Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to the prior film , there is been resolution of the CHF . Mild residual upper zone redistribution may be present . There is minimal patchy opacity posteriorly , with patchy opacities in the right cardiophrenic region and in the retrocardiac region . No frank consolidation is identified . No pleural effusion . Cardiomediastinal silhouette is enlarged , possibly slightly improved . Left - sided 2 lead pacemaker is present , with tips over right atrium and right ventricle .
    OUTPUT:
    
1 . Minimal opacity at both lung bases . The appearance is compatible with bibasilar atelectasis , but the possibility of an early infectious infiltrate can not be excluded . No frank consolidation . 2 . Marked interval improvement in previously seen CHF findings .