Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are severe diffuse bilateral interstitial and alveolar opacities , with mild cardiomegaly , concerning for pulmonary edema in the setting of acute CHF . Bilateral pleural effusions are presumed , but not large . No pneumothorax identified .
    OUTPUT:
    
Severe pulmonary edema is most likely cardiac in etiology . Bilateral pleural effusions are presumed , but not large .