Mechanism of elevated blood pressure in pediatric patients with repaired CoA / 中华胸心血管外科杂志

ABSTRACT

Objective:To monitor the blood pressure in pediatric patients with coarctation of the aorta (CoA) before and 8 years after surgery, and explore the mechanism of elevated blood pressure in pediatric patients with repaired CoA.Methods:A cohort of 23 pediatric patients who underwent CoA repair between January 2010 and October 2010 in Guangzhou Women and Children's Medical Center was studied. And 20 age-, sex-match patients with isolated ventricular septal defect (VSD) who underwent surgery at the same time, 20 age-, sex-match health patients with normal echocardiographic findings were included in the study. Systolic blood pressure (SBP), diastolic blood pressure (DBP), arm-leg SBP gradient, right carotid intima-media thickness (CIMT), serum transforming growth factor-β1 (TGF-β1) were monitored at baseline(1 day before surgery) and 8-year follow-up (8 years after surgery).Results:There were no differences in SBP and DBP among patients with CoA, patients with VSD and health children at baseline ( P>0.05). But at 8-year follow-up, 2 patients with CoA exhibited hypertension. Not only that, patients with CoA had higher SBP than patients with VSD and health children at 8-year follow-up ( P<0.05). Patients with CoA had higher arm-leg SBP gradient than patients with VSD and health children at baseline ( P<0.01). But there were no differences in arm-leg SBP among patients with CoA, patients with VSD and health children at 8-year follow-up ( P>0.05). Patients with CoA had increased CIMT and higher serum levels of TGF-β1 at baseline and 8-year follow-up ( P<0.05). The preoperative levels of CIMT and serum TGF-β1 in the patients with CoA were highly positively correlated with their levels at 8-year follow-up, respectively ( P<0.01). There was a strong correlation between the levels of CIMT and serum TGF-β1 in patients with CoA, both preoperatively and postoperatively ( P<0.01). The preoperative and postoperative levels of CIMT and serum TGF-β1 in the patients with CoA were highly positively correlated with SBP at 8-year follow-up, respectively( P<0.05). Conclusion:Although surgery can successfully cure the anatomical " stenosis" , patients with CoA have elevated systolic blood pressure than normal people and patients with simple congenital heart disease (such as VSD). And some of the patients with CoA suffer from hypertension at long-term follow-up, even they are normotensive preoperatively. It may be related to vascular remodeling, in which TGF-β signaling pathway may be involved. Monitoring CIMT and TGF-β1 in patients with CoA preoperatively may be significative for prediction for the levels of SBP postoperatively.