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Chest Wall Deformities 333
Pectus Excavatum
Introduction
Pectus excavatum (PE), or funnel chest, describes a posterior depres-
sion of the lower sternum and costal cartilages into the thoracic cavity.
Cosmetic appearance is the main presenting reason in asymptomatic
patients. The asymmetrical depression is not unusual, and is associated
with sternal torsion.
Demographics
Pectus excavatum is an uncommon abnormality with an incidence of
38 per 10,000 and 7 per 10,000 births in the Caucasian and African Figure 53.3: Pectus excavatum severe deformity.
populations, respectively. It is four times more common in males than
females. A family history of PE is reported in 43% of patients, and
familial association is seen in 7% of patients with pectus carinatum . 3,4
The incidence of PC in our experience is equal to that of PE; however,
the literature suggests that it is less common than PE.
Aetiology
The sternal depression is thought to result from asymmetrical growth of
the costochondral cartilages. However, the exact aetiology is unknown.
There is an association with connective tissue disorders such as
Marfan’s syndrome (21.5%) and Ehlers-Danlos syndrome (2%). 3
Clinical Presentation
Thirty percent of PE patients present in early childhood, with the majority
presenting during the pubertal growth spurt. Common symptoms attrib-
uted to PE include exercise intolerance, dyspnoea, chest pain with and
without exercise, and palpitations. The majority of patients are healthy, Figure 53.4: Mixed deformity with the presence of a carinatum (protuberance)
and they present because of the cosmetic appearance (Figure 53.3). of the manubrium and excavatum of the sternum.
Patients often have a slouched posture, and young children have an asso-
ciated protuberant abdomen. Almost a quarter of PE cases are associated
with scoliosis, and hence the spine should be investigated in all cases.
Several variations in the sternal abnormality have been described.
A cup-shaped appearance describes an abnormality with localised,
steeply sloping walls. A saucer-shaped appearance is a diffuse and
shallow sternal depression. A long asymmetrical trench-like deformity
may also be found. Varying degrees of asymmetry of the chest wall
may be present. Sternal torsion may be clinically obvious. A mixed
carinatum/excavatum is an uncommon variation with the presence of
a carinatum (protuberance) of the manubrium and excavatum of the
sternum (Figure 53.4). 5
Investigations
Cardiac
Cardiac abnormalities have been known to be associated with PE Figure 53.5: Chest x-ray AP view showing shift of heart towards left and a line
and should be investigated in all cases with electrocardiography and across the chest (AB) that can be used to calculate the Haller index.
echocardiography. Compression of the right atrium and ventricle by
the depressed sternum has been implicated to cause mitral or tricuspid
valve prolapse in up to 17% of patients. This has not been our experi-
3
ence in the United Kingdom; however, we have rarely found associated
cardiac abnormalities in PE patients. Conduction abnormalities on
electrocardiogram (ECG), such as right heart block, first-degree heart
block, and Wolff-Parkinson-White syndrome, may be present in up to
16% of patients. 4
Respiratory
Respiratory function should be assessed preoperatively at least with spi-
rometry. Restrictive lung functions have been reported, with decreases
in forced vital capacity (FVC) of 77%, forced expiratory volume in 1
second (FEV ) of 83%, and forced expiratory flow during the middle
1
portion of expiration (FEF ) of 73%. It is useful to identify any
4
25-75%
underlying respiratory abnormalities prior to surgery, both for anaesthe-
sia and to see whether correction results in improvement.
Radiology
Chest x-rays, both anteroposterior (AP) and lateral, are routinely per-
formed, which may help to define the severity of the deformity as well Figure 53.6: Lateral chest x-ray showing the depth of sternal depression (CD).