Myocardial Biopsy Research Articles

Systemic Lupus Erythematosus Complicated by Dilated Cardiomyopathy and Severe Heart Failure: A Case Report

Systemic lupus erythematosus (SLE), a connective tissue disease characterized by the production of autoantibodies, can affect all organ systems. Cardiac involvement in patients with systemic lupus erythematosus (SLE) has been documented since the early 20th century. The manifestations may be diverse and may affect any portion of the heart, including the pericardium, the conduction system, the myocardium, the valves, and the coronary arteries. The incidence of cardiomyopathy associated with systemic lupus erythematosus (SLE) that is clinically manifested is rare; the majority of studies have indicated a prevalence of approximately 10%. Echocardiography has offered insights into cardiac anatomy and function in patients with systemic lupus erythematosus (SLE), with and without cardiac involvement. Endomyocardial biopsy is considered as the gold standard for diagnosis; however, its low sensitivity and risk of complications have limited its application. Cardiac magnetic resonance (CMR) imaging offers a promising alternative to myocardial biopsy. We present the case of a 57-year-old female with a history of lupus since 2010, who presented with an acute inaugural decompensation of dilated cardiomyopathy, with a left ventricular ejection fraction (LVEF) of 28%.

Free Immunoglobulin Light Chains in Patients With Myocarditis: a New Biomarker of Inflammation and Heart Failure

To study the concentration of immunoglobulin free light chains (FLCs) in patients with myocarditis in comparison with non-inflammatory heart diseases, their relationship with inflammatory markers and the severity of chronic heart failure (CHF). This study included 77 patients (31 women, mean age 54.1±13.3 years): 41 patients with myocarditis verified by myocardial biopsy (n=18) or using a noninvasive diagnostic algorithm, 31 patients with noninflammatory CHF (comparison group), and 5 patients with monoclonal gammopathy identified during the study (4 of them were diagnosed with AL amyloidosis with heart damage). In the myocarditis group, CHF was diagnosed in 29 patients, mean stage IIA, functional class (FC) 2-3, with a mean left ventricular ejection fraction 43%. In the comparison group, patients had predominantly IIA stage, FC 2-3 CHF without systolic dysfunction. The blood concentration of kappa and lambda FLC types was measured with Cloneus S-FLC-K TIA Kit and Cloneus S-FLC-L TIA Kit. Concentrations were considered normal at FLC-kappa 4.84-14.20 mg/l, FLC-lambda 7.03-22.50 mg/l, and the FLC-kappa/lambda ratio 0.426-1.050. Increased FLC concentrations were found in 58% of patients with myocarditis and in 77% of patients in the comparison group. The FLC-lambda concentration was significantly higher in the comparison group; there were no significant differences between the groups in FLC-kappa and their ratio. The closest significant correlations in both groups and the entire cohort were noted between FLCs of either type and CHF, as well as the requirement for loop diuretics (correlation coefficients, 0.60-0.90), independent on the severity of systolic dysfunction. Myocarditis patients also showed correlations of FLCs with the titer of antibodies to cardiomyocyte nuclear antigens, levels of C-reactive protein, leukocytes, neutrophils, erythrocyte sedimentation rate, and the concentration of N-terminal fragment of brain natriuretic peptide. In a subgroup of 10 myocarditis patients who were treated with immunosuppressants, FLCs of both types were significantly lower than in the comparison group; only with the persistence of severe CHF was an increase in FLCs noted. An increased FLC concentration can be considered as an important pathogenesis component that reflects both the specific mechanisms of myocarditis and the severity of CHF. In the absence of a statistically significant increase in general inflammatory markers in the blood of myocarditis patients, the measurement of FLCs can be used as an additional diagnostic marker and predictor of the decompensated variant of the course of myocarditis. However, the diagnostic and prognostic significance of FLC concentration in patients without CHF requires a further study.

Cryo-X-Ray Phase Contrast Imaging Enables Combined 3D Structural Quantification and Nucleic Acid Analysis of Myocardial Biopsies.

Snap-frozen biopsies serve as a valuable clinical resource of archival material for disease research, as they enable a comprehensive array of downstream analyses to be performed, including extraction and sequencing of nucleic acids. Obtaining three-dimensional (3D) structural information before multi-omics is more challenging but can potentially allow for better characterization of tissues and targeting of clinically relevant cells. Conventional histological techniques are limited in this regard due to their destructive nature and the reconstruction artifacts produced by sectioning, dehydration, and chemical processing. These limitations are particularly notable in soft tissues such as the heart. In this study, the feasibility of using synchrotron-based cryo-X-ray phase contrast imaging (cryo-X-PCI) of snap-frozen myocardial biopsies is assessed and 3D structure tensor analysis of aggregated myocytes, followed by nucleic acid (DNA and RNA) extraction and analysis. It is shown that optimal sample preparation is the key driver for successful structural and nucleic acid preservation which is unaffected by the process of cryo-X-PCI. It is proposed that cryo-X-PCI has clinical value for 3D tissue analysis of cardiac and potentially non-cardiac soft tissue biopsies before nucleic acid investigation.

