Topographic analysis of the coronary sinus and major cardiac veins by computed tomography

BACKGROUND The coronary sinus (CS) and its branches may play a role in the genesis of various arrhythmias. Applications of radiofrequency energy within the CS may be necessary. Atrio-esophageal fistula has been recognized as a complication of ablation along the posterior left atrial wall. OBJECTIVES The purpose of this study was to describe the in vivo topographic anatomy of the CS, esophagus, and coronary arteries using computed tomography (CT). METHODS Helical contrast CT of the heart with three-dimensional and endoscopic reconstructions was performed in 50 patients (28 men and 22 women mean age 54 +/- 10 years), The images were reformatted to determine the relationships among the CS. adjacent blood vessels, and esophagus and to determine the nature and thickness of surrounding tissue layers. RESULTS Mean CS ostium diameter was 12 4 mm. and mean thickness of the periosteal fat layer wits 3 2 mm. In 40 of the 50 patients (80%). the esophagus was adjacent to the CS, starting 24 +/- from the ostium, and remained in contact for a mean length of 7 +/- 5 mm. Mean thickness of the fat layer between the esophagus and CS was 1 +/- 1 mm, and mean thickness of the anterior wall of the esophagus was 3 +/- 2 mm. In 10 patients (20%). there wits no contact between the esophagus and CS, In 40 patients (80%), the right coronary artery was less than 5 mm front the CS (minimum distance 1 +/-1 mm) over a mean length of 17 +/- 11 mm, In all patients, the circumflex artery wits less than 5 mm from the CS (minimum distance 1 +/- 0.4 mm) over a mean length of 16 +/- 9 mill in patients with right-dominant coronary circulation and over it mean length of 86 +/- 11 mm in patients with left-dominant coronary circulation. CONCLUSION The CS often lies very close to the esophagus and coronary arteries. During radiofrequency energy ablation in the CS, caution should be exercised to prevent injury to surrounding structures.