Myocarditis Presenting Research Articles

Rare presentation of COVID-19 vaccine-induced myocarditis: A case report

Rare presentation of COVID-19 vaccine-induced myocarditis: A case report

Acute lymphocytic myocarditis presenting as complete heart block in an adult: a case report

BackgroundComplete heart block (CHB) as a first presentation of acute viral myocarditis is a rare occurrence associated with increased morbidity and mortality. In such cases, an endomyocardial biopsy is recommended to make a clear histological diagnosis aiding to differentiate from other possible conditions such as sarcoiditic myocarditis, giant cell myocarditis, and eosinophilic myocarditis. Insertion of a permanent pacemaker may be considered on a case-to-case basis.Case presentationA previously healthy 21-year-old female presented to the emergency department after having suffered two episodes of syncope on a background of a few days’ history of myalgias, chills, and rigors. Electrocardiogram showed high-grade Mobitz II block with intermittent periods of CHB. A bedside echocardiogram upon admission demonstrated normal biventricular systolic function. Given the patient’s unstable haemodynamic status and lack of obvious reversible causes for the CHB, a permanent dual-chamber pacemaker was inserted urgently. Initial blood investigations indicated an ongoing inflammatory process highlighting the possibility of myocarditis as a cause of the CHB. Therefore, a troponin level was taken and was noted to be elevated confirming the suspicion of myocarditis. The left ventricular ejection fraction (LVEF) decreased over the following days to approximately 20%, clinically resulting in pulmonary oedema and acute shortness of breath. The patient required aggressive intravenous diuresis and anti-heart failure medication. An endomyocardial biopsy (EMB) confirmed the diagnosis of lymphocytic myocarditis. The patient’s condition improved secondary to an improvement in LVEF and resolution of the heart block. A cardiac magnetic resonance (CMR) imaging performed 6 weeks from admission reported an improved LVEF of 51% with no late gadolinium enhancement (LGE). Based on the reassuring CMR findings and the resolution of CHB on follow-up pacemaker checks, it was deemed safe to explant the pacemaker.ConclusionsAcute myocarditis may be complicated with high-degree AV block and cardiogenic shock necessitating close observation in a critical care unit. A permanent pacemaker may provide atrio-ventricular synchrony which helps stabilise the patient’s condition and protect from a prolonged period of heart block. Early myocardial fibrosis on EMB and degree of LGE on CMR are indicators of persistent atrioventricular block. Guideline-directed treatment of heart failure is essential.

MYOCARDITIS IN CHILDREN PRESENTING WITH MEASLES- DATA FROM A TERTIARY CARE HOSPITAL IN PAKISTAN

Background: Measles is one of the commonest contagious diseases in children associated with numerous systemic complications.
 Objective: To find the frequency of Myocarditis in children suffering from measles.
 Methodology: This cross-sectional study was conducted in the department of pediatrics, MTI Lady Reading Hospital Peshawar from 6th December 2019 to 5th June 2020. A total of 96 patients of both genders and age range from 1-12 years having measles for more than one week were enrolled in the study after informed consent. Ethical approval for the study was obtained from Ethical Review board. Patient demographic data were collected on a structured proforma and frequency of children having clinical presentation of myocarditis was recorded. Data were entered and analyzed using SPSS 22.
 Results: The frequency of Myocarditis was 7.3% in children presented with Measles. The mean age was 6.6± 3.06 years. There were 47.9% males and 52.1% females. Most patients belonged to middle socioeconomic status i.e. 61.5%. Maternal education was 49% in 6-10 years of age group. In sampled population 46.9% belonged to urban area and 5.1% belonged to rural area. There were 18.8% vaccinated children and 81.3% were not vaccinated for measles. Myocarditis was significantly associated with younger age group (p-value 0.028), however there was no difference of gender (p-value 0.781). Children with low socioeconomic status had significantly higher frequency (p-value 0.05) of myocarditis.
 Conclusion: Myocarditis is commonly presented in children having measles especially patients in younger age group and belonging to poor socioeconomic status.

Infarct-like versus Non-Infarct-like Clinical Presentation of Acute Myocarditis: Comparison of Cardiac Magnetic Resonance (CMR) Findings.

