Clinical Impact of Stent Implantation for Coarctation of the Aorta with Associated Hypoplasia of the Transverse Aortic Arch

The aim of this study was to explore the clinical impact of transverse aortic arch hypoplasia (TAH) after stent implementation for isthmal coarctation of the aorta (CoA). From a retrospective chart review, 51 children (median age 11.1 years) were identified who had TAH and a CoA stent implanted between 10/1995 and 4/2015. Arm-leg cuff blood pressure measurements, echocardiographic arch imaging, and 24-h ambulatory blood pressure monitoring, prior to and after stent implantation, were reviewed. At catheterization, peak systolic gradients across the CoA's were 25 mmHg before and 4 mmHg after stent implantation. At a median 37-month follow-up, echocardiographic imaging showed no significant catch-up growth in the transverse arch (median z-score; proximal and distal arch -1.54 and -1.99 vs. -1.78 and -1.63, p = 0.13 and 0.90). A trend to increasing systolic blood pressure (SBP) differentials between the right and left arms was noted (11 mmHg [prior to]; 16 mmHg [follow-up], p = 0.09). Age-adjusted percentiles for right arm SBP decreased from 99.7% prior to, and 87.6% in follow-up (p < 0.001). The median time to re-intervention was 5.6 years (95% CI [2.8, 7.8]) and the proportion of children using anti-hypertensive in follow-up was not significantly different before the implantation (38% [prior to]; 45% [follow-up]). Elevated right arm blood pressure persists after successful stent implantation in the setting of associated TAH and there appears to be no catch-up growth of the transverse arch with time. Medical management can be difficult and approaches to surgical arch augmentation or stent implantation should be considered to avoid unilateral arm hypertension.