Early Myocardial Changes in Patients with Rheumatoid Arthritis without Known Cardiovascular Diseases—A Comprehensive Cardiac Magnetic Resonance Study

Clinically silent cardiac disease is frequently observed in rheumatoid arthritis (RA), and cardiovascular complications are the leading cause of mortality in RA. We sought to evaluate the myocardium of young RA patients without known cardiac disease using cardiac magnetic resonance (CMR), including T1/T2 mapping sequences. Eighteen RA patients (median age 41 years, 83% females) mainly with low disease activity or in remission and without any known cardiovascular disease were prospectively included to undergo CMR. A control group consisted of 10 sex- and age-matched patients without RA or any known structural cardiovascular disease. Heart chambers size and left/right ventricular systolic function were similar in patients with RA and controls. Signs of myocardial oedema were present in up to 39% of RA patients, including T2 time above cut-off value in 7 patients (39%) in comparison to none of the controls (p = 0.003) and T2 signal intensity ratio above the cut-off value in 6 patients (33%) and in none of the controls (p = 0.06). Extracellular volume was similar in both groups signifying a lack of diffuse fibrosis in studied group of RA patients. There were also no signs of late gadolinium enhancement (LGE) in either group except for one patient with RA who was found to have prior silent myocardial infarction. No correlation was found between markers of disease severity and markers of oedema observed on CMR in patients with RA. Nevertheless, patients with increased T2 time (≥50 ms) were more likely to have X-ray erosions (p = 0.02) and a longer duration between symptom onset and diagnosis (p = 0.02). Finally, there were no significant arrhythmias on 24-h ECG Holter monitoring in RA patients. CMR features of myocardial oedema without signs of myocardial fibrosis were found in 39% of young RA patients without known heart disease or cardiac symptoms. Presence of myocardial oedema was associated with X-ray erosions and a longer duration between symptom onset and diagnosis. The clinical significance of the observed early myocardial changes accompanying RA requires additional studies.

The Effects of Fibrotic Cell Type and Its Density on Atrial Fibrillation Dynamics: An In Silico Study

Remodeling in atrial fibrillation (AF) underlines the electrical and structural changes in the atria, where fibrosis is a hallmark of arrhythmogenic structural alterations. Fibrosis is an important feature of the AF substrate and can lead to abnormal conduction and, consequently, mechanical dysfunction. The fibrotic process comprises the presence of fibrotic cells, including fibroblasts, myofibroblasts and fibrocytes, which play an important role during fibrillatory dynamics. This work assesses the effect of the diffuse fibrosis density and the intermingled presence of the three types of fibrotic cells on the dynamics of persistent AF. For this purpose, the three fibrotic cells were electrically coupled to cardiomyocytes in a 3D realistic model of human atria. Low (6.25%) and high (25%) fibrosis densities were implemented in the left atrium according to a diffuse fibrosis representation. We analyze the action potential duration, conduction velocity and fibrillatory conduction patterns. Additionally, frequency analysis was performed in 50 virtual electrograms. The tested fibrosis configurations generated a significant conduction velocity reduction, where the larger effect was observed at high fibrosis density (up to 82% reduction in the fibrocytes configuration). Increasing the fibrosis density intensifies the vulnerability to multiple re-entries, zigzag propagation, and chaotic activity in the fibrillatory conduction. The most complex propagation patterns were observed at high fibrosis densities and the fibrocytes are the cells with the largest proarrhythmic effect. Left-to-right dominant frequency gradients can be observed for all fibrosis configurations, where the fibrocytes configuration at high density generates the most significant gradients (up to 4.5 Hz). These results suggest the important role of different fibrotic cell types and their density in diffuse fibrosis on the chaotic propagation patterns during persistent AF.

