Coarctation of Aorta-Management Options and Decision Making

Abstract

Coarctation of the Aorta (CoA) is a congenital cardiac anomaly consisting of a constricted aortic segment with a prevalence of 5 to 8% of all Congenital Heart Defects (CHD). The classic CoA is located in the thoracic aorta distal to the origin of the left subclavian artery, at about the level of the ductal structure. Significant hypertension and/or congestive heart failure are indications of intervention. If hypertension (rather that heart failure) is the clinical problem, it is better to relieve the aortic obstruction promptly rather that attempting to “treat” hypertension with antihypertensive medications. Surgical relief of the aortic obstruction and catheter interventional techniques (balloon angioplasty and stents) are available alternatives. Since the introduction of surgical correction by Crafoord and Nylin and Gross and Hufnagel in early 1940s, surgical therapy has been the treatment of choice for aortic coarctation. Gruntzig’s technique of balloon angioplasty was adopted by Singer and Sperling and their associates to enlarge coarcted aortic segments in post-surgical recoarctation and native coarctation, respectively in early 1980s. This is followed by the application of the technique by other cardiologists to treat native CoA. The procedure consists of inserting a balloon angioplasty catheter across the site of coarctation and inflating the balloon with diluted contrast material. Both immediate and followup results are reasonably good. Residual and recurrent obstructions following surgery and prior balloon angioplasty are also amenable for balloon angioplasty. Despite reasonably good short-term and long-term results of balloon angioplasty, some problems remain and include restenosis, probability of aortic rupture, formation of aneurysms and inability to effectively treat long-segment tubular narrowing. Because of these and other reasons, endovascular stenting of aortic coarctation has gained acceptance over the last decade. The balloon catheter, with the stent mounted on it, is advanced over a stiff guide wire and positioned across the coarctation segment and the balloon inflated, thus implanting the stent. Most cardiologists use stents in adolescents and adults and restrict their use in younger children because of issues related to growth. Stent therapy appears to be an attractive method for treatment of native or recurrent coarctation, aneurysm formation following prior surgical or balloon intervention and for long segment hypoplasia. Role of covered stents to manage aortic coarctation is limited and are used when the assessed risk for development of aneurysm or dissection is high. A comparison of all available treatment modalities was made and while it is difficult to make a definitive statement, the overall data seem to indicate that transcatheter methods may be better than surgery. Selection of the method of therapy is largely based on the age at presentation and anatomy of the coarcted segment and surrounding structures; surgery for infants and long segment coarctations, balloon angioplasty for discrete native and post-surgical coarctations in children and stents for long segment coarctations as well as any type of coarctations in adolescents and adults seem to be the current trend.