Comparing Lung CT in COVID-19 Pneumonia and Acute Heart Failure: An Imaging Conundrum

Abstract

Background Chest computed tomography (CT) provides an effective modality to evaluate patients with suspected coronavirus disease 2019 (COVID-19). However, overlapping imaging findings with cardiogenic pulmonary edema is not uncommon. Reports comparing the chest CT features of these diseases have not been elaborated. Thus, we aimed to show the difference between the low-dose lung CT findings of COVID-19 pneumonia and comparing them to those with acute heart failure (HF). Methods This retrospective analysis enrolled hospitalized patients with COVID-19 (n=10) and acute heart failure (n=9) that exclusively underwent low-dose chest CT scans within 24 hours of admission. Clinical and lung CT characteristics were collected and analyzed. Results The appearance of ground-glass-opacities (GGOs) has been recorded in all individuals in the HF and COVID-19 groups. There was no significant statistical difference between the two groups for rounded morphology, consolidation, crazy paving pattern, lesion distribution, and parenchymal band (P> 0.05). However, diffuse lesions were more frequent in HF cases (55.6% vs. 0%) than in COVID-19 pneumonia, which had a predominantly multifocal pattern. Notably, CT images in HF patients were more likely to have signs of interstitial tissue thickening, such as the interlobular septums, fissures, and peribronchovascular interstitium (55.6% vs 0%, 88.9% vs 20% and 44.4% vs 0%, respectively), as well as cardiomegaly (77.8% vs 0%), increased artery to bronchus ratio (55.6% vs 0%), and pleural effusions (77.8% vs 0%). Conclusions Major overlaps of lung CT imaging features existed between COVID-19 pneumonia and acute HF cases. However, signs of fluid redistribution are clues that favor HF over COVID-19 pneumonia.

Keywords: covid-19; heart failure; imaging; lung ct; pneumonia.

Figure 1. Characteristic findings of low-dose chest CT imaging in COVID-19 pneumonia found in our patients

A. Multifocal and bilateral rounded GGO with predominant peripheral distribution; B. Crazy paving pattern; C. Bilateral mixed GGO and consolidation with posterobasal predominance GGO = ground-glass-opacity

Figure 2. Typical imaging features in congestive heart failure

A. Cardiomegaly; B. Interlobular septal thickening; C. Fissural thickening; D. Mixed GGO and consolidation with a central distribution. Significant bilateral pleural effusion also existed; E. Increased artery-bronchus ratio; F. Peribronchovascular interstitial thickening at the lower lobe bronchus GGO:  ground-glass opacity