Discussion:
A right aortic arch with a left aberrant subclavian artery, as seen in
this patient, is the second most common form of vascular ring anomaly
after the double aortic arch1. In our case, the ring
was completed by a PDA running between MPA and ASA which is unusual
(Figure 2B).
The conventional approach is division of the ligamentum arteriosum or
PDA to relieve compression caused by the vascular ring allowing the
structures to retract away from the tracheo-oesophageal
complex2. This can be also achieved with minimally
invasive methods but with a higher chance of recurrence of symptoms
requiring re-intervention3. Translocation of the ASA
to the carotid artery via lateral thoracotomy has better outcomes than
the above approaches2,3 but this technique applies to
isolated vascular rings without coexisting intracardiac lesions and our
child had large septal defects that also required closure in the same
sitting. A single approach to treat vascular rings with intra-cardiac
defects that has a lower risk of re-intervention remains undescribed.
In our patient, a lateral thoracotomy approach was not considered in
view of co-existing intra-cardiac shunts. A dual incision approach
comprising of supraclavicular access and a sternotomy had obvious
disadvantages of increase in operative time with attendant morbidities
and 2 visible scars. Moreover, complete translocation of the ASA without
a CPB from sternotomy was risky as the ASA was posterior to the trachea
and oesophagus with chances of injuring the oesophagus during dissection
and mobilisation. In view of these, it was thought that a midline
approach using CPB was ideal because it gave access to the vascular
ring, increased safety and also provided the option of closing the
intracardiac defects. Besides, it also provided better access to
mobilise the ASA after exit from its tracheo-oesophageal relation.
Conclusion: To conclude, our single-stage and
single-incision approach has several additional advantages and early
result have been encouraging.
- It enabled total correction of vascular ring and also closure of
septal defects in a single stage and single incision.
- Complete removal of pulsatile blood flow posterior to the trachea and
oesophagus without injuring them.
- Minimal damage to the second and third part of the subclavian artery
which is associated with increased risk of vascular
compromises4.
- It was quicker, cosmetically superior and less morbid as compared to
other approaches5.
- It eliminated chances of the recurrence of symptoms due to transection
and reimplantation of ASA.