Myocarditis and the Role of Cardiac Imaging

Myocarditis, an inflammatory condition of the myocardium, can present with a spectrum of clinical manifestations, ranging from mild symptoms to cardiogenic shock or death. While endomyocardial biopsy (EMB) remains the gold standard for diagnosis, its invasive nature and limited sensitivity have shifted focus toward non-invasive imaging, particularly cardiovascular magnetic resonance (CMR) imaging. CMR has emerged as a cornerstone in diagnosing myocarditis, offering high sensitivity and specificity through advanced tissue characterisation and functional assessment. Key CMR techniques include T1 and T2 mapping, which allow quantitative evaluation of myocardial injury, oedema, and fibrosis, alongside late gadolinium enhancement (LGE), which identifies predominantly necrosis and scar tissue. The revised 2018 Lake Louise Criteria have further standardised the diagnostic approach with integration of mapping for enhanced accuracy. However, emerging technologies, such as radiomics with machine learning techniques, show promise in improving diagnostic precision, risk stratification, and prognostication. This review explores the pathophysiology, clinical manifestations, and underlying causes of myocarditis, with a particular emphasis on the role of imaging modalities. It highlights the central importance of CMR in the diagnosis and management of myocarditis, while also underscoring the need for ongoing innovation and advancements to enhance patient outcomes.