Personalized Computational Heart Models with T1-Mapped Fibrotic Remodeling Predict Risk of Sudden Death Risk in Patients with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) causes sudden cardiac death (SCD) due to ventricular arrhythmias (VA) manifesting from myocardial fibrosis proliferation. Current clinical risk stratification criteria inadequately identify at-risk patients in need of primary prevention of VA. Here, we use mechanistic computational modeling of the heart to analyze how HCM-specific remodeling of the heart promotes arrhythmogenesis and to develop a personalized strategy to forecast risk of VAs in these patients. We combine contrast-enhanced cardiac magnetic resonance (CMR) imaging and T1 mapping data to construct digital replicas of HCM patient hearts that represent the patient-specific distribution of focal and diffuse fibrosis and evaluate the substrate propensity to VA. Our analysis indicates that the presence of diffuse fibrosis, which is rarely assessed in these patients, increases arrhythmogenic propensity. In forecasting future VA events in HCM patients, the imaging-based computational heart approach achieved 84.6%, 76.9%, and 80.1% sensitivity, specificity, and accuracy, respectively, and significantly outperformed current clinical risk predictors. This novel VA risk assessment may have the potential to prevent SCD and help deploy primary prevention appropriately in HCM patients.

Cardiovascular outcomes in systemic sclerosis with abnormal cardiovascular MRI and serum cardiac biomarkers

ObjectivesTo explore the prognostic value of subclinical cardiovascular (CV) imaging measures and serum cardiac biomarkers in systemic sclerosis (SSc) for the development of CV outcomes of primary heart involvement (pHI).MethodsPatients with SSc with no clinical SSc-pHI and no history of heart disease underwent cardiovascular magnetic resonance (CMR) imaging, and measurement of serum high-sensitivity-troponin I (hs-TnI) and N-terminal-pro-brain natriuretic peptide (NT-proBNP). Follow-up clinical and CV outcome data were recorded. CV outcomes were defined as myocarditis, arrhythmia and/or echocardiographic functional impairment including systolic dysfunction and/or diastolic dysfunction.ResultsSeventy-four patients with a median (IQR) age of 57 (49, 63) years, 32% diffuse cutaneous SSc, 39% interstitial lung disease, 30% Scl70+ were followed up for median (IQR) 22 (15, 54) months. Ten patients developed CV outcomes, comprising one patient with myocarditis and systolic dysfunction and nine arrhythmias: three non-sustained ventricular tachycardia and six supraventricular arrhythmias. The probability of CV outcomes was considerably higher in those with NT-proBNP >125 pg/mL versus normal NT-proBNP (X2=4.47, p=0.035). Trend for poorer time-to-event was noted in those with higher extracellular volume (ECV; indicating diffuse fibrosis) and hs-TnI levels versus those with normal values (X2=2.659, p=0.103; X2=2.530, p=0.112, respectively). In a predictive model, NT-proBNP >125 pg/mL associated with CV outcomes (OR=5.335, p=0.040), with a trend observed for ECV >29% (OR=4.347, p=0.073).ConclusionThese data indicate standard serum cardiac biomarkers (notably NT-proBNP) and CMR indices of myocardial fibrosis associate with adverse CV outcomes in SSc. This forms the basis to develop a prognostic model in larger, longitudinal studies.

Risk stratification in cardiomyopathies (dilated, hypertrophic, and arrhythmogenic cardiomyopathy) by cardiac magnetic resonance imaging

Cardiac magnetic resonance imaging (CMR) is a non-invasive, multiplanar, and high spatial resolution imaging technique, which represents the current gold standard for the evaluation of biventricular volumes and function. Furthermore, unlike other methods, it has the great advantage of characterizing the myocardial tissue by identifying the presence of alterations, such as oedema and focal and diffuse fibrosis. In particular, the late gadolinium enhancement technique makes it possible to identify areas of focal fibrosis that often constitute the substrate for the triggering of threatening ventricular arrhythmias at the basis of sudden cardiac death. For this reason, the use of CMR in the study of cardiomyopathies has become of primary importance, both for the differential diagnosis and for patient risk stratification. In this brief review, the ability of CMR in prognostic stratification of patients with dilated, hypertrophic, and arrhythmogenic cardiomyopathy will be analysed. In particular, the role of CMR in the prediction of arrhythmic risk and in the decision-making process for the implantation of a cardiac defibrillator will be examined.

