A syndrome combining an atrioventricular septal defect
with a Dandy-Walker-like malformation and craniofacial malformations.
3C Syndrome (Cranio-Cerebello-Cardiac Dysplasia
Syndrome); Dandy-Walker-like Malformation with Atrioventricular Septal
Congenital genetic disorder first reported by D. Ritscher
and A. Schinzel in 1987.
Very rare (fewer than 30 cases worldwide). It seems to be
more frequent in Canadian Native Americans.
May result from a 3C mutant gene and/or an
Clinically evocated by the association of cardiac
malformations, cerebellar hypoplasia, and cranial dysmorphism. The association with
immunoglobulin deficiency (IgG2 and IgG4) was reported in one
patient. Chest radiographs may show multiple ossification defects.
Clinical features include head (macrocephaly,
hypertelorism, prominent forehead and occiput, down-slanting palpebral fissure,
depressed nasal bridge, low-set ears, narrow palate, short neck), central nervous system
(hydrocephalus, hypoplastic cerebellar vermis, posterior fossa cyst/dilated fourth
ventricle [Dandy-Walker malformation], cranial nerve palsies, nystagmus, truncal
ataxia and mild to moderate growth and psychomotor retardation), heart (wide
range of anomalies from cleft mitral valve to complete atrioventricular
defect), and skeleton (first rib aplasia, camptodactyly of fingers, hip dislocation,
hemivertebra, hypoplasia of terminal phalanges, micronychia). Other
clinical signs include hypospadias, coloboma of the iris and/or retina, congenital
glaucoma, optic nerve atrophy, malrotation of the gut, anal atresia,
hydronephrosis, and immunodeficiency.
It is recommended to review carefully the
neurological history (motor/mental milestones) and any complications that might have
happened during the administration of previous anesthesia. Assess neurological function,
particularly the cranial nerves and the cerebellar function. Also, the potential for
raised intracranial pressure (clinical, EEG, CT sacn) must be carefully evaluated. A
complete cardiac evaluation, including ECG, chest radiographs, echocardiogram, and cardiac
catheterization is highly suggested because of several reports of early death due to the
severity of the cardiac defect. Assess airway for difficulty with ventilation and tracheal
Techniques should be tailored according to the cardiac defect present and the surgical
procedure planned. Antibiotic prophylaxis for endocarditis and prevention of air embolism with
adequate intravascular hydration are mandatory. Patient may be uncooperative as a
consequence of mild mental retardation. Difficult airway may be anticipated with abnormal
facial appearance, enlarged occiput, and short neck. Possible risk of pulmonary aspiration must
be kept in mind. The presence of cranial nerve palsy increases the risk. Caution
must be used with supraclavicular brachial nerve block because of the possible aplasia of
the first rib. Ophthalmologic examination must be obtained to eliminate the presence of
Depends on the underlying cardiac
defect and the possibility of raised intracranial pressure from hydrocephalus. Muscle
relaxants should be avoided until airway is secured and ventilation confirmed.
Prophylactic antibiotics in case of cardiopathy as indicated. Avoid medications that can
increase ocular pressure in case of glaucoma (e.g., succinylcholine).
Hoo J, Kreiter M, Halverson N, et al: 3C (cranio-cerebello-cardiac)
syndrome: A recently delineated ...