Magnetic resonance cardiac vein imaging: relation to mitral valve annulus and left circumflex coronary artery.

OBJECTIVES To evaluate in vivo anatomical relationships between the coronary sinus-great cardiac vein (CS-GCV), the mitral valve annulus (MVA), and left circumflex coronary artery (LCX) with cardiovascular magnetic resonance. BACKGROUND The CS-GCV has become an anatomical structure of interest because it provides a way of access to the heart for a number of interventional procedures. Previous reports demonstrate that the postulated close anatomical proximity of the CS-GCV to the MVA does not always hold true in patients, both in autopsy specimens and in vivo by computed tomography. METHODS In 31 participants (24 volunteers and 7 patients; 15 men; 42 +/- 19 years), cardiovascular magnetic resonance was performed for noninvasive evaluation of the coronary sinus and of the coronary arteries using whole-heart imaging and intravascular contrast agents. Three-dimensional reconstructions, standard orthogonal planes, and unprocessed raw data were used to assess CS-GCV anatomy and its relation to the MVA and the LCX along their entire course. RESULTS The CS-GCV was located behind the left atrium in all examined participants, at a minimum distance of 8.6 +/- 3.9 mm from the MVA. In 80% of the participants, the LCX crossed the CS-GCV inferiorly, between the CS-GCV and the MVA. The CS-GCV and the LCX had a parallel course for 26.2 +/- 23.0 mm, with great variability of location and length. In several participants, the CS-GCV had a long parallel course, but in other participants, the LCX crossed below the CS-GCV at a discrete point. CONCLUSIONS In all participants, the CS-GCV coursed behind the left atrium rather than behind the MVA. In the majority of the participants, the LCX coursed between the CS-GCV and the MVA. These anatomical relationships should be kept in mind when referring a patient for interventional procedures requiring the access to the CS-GCV, and cardiovascular magnetic resonance might provide important information for the selection of candidates for these procedures.