The role of cardiovascular computed tomographic angiography for coronary sinus mitral annuloplasty

Background: The coronary sinus (CS) travels in close proximity to the left circumflex (LCX) artery. Percutaneously placed CS devices used to treat mitral regurgitation (MR) therefore have the potential to impinge upon the LCX arterial distribution and compromise coronary flow. Objectives: In this study, we sought to analyze the anatomic relationship between the CS, LCX and mitral annulus (MA) in patients with right dominant (RCD), left dominant (LCD) and codominant (CCD) arterial systems using a novel systematic approach. Methods: We retrospectively studied 102 normal patients (46 females) and 27 consecutive patients (5 females) with ischemic severe MR. All patients underwent cardiovascular computed tomographic (CCT) angiography with a 64 multidetector scanner for clinical indications. Images were analyzed using a GE Advantage workstation, version 4.4, capable of advanced image processing and manipulation. Results: In patients with a normal mitral valve, the LCX initially crossed under the coronary sinus/great cardiac vein (CS/GCV) in 74% with RCD, 83% with LCD and 97% with CCD. In patients with ischemic severe MR, the LCX initially crossed under the CS/GCV in 96%. Conclusions: The majority of patients, especially those with a CCD, have the LCX initially coursing under the CS/GCV. CCT data analysis using our newly established method is an excellent tool to evaluate the anatomic course of the LCX in patients being evaluated for percutaneous CS device placement.