Echocardiographic diagnosis of coronary sinus type atrial septal defect. A case report

Coronary sinus type atrial defect is the result of an incomplete formation of the atriovenous fold. This is a rare anomaly that in a very few cases took advantage of echocardiographic diagnosis before surgery. We report on a case of coronary sinus type atrial septal defect diagnosed by means of transthoracic and transesophageal echocardiography.

A 65 year old woman who was admitted to hospital for evaluation of dyspnea and pre-syncope. A diagnosis of secundum type atrial septal defect had been achieved few months before. METHOD DESCRIPTION: Color Doppler transthoracic echocardiography demonstrated evidence of left-to-right shunt through the coronary sinus-left atrium common wall, while transesophageal echocardiography showed a defect in the coronary sinus roof in its terminal portion, proximal to the atrial septum. At that level the shunt flow was demonstrated by the presence of a negative contrast after contrast injection. Both transthoracic and transesophageal contrast echocardiographies demonstrated the persistence of a left superior vena cava draining into the enlarged coronary sinus: the existence of a right-to-left shunt at the coronary sinus level suggested by transthoracic echocardiographic examination was not confirmed by transesophageal echocardiography.

This is one of the few reported cases of coronary sinus type atrial defect diagnosed noninvasively and the diagnostic usefulness of both transthoracic and transesophageal echocardiographic approaches is stressed.