Right ventricle is filling during a right coronary injection

Right ventricle is filling during a right coronary injection

If the right ventricle is filling during a right coronary injection, what is the possibility?
Coronary cameral fistula draining into right ventricle. Coronary cameral fistula means a fistula draining from a coronary artery to a cardiac chamber.
Other type of coronary fistula is coronary arteriovenous fistula connecting a branch of a coronary artery to a coronary vein. Sometimes coronary artery branches can drain to the pulmonary artery. Alternatively anomalous coronary arteries can arise from the pulmonary artery. In this case the flow is reverse, into the pulmonary artery as the pressure is lower in the pulmonary artery. Collaterals from other coronary branches will drain to the pulmonary artery through this connection.