LETTER:
To the Editor,
We acknowledge that the study in your journal titled, “Cardiac surgery
in patients with atrial isomerism: Long-term results and outcomes” by
Diego B. Ortega-Zhindón MD et al is brilliantly written and we agree
with the conclusion that patients with atrial isomerism must undergo a
rigorous evaluation to determine an adequate repair strategy,
considering univentricular RAI with a high possibility of morbidity and
mortality. However, we would like to add some points which would enhance
the quality of this article and help in achieving the aim of this study
which is to determine the clinical and surgical outcomes of patients
with atrial isomerism (AI) undergoing cardiac surgery.
Firstly, there were some key patient characteristics which were missing
in the original study. A single-centered cohort study from China
stratified patients not only on broad types of pulmonary venous
connections such as partial and total, but also on further types like
extra cardiac total anomalous pulmonary venous connection (TAPVC), intra
cardiac TAPVC and obstructed TAPVC.2 This cohort study
also included ventriculoarterial connection, interrupted IVC-azygous
continuation, interrupted IVC-hemiazygous continuation which were
missing from the original study.2 Inclusion of these
patient factors would have increased the validity of the original study.
Secondly, another study included a wide variety of other cardiac
procedures in patients with atrial isomerism, which the original study
did not include. These additional procedures included atrial spectomy,
arterial switch operation, coarctation repair-pulmonary arterial band &
Norwood stage 1 procedure.3 These procedures, if
studied by the authors of original study, would have helped us better
understand the long term impact of cardiac surgery in patients with
atrial isomerism.
Thirdly, in another study, some congenital anomalies such as Kartagener
syndrome, Digeorge syndrome, Down’s syndrome, Klippel Feil syndrome,
vertebral defects, anal atresia, cardiac defects, tracheo-esophageal
fistula, renal anomalies and limb abnormalities were considered which
were not present in the original study.4 Consideration
of these characteristics by authors of the original study would have
enhanced quality of the study.
Lastly, the authors in the original study stated that right atrial
isomerism was found to be dominant as opposed to left atrial isomerism
but a previous study stated that LAI is more common.5However several studies showed strong predilection for RAI suggesting
there may be racial differences in the expression of LAI and
RAI.6 Consideration of this factor by authors of
original study would have given a new dimension to it.