Abstract
In this chapter, coarctation of the aorta is reviewed from diagnosis to surgical management. The anesthetic and related surgical considerations are discussed using a patient with Turner syndrome as an example. Consideration for ductal dependent vs. non ductal dependent coarctation is made.
A 16-day-old female presents for a sedated echocardiogram. She was at the pediatrician for a well-child visit when the physician noted weaker femoral pulses compared with her radial pulses. Vital signs are: BPs: RUE: 98/60 LUE: 62/31 RLE: 66/32 LLE: 66/30; HR 126/min; RR 25/min; SpO2 100% on room air. Weight 4.2 kg. Physical examination was notable for excessive tissue over the posterior neck. Chest X-ray reveals prominent pulmonary vascular markings.
What Is Coarctation of the Aorta?
Coarctation is simply a narrowing of the aorta. Most commonly, the narrowing is present at the site of the ductus arteriosus attachment (or former attachment; Figure 60.1). Less commonly, the coarctation appears in the ascending aorta and is also known as a preductal coarctation. Coarctation may present in the neonatal period (first 30 days of life) or at any time following. Sometimes it is undiagnosed until later in life. Coarctation may be associated with other congenital heart defects, such as hypoplastic left ventricle (LV), ventricular septal defect (VSD), or atrial septal defect (ASD). Up to 30% of children with Turner syndrome have coarctation.
Figure 60.1 Pictorial illustration of aortic coarctation which can occur as illustrated or as a circumferential narrowing of the aortic lumen.
What Are the Clinical Manifestations of Turner Syndrome?
Turner syndrome is a genetic mosaicism in which part or all of an X chromosome is lost. These patients can be monosomy X or contain a chromosomal mosaicism (e.g., 45,X/46,XX). Common clinical signs are:
Wide-spaced nipples
Short stature
Congenital lymphedema of hands and feet
Webbed neck
Low hairline
Hearing loss
Ovarian insufficiency
Hypertension
Prolonged QT interval
Renal anomalies
Cardiovascular anomalies
Metabolic syndrome
What Are the Common Cardiac Issues Affecting Patients with Turner Syndrome?
Cardiovascular anomalies are exceedingly common in patients with Turner syndrome. In addition to coarctation, aortic valve anomalies, especially bicuspid aortic valves, are present in as many as 30%. These patients are also at a higher risk for progressive aortic dilation and aortic dissection.
What Are the Major Hemodynamic Consequences of a Preductal Coarctation?
Coarctation of the aorta essentially functions as an LV outflow tract obstruction. Severe coarctation may result in LV failure and poor distal perfusion.
Critical coarctation in infancy generally requires early intervention. The patient is stabilized with prostaglandin to promote ductal patency which allows for perfusion to the lower extremities. Inotropic agents are administered when needed to improve myocardial contractility, especially in the setting of heart failure.