ACTIVITY OF ANGIOTENSIN-CONVERSING ENZYME-2 IN ACUTE PULMONARY INFLAMMATION

Relevance. Angiotensin converting enzyme-2 (ACE2), which is the gateway to coronavirus, is also an important component of the tissue renin-angiotensin system with a number of anti-inflammatory effects. It is known that ACE2 is expressed in the lungs of patients with coronavirus pneumonia, but it is not clear how this depends on the stages of development and the severity of inflammation. Objective: to establish the effect of acute inflammation on pulmonary expression of angiotensin-converting enzyme-2. Material and methods. In Wistar rats (n=20), in compliance with bioethical standards, a sterile nylon thread 2.5 cm long and 0.2 mm thick to a depth of 2.5 cm was introduced into the trachea. The animals were observed and removed from the experiment at 7, 14, 21 and 28 days, microscopic and immunohistochemical (monoclonal antibodies against ACE2; clone 4G5.1; EMD Millipore Corporation; Temecula, CA US) studies were performed. Results. The microscopic picture of the lungs indicated the development of acute bronchopulmonary inflammation during the first week, the formation of peribronchial and alveolar abscesses in the second week with the onset of resolution of bronchopneumonia with the organization of abscesses in the third week and the development of diffuse fibrosis of the parenchyma and vascular hyalinosis in the fourth week of observation. The exudative phase of acute inflammation was accompanied by inhibition of ACE2 activity in bronchial epithelial cells, type II alveolocytes and vascular endothelium. With the transition of inflammation to the stage of proliferation and fibrosis, ACE2 activity was restored. Conclusion. The detected phase change in ACE2 activity can cause a wavy recurrent course of coronavirus infection, since an increase in the amount of ACE2 protein during attenuation of acute inflammation contributes to an increase in target cell infection.

Immunoglobulin G4-related Ophthalmic Disease with Peripheral Eosinophilia and Elevated Immunoglobulin E Levels

Purpose: To report a case with peripheral eosinophilia and elevated immunoglobulin (Ig) E levels, subsequently diagnosed as IgG4-related ophthalmic disease involving the extraocular muscles.Case summary: A 56-year-old male visited the allergy department presenting with systemic urticaria and bilateral eyelid swelling that began 5 months prior. Laboratory examinations showed elevated levels of serum eosinophil and IgE, 1,309 IU/uL and 1,793 IU/mL, respectively. Orbital computed tomography revealed that all extraocular muscles and the bilateral exophthalmos were enlarged, and the patient was referred to the ophthalmology department. Eye alignment was orthophoric for all gaze directions, and limited abduction (-1) was noted in both eyes. An incisional biopsy of the extraocular muscles was conducted. Histopathological findings showed lymphoid aggregates, diffuse fibrosis, and an increased IgG4+/IgG+ plasma cell ratio of 40%, which led to the diagnosis of IgG4-related ophthalmic disease. An elevated IgG4 serum level (1,710 mg/dL) was also noted. The patient received high-dose intravenous steroids and eyelid swelling improved after two months. Levels of serum eosinophil, IgE, and IgG4 all decreased after three months.Conclusions: IgG4-related ophthalmic disease may be accompanied by eosinophilia and elevated IgE. These findings may facilitate future diagnoses of this disease.

