Identification of coronary sinus septal defect (unroofed coronary sinus) by color Doppler echocardiography

Abstract

Coronary sinus septal defect (CSSD) (unroofed coronary sinus) is a defect in the wall that divides the left atrium from the coronary sinus. It is frequently associated with persistent left superior vena cav8.l When it occurs in association with intracardiac anomalies, such as tetralogy of Fallot2 or tricuspid atresia, 3, 4 there can be significant residual right-to-left shunting through the defect in the early postoperative period, if it is not recognized at the time of repair. The echocardiographic detection of this anomaly depends on the identification of the wall between the left atrium and the coronary sinus. Although this may not be difficult in the case of a neonate who can be scanned from multiple windows with 5.0 and 7.5 MHz transducers, resolution of this thin wall in the older infant or child with 2.5 or 3.5 MHz transducers can be a formidable challenge. Using color Doppler flow echocardiography, we recently prospectively diagnosed coronary sinus septal defects in a 20month-old infant (case l), a 32-month-old infant (case 2), and a ‘I-year-old child (case 3). Fig. 1. Subcostal frontal view of a normal patient with a dilated coronary sinus (and persistent left superior vena cava). Note the presence of the coronary sinus roof (unlabelled arrows). cs, Coronary sinus; LA, left atrium; RA, right atrium; rpu, right lower pulmonary vein.