Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is enlarged . There is upper zone redistribution and increased interstitial markings , as well as more confluent opacity at the left lung base , compatible with CHF . There is increased retrocardiac density consistent with left lower lobe collapse and / or consolidation . There is no gross pleural effusion , though small left effusion would be difficult to exclude . No pneumothorax detected .
    OUTPUT:
    
Cardiomegaly with CHF . Increased retrocardiac opacity consistent with left lower lobe collapse and / or consolidation .