Introduction: The largest vein of the heart, the coronary sinus also acts as a gateway to the epicardium of the left ventricle. The venous system of the heart are often overshadowed by the presence of the arteries of the heart. The venous trunk extending from the vieussens valve to the coronary sinus ostium in the right atrium is called as coronary sinus. It is about 2-3 cms long. A tremendous increase in the electrophysiological procedures and transvenous implantations warrant a complete knowledge of the coronary venous system and its tributaries.

Materials and Methods:  About 50 adult human hearts were studied, which were obtained from the cadavers of the Institute of Anatomy, Madurai medical college, Madurai.(over a period of 3 years) They were dissected and the formation, course, tributaries and termination of the coronary sinus were studied in the specimens.

Result: The great cardiac vein and the middle cardiac vein were present in all the specimens. Small cardiac vein was present in 96% of the specimens and was absent in 4% of the specimens.

Conclusion: The utmost important vein of the heart is the coronary sinus. The tributaries of the coronary sinus are Great cardiac vein, middle cardiac vein, small cardiac vein, posterior vein of the left ventricle and oblique vein of the left atrium. The complete knowledge of the anatomy of the coronary sinus and its tributaries are of great importance in the field of interventional cardiology.

Keywords: Great cardiac vein, oblique vein of Marshall, coronary ostium, middle cardiac vein, interventricular septum.

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Dr K. Vidulatha

Assistant Professor of Anatomy, Institute of Anatomy, Madurai Medical College, Madurai Tamilnadu, India