Tributary of coronary sinus ?

Coronary sinusIt opens in the posterior wall of right atrium, in the posterior pa of coronary sulcus.Itopens in the right atrium between IVC and tricuspid orifices.Tributaries of coronary sinus are :i) Great cardiac vein :- Lies in the anterior interventricular groove. Left marginal vein drains into it.ii) Middle cardiac vein :- Lies in the posterior interventricular groove.iii) Posterior vein of left ventricle.iv) Small cardiac vein :- It lies in the posterior pa of coronary sulcus with RCA. Right marginnal vein may sometimes open into small cardiac vein, more often, however, right marginal vein opens directly into right atrium.v) Oblique vein of left atrium (vein of marshall) :- It is continuous above with ligament of IVC. These two structures are embryological remnants of left common cardinal vein (duct of cuvier).