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Coarctation of the aorta is a narrowing of the aorta typically at the location of the ductus arteriosus distal to the left subclavian artery accounting for 5%-8% of all congenital heart defects. Intervention is paramount as this condition carries a 35-year mean survival and a 75% mortality by the median age of 46 if no intervention is undertaken. This activity outlines the evaluation and endovascular management of coarctation of the aorta and reviews the role of the interprofessional team in managing patients with this condition. Objectives: Identify the indications for catheter management of coarctation. Describe the equipment, personnel, preparation, and technique in regards to catheter management of coarctation. Summarize the appropriate evaluation of the potential complications and their clinical significance with catheter management of coarctation. Discuss interprofessional team strategies for improving care coordination and communication to advance catheter management of coarctation and improve outcomes. Access free multiple choice questions on this topic.

Coarctation of the aorta is a type of congenital heart disease that is relatively common compared to other congenital malformations, with an approximate incidence of 3 cases out of 10,000 live births. This pathology is described as a narrowing or stenotic region in which blood traverses from the ascending to the descending aorta. Most commonly, it presents as a well-defined stenotic region at the juxtaductal level. This defect is complex, as it can occur across a spectrum of ages, be associated with other congenital defects (patent ductus arteriosus, ventricular septal defect, bicuspid aortic valve, hypoplastic left heart syndrome), and present with a wide range of clinical manifestations. Coarctation of the aorta, first acknowledged by Morgagni in 1760, carries a poor clinical prognosis with a mean age of death at 34 years of age and a 75% mortality at a median age of 46, according to a well-documented autopsy study. Surgical intervention for coarctation of the aorta was first described in 1944. It was performed via open lateral thoracotomy by resecting the stenotic segment of the aorta with re-anastomosis of the resected ends. This intervention was associated with a high incidence of recoarctation. This led to the next intervention, the patch aortoplasty technique. This technique involved an incision across the stenotic region, with a prosthetic patch sutured across the incision. This led to a reduction in re-coarctation but was associated with a high incidence of aneurysmal formation, ranging from 20% to 40% of cases. Another procedure was developed to manage coarctation of the aorta. Subclavian flap aortoplasty involves incision of the left subclavian artery down to the aortic isthmus with anastomosis of this flap with the incision across the coarcted segment to increase the vessel lumen of the aortic segment. This procedure demonstrates a 23% recurrence rate, with some incidence of aneurysmal formation, and is rarely associated with exercise-induced left arm claudication.

Another procedure was developed to manage coarctation of the aorta. Subclavian flap aortoplasty involves incision of the left subclavian artery down to the aortic isthmus with anastomosis of this flap with the incision across the coarcted segment to increase the vessel lumen of the aortic segment. This procedure demonstrates a 23% recurrence rate, with some incidence of aneurysmal formation, and is rarely associated with exercise-induced left arm claudication. The extended end-to-end anastomosis is currently the preferred surgical approach for coarctation of the aorta in most centers worldwide, due to its relatively low re-coarctation rate of 4% to 13%. This intervention involves clamping the aortic arch proximally at the takeoff of the subclavian artery and distally at the coarctation segment. A surgical incision is made in the inferior part of the aortic arch, the coarcted portion is resected, and the end-to-end anastomosis is completed at the arch and descending aorta. An interposition graft technique is utilized in adult-sized patients and in those with a long coarcted segment of the aorta. The aorta is clamped proximally and distally to the coarcted segment, which is resected. In place of the resected segment, a tube graft composed of Dacron or an aortic homograft is secured by creating 2 surgical anastomoses. Transcatheter-based intervention utilizing balloon angioplasty of the coarcted segment was first utilized in 1982. Compared to the surgical techniques, however, there was a significantly higher re-coarctation rate in infants and a less pronounced rate in adolescents and adults in the long term. Further technological development, such as covered stents, has improved outcomes. This topic addresses the transcatheter management of coarctation of the aorta.

