Myocarditis presenting as typical acute myocardial infarction: A case report and review of the literature

Recent Advances in Cardiac Magnetic Resonance for Imaging of Acute Myocardial Infarction

Acute myocardial infarction (AMI) is one of the primary causes of death worldwide, with a high incidence and mortality rate. Assessment of the infarcted and surviving myocardium, along with microvascular obstruction, is crucial for risk stratification, treatment, and prognosis in patients with AMI. Nonionizing radiation, excellent soft tissue contrast resolution, a large field of view, and multiplane imaging make cardiac magnetic resonance (CMR) a "one-stop" method for assessing cardiac structure, function, perfusion, and metabolism. Hence, this imaging technology is considered the "gold standard" for evaluating myocardial function and viability in AMI. This review critically compares the advantages and disadvantages of CMR with other cardiac imaging technologies, and relates the imaging findings to the underlying pathophysiological processes in AMI. A more thorough understanding of CMR technology will clarify their advanced clinical diagnosis and prognostic assessment applications, and assess the future approaches and challenges of CMR in the setting of AMI.

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

Introduction

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.

Methods

SCARE 2020 Guidelines.

Case report

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.

Discussion

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.

Effects of Tranilast on Inflammasome and Macrophage Phenotype in a Mouse Model of Myocardial Infarction

Acute myocardial infarction (AMI) has been a devastating actuality and accounts for half of cardiovascular emergency department visits. Nucleotide oligomerization domain, leucine-rich repeat, and pyrin domain-containing protein 3 (NLRP3) inflammasome participates in the mediation of myocardial inflammation during AMI. Therefore, this study aimed to reveal the therapeutic function of tranilast, an agent targeting NLRP3, for AMI. AMI mouse model was first established by transient myocardial ischemia. Western blot and quantitative reverse transcription polymerase chain reaction assay were performed to estimate the expression levels of related genes. Flow cytometry was used to analyze the macrophage types, and the therapeutic effects of tranilast were estimated by echocardiographic analysis and Masson's trichrome stain. We demonstrated that AMI induced the activation of NLRP3 inflammasome in the heart tissues of mice with AMI. Tranilast decreased the expression of interleukin-1β and cleaved caspase-1 in bone marrow-derived macrophages and thus re-educated M1-macrophages toward the M2-phenotype both in vitro and in vivo. Tranilast inhibited the activation in the heart tissues of AMI mice and thus improved cardiac functional recovery in the AMI mouse model. In conclusion, we revealed that tranilast ameliorated myocardial infarction by inhibiting NLRP3 inflammasome and re-educating macrophage phenotype in this study.