Hospital Medicine

Coarctation of the aorta

Jump to Section

Coarctation (CoA) of the aorta

I. What every physician needs to know.

Coarctation of the aorta is a stenosis found in the region of the ligamentum arteriosum. It can vary in location. It is usually discrete but should be thought of as a diffuse vascular disease. Besides hypoplasia of the aortic arch and the para-coarctation of the aorta, CoA can include the coronary arteries and the conduit arteries (radial, brachial and carotids). Atherosclerosis seems to appear earlier in CoA patients; Carotid intima-media thickness CIMT was found to be a useful tool in predicting cardiovascular risk, a fifteen fold higher risk was seen in patients with CoA with a CIMT exceeding 0.8 mm compared to controls.

CoA is also associated with the retinal bed, dissecting aneurysms, cerebral aneurysms, vascular rings, and systemic hypertension. Circle of Willis aneurysms and corkscrew retina arteries persist even after resection of the coarctation. An association between intracranial aneurysms (IA) and aortic pathology have been previously established; a more site specific correlation of the IA and the aortic pathology was described, suggesting a shared mechanism and possible genetic factors playing a significant role.

Proximal coarctation is a high pressure but low velocity segment and distal is a low pressure but high velocity segment. The distal segment is the one that becomes aneurysmal.

II. Diagnostic Confirmation: Are you sure your patient has coarctation of the aorta?

Coarctation can be defined as upper extremity hypertension with an associated significant gradient of at least 20mmHg between the upper and lower extremities. If there is significant collateral circulation then there may be little or no pressure gradient.

Other congenital defects can be associated with coarctation and include bicuspid aortic valve, intracranial aneurysms, anomalies of the brachiocephalic circulation, anterior and posterior collateral circulation involving the internal mammary and the intercostal arteries, aortic medial disease in the para-coarctation aorta and in the ascending aorta, aortic arch hypoplasia, ventricular septal defect, sub-aortic stenosis, mitral valve abnormalities, and patent ductus-arteriosus.

A bicuspid aortic valve is the most commonly associated defect with a rate of close to 80%. Circle of Willis aneurysms can occur at a rate of 2-10%. Coarctation can be diagnosed if there is proximal hypertension with echocardiographic or angiographic evidence of a coarctation of the aorta.

A. History Part I: Pattern Recognition:

No clear etiology for the hypertension is currently agreed upon.

A neural theory, which involves the distensibility characteristics of the precoarctation aorta and the sensitivity of carotid sinus baroreceptors, takes into account the increase in collagen and decreased amount of smooth muscle in the pre-coarctation aorta. The theory proposes that hypertension is the result of readjustment of baroreceptors, and thus, the increased pressure proximally is required to maintain adequate flow to the distal organs.

A renal theory utilizes the fact that the hypertension is confined to the proximal segment of the coarctation, thus leading to renal hypoperfusion and increased renin-angiotensin- aldosterone activity.

Coarctation hypertension is not associated with vascular disease, hypertensive retinopathy, or toxemia of pregnancy.

Even after repair these patients will have abnormal responses to blood flow and nitroglycerin and increased vascular stiffness in the conduit arteries in the upper body.

Abnormal arterial reactivity occurs via endothelial dysfunction as well as abnormalities in the muscular wall of the arteries.

The hypertension of coarctation is a risk factor of atherosclerosis of the coronary and conduit arteries.

B. History Part 2: Prevalence:

  • More common in males 1.5:1

  • Usually sporadic but more common with Turner syndrome patients and up to 30% have CoA, thus genetic testing is warranted in a female patient diagnosed with CoA.

  • Can be seen in maternal phenylketonuria syndrome and Kabuki syndrome

C. History Part 3: Competing diagnoses that can mimic coarctation of the aorta.

Hypertension from any other cause can always be a consideration. However, the physical findings particularly of a gradient between the upper and lower extremities should make it more obvious. Searching for a correctable cause of hypertension is always of the utmost importance even though coarctation in the adult is a rare finding.

D. Physical Examination Findings.

Upper extremity hypertension in conjunction with a diminished pulse pressure in the lower extremity should prompt a work-up for coarctation. Upper and lower extremity blood pressure measurements should be done checking for a delay between the radial and femoral pulses.

The presence of a systolic murmur in the intra-scapular region emanating from the coarctation can also be heard. Sometimes a widespread crescendo-decrescendo continuous murmur throughout the chest wall from intercostal collateral arteries can be heard.

Extreme tortuosity of the retinal arteries will be seen on funduscopic examination. Depending on the stage at which the coarctation is found there may be aortic stenosis or regurgitation as a result of a bicuspid aortic valve. In the presence of heart failure a third heart sound can also be encountered.

