Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is improved aeration of the right lung base . Compared to the prior study , with persistent left basilar atelectasis and pleural effusion , unchanged from the prior . A right chest wall pulse generator with dual pacemaker leads terminating in the right atrium and right ventricle is unchanged . Dense atherosclerotic calcifications in the aortic arch are again seen . There is no pneumothorax or new focal airspace opacity identified .
    OUTPUT:
    
Improved right basilar atelectasis , with persistent left pleural effusion and left basilar atelectasis .