Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Mild cardiomegaly is unchanged . Mediastinal silhouette and hilar contours are stable . There is mild prominence of the central pulmonary vasculature without frank interstitial edema . Lung volumes are low with bibasilar atelectasis . There is slightly increased right infrahilar density which is improved compared to prior examination where there was a prior pneumonia . There is no large pleural effusion or pneumothorax .
    OUTPUT:
    
Central pulmonary vascular congestion without frank edema . Subtle density in the right infrahilar region is improved compared to prior examination where there was pneumonia . Infectious etiology is not excluded given the correct clinical circumstance . A lateral view if possible may be helpful for further characterization .