The clinical presentation of acute myocarditis (AM) is widely variable, ranging from a subclinical disease to an infarct-like syndrome. Cardiac magnetic resonance (CMR) has become the reference non-invasive diagnostic tool for suspected AM, allowing the identification of the various hallmarks of myocardial inflammation (edema, fibrosis, and hyperemia). The aim of the study was to investigate any differences in morphological, functional, and tissue characterization CMR parameters between infarct-like AM in patients with unobstructed coronary arteries and non-infarct-like AM, diagnosed according to the original Lake-Louise Criteria (LLC); Methods: We retrospectively selected 39 patients diagnosed with AM according to LLC, divided into 2 groups according to the clinical presentation: infarct-like in group 1 patients and non-infarct-like in group 2 patients. CMR morphologic, functional, and tissue characterization parameters were analyzed and compared. In group 1, CMR tissue characterization parameters were mainly altereda in septal location with mesocardial myocardial involvement; in group 2, CMR tissue characterization parameters were mainly altered in a lateral location with subepicardial myocardial involvement mainly at the mid-cavity. No significant differences in morphological or functional parameters were observed between the two study groups. Our results showed differences in the localization and distribution of myocardial tissue damage assessed by CMR among forms of AM accompanied by an infarct-like clinical presentation compared with non-infarct-like presentations of AM. The mechanisms underlying the different preferential sites of damage observed in our study are not known, and we do not exclude the possibility of their prognostic implications.

Exploring the prognostic value of myocardial inflammation in Fabry cardiomyopathy

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

Late occurrence of ChAdOx1 vaccine-induced myocarditis presenting with ventricular arrhythmia

A 51-year-old woman who had received 2 injections of a ChAdOx1 vaccine in 2021 and a booster dose in 2022 was recently admitted for central chest pain accompanied with palpitations for the previous 2 weeks. She was negative for the COVID-19 virus, troponin was not elevated, both the 12-lead electrocardiogram and 2D echocardiogram were normal. At peak exercise during exercise treadmill test she developed a single ventricular couplet, but coronary angiography revealed normal coronary arteries. A 24-hour electrocardiogram recording revealed symptomatic non-sustained ventricular tachycardia while she was in bed. A 3T cardiac magnetic resonance imaging (MRI) demonstrated late gadolinium sub-epicardial uptake at the left ventricle apex suggesting fibrosis. The patient was diagnosed as late presentation of myocarditis following ChAdOx1 vaccination, and was discharged on oral amiodarone and colchicine.

Efficacy of catheter treatment of atrial fibrillation in patients with myocarditis depending on the adrenoreaction of the body (a prospective single-center study)

Background. Worldwide, research continues into various factors that may influence the success of catheter treatment of atrial fibrillation. In this regard, the influence of the state of the sympathoadrenal system of the body has not been studied enough. Aims to evaluate the effectiveness of interventional treatment of atrial fibrillation (AF) in patients with and without myocarditis, depending on the level of beta-adrenergic responsiveness of the organism. Materials and methods. The study sample included 40 patients. Of these, 27 (67.5%) are men. The age in the sample was 49 (44; 55) years. The study included 25 (62.5%) patients with paroxysmal AF, 10 (25.0%) with persistent and 5 (12.5%) with long-term persistent. All patients underwent surgical treatment of AF using radiofrequency (RFA) or cryoablation (CBA). Endomyocardial biopsy was performed in 18 patients to verify the diagnosis. Beta-adrenergic responsiveness (beta-ARM) was assessed in dynamics 3 days after surgery, 3 months and 12 months. The follow-up period for patients was 12 months. Results. All patients underwent surgical treatment of AF, in 7 cases (17.5%) CBA of the pulmonary veins was performed, in 33 (82.5%) cases RFA was performed. According to the biopsy results, signs of myocarditis were detected in 9 patients (22.5%). Focal myocarditis was found in 7 patients, diffuse in 2. The effectiveness of catheter treatment in general was 72.5%, for CBA 71.5%, for RFA 73.5%. Beta-ARM before ablation was 19.16% [12.46; 27.46], 3 days after ablation 24.43% [15.38; 33.65], after 3 months was 20.27% [9.90; 27.71], in 4 patients after 12 months, beta-ARM was 32.5% [20.0; 43.2]. The dynamics and influence of beta-ARM on the effectiveness of interventional treatment of AF in patients with early and late relapses, the presence of myocarditis was assessed. Conclusions. The results obtained showed no effect of the level of beta-ARM on the effectiveness of RFA and CBA in patients with and without myocarditis. Beta-ARM showed no association with the development of early arrhythmia recurrences after ablation. No statistically significant differences were found when comparing beta-ARM levels in patients with and without diagnosed myocarditis.

