Coarctation of the Aorta (COA)

• Narrowing of the lumen of the Ao by ductal bump
• Constriction of the aorta at ductal area due to deformity in the media of the aorta

• Decreased blood flow through the aortic arch during fetal life

   

   

   

 COA and Echo

• Best view: supra sternal notch
• Look for Bi-leafet AoV
• Measure narrowing
• Color doppler 
• CW across narrowing
• Diastolic run-off doppler pattern in abdominal Ao

• PW and CW at Narrowest Point

COA Location

• Usually located just past the left subclavian artery and just opposite the PDA (Ao isthmus)

• Posterior shelf-like obstruction in the ductal region of the Ao
• Or complete tubular hypoplasia of Ao
• COA in transverse arch
• Abdominal Ao COA
• Rarely can be a part of many other left sided obstructions (Shone’s syndrome) 

COA Symptoms

• Symptoms usually begin to occur once the PDA starts to close
• Obstruction causes an increase afterload of LV:  LVH, LV failure, PHTN
• 2/3 of cases: Decreased or Impalpable femoral pulses , Systolic thrill (heard in SSN, and back)
• 46% have Bi-L AoV (make sure you document) 

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COA Associated Defects

• PDA 
• VSD
• Hypoplasia of Ao Arch
• In infancy: Prostaglandins are given to infants to maintain ductal patency to keep lower body perfused

Untreated COA

• Higher blood pressures in the upper extremities
• Lower blood pressures in the lower extremities
• If PDA is open, adequate lower extremity profusion will be maintained
• Can have organ failure if COA is severe and there is no perfusion to the organs
• Adolescents and adults: may have developed prominent collaterals

COA Surgery

• Risk of reoccurrence or aneurysms

Resection End-to-End anastomosis

• The COA portion of the Ao is resected. The two ends of the Ao are then sutured together end to end

Synthetic Patch aortoplasty

• The coarcted portion of the Ao is resected and replaced with a synthetic patch or homograph
• Advantage is preservation of LSCA, but there is an elevated risk of aortic aneurysm later in life

Left subclavian artery patch (AKA Subclavian Flap Aortoplasty)

• A portion of the LSCA is excised and the artery is divided
• Artery is closed at the proximal end, the tissue resulting from the division of the artery is used to repair the COA
• Low rate of rejection or recurrence of COA
• Disadvantage: loss of the LSCA and impaired blood flow to the left arm

 S/P COA

• Stents can be placed to open up a re-COA area, can re-dilate the stented area as time goes on
• May balloon to open the narrowed repaired area