Coarctation of the aorta


Coarctation of the aorta is a condition in which there is a narrowing of the aorta, usually located at the area where the ductus arteriosus used to insert. It has a prevalence of 4/10.000 births and accounts for ~5% of all congenital heart defects.

Risk factors include congenital abnormalities, Turner syndrome and inflammatory diseases (e.g. Takayasu`s arteritis).

The stricture causes left ventricular outflow tract obstruction, which leads to myocardial hypertrophy and potentially heart failure. In adults, it is a cause of cardiomyopathy and secondary hypertension.

SIGNS AND SYMPTOMS:

Patients may be asymptomatic for years if there is a patent ductus arteriosus, or may have symptoms early in life when the ductus closes.

Children may have different degrees of heart failure with its respective signs and symptoms (from mild cyanosis to shock).

Adult patients, in addition to hypertension, may have claudication of the extremities, different blood pressure and pulses between the upper and lower extremities and symptoms of heart failure.

DIAGNOSIS:

Transthoracic echocardiography is usually enough to establish the diagnosis. MRI or CT scan may also be used. Bicuspid aortic valve may be present in such patients.

Chest x-ray may show cardiomegaly (younger patients) or notching of the posterior ribs due to erosion caused by the collateral circulation or indentation of the aorta with dilation before and after the stricture (“3 sign”) . ECG may be normal.

Genetic testing for Turner syndrome may be indicated for girls with coarctation of the aorta.

TREATMENT:

Two main treatment options are available: balloon angioplasty and surgery.

Surgery is usually indicated for younger patients and neonates because they often present with dramatic hemodynamic dysfunction. Prostaglandin E1 (alprostadil) may be used to keep the ductus arteriosus open and avoid deterioration before the surgical treatment.

Surgery may also be indicated for adults with maximum instantaneous gradient  >20mmHg or <20mmHg with evidence of significant coarctation and collateral flow.

Balloon angioplasty may be preferred for older patients with milder disease and for those with recoarctation.

Either balloon angioplasty or surgery may be complicated by aortic aneurism or dissection, hypertension or recurrence (recoarctation).

SOURCES & FURTHER READING:

  1. Suradi H, Hijazi ZM. Current management of coarctation of the aorta. Glob Cardiol Sci Pract. 2015; 2015(4): 44.
  2. European Society of Cardiology. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases. European Heart Journal (2014) 35, 2873–2926.
  3. Brown ML et al. Coarctation of the Aorta Lifelong Surveillance Is Mandatory Following Surgical Repair. Journal of the American College of Cardiology. Volume 62, Issue 11, September 2013.
  4. Hamdan MA et al. Endovascular stents for coarctation of the aorta: initial results and intermediate-term follow-up. Journal of the American College of Cardiology
    Volume 38, Issue 5, 1 November 2001, Pages 1518-1523.
  5. Toro-Salazar OH et al. Long-Term Follow-Up of Patients After Coarctation of the Aorta Repair. Am J Cardiol 2002;89:541–547.