Post-acute Myocarditis Persistent Inflammation Score (MRI + Biomarkers) Calculator

Post-acute Myocarditis Persistent Inflammation Score (MRI + Biomarkers): Explanation and Clinical Context This calculator provides a pragmatic, literature-informed composite score to estimate the likelihood of persistent myocardial inflammation after an acute myocarditis episode using follow-up cardiovascular magnetic resonance (CMR) features and blood biomarkers. It weights factors consistently linked with adverse outcomes or ongoing inflammation at follow-up: persistence or progression of late gadolinium enhancement (LGE), septal LGE, larger LGE burden, edema (T2), diffuse injury (native T1/ECV), left ventricular systolic dysfunction (LVEF) and impaired deformation (GLS), together with persistent myocardial injury (hs-troponin), neurohormonal stress (NT-proBNP), and systemic inflammation (CRP). Cut-points and weights are aligned with signals reported across contemporary studies and consensus documents; notably, follow-up CMR around 3 months is commonly recommended to detect residual disease activity and high-risk LGE patterns or extent.

How to interpret: Low risk (0–2) suggests a low likelihood of ongoing active inflammation; routine clinical follow-up is generally appropriate. Intermediate risk (3–4) indicates possible persistent inflammation; consider closer monitoring and repeat CMR if symptoms, biomarkers, or ECG change. High risk (≥5) reflects a higher probability of persistent inflammation and of adverse events; consider intensifying follow-up, risk-factor control, and therapy in line with expert consensus, and individualize decisions with a cardiomyopathy/myocarditis team.

This score is not a substitute for clinical judgment, endomyocardial biopsy when indicated, or guideline-directed management. It is intended to standardize phenotyping at follow-up and to complement existing guidance. Notes on evidence and derivation: • Persistence/progression of LGE at ~6-month CMR, septal LGE, reduced LVEF at admission/follow-up, impaired GLS, and prolonged troponin elevation were all associated with adverse events in a prospective cohort proposing a multiparametric prognostic score (Di Lisi et al., 2024). • Reviews and consensus statements emphasize that CMR integrates edema (T2), necrosis/fibrosis (LGE), and diffuse injury (native T1/ECV) and should be repeated at ≈3 months to detect residual inflammation and high-risk LGE extent/patterns; enzymes alone may normalize despite ongoing LGE. • Biomarker dynamics (hs-cTn, NT-proBNP) and systemic inflammatory markers (e.g., CRP) can add prognostic information but do not replace imaging; persistent abnormality beyond the acute phase supports ongoing disease activity. • Because no single universally validated “post-acute persistent inflammation” score is yet established, this calculator operationalizes published risk signals into a transparent point system to aid consistent reporting and shared decision-making.

Where available, users should also consult original risk models and apply lab-specific reference limits.