Introduction
Coarctation of the aorta comprises approximately 5% to 8% of congenital heart defects and is often associated with valvular malformations.1 These defects are typically diagnosed early and are managed with surgical repair, balloon angioplasty, or endovascular stent placement. However, as the following case illustrates, complications can occur in this population despite early intervention.
Case
A 15-year-old male adolescent presented to the pediatric ED after repeated blood pressure (BP) checks by the school nurse revealed consistently elevated systolic and diastolic pressures. The patient’s hypertension was associated with symptoms of intermittent headache and light-headedness. His medical history was remarkable for a congenital aortic coarctation and a bicuspid aortic valve. The patient had undergone a subclavian flap repair prior to 1 month of age, followed by a balloon dilatation 1 year later for recurrent coarctation. The rest of the patient’s medical history was unremarkable, including normal renal function. He denied illicit drug or alcohol use, sexual activity, or trauma.
On evaluation, the patient’s cardiac examination revealed a regular rate and rhythm with normally split S2; there were no rubs, murmurs, or gallops on auscultation. He had normal and equal pulses of the upper and lower extremities bilaterally. The patient presented without cyanosis. He was alert and oriented with normal upper and lower extremity reflexes. The neurological examination, including cranial nerve, strength, and gait testing, was unremarkable. The gastrointestinal examination showed a soft, nondistended abdomen, with no pulsatile masses. There was no abnormal swelling of his extremities. Although the physical examination findings were unremarkable, the patient’s vital signs were concerning as BP in his right upper extremity was as high as 208/110 mm Hg, while BP in his right leg was 130/68 mm Hg.
The patient followed up with his cardiologist, who ordered cardiac magnetic resonance imaging (MRI). The MRI showed mild narrowing of the distal aortic arch with a minimal and clinically insignificant pressure gradient. Based on the MRI findings, the patient was referred to a pediatric nephrologist, who performed a 24-hour ambulatory BP evaluation. The results of this study showed the patient to have systolic hypertension at the 95th percentile for his age and height. Based on the patient’s athletic predilection, β-blockers were avoided, and he was instead started on the angiotensin-converting enzyme (ACE) inhibitor lisinopril, along with annual follow-up cardiac evaluation.
Discussion
The authors’ initial concern for this patient was the possibility of a recurrent coarctation causing a significant pressure gradient between the upper and lower extremities with associated symptoms. A review of the literature demonstrates such an occurrence is not uncommon in this patient population, especially in patients with a history of early intervention (ie, within the first year of life).2
Causes and Incidence
One of the factors believed to contribute to recurrent coarctation is insufficient growth versus retraction of the manipulated tissues over time. The rates of recurrence vary based on the initial technique used for repair. These recurrences have been found to be approximately 6% in patients who had subclavian flap repairs; 31% for those who had balloon angioplasty alone; and approximately 20% in patients who had aortic stenting.3-5 As seen in this case, balloon angioplasty is usually performed in patients requiring revascularization. However, up to 32% of these patients will require further intervention due to subsequent recurrence.6
Evaluation
Although emergency physicians (EPs) have numerous diagnostic modalities available to evaluate patients with suspected aortic coarctation, as long as the patient is in no acute distress, much of the work-up can be performed on an outpatient basis—in conjunction with the primary- and subspecialty-care team. Regarding appropriate imaging modalities, echocardiography with Doppler or 3D reconstruction of MR angiogram can be useful in detecting both anatomical abnormalities as well as the associated gradient dysfunction; computed tomography can be used for assessing the anatomy.7 All of these modalities can also be used to evaluate late-term complications of aortic coarctation pathology, including aortic aneurysms. To help ensure good outcome, the EP should always keep the possibility of recurrence in the differential when evaluating these patients, regardless of the number of previous interventions attempted.