Enlarged Right Atrium Falsely Interpreted as a Mediastinal Mass: A Case Report

Right atrial dilation due to left heart disease is a common complication among adults. The present review aimed to describe a case of massively dilated right atrium in a female patient presenting with valvular heart disease and no atrial fibrillation. The results of chest X-ray revealed a large opacity filling the lower right hemithorax, falsely interpreted as a mediastinal mass. During the transesophageal echocardiography, severe enlargement of the right atrium was detected, and open mitral and tricuspid valve replacements were performed successfully.