Vascular Rings & Sling

Seoul National University Hospital

Department of Thoracic & Cardiovascular Surgery

Vascular Rings

Introduction 1. Definition Anomalies of the great arteries that compress the trachea and/or esophagus

2. History Hommel : Description double aortic arch in 1737 Wolman : Compression syndrome by double arch in 1939 Gross : 1st. surgical correction of double aortic arch in 1945

* Frequent vascular ring Double aortic arch Right aortic arch with retroesophageal Lt. subclavian artery & ligamentum arteriosum Right aortic arch with retroesophageal ligamentum arteriosum

Vascular RingsClassification

• Edwards’ Hypothetic Double Aortic Arch

Anomalies of the Aorta

Position, course, composition A. Double aortic arch B. Double lumen aortic arch C. With Lt. aortic arch & Lt. upper desc. aorta 1. Aberrant right subclavian artery 2. Other aberrant brachiocephalic arteries a. Aberrant brachiocephalic arteries without compression of trachea b. Aberrant innominate or left common carotid arteries causing compression of the trachea 3. Ductus arteriosus sling 4. Subclavian steal D. Circumflex retroesophageal component E. Right aortic arch

1. Without retroesophageal component 2. With retroesophageal component

Pulmonary Artery System

Congenital anomaliesA. Anomalous origin of left pulmonary artery (“vascular sling”)B. Unilateral absence of pulmonary arteryC. Origin of one pulmonary artery from the ascending aorta

Abnormalities of the Aorta

Length, size, or continuity A. Cervical aorta

B. Hypoplasia of the aorta

C. Pseudocoarctation of the aorta

D. Complete interruption of aortic arch

Vascular Rings

Embryonic development

Vascular Rings & Slings

Pathophysiology• Maldevelopment of the embryonic aortic arche

s produces vascular rings/sling that may partially or completely encircle the trachea and/or esophagus, producing compressive symptoms.

• Tracheoesophageal compressive symptoms include respiratory distress, recurrent pulmonary infections, and dysphagia.

Vascular Rings & SlingsClinical feature 1. Symptoms and Signs * Presentation within 1st 6months of life * Expiratory wheeze, inspiratory stridor * Tachypnea, respiratory infection

2. Laboratory Findings * X-Ray : tracheal deviation, compression * Esophagogram : most useful, indentation * Bronchogram : rarely done * Aortography

3. Natural History * Incidence : 1~2% of CHD * Symptom before 6 months : severe, and fatal before 1 year * Symptom after 6 months : less & disappear or become mild

Double Aortic Arch

Morphology• The left arch is often narrower than the r

ight.• Uncommonly right arch may be smaller i

n its distal part, but it is rarely atretic.• Associated cardiovascular anomalies are

not common,but include TOF & TGA.• Vascular ring is present.

Double Aortic Arch

Morphology

Right Aortic Arch

Types

Double Aortic Arch

Pathology

Right Aortic Arch

Morphology 1. Without retroesophageal component (Type I) * There is not a vascular ring * Common in TOF & truncus arteriosus

2. With retroesophageal component 1) Mirror image branching & restroesophageal LA (Type II) * vascular ring is present, but rare 2) Restroesophageal anomalous Lt. subclavian artery & LA (Type III) * common type of vascular ring * loose, compression is uncommon * associated anomalies are rare 3) Retroesphageal anomalous Lt innominate artery (Type IV) * vascular ring is present, but rare

Right Aortic Arch

• A, Paired dorsal aorta showing the position of the seventh intersegmental artery before cephalad migration. B, Cephalad migration with regression of the left dorsal aorta. C, Incomplete cephalad migration resulting in LSA arising from ascending aorta.