Computed tomography-derived myocardial extracellular volume: a diagnostic marker for cardiac amyloidosis in transcatheter aortic valve implantation patients with biopsy confirmation

Abstract Background Transthyretin cardiac amyloidosis (ATTR-CA) appears to be prevalent in aortic stenosis (AS). The coexistence of ATTR-CA and severe AS is associated with an increased risk of hospitalization for heart failure after transcatheter aortic valve implantation (TAVI). The identification of ATTR-CA is of great clinical importance. In this study, we investigated the diagnostic value of computed tomography-derived myocardial extracellular volume (CT-ECV) for the diagnosis of biopsy-proven ATTR-CA. Methods From December 2022 to January 2024, we enrolled patients who underwent both TAVI and myocardial biopsy. CT-ECV was measured as part of routine CT imaging before TAVI and myocardial biopsy for definitive diagnosis of CA. Results Of 131 TAVI patients, 101 patients underwent myocardial biopsy. Eight patients (7.9%) were diagnosed with ATTR-CA. There were no significant differences in electrocardiographic parameters. On echocardiography, left ventricular ejection fraction (64 ± 16% vs. 65 ± 14%, p = 0.84) was similar between the 2 groups, whereas intraventricular septum and left ventricular posterior wall in diastole were thicker in the ATTR-CA group (15 ± 3mm vs. 13 ± 2mm, p = 0.04 and 14 ± 3mm vs. 12 ± 2mm, p <0.01, respectively). Significantly higher CT-ECV values were found in the ATTR-CA group than in the non-ATTR-CA group (32.6 ± 3.7% vs. 28.1 ± 3.7%, p = 0.001). Conclusions Patients with biopsy-proven ATTR-CA had high CT-ECV values. Routine CT-ECV evaluation before TAVI may be useful for the diagnosis of ATTR-CA.

Residual post-infarct myocardial inflammation detected by 68Ga-DOTATATE PET/MRI predicts long-term adverse cardiac remodelling

Abstract Background Maladaptive inflammatory responses are associated with adverse cardiac remodelling after myocardial infarction (MI), but clinical methods for detecting residual myocardial inflammation post-MI are lacking. Purpose To investigate somatostatin receptor subtype 2 (SST2) positron emission tomography (PET)/magnetic resonance imaging (MRI) using 68Ga-DOTATATE after MI. Methods In a prospective observational cohort study, infarct-related myocardial inflammation detected by 68Ga-DOTATATE PET at 2wk and 3mo post-MI was compared with MRI characteristics including left ventricular (LV) volumetric changes at 1yr, as well circulating immune cell phenotyping and serum proteomic markers. Patients with a prior history of MI or heart failure were excluded. Histological SST2 expression was assessed in myocardial biopsies. Results 38 participants (mean age 60 [SD 9] years; 84% male) with recent MI were enrolled, of whom 58% had an ST-segment elevation MI. Mean peak Troponin I was 16,665 (range 408 to >25,000) ng/L and mean post-infarct LV ejection fraction was 51 (SD 9) %. 68Ga-DOTATATE maximum standardized uptake values (SUVmax) at 10 (SD 4) days accurately localised infarcted myocardial segments defined by late-gadolinium enhancement MRI (LGE; Fig. 1); were 14.2% higher in akinetic/hypokinetic vs. normo-kinetic segments (p<0.0001); and were correlated both with peak segmental strain (r=0.47, p=0.003) and segmental T1 values (r=0.51, p=0.02). Mean infarct SUVmax was 19.7% lower on repeat PET/MRI after a mean 102 (SD 22) days (p<0.0001), and this change was in keeping with parallel reductions in T2-weighted oedema signal on MRI and serum biomarkers of cardiac injury and systemic inflammation. Residual inflammation assessed by mean infarct SUVmax at 3mo was correlated with ΔLV indexed end-diastolic volume at 369 (SD 14) days, after adjustment for baseline infarct size and other clinical variables (p=0.038). The 3mo:2wk ratio of mean infarct SUVmax was an even stronger predictor of adverse myocardial remodelling (p=0.0025). Circulating SST2+ classical monocytes were correlated with infarct 68Ga-DOTATATE signal (r=0.47, p=0.02), and SST2 was co-expressed with CD68+ macrophages in inflamed myocardial specimens of patients with recent MI and ischaemic heart failure. After statistical feature selection and multiple comparisons adjustments, among the blood markers associated with 3mo:2wk infarct SUVmax was CCL25, a chemokine involved in macrophage recruitment which has been implicated in adverse cardiac remodelling. Conclusions Here, in the first prospective clinical study of serial SST2 PET/MRI after MI, we show that 68Ga-DOTATATE can identify and track resolving infarct-related myocardial inflammation. Moreover, residual inflammation detected by 68Ga-DOTATATE is associated with long-term adverse myocardial remodelling and could provide a potential future imaging biomarker to help stratify high-risk patients for emerging immunomodulatory therapies.Figure 1.68Ga-DOTATATE PET-MRI after MI

Immune-checkpoint myocarditis phenotype when using systematic troponin surveillance in cancer patients.

