This copy is for personal use only. To order printed copies, contact reprints@rsna.org I n P r e s s 2 Key Points 1. The positive rates of RT-PCR assay and chest CT imaging in our cohort were 59% (601/1014), and 88% (888/1014) for the diagnosis of suspected patients with COVID-19, respectively. 2.With RT-PCR as a reference, the sensitivity of chest CT imaging for COVID-19 was 97% (580/601). In patients with negative RT-PCR results but positive chest CT scans (n=308 patients), 48% (147/308) of patients were re-considered as highly likely cases, with 33% (103/308) as probable cases by a comprehensive evaluation. 3.With analysis of serial RT-PCR assays and CT scans, 60% to 93% of patients had initial positive chest CT consistent with COVID-19 before the initial positive RT-PCR results. 42% of patients showed improvement of follow-up chest CT scans before the RT-PCR results turning negative. Summary StatementChest CT had higher sensitivity for diagnosis of COVID-19 as compared with initial reverse-transcription polymerase chain reaction (RT-PCR) from swab samples in the epidemic area of China. Abbreviations RT-PCR = reverse transcription polymerase chain reaction NCP = novel coronavirus pneumonia PPV = positive predictive value NPV = negative predictive value I n P r e s s 3 Abstract Background: Chest CT is used for diagnosis of 2019 novel coronavirus disease (COVID-19), as an important complement to the reverse-transcription polymerase chain reaction (RT-PCR) tests. Purpose: To investigate the diagnostic value and consistency of chest CT as compared with comparison to RT-PCR assay in COVID-19. underwent both chest CT and RT-PCR tests were included. With RT-PCR as reference standard, the performance of chest CT in diagnosing COVID-19 was assessed. Besides, for patients with multiple RT-PCR assays, the dynamic conversion of RT-PCR results (negative to positive, positive to negative, respectively) was analyzed as compared with serial chest CT scans for those with time-interval of 4 days or more. Results: Of 1014 patients, 59% (601/1014) had positive RT-PCR results, and 88% (888/1014) had positive chest CT scans. The sensitivity of chest CT in suggesting COVID-19 was 97% (95%CI, 95-98%, 580/601 patients) based on positive RT-PCRresults. In patients with negative RT-PCR results, 75% (308/413) had positive chest CT findings; of 308, 48% were considered as highly likely cases, with 33% as probable cases. By analysis of serial RT-PCR assays and CT scans, the mean interval time between the initial negative to positive RT-PCR results was 5.1 ± 1.5 days; the initial positive to subsequent negative RT-PCR result was 6.9 ± 2.3 days). 60% to 93% of cases had initial positive CT consistent with COVID-19 prior (or parallel) to the initial positive RT-PCR results. 42% (24/57) cases showed improvement in follow-up chest CT scans before the RT-PCR results turning negative. Conclusion:Chest CT has a high sensitivity for diagnosis of COVID-19. Chest CT may be considered as a primary tool for the current COVID-19 detection in epidemic ar...

Background: Coronavirus disease 2019 (COVID-19) induces myocardial injury, either direct myocarditis or indirect injury due to systemic in ammatory response. Myocardial involvement has been proved to be one of the primary manifestations of COVID-19 infection, according to laboratory test, autopsy, and cardiac magnetic resonance imaging (CMRI). However, the middle-term outcome of cardiac involvement after the patients were discharged from the hospital is yet unknown. The present study aimed to evaluate mid-term cardiac sequelae in recovered COVID-19 patients by CMRI Methods: A total of 47 recovered COVID-19 patients were prospectively recruited and underwent CMRI examination in this study. The CMRI protocol consisted of black blood fat-suppressed T2 weighted imaging (BB-T2WI), T2 star mapping, left ventricle cine imaging, pre-and post-contrast T1 mapping, and late gadolinium enhancement (LGE). Myocardium edema and LGE were assessed in recovered COVID-19 patients. The left ventricle (LV) and right ventricle (RV) function and LV mass were assessed and compared with normal controls. Results: Finally, 44 recovered COVID-19 patients and 31 normal controls were included in this study. No edema was observed in any patient. LGE was found in 13 patients. All LGE lesions were located in the middle myocardium and/or sub-epicardium with a scattered distribution. Further analysis showed that LGE-positive patients had signi cantly decreased left ventricle peak global circumferential strain (LVpGCS), right ventricle peak global circumferential strain (RVpGCS), right ventricle peak global longitudinal strain (RVpGLS) as compared to non-LGE patients (p 0.05), while no difference was detected between the non-LGE patients and normal controls. Conclusion: Myocardium injury existed in about 30% of COVID-19 patients. These patients had peak right ventricle strain that decreased at the 3-month follow-up. Cardiac MRI can monitor the COVID-19-induced myocarditis progression, and CMR strain analysis is a sensitive tool to evaluate the recovery of left ventricle circumferential contraction dysfunction and right ventricular dysfunction.

The severity of the pulmonary manifestations of COVID-19 can be quantitatively evaluated from chest CT using a deep-learning method. There were significant differences in lung opacification percentage, as measured by the deep learning algorithm, among patients with different clinical severity. This automated tool for quantification of lung involvement may be used to monitor the disease progression and understand the temporal evolution of COVID-19. Abbreviations ARDS = acute respiratory distress syndrome, COVID-19 = coronavirus disease 19, GGO = ground glass opacity, HRCT = high resolution computed tomography, RT-PCR = reverse transcription-polymerase chain reaction, SARS-Cov-2 = severe acute respiratory syndrome coronavirus 2, SpO2 =pulse oxygen saturation

This is a repository copy of A global benchmark of algorithms for segmenting the left atrium from late gadolinium-enhanced cardiac magnetic resonance imaging.

Background-There are limited data on typical arrhythmogenic substrates and associated ventricular tachycardias (VT) in patients with nonischemic cardiomyopathy. The substrate location may have implications for the ablation strategy. Methods and Results-Nineteen consecutive patients with nonischemic cardiomyopathy (age 58±14 years, 79% men, left ventricular ejection fraction 41±11%) who underwent contrast-enhanced MRI and VT ablation were included. On the basis of 3-dimensional contrast-enhanced MRI-derived scar reconstructions, 8 patients (42%) had predominant basal anteroseptal scar, 9 patients (47%) had predominant inferolateral scar, and 2 patients (11%) had other scar types. Three distinct VT morphologies (≥1 of 3 inducible in 16/19 patients) were associated with underlying scar type. In 9 patients with anteroseptal scar-related VT (8/9 predominant scar, 1/9 nonpredominant), ablation target sites (defined as sites with ≥11/12 pacemap, concealed entrainment or VT termination during ablation) were located in the aortic root and/or anteroseptal left ventricular endocardium in 8 patients (89%) and in the anterior cardiac vein in 1 patient (11%), with additional target sites at the right ventricular septum in 2 patients (22%) and at the epicardium in 1 patient (11%). In contrast, in 8 patients with predominant inferolateral scar-related VT, target sites were located at the epicardium in 5 patients (63%) and in the endocardial inferolateral left ventricle in 3 patients (37%). Conclusions-Two typical scar patterns (anteroseptal and inferolateral) account for 89% of arrhythmogenic substrates in patients with nonischemic cardiomyopathy. Three distinct VT morphologies are highly suggestive of the presence of these scars. Anteroseptal scars were, in general, most effectively approached from the aortic root or anteroseptal left ventricular endocardium, whereas inferolateral scars frequently required an epicardial approach. (Circ Arrhythm Electrophysiol. 2013;6:875-883.)