Presentations, Diagnosis, and Treatment of Post-COVID Viral Myocarditis in the Inpatient Setting: A Narrative Review.

While coronavirus disease 2019 (COVID-19) infection rates have declined, and mortality outcomes have improved with vaccines, targeted antiviral therapies, and improved care practices over the course of the pandemic, post-acute sequelae of SARS CoV-2 infection (PASC, also referred to as "long COVID") has emerged as a significant concern, even among individuals who appear to have fully recovered from their initial infection. Acute COVID-19 infection is associated with myocarditis and cardiomyopathies, but the prevalence and presentation of post-infectious myocarditis are unclear. We provide a narrative review of post-COVID myocarditis, including symptoms and signs, physical exam findings, diagnosis, and treatment strategies. Post-COVID myocarditis has a wide range of presentations, from very mild symptoms to severe ones that can include sudden cardiac death. Several studies have noted what appears to be a bimodal distribution of affected patients, with individuals under age 16 (particularly males) most affected, followed by those over age 50. The gold standard of diagnosis for myocarditis is endomyocardial biopsy and cardiac magnetic resonance imaging with a confirmed diagnosis of COVID-19. However, if these are not available, other studies such as electrocardiogram, echocardiography, and inflammatory markers can guide clinicians to diagnose post-COVID myocarditis when appropriate. Treatment is largely supportive and may include oxygen therapy, intravenous hydration, diuretics, steroids, and antivirals. Post-COVID myocarditis is rare but important to recognize as more patients present with this condition in the inpatient setting.

P369 AUTOIMMUNE LYMPHOCYTIC MYOCARDITIS: ONE SIZE DOES NOT FIT ALL

Abstract Fulminant myocarditis (MF) is an acute onset, rapidly progressive and potentially fatal inflammatory cardiomyopathy which could manifests with cardiogenic shock and incessant arrhythmias. There is often a need for aminic or mechanical support to the circulation in the acute phase, waiting to obtain a histological diagnosis as quickly as possible to establish a specific therapy. Mortality in the acute phases is high, with a worse prognosis than in other forms of presentation of myocarditis, even in the long term. We report the case of a 45–year–old Asian woman suffering from autoimmune hypothyroidism, who had been reporting atypical chest pain for about 3 days, associated with fever, asthenia, and vomiting. On admission, the patient was in cardiogenic shock; an echocardiogram revealed biventricular dysfunction. Pulmonary embolism and acute coronary syndrome were excluded. Blood tests showed a significant troponin rise, neutrophilic leukocytosis, and hypertransaminasemia. Anti heart antibodies (AHA) were negative. Amine support with dobutamine and norepinephrine was then started. The first EKG showed an advanced atrioventricular block with a ventricular escape with the need for emergency temporary PM placement. Right heart catheterization showed pressures in the pulmonary circulation at the upper limits with average resistance and reduced cardiac index. An endomyocardial biopsy (EMB) was performed, subsequently complicated by cardiac tamponade due to lead displacement, treated with urgent pericardiocentesis. At the end of the procedure, the appearance of incoming episodes of complete BAV was highlighted, for which ICD implantation was performed. The biopsy showed virus–negative diffuse acute lymphocytic myocarditis. Cortisone therapy was therefore started, with immediate benefit, until the aminic support was suspended. A follow–up echocardiogram showed a complete recovery of normal biventricular function. In MF, early diagnosis, and the possibility of establishing specific therapy are crucial to reduce mortality. EMB is the only method that allows you to make an etiological diagnosis and exclude a possible infectious genesis. The patient‘s prognosis, in fact, in addition to supportive therapy, depends on the possibility of establishing a targeted treatment as soon as possible, which in virus–negative autoimmune forms consists of an immunosuppressive therapy modulated on the patient‘s histological type and clinic.

