Left atrial to coronary sinus fenestration (partially unroofed coronary sinus). Morphological and angiocardiographic observations.

Abstract

The necropsy findings and characteristic angiocardiographic appearance of left atrial to coronary fenestration are presented. This fenestration is probably a fonne fruste of the developmental complex previously described of termination of the left superior vena cava in the left atrium, atrial septal defect, and absence of the coronary sinus. The partially unroofed coronary sinus provides an alternate or accessory route for blood flow when the atrium has no other functional exit. The angiocardiographic diagnosis is facilitated by selective injection of contrast material in the left atrium (or pulmonary vein) or left superior vena cava when the cava connects to the coronary sinus and left atrium via the fenestration.