Necrotizing descending mediastinitis by Acinetobacter Baumannii in an out-patient: a case report

Background Complicated cervico-facial cellulitis is an infectious disease which can have fatal prognosis. Necrotizing descending mediastinitis is a rare and fatal complication of cervico-thoracic cellulitis. This is the case of necrotizing descending mediastinitis complicating by a multi-resistant Acinetobacter Baumannii in a 27-year-old female, with early management of hemodynamic, respiratory and surgical emergencies, and very careful post-operative care, resulting in very satisfying outcome. Case presentation The patient presented was first treated with broad spectrum antibiotics for Ludwig’s angina for 10 days, then presented with a swelling of sub-mandibular, sub-mental, and cervical regions, a mild respiratory distress, with clinical enhancement of dyspnea in proclive position, tachycardia of 100 beats per minute, and arterial blood pressure of 10/5. Clinical exam showed a tight trismus, with oral opening inferior to 1 cm, no inflammatory signs in facial and cervical swollen areas, and a saturation of 95% in proclive position. Auscultation suspected a pericardial effusion. CT scan with and without injected contrast medium showed diffuse abscesses of sub-mental, sub-mandibular, retro-pharyngeal, para-pharyngeal regions, along with mediastinal abscesses and pericardial effusion. Trans-thoracic ultrasound showed 2 cm pericardial effusion, preserved function of myocardium, and without signs of tamponade. The diagnosis of necrotizing descending mediastinitis with pericardial effusion was established. The patient underwent a course of wide spectrum antibiotic therapy, low doses of cathecholamine, and a surgical drainage through cervical approach of all implicated zones. The surgical dissection was thorough and difficult due to diffuse fibrosis found in tissues of cervical regions. Two hundred milliliters of pus was evacuated, with a placement of surgical drains and Delbet blades. Bacteriological exam found an Acinetobacter Baumannii sensitive to colistin only. The post-operative outcome showed clinical and biological enhancement; however, a residual mediastinal collection appeared in control CT scan after 48 h, which indicated a surgical revision through mediastinoscopy. The post-operative outcome was satisfying with stabilized clinical, biological, and radiological aspects. Conclusions Necrotizing descending mediastinitis is an infectious disease correlated with a very elevated mortality rate, and management is based on airway control, antibiotic therapy, and surgical treatment, as well as the post-operative intensive unit care. Early diagnosis and appropriate management enhances outcome and decreases mortality significantly.

Characterization of Atrial Propagation Patterns and Fibrotic Substrate With a Modified Omnipolar Electrogram Strategy in Multi-Electrode Arrays

Introduction: The omnipolar electrogram method was recently proposed to try to generate orientation-independent electrograms. It estimates the electric field from the bipolar electrograms of a clique, under the assumption of locally plane and homogeneous propagation. The local electric field evolution over time describes a loop trajectory from which omnipolar signals in the propagation direction, substrate and propagation features, are derived. In this work, we propose substrate and conduction velocity mapping modalities based on a modified version of the omnipolar electrogram method, which aims to reduce orientation-dependent residual components in the standard approach.Methods: A simulated electrical propagation in 2D, with a tissue including a circular patch of diffuse fibrosis, was used for validation. Unipolar electrograms were calculated in a multi-electrode array, also deriving bipolar electrograms along the two main directions of the grid. Simulated bipolar electrograms were also contaminated with real noise, to assess the robustness of the mapping strategies against noise. The performance of the maps in identifying fibrosis and in reproducing unipolar reference voltage maps was evaluated. Bipolar voltage maps were also considered for performance comparison.Results: Results show that the modified omnipolar mapping strategies are more accurate and robust against noise than bipolar and standard omnipolar maps in fibrosis detection (accuracies higher than 85 vs. 80% and 70%, respectively). They present better correlation with unipolar reference voltage maps than bipolar and original omnipolar maps (Pearson's correlations higher than 0.75 vs. 0.60 and 0.70, respectively).Conclusion: The modified omnipolar method improves fibrosis detection, characterization of substrate and propagation, also reducing the residual sensitivity to directionality over the standard approach and improving robustness against noise. Nevertheless, studies with real electrograms will elucidate its impact in catheter ablation interventions.