The anatomic barriers in the coronary sinus: Implications for clinical procedures

Background: Coronary sinus (CS) catheterization is often used in cardiac resynchronization therapy. Failure to enter the CS is the most common reason for LV pacing lead implant failure. Methods: We evaluated the anatomic barriers, Thebesian and Vieussens valves, the CS and its tributaries in 52 adult human cadaver hearts. Results: The average diameter of CS ostiums was 9.47 mm. In 20 of the hearts heavier than 300 g, the average CS os diameter was 10.76 mm, whereas in the remaining hearts was 8.72 mm (p < 0.005). The Thebesian valves were observed in 35(67%) of the hearts. In 39(75%) of the hearts Vieussens valves were observed and noted that 6(11%) of them were qualitatively well developed and 33(63%) diminutive. Twenty cases (38%) had 3 vein branches, 19(37%) had 4 branches, 6(11%) had 5 branches, 6(11%) had 2 branches and 1(2%) had 6 branches between great and middle cardiac veins. The anatomic barriers in coronary sinus i.e., Thebesian and Vieussens valves and their branchings were evaluated and found optimal, suboptimal and worst for catheterization in 33, 15 and 4 Thebesian valves; 40, 8, 4 Vieussens valves, respectively. The coronary sinus tributaries between great and middle cardiac veins were found to be optimal, suboptimal and worst for catheterization in 88, 60 and 38 veins, respectively. Conclusions: Careful evaluation of anatomic barriers is important for treatment success. Thus, knowledge of these functional anatomic features and barriers allows for better utilization of the human coronary sinus for diagnostic and therapeutic purposes.