Abstract Background ICI myocarditis, often described as potentially fulminant in registries from specialized centers, lacks sufficient data on its subclinical forms. ESC 2022 guidelines advocate systematic troponin measurements for early detection, resulting in numerous suspected cases of ICI myocarditis. Additionally, many patients receive other potentially cardiotoxic cancer drugs (e.g.,anthracyclines), adding complexity to the management. Purpose To identify factors associated with ICI-myocarditis diagnosis in a single-center unselected cohort referred for suspicion of CV immune-related adverse events(irAEs). Patients underwent standardized evaluation, including serum testing, ECG, echocardiogram, cardiac MRI(CMRi) and multidisciplinary team assessment including cardiology and internal medicine specialists. Coronary imaging and myocardial biopsy (EMB) were performed as needed. ICI-myocarditis diagnosis was adjudicated by expert panel (FC, MM, SH) based on Dallas, ESC, and IC-OS criteria. Results We enrolled 175 consecutive patients from March 2022 to October 2023; 40 (22.89%) were male, with a median age of 61 (IQR 48.0-72.0) years. 92(52.57%) were referred for lone asymptomatic troponin raise, 101 (57.7%) had breast cancer; 142 (81.11%) received other cardiotoxic drugs. We identified 95 (61.71%) patients with CV irAEs at referral (8 had >=2 CV irAEs) with a total of 108 CV irAEs after follow up, including 72 (41.14%) with ICI-myocarditis at referall. No CV deaths occurred within 30 days from referall. Characteristics and univariate analysis are depicted in the Table1. Reasons for referral in the ICI-myocarditis population are depicted in the Figure1. On multivariate regression analysis, prior CV disease history (OR 6.232 [CI 1.204-32.260], p=0.029), EMB (OR 24.969 [5.139-121.32], p=<.0001), IC-OS criteria fulfilled (OR 43.108 [9.222-201.510], p=<.0001), and positive Lake Louise criteria on CMRi (OR 6.583[1.416-30.610], p=0.0163) were associated with myocarditis. In a sub-analysis group of breast cancer patients (largely receiving anthracyclines), ICI-myocarditis was associated on multivariate regression with abnormal ECG (OR 14.227 [CI 1.632-124.040], p=< 0.0163) and EMB (OR 8.508 [CI 2.718-26.638], p=0.0002). The same characteristics were significantly associated with other CV irAEs in the group of breast cancer patients. In the group of patients with cancers other than breast, factors significantly associated with ICI myocarditis diagnosis were: EMB (OR 70.656 [CI 5.970-836.161], 0.0007), and no arterial hypertension (OR 9.554 [CI 1.792-50.940], p= 0.0082). Conclusions The FAST TRACK study highlights the high proportion of patients fulfilling ICI-myocarditis criteria despite no or mild symptoms, mainly referred for troponin elevation. However, subclinical ICI-myocarditis appears to bear good prognosis. Endomyocardial biopsy is key to increase the diagnosis rate of ICI-myocarditis across different cancer populations when mildly symptomatic.Table 1Figure 1

Significant correlation between the extent of myocardial fibrosis and heart failure parameters in patients undergoing transcatheter aortic valve implantation

Abstract Background Recent studies have demonstrated that the prognosis of patients undergoing transcatheter aortic valve implantation (TAVI) is determined by the presence of myocardial fibrosis. The aim of this study was to quantify myocardial fibrosis in tissues obtained through myocardial biopsy before TAVI and to evaluate the relationship between the extent of myocardial fibrosis and baseline cardiac parameters. Methods We performed a retrospective single-center study, including 93 patients who underwent cardiac biopsies before TAVI from December 2022 to December 2023. The extent of myocardial fibrosis was assessed on Masson’s trichrome-stained tissue specimens, using a validated software "ImageJ". Results Median percent area of myocardial fibrosis in the entire cohort was 4.7% (interquartile range: 2.5 - 7.9). A significant correlation was found between the extent of myocardial fibrosis and brain natriuretic peptide (r= 0.41 p=0.0001), left ventricular ejection fraction (r=0.34, p=0.0009), aortic valve area index (r=0.33, p=0.0017), and global longitudinal strain (r=0.52, p<0.001). Patients who experienced prior heart failure hospitalization had a significantly larger extent of myocardial fibrosis (3.3% vs. 7.0%, p=0.0002). Conclusions Extensive myocardial fibrosis was associated with various heart failure parameters in patients undergoing TAVI. Patients with a large extent of myocardial fibrosis may require early intervention and/or intensive heart failure medical therapy to prevent fibrosis progression.

Cardiac magnetic resonance T1 imaging for the diagnosis of cardiac amyloidosis among patients with symptomatic heart failure

