Systematic Review and Meta-Analysis of Myocarditis Prevalence and Diagnostics in COVID-19:Acute, Post-COVID, and MIS-C (2020–2025)

Figures

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  Figure 1. PRISMA 2020 flow diagram detailing study selection, showing 18,256 records identified, 12,844 records screened, 1332 records full-text reviewed, and 73 records included (23 records for quantitative synthesis, n = 36,673), according to PRISMA 2020 guidelines [Page et al., 2021 [27]. The 23 studies included in the quantitative synthesis are: Esposito [11], Puntmann [12], Huang [13], Rajpal [16], Starekova [17], Vago [18], Moulson [19], Petek [20], Ammirati [21], Kim [22], Martinez [28], Daniels [29], Vidula [30], Doeblin [31], Artico [32], Gröschel [24], Tugade [25], Blondiaux [26], Benvenuto [33], Karas [34], Scarduelli [35], Arslan [36], and Patel [37].

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  Figure 2. Forest plot of myocarditis prevalence across 23 studies (n = 36,673), showing a pooled estimate of 1.8% (95% CI: 1.2–2.6%) with high heterogeneity (I2 = 98%). References are cited by number as follows: Esposito [11], Puntmann [12], Huang [13], Rajpal [16], Starekova [17], Vago [18], Moulson [19], Petek [20], Ammirati [21], Kim [22], Gröschel [24], Tugade [25], Blondiaux [26], Benvenuto [33], Karas [34], Scarduelli [35], Patel [37], Vidula [30], Daniels [29], Martinez [28], Doeblin [31], Artico [32], Arslan [36].

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  Figure 3. Subgroup analyses of myocarditis prevalence: (A) by diagnostic method (CMR: 11.2%, biopsy: 2.8%, clinical: 0.3%); (B) by disease phase (MIS-C: 32.1%, post-COVID: 4.9%, acute: 0.31%); (C) by clinical setting (ICU: 3.1%, non-ICU: 0.9%), presented as a composite figure.

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  Figure 4. Funnel plot assessing publication bias across 23 studies, showing minimal asymmetry (Egger’s p = 0.16) and trim-and-fill adjusted prevalence of 1.5% (95% CI: 0.9–2.3%).