BACKGROUND The Long-terM OUtcomes after the Multisystem Inflammatory Syndrome In Children (MUSIC) study aims to characterize the frequency and time course of acute and long-term cardiac and non-cardiac sequelae in multisystem inflammatory syndrome in children associated with COVID-19 (MIS-C), which are currently poorly understood. METHODS This multicenter observational cohort study will enroll at least 600 patients <21 years old who meet the Centers for Disease Control and Prevention case definition of MIS-C across multiple North American centers over 2 years. The study will collect detailed hospital and follow-up data for up to 5 years, and optional genetic testing. Cardiac imaging at specific time points includes standardized echocardiographic assessment (all participants) and cardiac magnetic resonance imaging (CMR) in those with left ventricular ejection fraction (LVEF) <45% during the acute illness. The primary outcomes are the worst LVEF and the highest coronary artery z-score of the left anterior descending or right coronary artery. Other outcomes include occurrence and course of non-cardiac organ dysfunction, inflammation, and major medical events. Independent adjudication of cases will classify participants as definite, possible, or not MIS-C. Analysis of the outcomes will include descriptive statistics and regression analysis with stratification by definite or possible MIS-C. The MUSIC study will provide phenotypic data to support basic and translational research studies. CONCLUSION The MUSIC study, with the largest cohort of MIS-C patients and the longest follow-up period to date, will make an important contribution to our understanding of the acute cardiac and non-cardiac manifestations of MIS-C and the long-term effects of this public health emergency.

中文翻译：

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NHLBI 儿童多系统炎症综合征 (MUSIC) 后长期结果的研究：设计和目标。

背景 儿童多系统炎症综合征 (MUSIC) 研究后的长期结果旨在描述与 COVID-19 (MIS) 相关的儿童多系统炎症综合征的急性和长期心脏和非心脏后遗症的频率和时间进程-C)，目前还知之甚少。方法 这项多中心观察性队列研究将招募至少 600 名 <21 岁且符合美国疾病控制和预防中心 MIS-C 病例定义的患者，时间跨度超过 2 年，跨越多个北美中心。该研究将收集长达 5 年的详细医院和随访数据，以及可选的基因检测。特定时间点的心脏成像包括标准化超声心动图评估（所有参与者）和急性疾病期间左心室射血分数 (LVEF) <45% 的患者的心脏磁共振成像 (CMR)。主要结果是最差的 LVEF 和左冠状动脉前降支或右冠状动脉的最高冠状动脉 z 评分。其他结局包括非心脏器官功能障碍、炎症和重大医疗事件的发生和病程。案件的独立裁决会将参与者分类为确定的、可能的或不是 MIS-C。结果分析将包括描述性统计和回归分析，并通过明确或可能的 MIS-C 进行分层。MUSIC 研究将提供表型数据以支持基础和转化研究。