Abstract Background Cardiac amyloidosis (CA) is a significant cause of heart failure in elderly patients. However, specific signs in cardiac imaging are lacking, hence bone scintigraphy in combination with screening for monoclonal protein, or myocardial biopsy is required for the diagnosis. Cardiac magnetic resonance (CMR) imaging with T1 mapping is a promising diagnostic tool, which may allow to differentiate causes of left ventricular (LV) hypertrophy, particularly CA. Purpose The aim of this study was to test the diagnostic accuracy of T1 mapping for the diagnosis of CA in elderly patients with symptomatic heart failure and red flags for CA. Methods We prospectively enrolled 120 patients aged above 60 years with symptomatic heart failure NYHA II-IV, LV ejection fraction ≥ 40%, increased LV wall thickness of ≥ 12 mm end-diastolic on echocardiography, and elevated cardiac biomarkers (N-terminal pro-B-type natriuretic peptide (NT-proBNP) ≥ 1,000 ng/L, high-sensitivity cardiac troponin T (hs-cTnT) ≥ 14 ng/L). All patients underwent standardized quantitative CMR with a 3.0T scanner. 99mTc-DPD bone scintigraphy, blood screening for monoclonal protein, and, where applicable, cardiac biopsy, were performed as reference methods in all patients. Primary endpoint was diagnostic accuracy of native T1 mapping for the diagnosis of CA. Results 112 patients were included in the final analysis. Median age was 81.0 years (interquartile range 74.0–85.0 years), and 45% were female. CA was diagnosed in 38 patients (34%), of which 32 suffered from a Transthyretin (ATTR) and 6 patients from light chain (AL) amyloidosis. The areas under the receiver operating characteristic curves for native T1 were 0.713, 0.772, 0.836 for global, septal short-axis (SAX), and septal 4-chamber (4Ch) view measurements. The corresponding value of extracellular volume fraction (ECV) was 0.904 (Figure 1). Based on these results, we developed a new diagnostic algorithm for the diagnosis of CA including T1 septal 4Ch and ECV, with a sensitivity and positive predictive value of both 92.9% and a specificity and negative predictive value of 95.8% (Figure 2). Thereby, contrast application can be avoided in 33% of patients. A definite diagnosis could be provided in 81%. Conclusion CMR with T1 imaging provides a high diagnostic accuracy to diagnose CA in patients with symptomatic heart failure at risk for CA. These data may help to identify underlying causes in heart failure which require specific treatment. An earlier diagnosis of CA may improve outcome of these patients.Figure 1Figure 2

Machine learning methods for diagnostic disease prediction and treatment decisions in parvovirus B19 positive viral cardiomyopathy

Abstract Background Parvovirus B19 (B19V) is the most common type of virus found in endomyocardial biopsies (EMB) from patients with inflammatory heart disease. However, the detection of genomic B19V-DNA appears to have little clinical significance and is often considered an incidental finding. Recent analyses of a large cohort of B19V-positive patients revealed that the detection of RNA transcripts rather than DNA is of clinical importance, as B19V-RNA-positive patients have a significantly worse cardiovascular outcome. Here, we applied machine learning (ML) methods to assess the impact of B19V transcriptional activity on cardiac inflammation and patient clinical outcome. Methods and results A total of 305 patients with a known clinical course and a positive endomyocardial B19V-DNA test were included in this study. Follow-up measurements of the B19V-specific transcripts VP1/2 and NS1 revealed significantly worse clinical courses than in patients without B19V-RNA detection (P=0.019, hazard ratio (95% CI)=1.62 (1.10-2.57)). LVEF at follow-up was significantly lower in patients with detected B19V-RNA (P=0.007), and adverse events such as worsening LV function (P=0.003) or stable systolic dysfunction (P=0.013) were more frequent in this group. Importantly, analysis of inflammatory markers in EMB showed no difference in patients with and without RNA detection (P=0.432), suggesting that the deterioration in clinical outcome was related to B19V transcriptional activity rather than an increase in inflammation. The analysis of area under the receiver operating characteristic curve (AUROC) of B19V-RNA-negative patients revealed that the macrophage marker MAC-1 (AUROC=0.66, P=0.002) was the single most prognostically relevant parameter, while the T cell marker CD3 (AUROC=0.73, P<0.001) was identified as the most prognostically relevant marker in B19V-RNA-positive patients. The linear combination of several inflammatory markers increased the AUROC value to 0.67 in B19V-RNA-negative patients and to 0.74 in B19V-RNA-positive patients. To further increase prognostic accuracy, we trained ML models on features derived from EMB inflammatory markers. For the prediction of major adverse cardiac events within 60 months, the best ML-models achieved an AUROC of 0.87 in B19V-RNA-positive and of 0.86 in B19V-RNA-negative patients, while models that neglect the differentiation of patients with regard to the presence of B19V RNA transcripts only achieved an AUROC of up to 0.76. Conclusions These results show that B19V transcriptional activity is an independent risk marker for adverse cardiac events in patients with viral cardiomyopathy and thus confirm the clinical-therapeutic importance of myocardial biopsy. Furthermore, we present an ML-based algorithm that accurately indicates disease progression in B19V-positive cardiomyopathy patients and is thus helpful for appropriate therapy recommendation.

Unraveling Marfan hearts: ultrastructural evidence for myocardial remodeling and cardiomyopathy

