For coarctation of the aorta in infants younger than three months
Authors: Ilic Slobodan , Vukovic Irena , Hercog Djordje , Vucicevic Milan , Parezanovic Voja , Vukomanovic Goran , Djukic Milan , Jovanovic Ida , Simeunovic Slavko , Lackovic Vesna , Todorovic Vera 
Published: May 2015

INTRODUCTION. Recurrent coarctation is a complication which is seen at a
consistent rate following repair for coarctation of the aorta in young
infants. OBJECTIVE. This retrospective analysis was carried out to compare
the results between resection with end-to-end anastomosis (ETE), and
resection with extended end-to-end anastomosis (E-ETE), in this age group
during late follow-up period. The role of ductus arteriosus is not clearly
defined and the second objective of this study was to analyze intimal
thickening in aortic coarctation. MATERIAL AND METHODS. From 1999 to 2003, 45
patients less than 3 months of age un?derwent repair of aortic coarctation.
Mean age was 24 days (2-89 days), average weight was 3.5?0.6 kg (2.4-5.2 kg).
The method of repair was ETE in 14 (31.1%) patients, E-ETE in 29 (64.4%)
patients and other techniques were applied in 2 cases. Demographic,
morphometric, clinical and operative variables were analyzed for correlation
with recurrent arch obstruction. In order to characterize the components of
intimal thickening in coarctation, narrowed segments of aorta resected from
16 neonates during surgery were examined immunocytochemically and by electron
microscopy. For light microscopy, the specimens were dehydrated in graded
ethanol (70-100%), cleared in xylol and embedded in paraffin.
Immunocytochemical staining was performed in 5 ?m sections from
formaldehyde-fixed paraffin-embedded blocks, using a labeled
streptavidin-biotin method with an LSkit (Dako). RESULTS. Early mortality
was 6.7% (CI 95%, 2.9%-10.4%). All early deaths (3 patients) occurred in
infants with associated ventricular septal defects (p<0.05). The mean
follow-up for all patients was 30?21 months (range 1.5-63 months). During
mean follow-up of 2 months, recurrent arch obstruction was diagnosed in 9
patients (21.4%). Two patients with associated complex heart defects died
before reintervention, one had mild gradient on catheterization (20 mm Hg)
and one is waiting for catheterization. Five patients were reoperated and the
mean time to reintervention was 4 months (range 2.6-6 months). Kaplan-Meier
freedom from recoarctation was 78.1?6.4% at 5 years in the whole group.
Freedom from recoarctation was 60.6?15.4% at 25 months in ETE group and
86.2?6.4% at 60 months in E-ETE group (p=0.062). Factors associated with
recoarctation, obtained by univariable Cox regression, included abnormal
right subclavian artery (p=0.003), hypoplastic proximal transverse aortic
arch (Z?-2, p=0.025) and weight at op?eration ?3 kg (p=0.02). Abnormal origin
of the right subclavian artery was the only independent predictor of
recoarctation obtained by multivariable Cox regression analysis. DISCUSSION.
All examined specimens had intimal thickening of the posterior aortic wall,
with accumulation of smooth muscle cells (SMC) with ? smooth muscle actin
(?-SMA) and vimentin-immunoreactivity (but not desmin and MHC) and also
expressed PCNA and S-100. In the inner media of the anteromedial wall of the
aorta, all specimens had large number of SMC expressing desmin and MHC. SMC
in the inner media exhibit contractile phenotype and their origin could be
ductal. CONCLUSION. Both procedures are effective for coarctation repair in
young infants. Risk of recoarctation is a function of the complex anatomy of
the arch, while residual ductal tissue may play a significant role.