Appearance of COVID-19 pneumonia on 1.5 T TrueFISP MRI.

OBJECTIVE: To evaluate the performance of 1.5 T true fast imaging with steady state precession (TrueFISP) magnetic resonance imaging (MRI) sequences for the detection and characterization of pulmonary abnormalities caused by coronavirus disease 2019 (COVID-19). MATERIALS AND METHODS: In this retrospective single-center study, computed tomography (CT) and MRI scans of 20 patients with COVID-19 pneumonia were evaluated with regard to the distribution, opacity, and appearance of pulmonary lesions, as well as bronchial changes, pleural effusion, and thoracic lymphadenopathy. McNemar's test was used in order to compare the COVID-19-associated alterations seen on CT with those seen on MRI. RESULTS: Ground-glass opacities were better visualized on CT than on MRI (p = 0.031). We found no statistically significant differences between CT and MRI regarding the visualization/characterization of the following: consolidations; interlobular/intralobular septal thickening; the distribution or appearance of pulmonary abnormalities; bronchial pathologies; pleural effusion; and thoracic lymphadenopathy. CONCLUSION: Pulmonary abnormalities caused by COVID-19 pneumonia can be detected on TrueFISP MRI sequences and correspond to the patterns known from CT. Especially during the current pandemic, the portions of the lungs imaged on cardiac or abdominal MRI should be carefully evaluated to promote the identification and isolation of unexpected cases of COVID-19, thereby curbing further spread of the disease.

OBJETIVO: Avaliar o desempenho da ressonância magnética (RM) de 1,5 T true fast imaging with steady state precession (TrueFISP) para detecção e caracterização de anormalidades pulmonares causadas por doença do coronavírus 2019 (COVID-19). MATERIAIS E MÉTODOS: Neste estudo retrospectivo unicêntrico, imagens de tomografia computadorizada (TC) e RM de 20 pacientes com pneumonia COVID-19 foram avaliadas em relação a distribuição, opacidade e forma das lesões pulmonares, anormalidades brônquicas, derrame pleural e linfadenopatia torácica. O teste de McNemar foi usado para comparar os achados associados à COVID-19 na TC e na RM. RESULTADOS: As opacidades em vidro fosco foram mais bem visualizadas na TC do que na RM (p = 0,031). Não foram encontradas diferenças estatisticamente significantes entre TC e RM em relação aos outros aspectos, ou seja, visualização de consolidações e espessamento septal interlobular/intralobular, distribuição ou forma de anormalidades pulmonares, doenças brônquicas, derrame pleural ou linfadenopatia torácica. CONCLUSÃO: As anomalias pulmonares causadas pela pneumonia por COVID-19 podem ser detectadas nas sequências TrueFISP e correspondem aos padrões conhecidos da TC. Especialmente em face da pandemia atual, as porções de imagem dos pulmões na RM cardíaca ou abdominal devem ser cuidadosamente avaliadas para apoiar a identificação e o isolamento de casos inesperados de COVID-19 e, assim, conter a disseminação.

Differences in Cardiac Magnetic Resonance Imaging Markers Between Patients With COVID-19-associated Myocardial Injury and Patients With Clinically Suspected Myocarditis.

PURPOSE: Coronavirus 2019 disease (COVID-19) has been shown to affect the myocardium, resulting in a worse clinical outcome. In this registry study, we aimed to identify differences in cardiac magnetic resonance imaging (CMRI) between COVID-19 and all-cause myocarditis. MATERIALS AND METHODS: We examined CMRI of patients with COVID-19 and elevated high-sensitivity serum troponin levels performed between March 31st and May 5th and compared them to CMRI of patients without SARS-CoV-2 infection with suspected myocarditis in the same time period. For this purpose, we evaluated Lake-Louise Criteria for myocarditis by determining nonischemic myocardial injury via T1-mapping, extracellular volume, late gadolinium enhancement, and myocardial edema (ME) by T2-mapping and fat-saturated T2w imaging (T2Q). RESULTS: A total of 15 of 18 (89%) patients with COVID-19 had abnormal findings. The control group consisted of 18 individuals. There were significantly fewer individuals with COVID-19 who had increased T2 (5 vs. 10; P=0.038) and all-cause ME (7 vs. 15; P=0.015); thus, significantly fewer patients with COVID-19 fulfilled Lake-Louise Criteria (6 vs. 17; P<0.001). In contrast, nonischemic myocardial injury was not significantly different. In the COVID-19 group, indexed end-diastolic volume of the left ventricle showed a significant correlation to the extent of abnormal T1 (R2=0.571; P=0.017) and extracellular volume (R2=0.605; P=0.013) and absolute T1, T2, and T2Q (R2=0.644; P=0.005, R2=0.513; P=0.035 and R2=0.629; P=0.038, respectively); in the control group, only extracellular volume showed a weak correlation (R2=0.490; P=0.046). CONCLUSIONS: Cardiac involvement in COVID-19 seems to show less ME than all-cause myocarditis. Abnormal CMRI markers correlated to left ventricle dilation only in the COVID-19 group. Larger comparative studies are needed to verify our findings.

Myocardial Inflammation and Dysfunction in COVID-19-Associated Myocardial Injury.

BACKGROUND: Myocardial injury, defined by elevated troponin levels, is associated with adverse outcome in patients with coronavirus disease 2019 (COVID-19). The frequency of cardiac injury remains highly uncertain and confounded in current publications; myocarditis is one of several mechanisms that have been proposed. METHODS: We prospectively assessed patients with myocardial injury hospitalized for COVID-19 using transthoracic echocardiography, cardiac magnetic resonance imaging, and endomyocardial biopsy. RESULTS: Eighteen patients with COVID-19 and myocardial injury were included in this study. Echocardiography revealed normal to mildly reduced left ventricular ejection fraction of 52.5% (46.5%-60.5%) but moderately to severely reduced left ventricular global longitudinal strain of -11.2% (-7.6% to -15.1%). Cardiac magnetic resonance showed any myocardial tissue injury defined by elevated T1, extracellular volume, or late gadolinium enhancement with a nonischemic pattern in 16 patients (83.3%). Seven patients (38.9%) demonstrated myocardial edema in addition to tissue injury fulfilling the Lake-Louise criteria for myocarditis. Combining cardiac magnetic resonance with speckle tracking echocardiography demonstrated functional or morphological cardiac changes in 100% of investigated patients. Endomyocardial biopsy was conducted in 5 patients and revealed enhanced macrophage numbers in all 5 patients in addition to lymphocytic myocarditis in 1 patient. SARS-CoV-2 RNA was not detected in any biopsy by quantitative real-time polymerase chain reaction. Finally, follow-up measurements of left ventricular global longitudinal strain revealed significant improvement after a median of 52.0 days (-11.2% [-9.2% to -14.7%] versus -15.6% [-12.5% to -19.6%] at follow-up; P=0.041). CONCLUSIONS: In this small cohort of COVID-19 patients with elevated troponin levels, myocardial injury was evidenced by reduced echocardiographic left ventricular strain, myocarditis patterns on cardiac magnetic resonance, and enhanced macrophage numbers but not predominantly lymphocytic myocarditis in endomyocardial biopsies.