Abstract Background Despite improved life expectancy for patients with Marfan syndrome (MFS), significant morbidity and mortality persist. Although primarily attributed to aortic dissection and rupture, recent studies highlight the emerging role of arrhythmias and heart failure as additional contributors to morbidity and mortality in MFS. While severe valvular heart disease is an established cause of heart failure, there is a growing recognition of primary cardiomyopathy in patients with MFS. The mechanisms underlying cardiomyopathy in MFS remain poorly understood. Purpose This study aimed to reveal insights into the ultrastructural myocardial architecture in patients with MFS, thereby elucidating the role of cardiomyopathy in MFS. Methods This study enrolled 44 patients who underwent cardiac surgery at 2 centers (Marfan syndrome patients n=27 (MFS), ascending thoracic aortic aneurysm repair patients n=5 (non-MFS), patients post-orthotopic heart transplant n=12 (controls)). Myocardial biopsy samples were subjected to histopathological analysis using transmission electron microscopy and conventional histology. Results Conventional histological analysis revealed subtle abnormalities in the cardiomyocyte morphology of MFS patients, compared to non-MFS and controls. Overall, a slight increase in interstitial fibrosis and mild myocyte hypertrophy were observed in MFS patients. Ultrastructural examination of both MFS and non-MFS patients revealed significant structural remodeling and degenerative changes in the myocardium. These changes included: extensive myofibril lysis, compromised cell membrane integrity and nuclear chromatin condensation. Degenerative lesions were often accompanied by cytoplasmic debris, lysosomal residual bodies, autophagic vacuoles, and severe mitochondrial pathology. Dense accumulation of glycogen granules and lipofuscin was evident in areas of focal myofibril lysis. Notably, only MFS patients exhibited recruitment of granulocytes, including mast cells, eosinophils and neutrophils. A subset of MFS patients displayed advanced stages of myocardial degeneration. However, these changes did not correlate with clinical myocardial failure. Conclusions To the best of our knowledge, this study represents the first evidence of ultrastructural changes in the myocardium of patients with MFS. Our data indicate various degenerative changes in the myocardial architecture, including structural and metabolic myocardial remodeling, along with inflammatory cell infiltration. We believe that our findings of ultrastructural lesions reflect the complexity of myocardial disease in MFS and emphasize the importance of careful surveillance for cardiomyopathy in MFS patients. Further studies are warranted to confirm whether the observed granulocyte influx is specific to MFS and to clarify its role in MFS myocardial disease pathophysiology.Graphical abstract

Comparative evaluation of approach sites in right ventricular biopsy: influence on complication rates, particularly conduction defects

Abstract Background Myocardial biopsy is an essential procedure for the diagnosis of myocarditis and cardiomyopathy. As specific treatment for secondary cardiomyopathies becomes available, EMB becoming increasingly important. Although the procedure can be performed safely at institutions familiar with the procedure, some institutions tend to hesitate to perform EMB because of procedural complications. In addition, complete right bundle branch block (CRBBB) is a complication of right ventricular biopsy (RV-EMB) that occurs at a certain rate. Therefore, Patient with complete left bundle branch block (CLBBB) often exibit reluctance to undergo RV-EMB due to the risk of complete atrioventricular block. Although there are two approaches to RV-EMB, transfemoral vein and trans-intracavitary vein, and each institution is familiar with its approach, no study has ever looked at the difference in complication rates, mainly complete right bundle branch block, due to the different approach sites for right ventricular biopsy. Aims This study aims to examine the differences in complication rates, mainly CRBBB, due to differences in the approach site of the RV-EMB procedure. Methods/Results The subjects were 338 consecutive patients who underwent RV-EMB at our hospital between January 2017 and December 2022. We performed a retrospective analysis of 274 cases, excluding 43 cases that were originally CRBBB and 21 cases with ventricular pacing, ventricular fibrillation (VF), complete atrioventricular block from beginning to end, and no pre- and post-ECGs. The transfemoral venous approach group (Group TF) included 96 cases and the transjugular venous approach (Group TJ) included 178 cases, with Group TF using more warfarin (13.5% vs. 3.4%, p=0.004) and obtaining fewer specimens compared to Group TJ (3.0±1.0 vs. 3.8±0.6 pieces, p<0.001). Transient CRBBB was present in 28 (29.2%) patients in Group TF and 12 (6.7%) patients in Group TJ (p<0.001); CRBBB persisted beyond 24 hours in 8 (8.3%) and 2 (1.1%) patients, respectively. There was one case of cardiac tamponade in Group TF and two cases of VF in Group TJ, but no cases of stroke, permanent pacemaker implantation, or death. Multivariate logistic regression analysis showed that the transfemoral approach and corticosteroid administration emerged as independent predictor in the occurrence of CRBBB (p<0.001, odds ratio 0.17 and p=0.021, odds ratio 3.76, respectively.), whereas in cases of sustained CRBBB, solely the transfemoral approach stood as an independent predictor (p=0.002, odds ratio 0.07). Conclusions In RV-EMB, the transjugular venous approach has the potential to decrease CRBBB as a complication. The transjugular vein approach may be preferable in cases where complete AV block is a concern, such as patients who originally have CLBBB.

Anti-SRP Antibodies and Myocarditis in Systemic Sclerosis Overlap Syndrome with Immune-Mediated Necrotizing Myositis (IMNM)

Overlap syndrome of systemic sclerosis and idiopathic inflammatory myopathies is an increasingly frequent entity, but the association with immune-mediated necrotizing myositis has rarely been described. While myositis or myopathy may be features of scleroderma, it is imperative to correctly diagnose an overlap syndrome of these two, since it can be considered a different entity with specific management and a worse prognosis. Anti-signal recognition particle (anti-SRP) antibodies target the striated muscle fiber and inhibit myoblast regeneration, resulting in myofiber atrophy and necrosis. Anti-SRP antibodies are specific in immune-mediated necrotizing myopathy characterized by myonecrosis and minimal inflammatory reaction, with proximal muscle weakness and typical extra-muscular manifestation. There are controversial data on the association of cardiac manifestations and the presence of these antibodies, and recent studies cannot prove a significant correlation between the two. Myocarditis is a complication with an unpredictable, potentially severe outcome from heart failure and dilated cardiomyopathy to fatality. It can be difficult to diagnose, and a myocardial biopsy can be problematic in daily practice; thus, most practitioners rely on cardiac magnetic resonance with suggestive images for the correct diagnosis. This paper seeks to address the challenges associated with the diagnosis and treatment of collagen diseases by evaluating the role of anti-SRP antibodies in the pathogenesis of cardiac involvement.