PO-05-194 CARDIAC ARRHYTHMIAS AMONG MYOCARDITIS PATIENTS POSITIVE WITH COVID-19 AND ASSOCIATED MORTALITY RISK; AN ANALYSIS FROM THE 2020 NATIONAL INPATIENT SAMPLE

Viruses are the most common cause of myocarditis. With the ongoing COVID-19 pandemic, several cases of myocarditis have been reported in COVID-19 positive patients. Such patients may also experience a variety of arrhythmias that can provoke death. To evaluate the presence of various cardiac arrhythmias among COVID-19 positive myocarditis patients and understand their impact on mortality. COVID-19 positive patients, admitted between April 1st 2020 to December 31st 2020, were recruited from the 2020 National Inpatient Sample. The presence of myocarditis and various cardiac arrhythmias were also identified via their respective ICD-10 codes. Logistic regression models were used to identify the odds of mortality in the presence of myocarditis. We further proceeded to estimate the odds of mortality among myocarditis patients who had various arrhythmias. Our study found 6135 (0.4%) patients with myocarditis among 1628110 cases of COVID-19 recorded in the United States between April to December 2020. Age ranged between 0 - 90 years with a mean of 58 years. Multiple cardiac arrhythmias were also observed among myocarditis patients as 310 (5.1%) recorded supraventricular tachycardia, 520 (8.5%) had ventricular tachycardia, 120 (2.0%) had ventricular fibrillation, 520 (8.5%) had paroxysmal atrial fibrillation, 165 (2.7%) had atrial flutter, and 20 (0.3%) had long QT syndrome. The presence of myocarditis was linked with higher odds of mortality among all COVID-19 patients (aOR 2.551, 95% CI 2.405-2.706, p<0.01). Various cardiac arrhythmias were also potential predictors of mortality among myocarditis cases in COVID-19 patients, such as supraventricular tachycardia (aOR 1.346, 95% CI 1.041-1.74, p=0.023), ventricular tachycardia (aOR 1.896, 95% CI 1.557-2.308, p<0.01), ventricular fibrillation (aOR 4.161, 95% CI 2.74-6.319, p<0.01), and atrial flutter (aOR 1.485, 95% CI 1.047-2.106, p=0.026). Myocarditis was associated with higher mortality among COVID-19 admissions. Arrhythmias such as supraventricular tachycardia, ventricular tachycardia, ventricular fibrillation, and atrial flutter were predictive of higher mortality in these patients. Continued caution is advised among health-care providers encountering these arrhythmias in myocarditis patients who are COVID-19 positive.

PO-01-087 A RARE CASE OF BI-ATRIAL FDG-UPTAKE: PRESENTING AS NEW ONSET ATRIAL FIBRILLATION

Isolated atrial myocarditis is rare, with presenting symptoms that are non-specific. Prior reports have suggested association with atrial arrythmias and increased risk of stroke due to atrial dysfunction. Fluorodeoxyglucose (FDG)-positron emission tomography (PET) CT scan is considered as a goal standard test for the diagnosis of myocarditis. To present a case highlighting that isolated atrial myocarditis had higher incidence atrial arrythmias and oral anticoagulation should be considered in such cases. N/A A 55yo male with no prior medical history presented with non-specific symptoms of fatigue, shortness of breath and frequent palpitations. He underwent 2D echocardiogram showed LVEF of 50-55% with mild bi-atrial dilatation with no regional wall motion abnormalities and was diagnosed with incidental atrial fibrillation during the procedure. He was referred to cardiac electrophysiology for further work up. During his initial EP clinic visit, 12 lead ECG demonstrated normal sinus rhythm with premature atrial contractions and premature ventricular contractions. Due to symptomatic, dual chamber arrythmias, cardiac MRI (CMR) and FDG-PET CT was ordered to rule out myocarditis. The CMR was negative for any LGE however, high-fat dietary preparation FDG-PET CT scan revealed uptake on bi-atrial walls (figure) and interatrial septum with SUV max of 3.1. There was no LV myocardial FDG uptake noted. Patient was diagnosed with isolated atrial myocarditis and was started on dronedarone, OAC (CHADS2VASc =0) for stroke prophylaxis and immunosuppressive therapy (methotrexate and low dose prednisone). Invasive atrial myocardial biopsy was not considered due good response to therapy. Isolated atrial myocarditis is an uncommon presentation of acute myocarditis and is associated with atrial arrythmias. FDG PET-CT or CMR imaging may be useful to aid diagnosis. Long-term response to immunosuppressive therapy may need further investigations. OAC should be considered for stroke prophylaxis, despite low CHADS2VASc due to unknown long-term implications of atrial dysfunction.

