly influence clinical management.

Aetiology-discriminative multimodality imaging of hypertrophic cardiomyopathy: deformation patterns relate to synchrotron-based assessment of microstructural tissue remodelling

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): Horizon 2020 European Commission Project H2020-MSCA-ITN-2016 (764738) and the Clinical Research in Cardiology grant from the Spanish Cardiac Society. Background The aetiology of left ventricular hypertrophy (LVH) is a relevant clinical challenge with consequences for patient management. Phenotypes resulting from hypertensive remodelling and sarcomere mutation often overlap. Synchrotron X-ray phase-contrast imaging (X-PCI) is a technique that can provide 3-dimensional detailed information on myocardial micro-structure non-destructively. The aim is to relate macrostructural/functional, non-invasive, imaging phenotypes of hypertrophic cardiomyopathy (HCM) to the underlying myocardial microstructure assessed with X-PCI. Methods Myocardial tissue samples were obtained from three patients (P1-3) with obstructive myocardial hypertrophy undergoing septal myectomy. Medical history and the 5-year HCM risk scores were evaluated. The patients were imaged with magnetic resonance imaging and echocardiography prior to procedure. Myocardial structure was assessed with wall thickness, late gadolinium enhancement (LGE), whereas function with speckle-tracking deformation (STE) and tissue Doppler imaging (TDI). Myectomy tissue was imaged with X-PCI in the TOMCAT beamline, using a multiscale propagation-based protocol combining a low-resolution (LR) and a high-resolution (HR) setup (5.8 and 0.7 um pixel size, respectively). Results The clinical and imaging data are shown in Fig 1. On initial assessment, wall thickness, LGE distribution, global longitudinal strain and septal TDI demonstrated a similar macrostructural and functional phenotype of P1 and P2, whereas P3 stood out with more severe hypertrophy, scarring and dysfunction. Additional regional deformation analysis with STE revealed reduced deformation in the basal and mid septum in P1, paired with a hypertensive pattern of post-systolic shortening (PSS) (yellow arrows). In comparison, in P2 and P3, deformation was more heterogeneous regionally, with regions of almost complete absence of deformation (orange arrows). Upon further exploration with TDI, areas with abnormal deformation were identified on the transition from basal to mid septum in both P2 and P3, whereas deformation was normal, but reduced in P1, and paired with PSS. LR X-PCI defined regions of interest to scan with HR (yellow frame), where HR revealed extensive interstitial fibrosis (orange arrow) with normal myocyte size and organisation in P1, compatible with severe hypertensive remodelling. However, in P2 and P3, patches of fibrosis (yellow arrow) paired with enlarged myocytes organized in visible disarray, considerably more prominent in P3, were both compatible with sarcomere-mutation HCM. Conclusion The results demonstrate multiscale phenotyping of HCM - relating micro- and macrostructural findings to function, and integrating multimodality data. In-depth regional deformation analysis, validated by synchrotron-based microstructural analysis, showed potential to identify distinct imaging phenotypes in HCM, distinguishing between overlapping presentations in different aetiologies. Abstract Figure 1

The alcohol-induced cardiomyopathy: A cardiovascular magnetic resonance characterization

BackgroundAlcoholic cardiomyopathy(ACM) is part of the non-ischaemic dilated cardiomyopathy(NI-DCM) spectrum. Little is known about cardiovascular magnetic resonance(CMR) features in ACM patients. The aim of this study is to describe CMR findings and their prognostic impact in ACM patients. MethodsConsecutive ACM patients evaluated in five referral CMR centres from January 2005 to December 2018 were enrolled. CMR findings and their prognostic value were compared to idiopathic NI-DCM(iNI-DCM) patients. The main outcome was a composite of death/heart transplantation/life-threatening arrhythmias. ResultsOverall 114 patients (52 with ACM and 62 with iNI-DCM) were included. ACM patients were more often males compared to iNI-DCM (90% vs 64%, respectively, p ≤ 0.001) and were characterized by a more pronounced biventricular adverse remodelling than iNI-DCM, i.e. lower LVEF (31 ± 12% vs 38 ± 11% respectively, p = 0.001) and larger left ventricular end-diastolic volume (116 ± 40 ml/m2 vs 67 ± 20 ml/m2 respectively, p < 0.001). Similarly to iNI-DCM, late gadolinium enhancement (LGE), mainly midwall, was present in more than 40% of ACM patients but, conversely, it was not associated with adverse outcome(p = 0.15). LGE localization was prevalently septal (87%) in ACM vs lateral in iNI-DCM(p < 0.05). Over a median follow-up of 42 months [Interquartile Range 24–68], adverse outcomes were similar in both groups(p = 0.67). ConclusionsACM represents a specific phenotype of NI-DCM, with severe morpho-functional features at the onset, but similar long-term outcomes compared to iNI-DCM. Despite the presence and pattern of distribution of LGE was comparable, ACM and iNI-DCM showed a different LGE localization, mostly septal in ACM and lateral in iNI-DCM, with different prognostic impact.

Incidence of outflow tract ventricular tachycardia long after surgical aortic valve replacement.

BackgroundThe peri‐outflow tract region could be the origin of ventricular tachycardia (VT) after aortic valve replacement (AVR). However, the clinical characteristics of outflow tract ventricular tachycardias (OTVTs) after AVR are yet to be clarified. This study investigated the incidence, risk factors, and clinical characteristics of patients with OTVTs after AVR.MethodsWe retrospectively analyzed the clinical course of 120 patients who had undergone surgical AVR (SAVR) between April 1980 and October 2018. The patients had no ischemic or diagnosed cardiomyopathies other than primary aortic valve diseases.ResultsSix patients (5.0%) developed OTVTs after SAVR. The average onset was at 10.8 ± 5.7 years after SAVR. All cases of VT arose from the inferior axis and included left and right bundle branch block configuration. Two patients who underwent cardiac magnetic resonance imaging (MRI) had late gadolinium enhancement (LGE) in the midlayer of the left ventricle basal anteroseptal wall. Patients with periaortic VTs had significantly larger left ventricular (LV) diameter at systole, lower LV ejection fraction, higher positive rates of signal‐averaged electrocardiogram (SAECG), and nonsustained VTs on Holter monitoring. On ablation, local fragmented potentials with low voltage zones were observed in accordance with the LGE distribution. Multiple VTs originating from the periaortic region were provoked in the sessions.ConclusionsAcute OTVT was found in 5% of patients after SAVR. Arrhythmia risk stratification by SAECG, Holter ECG, and cardiac MRI should be considered for a long period in patients after SAVR.