Myocardial inflammatory cells in cardiac amyloidosis

Background: Immunoglobulin derived AL amyloidosis and transthyretin derived ATTR amyloidosis are the most common forms of cardiac amyloidosis. Both may present with cardiac arrhythmias, heart failure, and extracardiac symptoms. Disease outcome is often fatal. Recently, it was proposed that amyloid may cause cardiac inflammation. Here we tested the hypothesis that immune cell infiltration in cardiac tissue correlates with clinicopathological patient characteristics. Patients and methods: Myocardial biopsies from 157 patients with cardiac amyloidosis (46.5% AL, 53.3% ATTR) were immunohistochemically assessed for the presence and amount of T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO). Amyloid load, cardiomyocyte diameter, apoptosis (Caspase 3), necrosis (complement 9), and various clinical parameters were assessed and correlated with immune cell density. Results: Myocardial tissue was infiltrated with T lymphocytes (CD3), macrophages (CD68) and neutrophils (MPO) with variable amounts. Significant correlations were found between the number of macrophages and NYHA class. No correlations were found between the presence and amount of T lymphocytes, neutrophils and clinicopathological patient characteristics. Conclusion: The significant correlation between cardiac macrophage density and heart failure points towards a significant role of macrophages in disease pathology.

A novel bailout technique using myocardial biopsy forceps to grasp a dislodged angio-seal collagen with footplate

BackgroundHemostatic devices are now frequently used in femoral artery punctures, and the Angio-Seal (Terumo, Tokyo, Japan) is one of the most commonly used devices for closure of the femoral artery because it provides rapid hemostasis. Although device failure rarely occurs, if the collagen falls into the femoral artery, it may lead to severe limb ischemia. Herein, we describe a case of a novel endovascular technique for the treatment of Angio-Seal arterial closure device failure.Case presentationThe patient in Case 1 was a 75-year-old man with severe left limb claudication. We used a contralateral antegrade approach and used the Angio-Seal for hemostasis. However, the Angio-Seal collagen and footplate dropped and stopped at the bifurcation of the superficial femoral artery and deep femoral artery. The collagen with the footplate was caught with myocardial biotome forceps (MBF) and pulled into the external iliac artery (EIA). The distal common femoral artery (CFA) was punctured, and we delivered a 10.0- × 80-mm stent (SMART®; Cordis, USA) to the EIA from the ipsilateral sheath. The stent was deployed at the EIA and crushed the collagen. The patient in Case 2 was an 88-year-old man with rest pain in the right limb. The right CFA was punctured using an ipsilateral approach and the Angio-Seal was used for hemostasis. The Angio-Seal collagen with the footplate dropped into the bifurcation of the deep femoral artery. The collagen and footplate were caught with MBF and pulled up to the EIA. The right CFA was punctured and a 10.0- × 60-mm stent (SMART®; Cordis) was delivered from the ipsilateral sheath. The stent was deployed at the EIA and crushed the collagen with the footplate.ConclusionsMBF were used to grasp the dislodged collagen with the anchor and cover it with a stent at the iliac artery. This may be a useful bailout technique for Angio-Seal dislodgement.

Improved diagnostic performance of high-sensitivity cardiac troponins in muscle dystrophies using comprehensive definition criteria for cardiac involvement: A longitudinal study on 35 patients.

Sparse information is available on the correct interpretation of elevated high-sensitivity cardiac troponin (hs-cTn) in confirmed muscular dystrophies. Serum concentrations of hs-cTn T (hs-cTnT) and hs-cTn I (hs-cTnI) were determined in 35 stable outpatients with confirmed skeletal muscle dystrophies. We calculated sensitivities, specificities, and positive and negative predictive values of hs-cTnT and hs-cTnI for identification of cardiac involvement using a comprehensive definition that included diastolic left ventricular and right ventricular function, strain analysis using two-dimensional transthoracic echocardiogram and magnetic resonance imaging, myocardial biopsies, and consideration of a variety of triggers for cardiac injury, including arrhythmias, conduction disorders, and hypoxemia due to respiratory failure. Cardiac involvement was diagnosed in 34 of 35 cases. Specificities of hs-cTnT increased from 12.5% to 100% (p = 0.0006) applying the comprehensive definition compared to a definition based on electrocardiography and echocardiography alone. At the recommended 99th percentile upper limit of normal, sensitivities were significantly lower for hs-cTnI than for hs-cTnT (29.4% vs. 100%, p = 0.0164). Conversely, the specificities of hs-cTnT and hs-cTnI increased to 100% when using the comprehensive definition criteria for diagnosing cardiac involvement. Elevated hs-cTnT but not hs-cTnI discriminates cardiac involvement in cases with confirmed skeletal muscle dystrophies with very high sensitivity and 100% specificity. Prior reports on worse performance may be explained by the use of less sensitive imaging methods or incomplete assessment of cardiac involvement.