Myocarditis in Patients With Idiopathic Inflammatory Myopathies: Clinical Presentation and Outcomes.

To determine the clinical phenotype and outcomes of patients with idiopathic inflammatory myopathies (IIMs) and myocarditis. Using the Johns Hopkins Myositis Center Research Registry, we identified 31 adult patients with IIM-out of a total of 3082 with confirmed or suspected muscle disease-with an encounter code of myocarditis from 2004 to 2021. Of these, 14 adult patients with IIM were adjudicated to have clinical myocarditis. Information about demographics, autoantibodies, and clinical outcomes was retrospectively collected and analyzed. Of 14 patients with IIM with clinical myocarditis, the median age at IIM diagnosis was 49 (IQR 35-56) years, and the median age at myocarditis diagnosis was 54 (IQR 36-61) years. The median duration between IIM diagnosis and myocarditis was 3 (IQR 2-9) years. The majority of patients were female (8/14, 57%) and Black (10/14, 71%). Antisynthetase syndrome was the most common IIM subtype (9/14, 64%). Anti-Jo1 (n = 4) and anti-PL12 (n = 3) were the most frequent autoantibodies. At myocarditis diagnosis, most patients (11/14, 79%) had active myositis, defined as elevated creatine kinase and/or muscle weakness; required hospitalization (13/14, 93%); and had reduced left ventricular ejection fraction (LVEF < 50%; 10/14, 71%). Despite intensification of immunosuppression, the 5-year overall survival rate from IIM diagnosis was 84%, and the 5-year overall survival rate from myocarditis diagnosis was 53%. Systolic dysfunction (LVEF < 40%) at final evaluation was observed in all expired patients (n = 6). Clinical presentations of myocarditis in this select cohort of patients with IIM were severe and heterogeneous with poor outcomes despite intensification of immunosuppression, potentially reflecting late detection of myocarditis.

359 - An unusual presentation of pediatric acute idiopathic myocarditis in the era of the COVID-19 pandemic

359 - An unusual presentation of pediatric acute idiopathic myocarditis in the era of the COVID-19 pandemic

Clinical Utilization of Multimodality Imaging for Myocarditis and Cardiac Sarcoidosis

Myocarditis is defined as inflammation of the myocardium according to clinical, histological, biochemical, immunohistochemical, or imaging findings. Inflammation can be categorized histologically by cell type or pattern, and many causes have been implicated, including infectious, most commonly viral, systemic autoimmune diseases, vaccine-associated processes, environmental factors, toxins, and hypersensitivity to drugs. Sarcoid myocarditis is increasingly recognized as an important cause of cardiomyopathy and has important diagnostic, prognostic, and therapeutic implications in patients with systemic sarcoidosis. The clinical presentation of myocarditis may include an asymptomatic, subacute, acute, fulminant, or chronic course and may have focal or diffuse involvement of the myocardium depending on the cause and time point of the disease. For most causes of myocarditis except sarcoidosis, myocardial biopsy is the gold standard but is limited due to risk, cost, availability, and variable sensitivity. Diagnostic criteria have been established for both myocarditis and cardiac sarcoidosis and include clinical and imaging findings particularly the use of cardiac magnetic resonance and positron emission tomography. Beyond diagnosis, imaging findings may also provide prognostic value. This case-based review focuses on the current state of multimodality imaging for the diagnosis and management of myocarditis and cardiac sarcoidosis, highlighting multimodality imaging approaches with practical clinical vignettes, with a discussion of knowledge gaps and future directions.