Endovascular stenting has minimized the invasiveness in the repair of coarctation of the aorta, but it does carry documented complications. The most feared and serious complication is the rupture of the aorta. Based on a large multicenter trial, it was calculated to occur in 1.6% of cases. Noted risk factors for aortic rupture include pre-dilatation balloon angioplasty, abdominal aortic location of the coarctation, and age over forty years of age. The creation of aneurysms has been reported post-stent intervention with an estimated incidence of around 5 to 9%. Etiologies of aneurysmal formation include overstretching from balloon dilatation of the vessel wall and diminished elastin fiber quantity with increased collagen content.[12] The contribution of stretching of the vessel wall leading to wall trauma and the above-described sequelae has been shown to be minimized with the use of covered stents in the COAST II trial.[13] Complications can involve the stent itself. Embolization and migration of the stent can occur. There is a tendency toward migration when an oversized or undersized balloon catheter is used. The stent may become lodged in the aorta or femoral artery, requiring the use of a lasso device to assist its retrieval back into the sheath. Restenosis has been documented in 13% to 31% of cases following balloon angioplasty. This occurrence was reduced to around 2.7% in a study using stenting. One etiology of this process is neo-intimal proliferation within the stent. Additional complications arise from femoral access, including limb ischemia and hematoma. These complications have been reduced by the utilization of vascular closure devices.[12]

The process of deciding which patients are appropriate for endovascular repair of aortic coarctation is challenging. This depends on numerous factors, including the patient's age, the presence of concomitant congenital heart defects, and the specific anatomy of the coarcted segment. As such, appropriate patient selection for intervention involves collaboration among adult congenital heart disease cardiologists, congenital heart disease cardiothoracic surgeons, and interventionalists. The multi-team approach to intervention management is referenced in the 2008 American College of Cardiology (ACC) and AHA guidelines. This is a class 1 level of evidence C recommendation. This coordination of care extends beyond the periprocedural period and includes the lifelong follow-up period. ACC and AHA provide a class 1 recommendation for lifelong follow-up with a cardiologist specializing in adult congenital heart disease.[15]

Patients with congenital heart disease, including coarctation of the aorta, have better outcomes when a multidisciplinary collaborative approach is undertaken. This collaborative effort must target the cardiac sequelae that may manifest during the treatment of coarctation. This enlists the required support of the following: Advanced cardiac imaging services to interpret anatomy pre- and post-procedure Interventional cardiologists to plan and execute an intervention Cardiac anesthesiologists to titrate appropriate anesthetic and monitor hemodynamics intraoperatively Pediatric or general adult cardiologists with expertise in congenital heart disease An effort to refine care for congenital heart disease, including coarctation of the aorta, has led the American Board of Medical Specialties to approve Adult Congenital Heart Disease (ACHD) as a subspecialty encompassing both adult and pediatric cardiology. Additionally, there are ACHD specialists who are not board-certified but have gained considerable experience and expertise prior to the establishment of board certification bodies in this field. In general, patients with complex congenital heart disease and those undergoing invasive management have better outcomes, including survival, when they are managed at specialized centers.[16]

Given the documented risks of aneurysm formation, restenosis, and late hypertension, clinical evaluation is recommended at approximately 4 to 6 weeks after the procedure. In this evaluation, clinical history and physical examination can elicit the recurrence of symptoms such as lower extremity claudication and potential physical exam findings of hypertension and radio-femoral delay. Additionally, clinical monitoring after the procedure includes measuring ambulatory or exercise blood pressure. This is recommended as some patients are normotensive at rest but become hypertensive upon provocation with exercise. Abnormalities found on these postoperative surveillance measures prompt follow-up imaging, such as preferred multiple-detector computed tomography (MDCT) or magnetic resonance imaging . MDCT is preferred in cases of an indwelling stent, resulting in a susceptibility artifact. Repeat angiography was once the preferred method for initial follow-up imaging, but that's no longer the case with the advent of advanced imaging modalities.[14]