Multi-modality artificial intelligence-based transthyretin amyloid cardiomyopathy detection in patients with severe aortic stenosis.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a frequent concomitant condition in patients with severe aortic stenosis (AS), yet it often remains undetected. This study aims to comprehensively evaluate artificial intelligence-based models developed based on preprocedural and routinely collected data to detect ATTR-CM in patients with severe AS planned for transcatheter aortic valve implantation (TAVI). In this prospective, single-center study, consecutive patients with AS were screened with [99mTc]-3,3-diphosphono-1,2-propanodicarboxylic acid ([99mTc]-DPD) for the presence of ATTR-CM. Clinical, laboratory, electrocardiogram, echocardiography, invasive measurements, 4-dimensional cardiac CT (4D-CCT) strain data, and CT-radiomic features were used for machine learning modeling of ATTR-CM detection and for outcome prediction. Feature selection and classifier algorithms were applied in single- and multi-modality classification scenarios. We split the dataset into training (70%) and testing (30%) samples. Performance was assessed using various metrics across 100 random seeds. Out of 263 patients with severe AS (57% males, age 83 ± 4.6years) enrolled, ATTR-CM was confirmed in 27 (10.3%). The lowest performances for detection of concomitant ATTR-CM were observed in invasive measurements and ECG data with area under the curve (AUC) < 0.68. Individual clinical, laboratory, interventional imaging, and CT-radiomics-based features showed moderate performances (AUC 0.70-0.76, sensitivity 0.79-0.82, specificity 0.63-0.72), echocardiography demonstrated good performance (AUC 0.79, sensitivity 0.80, specificity 0.78), and 4D-CT-strain showed the highest performance (AUC 0.85, sensitivity 0.90, specificity 0.74). The multi-modality model (AUC 0.84, sensitivity 0.87, specificity 0.76) did not outperform the model performance based on 4D-CT-strain only data (p-value > 0.05). The multi-modality model adequately discriminated low and high-risk individuals for all-cause mortality at a mean follow-up of 13 months. Artificial intelligence-based models using collected pre-TAVI evaluation data can effectively detect ATTR-CM in patients with severe AS, offering an alternative diagnostic strategy to scintigraphy and myocardial biopsy.

Cardiomyocyte-derived circulating extracellular vesicles allow a non-invasive liquid biopsy of myocardium in health and disease.

The ability to track disease without tissue biopsy in patients is a major goal in biology and medicine. Here, we identify and characterize cardiomyocyte-derived extracellular vesicles in circulation (EVs; "cardiovesicles") through comprehensive studies of induced pluripotent stem cell-derived cardiomyocytes, genetic mouse models, and state-of-the-art mass spectrometry and low-input transcriptomics. These studies identified two markers (POPDC2, CHRNE) enriched on cardiovesicles for biotinylated antibody-based immunocapture. Captured cardiovesicles were enriched in canonical cardiomyocyte transcripts/pathways with distinct profiles based on human disease type (heart failure, myocardial infarction). In paired myocardial tissue-plasma from patients, highly expressed genes in cardiovesicles were largely cardiac-enriched (vs. "bulk" EVs, which were more organ non-specific) with high expression in myocardial tissue by single nuclear RNA-seq, largely in cardiomyocytes. These results demonstrate the first "liquid" biopsy discovery platform to interrogate cardiomyocyte states noninvasively in model systems and in human disease, allowing non-invasive characterization of cardiomyocyte biology for discovery and therapeutic applications.

Cellular and extracellular proteomic profiling of paradoxical low-flow low-gradient aortic stenosis myocardium.

Patients with severe aortic stenosis (AS), low transvalvular flow (LF) and low gradient (LG) with normal ejection fraction (EF)-are referred to as paradoxical LF-LG AS (PLF-LG). PLF-LG patients develop more advanced heart failure symptoms and have a worse prognosis than patients with normal EF and high-gradient AS (NEF-HG). Despite its clinical relevance, the mechanisms underlying PLF-LG are still poorly understood. Left ventricular (LV) myocardial biopsies of PLF-LG (n = 5) and NEF-HG patients (n = 6), obtained during transcatheter aortic valve implantation, were analyzed by LC-MS/MS after sequential extraction of cellular and extracellular matrix (ECM) proteins using a three-step extraction method. Proteomic data are available via ProteomeXchange with identifier PXD055391. 73 cellular proteins were differentially abundant between the 2 groups. Among these, a network of proteins related to muscle contraction and arrhythmogenic cardiomyopathy (e.g., cTnI, FKBP1A and CACNA2D1) was found in PLF-LG. Extracellularly, upregulated proteins in PLF-LG were related to ATP synthesis and oxidative phosphorylation (e.g., ATP5PF, COX5B and UQCRB). Interestingly, we observed a 1.3-fold increase in cyclophilin A (CyPA), proinflammatory cytokine, in the extracellular extracts of PLF-LG AS patients (p < 0.05). Consistently, immunohistochemical analysis confirmed its extracellular localization in PLF-LG AS LV sections along with an increase in its receptor, CD147, compared to the NEF-HG AS patients. Levels of core ECM proteins, namely collagens and proteoglycans, were comparable between groups. Our study pinpointed novel candidates and processes with potential relevance in the pathophysiology of PLF-LG. The role of CyPA in particular warrants further investigation.

