Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since the prior study , the heart size is significantly enlarged , and globular in shape . This could be secondary to global cardiomyopathy or a pericardial effusion . The lungs are clear with no pleural effusion or pneumothorax . No pulmonary vascular congestion or edema .
    OUTPUT:
    
Significant interval increase in heart size compared to ___ , which could represent a pericardial effusion or global cardiomyopathy . No evidence of pneumonia .