Mid-term effects of implanting stents for relief of aortic recoarctation on systemic hypertension, carotid mechanical properties, intimal medial thickness and reflection of the pulse wave

Abstract

Primary implantation of stents is an accepted technique for treating aortic recoarctation, albeit that the effects of stenting on pressure profiles, carotid mechanical properties, intimal medial thickness, and reflection of the pulse wave have not been systematically investigated. Over the period from 1 January, 1999, to 31 December, 2002, we implanted stents to relieve aortic recoarctation in 15 patients, with a median age of 17 years, and a range from 7 to 29 years, with a median weight of 56 kilograms, ranging from 20 to 96 kilograms. Indications were a gradient of 20 millimetres of mercury or more measured in all, systemic hypertension at rest in 8, and systemic hypertension at exercise in all. Of the patients, 5 were receiving anti-hypertensive treatment. Before implantation of the stents, and after a mean follow-up of 22 months, all patients underwent an exercise test, vascular echography, and examination of the common carotid artery so as to determine its cross sectional compliance and distensibility, and the augmentation index. results: The stents were implanted successfully in all patients. The mean gradient was reduced from 27 to 4 millimetres of mercury (p < 0.001). Systolic blood pressure at rest diminished from 140 to 131 millimetres of mercury (p = 0.04), while hypertension at rest regressed in 4 patients. Systolic blood pressure at exercise diminished from 245 to 222 millimetres of mercury (p = 0.018), and hypertension at exercise regressed in 1 patient. Anti-hypertensive treatment is still required for 4 patients. A correlation was found between systolic blood pressure at rest and initial peak-to-peak gradient (r = 0.8), and between initial gradient and percentage reduction of systolic blood pressure at rest at follow-up (r = -0.73). Compliance and distensibility of the common carotid artery were not significantly modified, albeit that the intimal medial thickness diminished from 0.64 to 0.57 millimetres (p = 0.04), and the augmentation index decreased from 5 to -1 (p = 0.012). Primary implantation of stents is effective in mid-term repair of aortic recoarctation. Although there is an improvement in systemic hypertension, the tensional profile and vascular sonography are not normalized. At long term follow-up, the suppression of an early reflection site of the pulse wave could decrease the wall stress of the great elastic vessels, reducing the thickness of the arterial walls.