MediAI

Clinical Hook A 59-year-old man arrived at the emergency department because of progressively worsening bilateral leg edema. Although peripheral edema is commonly associated with chronic heart failure, the initial chest radiograph immediately attracted attention. Rather than pulmonary edema or left ventricular enlargement, the cardiac silhouette appeared dramatically enlarged toward the right side. His cardiothoracic ratio measured approximately 0.82 , indicating severe cardiomegaly. However, the enlargement was highly asymmetric. Instead of generalized cardiac enlargement, the right atrial contour dominated the cardiac silhouette, suggesting an unusual diagnosis rather than typical congestive heart failure. Further examination demonstrated: Newly diagnosed atrial fibrillation Functional tricuspid regurgitation Clinical signs of right-sided heart failure Preserved left ventricular systolic function These findings prompted comprehensive multimodality cardiovascular imaging, incl...