Importance Although myocardial injury can occur with acute COVID-19, there is limited understanding of changes with myocardial metabolism in recovered patients.

Objective To examine myocardial metabolic changes early after recovery from COVID-19 using fluorodeoxyglucose–positron emission tomography (PET) and associate these changes to abnormalities in cardiac magnetic resonance imaging (MRI)–based function and tissue characterization measures and inflammatory blood markers.

Design, Setting, and Participants This prospective cohort study took place at a single-center tertiary referral hospital system. A volunteer sample of adult patients within 3 months of a diagnosis of COVID-19 who responded to a mail invitation were recruited for cardiac PET/MRI and blood biomarker evaluation between November 2020 and June 2021.

Exposures Myocardial inflammation as determined by focal fluorodeoxyglucose (FDG) uptake on PET.

Main Outcomes and Measures Demographic characteristics, cardiac and inflammatory blood markers, and fasting combined cardiac ¹⁸F-FDG PET/MRI imaging were obtained. All patients with focal FDG uptake at baseline returned for repeated PET/MRI and blood marker assessment 2 months later.

Results Of 47 included patients, 24 (51%) were female, and the mean (SD) age was 43 (13) years. The mean (SD) interval between COVID-19 diagnosis and PET/MRI was 67 (16) days. Most patients recovered at home during the acute infection (40 [85%]). Eight patients (17%) had focal FDG uptake on PET consistent with myocardial inflammation. Compared with those without FDG uptake, patients with focal FDG uptake had higher regional T2, T1, and extracellular volume (colocalizing with focal FDG uptake), higher prevalence of late gadolinium enhancement (6 of 8 [75%] vs 9 of 39 [23%], P = .009), lower left ventricular ejection fraction (mean [SD], 55% [4%] vs 62% [5%], P < .001), worse global longitudinal and circumferential strain (mean [SD], −16% [2%] vs −17% [2%], P = .02 and −18% [2%] vs −20% [2%], P = .047, respectively), and higher systemic inflammatory blood markers including interleukin 6, interleukin 8, and high-sensitivity C-reactive protein. Among patients with focal FDG uptake, PET/MRI, and inflammatory blood markers resolved or improved at follow-up performed a mean (SD) of 52 (17) days after baseline PET/MRI.

Conclusions and Relevance In this study of patients recently recovered from COVID-19, myocardial inflammation was identified on PET in a small proportion of patients, was associated with cardiac MRI abnormalities and elevated inflammatory blood markers at baseline, and improved at follow-up.

重要性 尽管急性 COVID-19 可能会导致心肌损伤，但对康复患者心肌代谢变化的了解有限。

目的 使用氟脱氧葡萄糖-正电子发射断层扫描 (PET) 检查 COVID-19 恢复后的早期心肌代谢变化，并将这些变化与基于心脏磁共振成像 (MRI) 的功能和组织特征测量以及炎症性血液标志物的异常联系起来。

设计、设置和参与者 这项前瞻性队列研究在一个单中心三级转诊医院系统中进行。在 2020 年 11 月至 2021 年 6 月期间，招募了在确诊 COVID-19 后 3 个月内回复邮件邀请的成年患者志愿者样本进行心脏 PET/MRI 和血液生物标志物评估。

通过 PET 上的局灶性氟脱氧葡萄糖 (FDG) 摄取来确定心肌炎症。

获得主要成果和措施 人口统计学特征、心脏和炎症血液标志物以及空腹联合心脏¹⁸ F-FDG PET/MRI 成像。2 个月后，所有基线时局灶性 FDG 摄取的患者都返回进行重复 PET/MRI 和血液标志物评估。

结果 47 名纳入患者中，24 名 (51%) 为女性，平均 (SD) 年龄为 43 (13) 岁。COVID-19 诊断和 PET/MRI 之间的平均 (SD) 间隔为 67 (16) 天。大多数患者在急性感染期间在家中康复 (40 [85%])。8 名患者 (17%) 在 PET 上发现局灶性 FDG 摄取与心肌炎症一致。与没有 FDG 摄取的患者相比，有局灶性 FDG 摄取的患者具有更高的局部 T2、T1 和细胞外体积（与局灶性 FDG 摄取共定位），晚期钆增强的患病率更高（8 例中有 6 例 [75%] vs 39 例中有 9 例 [23] %]，P  = .009），左心室射血分数较低（平均 [SD]，55% [4%] vs 62% [5%]，P  < .001），整体纵向和圆周应变较差（平均 [SD ], -16% [2%] 对比 -17% [2%], P = .02 和 −18% [2%] 对比 −20% [2%]，P  = .047，分别），以及更高的全身炎症性血液标志物，包括白细胞介素 6、白细胞介素 8 和高敏 C 反应蛋白。在具有局灶性 FDG 摄取、PET/MRI 和炎症性血液标记物的患者中，在基线 PET/MRI 后平均 (SD) 为 52 (17) 天。

结论和相关性 在这项针对最近从 COVID-19 康复的患者中进行的研究中，一小部分患者在 PET 上发现了心肌炎症，与心脏 MRI 异常和基线时炎症性血液标志物升高有关，并在随访中有所改善。