MORPHOMETRY OF CORONARY SINUS AND ITS ROLE IN CARDIAC CANNULATION

Abstract

Introduction:- The heart muscle (myocardium) is drained by a collection of veins that merge to form a large vessel called the coronary sinus. Most cardiac veins empty into the broad coronary sinus, measuring approximately 2-3 cm long. It can be found in the posterior atrioventricular groove between the left atrium and ventricle. This sinus terminates at the right atrium, between the openings of the inferior vena cava and the right atrioventricular orifice. The entrance of the sinus may be guarded by an endocardial fold, also known as the sinus valve of the coronary sinus or Thebesian Valve. This fold may be absent or partially/fully cover the sinus ostium.

Material & Method:- A research project was conducted at the Anatomy Department of Index Medical College, involving the collection of forty-five formalin-fixed heart specimens. A digital vernier caliper was utilized in millimeters to obtain measurements of the coronary sinus ostium. The recorded data, including the craniocaudal and transverse lengths, were then documented in Microsoft Excel.

Result:- In the present study, an evaluation was conducted on 29 hearts to determine the presence of the coronary sinus with a Thebesian Valve, while the remaining 16 were without it. The Craniocaudal Diameters and Transverse Diameters were recorded both with and without Thebesian Valve. The diameters were measured at 7.12±1.92 mm with a range of 1.02 mm to 12.01 mm, 9.01±1.9 mm with a range of 2.01 mm to 17.02 mm, 7.02±1.92 mm with a range of 2.01 mm to 18.41 mm, and 9.02±1.21 mm with a range of 2.69 mm to 19.11 mm, respectively. 

Conclusion: - The Thebesian Valve is a remnant from the embryonic stage that was originally the sinoatrial valve. Its function is to protect the coronary sinus ostium. Advanced interventional cardiac diagnostic and therapeutic techniques involve the insertion of a tube into the coronary sinus ostium. However, the Thebesian Valve has been reported to cause obstruction or failure of the coronary sinus cannulation.