383: MYOCARDITIS DUE TO LEGIONELLA: A CASE REPORT

Introduction: Legionnaires’ disease is pneumonia caused due to Legionella species. Among the rare extrapulmonary manifestations, cardiac involvement is most prevalent in myocarditis, pericarditis, post-cardiotomy syndrome, and prosthetic valve endocarditis. The morbidity and mortality associated with such an uncommon presentation of legionella myocarditis are quite high. We describe a rare case of Legionella myocarditis in a 35-year-old female associated with acute left ventricular dysfunction with sepsis and pneumonitis. Description: The patient presented with fever, headache, giddiness, chills, myalgias, generalized body aches, altered mental sensorium, acute onset dyspnea, hypoxemia (83%), low blood pressure (86/56 mm Hg), respiratory failure, renal failure, and ischemic hepatic injury. She was intubated and stabilized with multiple inotropes. Echocardiography (Echo) showed borderline increase in cardiac chambers with severe, and mild mitral regurgitation (MR), mild tricuspid regurgitation (TR). The estimated LV ejection fraction (LVEF) was 10-15% with grade III LV diastolic dysfunction. X-ray showed haziness in the right lower zone with blunting of the right CP angle. She was admitted in the intensive care unit for 8 days. Due to significantly raised cardiac biomarkers (Troponin), borderline dilated chambers, and severe LV dysfunction on echocardiogram, a provisional diagnosis of fulminant myocarditis was made. Legionella infection was diagnosed on the basis of a serum pneumoslide IgM test. Although the result from the biopsy would have strengthened the diagnosis, but it was too risky. After appropriate medication, the patient improved significantly and transferred to the floor. After 10 days of monitoring, the patient was discharged and was advised follow-up after 1 week. She recovered fully and follow-up echocardiography showed marked improvement in the cardiac function. Echo Images will be presented during poster presentation. Discussion: A high degree of clinical suspicion and a thorough history is needed to suspect legionella infection. The prognosis of Legionella myocarditis depends on systemic involvement, comorbidities, and the delay before beginning directed therapy.

106 A CASE OF COMPLETE ATRIOVENTRICULAR BLOCK AND ALTERNATING BUNDLE BRANCH BLOCK DUE TO FULMINANT MYOCARDITIS

Abstract A 41-year-old man, without previous cardiological history, presented at the emergency department with hypotension and multi-organ failure. Laboratory testing showed elevated white cell blood count (16780/mcL; normal value 4000-11000/mcL; 90% neutrophils), high-sensibility troponin I (23247 ng/L; normal value &amp;lt;18 ng/L) and NT-pro-BNP (21914 pg/mL; normal value &amp;lt;300 pg/mL). At electrocardiogram (EKG) there was sinus rhythm with complete atrioventricular block and alternating right and left bundle branch block. Echocardiography revealed a moderate left ventricular (LV) dilatation, mild LV hypertrophy, severe biventricular dysfunction (LV Ejection Fraction - EF - 30%) with dense spontaneous echo contrast and moderate pulmonary hypertension (systolic pulmonary artery pressure 51 mmHg). After positioning a temporary pacemaker, the patient was transferred to our Cardiac Intensive Care Unit. After initial hemodynamic stabilization with endovenous inotropes, diuretics, and mechanical circulatory support (intra-aortic balloon pump), coronary angiography was performed showing normal coronary arteries. Since fulminant myocarditis was suspected and magnetic resonance was not feasible due to the patient's instability, an endomyocardial biopsy (EMB) was performed with the evidence of myocardial edema, initial myocardial fibrosis, and the concomitant presence of lymphocytic and eosinophilic endo-myocarditis (despite normal eosinophilic blood count) without evidence of active viral replication. After careful exclusion of latent or active infections, high doses of corticosteroids and azathioprine were initiated, with rapid laboratoristic and clinical response. EKG showed AV block regression and QRS width's normalization, so the pacemaker was removed. LVEF rapidly improved and was completely normalized at discharge after two weeks. In the early follow-up, a cardiac magnetic resonance (CMR) was performed with evidence of persistency of mildly dilated LV, normalization of LV wall thickness and biventricular function, a diffuse increase of T1 relaxation time, increased T2 signal of the anterior and septal walls, and intramural anteroseptal late gadolinium enhancement (LGE). Fulminant myocarditis is a rare presentation of acute myocarditis, with low incidence but high mortality. The inflammation of the myocardium itself leads to acute heart failure, cardiogenic shock, and cardiac arrhythmias, including sinus arrest, AV block, ventricular tachycardia, and ventricular fibrillation during the acute phase. In our case, AV block could be an expression of anteroseptal involvement, documented at CMR. This localization has already been associated with worse clinical presentation and could be a marker of poor prognosis. Diagnosis and treatment of fulminant myocarditis require EMB, to obtain information about the etiology and active viral replication in the heart tissue. In our case, the florid inflammatory state and the absence of viral replication allowed prompt treatment with immunosuppressors, with a quick and full recovery of biventricular function in only two weeks.