E. What diagnostic tests should be performed?

An electrocardiogram looking for left ventricular hypertrophy (LVH) should be done. If Turner syndrome is suspected chromosome analysis should also be done.

1. What laboratory studies (if any) should be ordered to help establish the diagnosis? How should the results be interpreted?

None

2. What imaging studies (if any) should be ordered to help establish the diagnosis? How should the results be interpreted?

A chest radiograph should be done to look for a "3 sign," which is caused by indentation of the aorta at the site of the aortic coarctation combined with pre and post-lesion dilatation of the aorta. Additionally, and classically, notching of the ribs caused by enlarged posterior intercostal arteries should be looked for. Anterior ribs are spared as the anterior intercostal arteries do not run in intercostal grooves.

Patency of the ipsilateral subclavian artery is necessary for the development of the thoracic collateral arteries. If the orifice of the subclavian artery is obstructed by the coarctation, left-sided collaterals fail to develop. A subclavian steal can result from retrograde flow down the ipsilateral vertebral artery.

Echocardiogram and Doppler studies can be done in adults but it is often very difficult to get the suprasternal arch view. Magnetic resonance imaging (MRI) and computed tomography angiography (CTA) may help delineate the coarctation as well as the presence of collaterals, associated vascular anomalies and flow abnormality.

If non-invasive tests are not sufficient then invasive angiography may be necessary to obtain the anatomy and the hemodynamics. If the patient is older than 40 years or if there is left ventricular dysfunction and due to the possibility of premature coronary artery disease, cardiac catheterization in these patients may be necessary.

Cerebral MRI or computed tomography (CT) should be done to rule out associated intracranial aneurysms. If Turner syndrome is suspected than appropriate chromosome analysis should be done.

F. Over-utilized or “wasted” diagnostic tests associated with this diagnosis.

NA

III. Default Management.

Given the significant long term complications of un-operated CoA, consensus dictates intervention; especially when hypertension is present and a greater than 20 mmgHg peak-to-peak pressure gradient is measured by catheterization or there is evidence of significant coarctation on imaging with collateral flow. With intervention 65% will demonstrate significant improvement in blood pressure. To minimize long-term complications of coarctation primary repair should be done in the pediatric age group.

Following repair in the child the obstruction is relieved with less than 1% mortality. Recurrent coarctation is more common when initially repaired in infancy. In the adult the most common surgical repair is resection of the coarctation with an end-to-end anastomosis, repair with a subclavian flap and a resection with a synthetic patch aortoplasty.

Unlike surgical repair in children, adults often are treated with angioplasty with or without stenting. The increasing use of covered stents in adults may possibly reduce the incidence of procedural complications such as rupture and aneurysm formation. Long-term outcome data for percutaneous intervention is currently lacking, but the COAST trial (Coarctation of the Aorta Stent) found that a Cheatham-Platinum stent was safe and effective with no deaths, low serious complication rate with a 12% fracture rate, and 2 years without any loss of stent integrity. Follow-up publication of intermediate outcomes was published in 2015 and demonstrated that stent fracture and progression of fracture have not resulted in clinically important sequelae; no patient with stent fracture has experienced stent embolization, and stent fracture has not been associated with identified aortic wall injury or hemodynamic re-obstruction; further analysis is still ongoing. Repeat intervention is common and related to early and late aortic wall injury and need for re-expansion of small-diameter stents. Stenting was found to be non-inferior to surgical repair in the acute and intermediate term follow-up for treatment of native CoA in adult population and should be considered for patients with suitable anatomy, longer term follow-up and comparison data are needed.

Greater than 25% of patients will develop hypertension if repair was done in late childhood or as an adult. While this problem can be associated with a re-coarctation it more likely represents the primary vascular disorder of coarctation. Percutaneous intervention is the treatment of choice in re-coarctation post-repair in which scar tissue may protect from aneurysm formation. In native coarctation there is more of a concern regarding aneurysm formation.

Complications of stenting include: re-coarctation, pseudoaneurysm formation, femoral artery injury, stroke, and aortic rupture. Leaking or ruptured aneurysm into a bronchus causing hemoptysis is life threatening, and requires immediate intervention.

A. Immediate management.

Control of blood pressure prior to work-up if possible.

B. Physical Examination Tips to Guide Management.

Since re-coarctation can occur, the patient should be monitored for a delay in the distal pulses and the detection of a significant difference in the upper and lower extremity blood pressures. The blood pressure needs to be evaluated since hypertension recurs often (50%). If the pressure is elevated again this will necessitate ruling out a re-coarctation. By physical examination an arm-leg differential pressure of greater than 35 mmHG has a high specificity for a hemodynamically significant re-coarctation.

