Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: New , prosthetic aortic valve projects over the heart . Again seen are surgical clips overlying the right lateral chest wall , hemithorax , and neck . Cardiomediastinal and hilar contours are normal . Increased retrocardiac opacity likely reflects atelectasis . There is no pneumothorax . Blunting of the left costophrenic angle may suggest a small pleural effusion .
    OUTPUT:
    
New , left basilar atelectasis .