The oxytocin-oxytocin receptors system — a new pathogenetic mechanism in the development of diabetic phenotype of heart failure with preserved ejection fraction in women

Aim. To determine the pathogenetic role of the oxytocinergic system in the development of myocardium structural and functional changes in women with heart failure with preserved ejection fraction (HFpEF) associated with type 2 diabetes mellitus (DM2T) (diabetic phenotype of HFpEF).Material and methods. The study included 60 women aged 67.0±4.9 years with HFpEF stage I-IIA, FC I-III, 30 of them had DM2T who were admitted for elective coronary artery bypass grafting. The development of HFpEF is caused by coronary artery disease (CAD) and arterial hypertension (AH). Prior to surgery, all patients underwent a standard examination, blood levels of NT-proBNP, oxytocin (Ox), echocardiography were determined to find the types of left ventricular (LV) myocardial remodeling and diastolic dysfunction (DD). Myocardium biopsies of the right atrium auricle obtained during coronary bypass surgery were studied by microscopy, morphometry and immunohistochemistry (the expression of oxytocin receptors (OxR), a marker of proliferation ki-67).Results. According to echocardiography, eccentric LV hypertrophy (46.7/36.7%) and DD type 2 (47/17%, p=0.003) prevailed in the group of women with the diabetic phenotype of HFpEF. A higher content of NT-proBNP (480.72±241.87/434.46±282.78 ng/ml, p=0.06) and a lower concentration of Ox (102.11±35.89/320.37±294.71 pg/ml, p=0.0016) in blood serum were established, as well as an increase in the number of cardiomyocytes (CMC) with a high expression level OxR (63.69±19.47/12.16±23.09%, p=0.000) in patients with the diabetic phenotype of HFpEF. Negative associations were determined between the blood level of Ox and the CMC diameter (r=-0.10, p=0.020), the area of their cytoplasm (r=-0.16, p=0.000) and the area of the nuclei (r=-0.11, p=0.015) in patients of both groups. A decrease in Ox concentration in the blood of patients with diabetic phenotype of HFpEF was accompanied by an increase in the number of CMCs with a high level of OxR expression (r=-0.63, p=0.000).Conclusion. The study has shown the important involvement of oxytocinergic signaling pathways in the HFpEF pathogenesis. HFpEF associated with DM2T in women was characterized by more unfavorable structural and functional changes in the myocardium, a significant increase in the number of hypertrophied CMCs with a high level of OxR expression and Ox decrease in blood serum. The mechanisms of the first-established significant increase in the content of Ox in the blood of patients with HFpEF without diabetes and its significant decrease in patients with diabetic phenotype of HFpEF leading to more pronounced structural and functional changes in the myocardium, require further study.

Abstract Mo047: DNA METHYLATION AND TRANSCRIPTIONAL MARKERS OF MYOCARDIAL REVERSE REMODELING IN HF PATIENTS ON LVAD SUPPORT

Heart failure (HF) involves global genome modifications. Adverse structural and function remodeling that occurs in HF was initially considered to be irreversible. However, ~15% of HF patients on left ventricular assist device (LVAD) support show significant structural and functional reverse remodeling, distinguishing them as responders (R), while ~85% are non-responders (NR). DNA methylation and transcriptional changes that exert myocardial recovery is not well understood. To address this, we performed whole-genome bisulphite sequencing and RNA sequencing on paired myocardial biopsies from HF patients (n=84) before (pre-LVAD) and after LVAD unloading (post-LVAD). Post-LVAD samples showed activation of pathways including TGFβ signaling, PTEN and Fatty acid oxidation compared to pre. Integrating DNA methylation and transcriptomics data revealed hypomethylation (upregulation) of genes including Scaper, Frat1 and Magi1 and hypermethylation (downregulation) of Tpp3 and Icam. Overall, suggesting a unique ECM-specific stabilization pathway post-LVAD unloading. Segregating samples based on their response to LVAD unloading, pathways such as inflammation and fibrotic signaling were activated in postNR compared to preNR. Hypomethylation of Magi1 and hypermethylation of Tppp3 was observed in postNR suggesting cross-linking proteins and destabilization of microtubule formation as potential mechanisms of functional regression in NR. Conversly, postR showed activation of deubiquitination, oxidative phosphorylation and NLR signaling compared to preR. Finally, we observed integrin signaling, syndecan interaction, collagen degradation and wound healing pathways were activated in postR compared to postNR. Hypomethylation of actin cytoskeleton ( Myl12a ), microtubule/motor proteins ( Kif5b ) and tropomyosin ( Tpm3 ) were observed in postR, suggesting a plausible reverse remodeling mechanism mediated by ECM degradation and stabilization of myocardium in these patients. Western blot analysis also showed a trend towards an increase in collagen in postNR compared to postR (n=4, p=0.06). Finally, a mouse model of HF and recovery was used and pathways including ECM degradation and cardioprotective signaling were activated in mice that recovered from HF compared to mice that did not. Overall, our data suggests a unique ECM regulation pathway to contribute towards myocardial reverse remodeling in HF patients.