C. Laboratory Tests to Monitor Response To, and Adjustments in, Management.

None

D. Long-term management.

When intervention is performed later there is a greater likelihood of persistent or recurrent hypertension. Usually there is no new gradient and the cause of the hypertension is felt to be multifactorial; including arch hypoplasia, abnormal aortic compliance, vascular stiffness, and abnormal baroreceptor function.

Systolic hypertension with exertion is also common but it is not a surrogate marker for re-coarctation. Re-coarctation can be caused by residual ductal tissue or by surgical scarring. Risk of re-coarctation is lower in those repaired later in life - less than 1%.

MRI or CTA should be done every 5 years to exclude re-coarctation or aneurysmal disease. Repair should be carried out if there is a greater than 20 mmHg gradient or a smaller gradient and hypertension. If there is no arm-leg pressure differential due to good collateral circulation but there is a greater than 20 mmHg gradient the coarctation should still be repaired.

Unlike native coarctation where stenting is controversial it is accepted for first line treatment in re-coarctation. Long complex lesion or those with a hypoplastic aorta may still require surgical repair.

E. Common Pitfalls and Side-Effects of Management.

Late left ventricular systolic dysfunction may occur. A diffuse arteriopathy in the upper part of the body seems to be present in a majority of patients. Late strokes may occur in adult patients who underwent surgery, and those with residual hypertension.

Finally, endocarditis can occur at the aortic coarctation site or associated lesions. While echocardiography may be helpful in the evaluation for residual or re-coarctation, the area is difficult to visualize especially if a stent or prosthetic material has been used for the repair.

IV. Management with Co-Morbidities.

All patients should be followed every 1-3 years. Close attention should be paid to residual hypertension. There is a high rate of hypertension late after coarctation repair, even in patients with unobstructed arches. The presence of retinal imaging abnormalities and left ventricular hypertrophy signals the presence of end-organ damage. Regular follow-up with 24 hour blood pressure monitoring is warranted. Heart failure, associated bicuspid aortic valve disease or an ascending aortopathy are all associated problems that need to be considered and treated appropriately. While not a co-morbidity, aortic pathology in pregnancy is well known. Ideally, coarctation repair should be undertaken prior to pregnancy.

If a Dacron graft was used in the repair then MRI or CTA should be done every 3-5 years to exclude subclinical aneurysm formation. These are no longer recommended since they can follow a malignant course, which is characterized by rapid growth, rupture and death.

A. Renal Insufficiency.

If contrast is to be used check blood, urea, nitrogen (BUN) and creatinine.

B. Liver Insufficiency.

No change in standard management.

C. Systolic and Diastolic Heart Failure.

Continue to monitor for either heart failure with preserved ejection fraction due to LVH, or from left ventricular systolic dysfunction.

D. Coronary Artery Disease or Peripheral Vascular Disease.

No change in standard management.

E. Diabetes or other Endocrine issues.

No change in standard management.

F. Malignancy.

No change in standard management.

G. Immunosuppression (HIV, chronic steroids, etc).

No change in standard management.

H. Primary Lung Disease (COPD, Asthma, ILD).

No change in standard management.

I. Gastrointestinal or Nutrition Issues.

No change in standard management.

J. Hematologic or Coagulation Issues.

No change in standard management.

K. Dementia or Psychiatric Illness/Treatment.

No change in standard management.

V. Transitions of Care.

A. Sign-out considerations While Hospitalized.

Sign-out as any for other cardiac catheterization patient.

B. Anticipated Length of Stay.

Overnight stay only for percutaneous repair of coarctation. For surgery anticipate 4-6 days.

C. When is the Patient Ready for Discharge.

Unless blood pressure is poorly controlled or there are wound issues the patient can be discharged and followed-up in an outpatient setting within 1 week.

D. Arranging for Clinic Follow-up.

Follow-up in 5-7 days post-procedure

1. When should clinic follow up be arranged and with whom.

5-7 days with cardiologist and or primary care physician.

2. What tests should be conducted prior to discharge to enable best clinic first visit.

None

3. What tests should be ordered as an outpatient prior to, or on the day of, the clinic visit.

None

E. Placement Considerations.

None

F. Prognosis and Patient Counseling.

Long-term blood pressure control may be an issue even with successful repair of the coarctation and follow-up imaging will be necessary on an every 3-5 year basis.

VI. Patient Safety and Quality Measures.

A. Core Indicator Standards and Documentation.

None

B. Appropriate Prophylaxis and Other Measures to Prevent Readmission.

Many patients with repaired coarctation have survived into adulthood but need to be followed regardless of the type of repair they had due to the persistent diffuse vascular dysfunction. This can predispose them to long-term complications including hypertension re-coarctation and aneurysm.

