A 35 year old woman, known to have heart disease, came with complaint of difficulty in breathing for the past two months. On auscultation, a pansystolic murmur was heard in the third left intercostal space.
The frontal chest radiograph shows cardiomegaly with a CTR of 70% with prominent right atrial border that is squared off resulting in a box shaped heart. There are reduced vascular markings suggestive of pulmonary oligemia.