163: THINK INSIDE THE BOX: ACUTE MITRAL REGURGITATION MASQUERADING AS PEDIATRIC ARDS

Introduction: Acute mitral regurgitation (MR) due to papillary muscle rupture is a recognized complication of adult myocardial infarction but is rare in pediatrics. Presenting with dyspnea, acute pulmonary edema, and shock, acute MR can mimic acute respiratory distress syndrome (ARDS). Accurate and timely diagnosis is critical, as acute MR is a surgical emergency with high mortality risk. Description: A previously healthy 12-year-old male presented to the emergency department with one day of emesis, palpitations, and dyspnea. He was tachypneic, tachycardic, and hypoxemic and received supplemental oxygen and a 20 ml/kg fluid bolus. Chest radiograph showed bilateral infiltrates, point-of-care ultrasound (POCUS) was concerning for pneumonia, and antibiotics were given. POCUS also showed hyperdynamic left and normal right ventricular systolic function without pericardial effusion. He developed rapidly progressive hypoxic respiratory failure and was intubated. Intubation was notable for copious pink, frothy secretions. After PICU admission, he had progressive hemodynamic instability and rising lactate requiring escalation of vasopressors and inotropes. A complete echocardiogram showed mild MR and normal function. Due to rising mean airway pressure and worsening oxygenation index, he was cannulated to veno-venous extracorporeal membrane oxygenation. Repeat echocardiogram post-cannulation showed moderate to severe MR, prolapse of the anterior mitral leaflet, a prominent round papillary muscle, moderate left atrial dilation, mild-moderate left ventricular dilation, and hyperdynamic LV systolic function. Trans-esophageal echocardiogram confirmed diagnosis of acute MR due to papillary muscle rupture. He underwent mitral valve replacement with a St. Jude prosthetic mechanical valve. Pathologic evaluation of excised tissue showed lymphocytic myocarditis, endocardial inflammation, and patchy fibrosis. Rheumatologic evaluation is ongoing, and patient was discharged in good condition. Discussion: We report a rare presentation of lymphocytic myocarditis with papillary muscle rupture and acute MR. The presentation mimicked a rapid progression of pediatric ARDS, and highlights that a high index of suspicion is required to ensure timely diagnosis of this life-threatening process.

Acute myocarditis masquerading as anterior wall myocardial infarction: A case report

Myocarditis is the inflammation of the myocardium. The clinical presentation of myocarditis ranges from asymptomatic state to acute heart failure which may mimic acute coronary events. Because of the similar presentation of chest pain, elevated cardiac enzymes, and electrocardiographic (ECG) changes, acute myocarditis may rarely masquerade as acute myocardial infarction (AMI). High suspicion is often necessary for treating such patients, keeping in mind the different treatment protocols required for managing each pathology. SCARE 2020 Guidelines. We report a case of a young female presenting with sudden onset chest pain with ECG changes suggestive of acute anterior wall myocardial infarction (AWMI). Further investigations ruled out AWMI, and she was diagnosed with acute myocarditis. She was treated for myocarditis and showed a prompt recovery. Acute myocarditis may present clinically similarly to ACS; hence a high level of suspicion is required to differentiate the two entities. The absence of significant cardiovascular risk factors for atherosclerotic coronary artery disease, absence of RWMA, and normal coronary angiogram are further suggestive of myocarditis.

