Scimitar syndrome

[MIM 106 700]

(scimitar anomaly, Halasz syndrome, congenital venopulmonary syndrome, Felson venolobar syndrome)

Prevalence: between 1 to 3/100,000. Female predominance. Mutation on locus 4q12 in many patients.  Congenital malformation that consists of a partial pulmonary venous return of the right lung in the inferior vena cava or right atrium. It is usually venous blood coming from the lower part of the right lung, which is thus derived to the systemic venous return. However, the  venous return of the whole right lung is derived to the systemic venous system in 30% of cases. The name of scimitar syndrome comes from the convex shadow in the right lung field), similar to a turkish dagger, on imaging (AP X-Ray or angiography).

Associated clinical picture:

-        a variable hypoplasia of the right pulmonary arterial vascularization and of right lung (often bilobar)

-        a cardiac dextroposition related to the right pulmonary hypoplasia

Often associated clinical elements:

-        systemic vascularization of part of the right lung (lobar sequestration).

-        a cardiac malformation (25%): ASD, aortic coarctation, patent ductus arteriosus, tetralogy of Fallot, , VSD

More rarely: right diaphragmatic hernia or bronchogenic cyst.

The clinical presentation is variable: heart failure with pulmonary hypertension in the neonatal period, frequent respiratory infections (bronchodilators are poorly effective) or fortuitous finding depending on the importance of the left-right shunt.

For example,

-        association with hypoplasia of the right pulmonary artery without sequestration: few problems except   possible respiratory failure (associated with pulmonary hypoplasia)

-        association to a moderate hypoplasia of the right lung without sequestration: left-to-right shunt

-        absence of pulmonary hypoplasia with sequestration: real systemic arterio-venous fistula with risk of heart failure.




The  forms that are symptomatic before one year of age are often referred to as "juvenile" and have a very severe prognosis. Treatment: surgery or interventional catheterization, according to the associated anomalies.


Anesthetic implications:

according to the clinical presentation: heart failure; left-right 'fixed' shunt, obstructive syndrome poorly responsive to bronchodilators (lung hypoplasia). Echocardiography and SpO2 at room air. Risk of desaturation and hypotension when the patient is lying on his left side.


References : 

-         Chemin A, Bonnet D, Le Bourgeois M, Levy M, Delacourt C. 
Respiratory outcome in children with Scimitar syndrome. 
J Pediatr 2013; 275-9.

-         Wang CC, Wu ET, Chen SJ, Lu F, Huang SC, Wang JK et al. 
Scimitar syndrome : incidence, treatment and prognosis. 
Eur J Pediatr 2008; 167: 155-60.

-        Singh A, Sharma N.  
Anaesthetic Management of Scimitar Syndrome: A Case Report. 
The Indian Anaesthetists’ Forum – (http://www.theiaforum.org) Online ISSN 0973-0311, July 2010 

-        Alberti N, Espérable F, Stéphant E, Lamblin A et al.
Découverte fortuite d’un syndrome du cimeterre au cours d’une visite systématique: à propos d’un cas.
Médecine et Armées 2011 ; 40 : 111-4.

-        Hasan M, Varshney A, Agarwal P.
A case of scimitar syndrome: anaesthetic considerations regarding non-cardiac surgery.
Ped Anesth Crit Care J 2016; 4: 89-91

-        Sergin D, Tanatti B, Ulukaya S.
Positional oxygenation changes in an adult patient with Scimitar syndrome: a case report.
A&A Practice 2018; 11: 247-9


Updated: November 2018