Cardiomegaly with right atrial enlargement

Cardiomegaly with right atrial enlargement can be seen in tricuspid valve disease (stenosis or regurgitation). The large right atrium in Ebstein’s anomaly of tricuspid valve produces a similar picture. A huge right atrium can also be there in a restrictive cardiomyopathy like endomyocardial fibrosis. Right atrial enlargement causes rightward enlargement of the cardiac outline.