Discussion:
The incidence of associated cardiac defects in patients with SIT is
nearly 4% (range from 0 to 10%), commonly with transposition of the
great vessels (1, 3, 4). The association of situs inversus totalis with
PAPVC is very rare (8). Individuals with isolated SIT are often
asymptomatic, and are usually diagnosed incidentally, or during routine
tests (2, 9, 10).Therefore, the recognition of such rare anomaly is so
important for preventing surgical mishaps such as when approaching
appendicitis in a patient with SIT (9, 10). When associated with SIT,
clinical presentation of PAPVC will be the same as when it is an
isolated lesion, and thus varies widely based on the degree of left to
right shunt and associated cardiac defects (11). The most encountered
form of left-sided PAPVC is that in which the left upper pulmonary vein
(or veins) drains via a vertical vein into the left innominate vein to
further drain into the right atrium (11). In our patient, the left
pulmonary veins were draining directly to the left-sided right atrium
with normal drainage of the right pulmonary veins to the left
atrium. Surgical repair is indicated for symptomatic PAPVC
patients and asymptomatic individuals in whom Qp:Qs is more than 1.5, or
have an evidence of right ventricular dilation (11). In such
circumstances, the surgeon should be aware of special aspects regarding
the anatomy of cardiac chambers to avoid any pitfalls.