Clinical Presentation of Myocarditis in Children Visiting Dr Ruth KM PFAU, Civil Hospital, Karachi. A Cross-Sectional Study

Objective: To determine the frequency of various clinical presentations of myocarditis in children visiting to Dr Ruth KM PFAU, Civil Hospital Karachi. Study design: Cross-Sectional Study. Place and duration: Department of Pediatric Medicine, Dr Ruth K.M PFAU Civil Hospital, Karachi, Pakistan from September, 2020, to March, 2021 Methodology: The study covered all patients who visited Karachi's Civil Hospital and met the inclusion criteria. After describing the study's process, hazards, and benefits, informed consent was obtained. The initial ECG, echocardiography, and cardiac enzyme readings were all documented. Stroke, congenital heart disease, sepsis, asthma, pulmonary embolism, cardiomyopathy, gastroenteritis, diabetes mellitus, and renal failure were among the clinical presentations that were noted. The proforma that is supplied at the end was filled out with all the acquired data and used electronically for research. Results: Age was 6.8± 2.1 years on average. A total of 238 (67.6%) of the 352 patients were male, and 114 (32.4%) were female. In patients with myocarditis who presented clinically, renal disease was found in 46 (13.1%), cardiomyopathy in 30, congenital heart disease in 56 (15.9%), stroke in 41 (11.5%), gastroenteritis in 65 (18.5%), diabetes mellitus in 19 (5.4%), sepsis in 32 (9.2%), and asthma in 48 (13.6%) patients, while pulmonary embolism was found in 15 (4.3%) patients. Practical implication There is growing evidence to support the use of tests such as cardiac magnetic resonance imaging and serum N-terminal B-type natriuretic peptide measurements as supplements to clinical diagnosis. These could eventually lessen the need for invasive procedures like endomyocardial biopsy, which is still the gold standard. Conclusion: The most frequent clinical manifestation of myocarditis was gastroenteritis, which was followed by congenital heart disease and asthma. For the purpose of validating the results so far, additional extensive research is advised. Keywords: Clinical Presentation, Myocarditis, Epidemiology, Asthma, Gastroenteritis

Clinical Presentation of Myocarditis in the Pediatric Age Group and Predictors of Poor Early and Late Outcomes: Academic Hospital Experience.

Myocarditis is a leading cause of morbidity and mortality in the pediatric age group and contributes to a wide range of complications, including dilated cardiomyopathy, congestive heart failure, and even death, so early identification and comprehensive management are essential for a favorable outcome. Summarize the presenting clinical signs and symptoms of pediatric patients with a diagnosis of myocarditis and a poor outcome and correlate the clinical presentation and laboratory and radiographic findings to identify possible predictors of a poor outcome. This retrospective cohort study included all patients who were diagnosed with myocarditis and followed up at King Abdulaziz University Hospital, Jeddah, Saudi Arabia over the 13 years between January 01, 2007, and December 31, 2019. Information on patient demographics, clinical presentation, and non-invasive investigations was obtained. Poor outcomes were defined as death or evidence of left ventricular dysfunction on echocardiography which was evaluated at two points in time as an early outcome and a late outcome. Seventeen patients (male 52.9%, female 47.1%) with a median age of 4 ± 4.31 years are included. The most frequent initial complaints were exercise or feeding intolerance, respiratory symptoms, and shortness of breath. On the other hand, hepatomegaly and respiratory distress were the most common clinical signs. All the patients were admitted to the pediatric intensive care unit but only 41% required mechanical ventilation. The presence of a murmur at presentation was significantly correlated with a poor early outcome. Ischemic changes on the electrocardiogram and moderate left ventricular dysfunction on the echocardiogram were significantly correlated with a poor late outcome. Diagnosis of myocarditis can be established by a combination of clinical presentation and investigative tools. A murmur, ischemic changes on the electrocardiogram, and left ventricular dysfunction are important predictors of myocarditis in children.