Right Coronary Sinus Injection

Right coronary sinus injection

Right coronary sinus injection is done to check the position of origin of right coronary artery from the right aortic sinus when there is difficulty in engaging the right coronary ostium during attempted right coronary angiography. Sinus shot is also taken when the catheter gets wedged in the right coronary artery repeatedly with damping of the catheter tip pressure tracing, to exclude a right coronary ostial lesion. In this case, the sinus shot shows separate origin of the right coronary artery and the conus artery.

The right coronary artery has a proximal chronic total occlusion and it is a non dominant artery. Usually the conus artery is the first branch of right coronary artery and supplies anastomotic vessels to branches of left anterior descending coronary artery. They become important in cases of LAD occlusion. Catheter tip is marked by the red arrow and dye in the right coronary aortic sinus by the green arrow.

ST segment elevation in right precordial leads resembling Brugada pattern can occur when the catheter wedges in the conus artery. If the catheter is not withdrawn promptly, ventricular fibrillation can ensue.