Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A portable upright AP radiograph of the chest demonstrates bilateral lower lobe heterogeneous opacities . The lungs are otherwise clear . There is moderate cardiomegaly . There is no pneumothorax or pleural effusion . Pulmonary vascularity is normal . No subdiaphragmatic free air is seen .
    OUTPUT:
    
1 . Bilateral lower lobe heterogeneous opacities may represent atelectasis . Correlate with clinical picture to exclude pneumonia . 2 . No free air under the diaphragm 3 . Moderate cardiomegaly .