Genetically transmitted malformation syndrome
characterized by congenital thenar hypoplasia and the association of a
congenital heart disease (ventricular and atrial septal defect) and upper
limb malformation (underdevelopment of bones and/or extra bones).
Atriodigital Dysplasia; Cardiac-Limb Syndrome; HOS; Heart-Hand
Syndrome, Holt-Oram Type.
Congenital disorder of digital and/or radial dysostosis
associated with congenital heart disease. First described in 1960 by Holt
and Oram in a four-generation family with atrial septal defects and thumb
Prevalence estimated at 0.95:100,000 live births. More
than 50% of cases are caused by new mutations (no parental inheritance).
Autosomal dominant, variable expression but
strong penetrance (90-100%). Mutation of the long arm of chromosome 12
(12q24.1). No sex predilection.
Holt-Oram syndrome is caused by mutations in the
transcription factor TBX5, which is critical for development of the heart and
upper limbs. No contributory environmental factors are known. A number of
syndromes phenotypically resemble Holt-Oram syndrome but arise from
Absent, bifid, hypoplastic, or triphalangeal thumb
associated with cardiac septation defects, classically atrial septal defect
(often with conduction defects) but also ventricular septal defect.
As well as dysostosis of the thumb, the Holt-Oram
syndrome may be associated with radial dysgenesis. Clinical presentation
depends on the severity of cardiac disease (atrial septal defect in 70%
of cases) but may include severe endocardial cushion defects, mitral valve
prolapse, and hypoplastic left heart syndrome.
An anesthesiology consultation is
recommended before elective surgery. Obtain a history and examine for signs
and symptoms suggestive of ventricular failure and cyanosis. Perform an
electrocardiogram (ECG) and echocardiography to define cardiac anatomy.
Cardiac catheterization may be indicated for complex lesions.
The anesthetic technique is dictated by
the presence of cardiac disease. Consider premedication, use measures to
limit increases in pulmonary artery pressure (prevent hypercarbia, maintain
PaO2). If the pulmonary and systemic circulations are in parallel as in
the hypoplastic left heart syndrome, strict attention must be paid to
maintaining the balance of flow to the pulmonary and systemic vascular beds,
primarily by manipulating pulmonary vascular resistance.
No specific drug contraindications
other than those dictated by individual cardiac lesions. Antibiotic
prophylaxis of endocarditis is recommended.
Aase Syndrome: Autosomal recessive syndrome characterized by
bilateral triphalangeal thumbs, radial hypoplasia, congenital hypoplastic
anemia, joint and skeletal deformities, delayed fontanelle closures, poor
peripheral vascular access, possible ventricular septal defect.
Cavanagh Syndrome: Rare anomaly of the upper extremities that
presents with unilateral or bilateral hypoplasia of the thenar eminence.
Typical clinical, radiographic, and electrophysiologic findings emphasize
the diagnosis. Differentiation from carpal tunnel syndrome is important to
prevent unnecessary surgical intervention. Electrophysiologic and
radiographic findings are necessary tools to establish a correct diagnosis.
Haas Malformation: Congenital thenar hypoplasia associated with
hand anomaly defined as complete and bilateral syndactyly, marked by six
metacarpals and digits and fingers flexion. Autosomal dominant ...