Purpose of Review

In coronavirus disease 2019 (COVID-19), myocardial injury occurs frequently in severe or critically ill hospitalized patients, yet myocarditis is much less common. In this context, revisiting the definition of myocarditis is appropriate with a specific focus on diagnostic and management considerations in patients infected with SARS-CoV-2.

Recent Findings

Pathologic cardiac specimens from patients with COVID-19 suggest a mixed inflammatory response involving lymphocytes and macrophages, and importantly, cellular injury occurs predominantly at the level of pericytes and endothelial cells, less often involving direct myocyte necrosis. In COVID-19, the diagnosis of myocarditis has understandably been based predominantly on clinical criteria, and the number of patients with clinically suspected myocarditis who would meet diagnostic histological criteria is unclear. Echocardiography and cardiac magnetic resonance are important diagnostic tools, although the prognostic implications of abnormalities are still being defined. Importantly, SARS-CoV2 myocarditis should be diagnosed within an appropriate clinical context and should not be based on isolated imaging findings. Therapies in COVID-19 have focused on the major clinical manifestation of pneumonia, but the promotion of viral clearance early in the disease could prevent the development of myocarditis, and further study of immunosuppressive therapies once myocarditis has developed are indicated.

Summary

A strict and uniform approach is needed to diagnose myocarditis due to SARS-CoV-2 to better understand the natural history of this disease and to facilitate evaluation of potential therapeutic interventions. A methodological approach will also better inform the incidence of COVID-19 associated myocarditis and potential long-term health effects.

中文翻译：

---

SARS-CoV-2 心肌炎：深入了解发病率、预后和治疗意义

 审查目的

在2019冠状病毒病（COVID-19）中，重症或危重症住院患者经常发生心肌损伤，但心肌炎则少见。在这种情况下，重新审视心肌炎的定义是适当的，特别关注感染 SARS-CoV-2 的患者的诊断和管理注意事项。

 最近的发现

COVID-19患者的病理心脏标本表明涉及淋巴细胞和巨噬细胞的混合炎症反应，重要的是，细胞损伤主要发生在周细胞和内皮细胞水平，很少涉及直接心肌细胞坏死。在 COVID-19 中，心肌炎的诊断主要基于临床标准，这是可以理解的，而临床疑似心肌炎的患者符合诊断组织学标准的人数尚不清楚。超声心动图和心脏磁共振是重要的诊断工具，尽管异常的预后影响仍在确定中。重要的是，SARS-CoV2 心肌炎应在适当的临床背景下进行诊断，而不应基于孤立的影像学检查结果。 COVID-19的治疗主要集中在肺炎的主要临床表现上，但在疾病早期促进病毒清除可以预防心肌炎的发展，并且一旦出现心肌炎就需要进一步研究免疫抑制治疗。

 概括

需要采用严格且统一的方法来诊断 SARS-CoV-2 引起的心肌炎，以更好地了解这种疾病的自然史并促进评估潜在的治疗干预措施。方法学方法还将更好地了解与 COVID-19 相关的心肌炎的发病率和潜在的长期健康影响。