Images In Cardiology A Case Of A Mega Atrial Septal Aneurysm In A Case Of Tricuspid Atresia

Abstract

A five-year old boy was brought for evaluation of blue discoloration of lips and nails since birth. On ex- amination he had central cyanosis and grade 2 club-
bing. The apex was shifted outwards and downwards and had LV predominance. On auscultation, there was a single component first heart sound, a loud second
heart sound, an ejection systolic murmur 3/6 in inten-sity. A Transthoracic colour doppler 20 Echocardiogram was done which showed situs solitus, absent Rt AV connection, a small Rt outlet chamber (picture a), discordant VA connections, and a subvalver and valver Pulmonary stenosis having a peak instanta- neous gradient of70 rnm Hg. In addition, a huge aneu- rysm of the atrial septum (pictures b, c), arising from 2 cm of the atrial septum at Foramen Ovale level was seen.

In Tricuspid atresia the blood passes from the RA to the LA through a septal defect at the Fossa Ovalis level, although primum defects and sinus venosus de- fects have been known. Rarely the atrial septum is in- tact. In this unusual situation, a coronary sinus to left atrial fenestration or window provides access to the left side of the heart. The inter atrial septum may be re- strictive and an aneurysm of the.atrial septum may re-sult.This aneurysm may achieve spectacular proportions.