Branching configuration

Left Aortic Arch

Morphology 1. Anomalous Rt. subclavian artery * Dysphagia lusorium * Rarely Rt. ligamentum arteriosum (vascular ring)

2. Lt. aortic arch and Rt. descending aorta * Combination with Rt PDA or DA, vascular ring is present * Associated CHD is more common

3. Ductus arteriosus sling * Anomalous vessel from Rt. pulmonary artery origin crossed to Lt between esophagus & trachea to join descending aorta

4. Abnormal course of innominate or Lt. carotid artery 5. Severe malrotation of the heart

Left Aortic Arch

Aberrant RSCA

Right Aortic Arch

Left ligamentum arteriosum

Right Aortic ArchLeft ligamentum arteriosum

Tracheal compression by innominate artery

Vascular Compression

Retroesophageal RSCA

Left Aortic Arch

Vascular Rings

Operative treatment 1. Indication : patients with significant obstructive symptoms

2. Technique of operation 1) Double aortic arch : Division at the junction (Lt approach) 2) Right aortic arch : Dissection complete and division of ligamentum arteriosum (Lt approach) 3) Left aortic arch : Dissection complete and division right ligamentum arteriosum (Rt approach)

3. Result * Low hospital mortality * Late survival and relief of symptoms are both excellent unless other associated anomalies * Rarely aneurysm formation

Kommerell's Diverticulum

Presentation• Approximately 40% of RAA cases are associated with a

n aberrant subclavian artery originating from a diverticulum, so-called Kommerell's diverticulum, which is formed by a remnant of the left dorsal aorta

• Most patients with RAA are asymptomatic, however, RAA and aortic diverticulum can be confused with acquired aortic diseases, leading to unnecessary surgical intervention

• Although rare, atherosclerotic changes of ASA and KA can lead to dissection or aneurysmal dilatation

Kommerell's Diverticulum

Characteristics• A rare condition that occurs in association with a left aortic arch

with aberrant right subclavian artery or a right aortic arch with aberrant left subclavian artery

• Burckhard F. Kommerell reported an aortic diverticulum in a patient who had LAA and ARSA in 1936

• The aneurysmal diverticulum of the descending aorta at the origin of ARSA is called Kommerell's diverticulum

• Anatomically, in a patient with RAA and ALSA, the left common carotid artery arises from the anterior of the ascending aorta, followed by the right common carotid artery, the right subclavian artery, and the ALSA that arises from Kommerell's diverticulum

Kommerell's Diverticulum

• Computed tomographic angiography viewed from back shows Kommerell diverticulum (arrow) and dilatation of presumed remnant of origin of left subclavian artery (arrowhead).

CT angiography

Kommerell's DiverticulumSurgical indications

• Indications were that the diameter of Kommerell's diverticulum was more than 50 mm in patients who had symptoms associated with Kommerell's diverticulum

Surgical techniques• Total arch replacement• Replacement of the descending aorta with aberrant subclavi

an artery–carotid artery transposition• Open stent grafting with the extra-anatomic bypass• Ligation of the aberrant subclavian artery, and reconstructi

on of the descending aorta

Vascular Sling

IntroductionDefinition Left pulmonary artery arises anomalously from the rig

ht pulmonary artery extrapericardially, form a sling around the trachea.

History Glaevecke & Doehle : 1stly recognized in 1897 Contro : Term vascular sling in 1958 Potts : 1st successful operation in 1954

Vascular Slings

Morphology 1. Left pulmonary artery is slightly smaller than the right. 2. Rarely right upper lobe artery may come off left pulmonary artery near its origin. 3. Tracheobronchial and pulmonary abnormalities * Trachea near bifurcation is usually narrowed. * 50% show narrowing of trachea secondary to complete cartilage ring. * Hypoplasia, hyperinflation, atelectasis 4. Other cardiovascular anomalies * 50% of cases are associated, left SVC, ASD, PDA, VSD 5. Noncardiovascular anomalies * relatively frequent, a wide variety

Pulmonary Artery SlingMorphology

Pulmonary Artery Sling

Clinical features 1. Symptoms and signs * 90% have significant symptom, present at birth or soon after. * Wheezing, stridor, choking, tachypnea, cyanosis 2. Laboratory findings * X-Ray : bowing and deviation of airway * Esophagogram : anterior indentation in lateral view * Tracheogram : used with or without bronchoscopy 3. Natural History * Significant obstruction : most die before 1 year of age * Late presentation : survival is possible without surgery, obstruction become less with growth

Pulmonary Artery SlingOperative treatment 1. Indication * If there are symptoms & signs of respiratory obstruction. * When symptoms are mild, surgery is not recommended

2. Technique * Left posterolateral thoracotomy without CPB

* Median sternotomy with CPB

3. Result * Survival : 50~60% * Relief of obstruction : prognosis is poor with diffuse anatomic tracheal stenosis

Pulmonary Artery Sling

Operation