VII. What's the evidence?

Luijendijk, Paul, Lu, Huangling, Heynneman, Frederike B., Huijgen, Roeland, de Groot, Eric E.. "Increased carotid intima–media thickness predicts cardiovascular events in aortic coarctation". International Journal of Cardiology.. vol. 176. 2014. pp. 776-781.

Shin, Yong-Won, Jung, Keun-Hwa, Moon, Jangsup, Lee, Soon-Tae, Lee, Sang Kun, Chu, Kon, Roh, Jae-Kyu. "Site-Specific Relationship Between Intracranial Aneurysm and Aortic Aneurysm". Stroke.. vol. 46. 2015. pp. 1993-1996.

Yeaw, Xianglin, Murdoch, Dale J., Wijesekera, Vishvanatha, Sedgwick, John F., Whight, Christopher M., Pohlner, Peter G., Raffel, Owen C., Walters, Darren L.. "Comparison of surgical repair and percutaneous stent implantation for native coarctation of the aorta in patients ≥15 years of age". International Journal of Cardiology.. vol. 203. 2016. pp. 629-631.

Lee, Melissa G. Y., Allen, Sarah L., Kawasaki, Ryo, Kotevski, Aneta, Koleff, Jane, Kowalski, Remi. "High Prevalence of Hypertension and End-Organ Damage Late After Coarctation Repair in Normal Arches". Ann Thorac Surg.. vol. 100. 2015. pp. 647-53.

Meadows, Jeffery, Minahan, Matthew, McElhinney, Doff B., McEnaney, Kerry, Ringel, Richard. "Intermediate Outcomes in the Prospective, Multicenter Coarctation of the Aorta Stent Trial (COAST)". Circulation.. vol. 131. 2015. pp. 1656-1664.

Regitz-Zagrosek, V., Lundqvist, C. Blomstrom, Borghi, C.. "ESC Guidelines on the management of cardiovascular diseases during pregnancy". Eur Heart J.. vol. 32. 2011. pp. 3147-3197.

Krieger, E, Stout, K.. "The adult with repaired coarctation of the aorta". Heart.. vol. 96. 2010. pp. 1676-1681.

San Norberto Garcia, E, Gonzalez-Fajardo, J, Fernandez, B, San Roman, A, Vaquero, C.. "Open surgical repair and endovascular treatment in adult coarctation of the aorta". Ann Vasc Surg.. vol. 24. 2010. pp. 1068-1074.

Wheatley, G, Koullias, G, Rodriguez-Lopez, J, Ramaiah, V, Diethrich, E.. "Is endovascular repair the new gold standard for primary adult coarctation?". Eur J Cardiothorac Surg.. vol. 38. 2010. pp. 305-310.

Hager, A, Bildau, J, Kreuder, J, Kaemmerer, H, Hess, J.. "Impact of genomic polymorphism on arterial hypertension after aortic coarctation repair". Int J Cardiol.. vol. 151. 2011. pp. 63-68.

Silversides, C, Kiess, M, Beauchesne, L, Bradley, T, Connelly, M, Niwa, K, Mulder, B, Webb, G, Colman, J, Therrien, J. "Canadian Cardiovascular Society 2009 Consensus Conference on the management of adults with congenital heart disease: Out flow tract obstruction, coarctation of the aorta, tetralogy of Fallot, Ebstein anomaly and Marfan's syndrome". Can J Cardiol.. vol. 26. 2009. pp. e83-85.

Webb, G.. "Treatment of coarctation and late complications in the adult". Semin Thorac Cardiovasc Surg.. vol. 17. 2005. pp. 139-142.

Perloff, J.. "The variant associations of aortic isthmic coarctation". Am J Cardiol.. vol. 106. 2010. pp. 1038-1041.

Rosenthal, E.. "Coarctation of the aorta from fetus to adult: curable condition or life long disease process?". Heart.. vol. 91. 2005. pp. 1495-1502.

Wilson, W, Osten, M, Benson, L, Horlick, E.. "Evolving trends in interventional cardiology. Endovascular options for congenital disease in adults". Can J Cardiol.. vol. 75. 2014. pp. 86.

Ringel, RE, Gauvreau, K, Moses, H, Jenkins, KJ.. "Coarctation of the Aorta Stent Trial (COAST): study design and rationale". Am Heart J.. vol. 164. 2012. pp. 7-13.

You must be a registered member of Psychiatry Advisor to post a comment.

Sign Up for Free e-newsletters