COMMENT
Successful transfer of the coronary arteries is the single most important step in the performance of the switch procedure for transposition of great arteries. While its effects are evident immediately at the termination of the procedure in almost all instances, subtle deficiencies become evident on follow up and manifest as poor ventricular function 1.
The Leiden Convention identified the prevalent coronary artery patterns encountered and remain the most widely followed coding system to date2. Moll et al similarly described the coronary artery patterns in a large cohort of 700 patients and identified 16 types with their relative frequencies 3. While no pattern of coronary anatomy per se is a contraindication for the switch procedure, these classifications and coding systems serve to prepare the surgeon on the technical modifications to be adopted while performing the operation.
Looping of coronary arteries is associated with poor outcome when they originate from a single ostium, while no significant risk has been reported in cases where the arteries take origin from separate sinuses4. Two ostia arising from a single sinus have been described by Moll et al and they identified it as one of the risk factors associated with poor outcome in the immediate post-operative period 3. This report describes a patient with double ostia from both sinuses hitherto undescribed in the coding systems. While origin of the circumflex artery from the RCA is not associated with incremental risk, the patient in this report would be at higher than usual risk of a poor outcome on account of his double ostia from the two sinuses 3. This situation was managed by adequate mobilization of the individual coronary arteries combined with higher seating of the right sided button on to the ascending aorta respecting the posterior looping of the circumflex coronary artery as described by Lacour-Gayet 5.
Identification of the coronary artery pattern in the individual case plays a key role in the successful performance of the switch procedure. Awareness of the pattern described in this report prepares the surgeon for the possibility of dealing with four ostia while performing the coronary transfer.