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.