Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac silhouette size remains mildly enlarged with a left ventricular predominance . The aorta is tortuous and mildly calcified , unchanged . Enlargement of the pulmonary arteries is stable , compatible with underlying pulmonary arterial hypertension . Minimal streaky opacity in the retrocardiac region likely reflects atelectasis , but infection is not excluded . No large pleural effusion is present . No pneumothorax or pulmonary vascular congestion is visualized . Right humeral head prosthesis is noted .
    OUTPUT:
    
Minimal retrocardiac streaky opacity likely reflecting atelectasis but infection is not excluded .