Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable view of the chest demonstrates low lung volumes , which accentuate bronchovascular markings . There is no pleural effusion . Retrocardiac opacities are noted . There is perihilar vascular congestion . Hilar and mediastinal silhouettes are otherwise unchanged . Heart is mildly enlarged . There is no pneumothorax . No focal consolidation . Sternotomy wires are noted , which appear intact . Aortic valve prosthesis is in place . Gastrojejunostomy and biliary stent projects over mid upper abdomen . Malpositioned Dobhoff tube has been removed .
    OUTPUT:
    
Low lung volumes . Perihilar vascular congestion . Retrocardiac opacity , likely atelectasis , or superimposed infection can not be excluded .