Although some chest wall deformities such as Poland's syndrome, Cantrell's pentalogy, ectopia cordis, and axphysiating thoracic chondrodysplasia are rare, there are two that are fairly common: pectus excavatum and pectus carinatum. Because most physicians do not see many patients with these deformities, misconceptions and outdated information are frequently communicated to the family. This is unfortunate for the patients because the deformity may have tremendous psychologic effects. Recent studies confirm that these deformities are definite physiologic problems that can he reversed by surgery.
Although the cause of chest wall deformities is unknown, there are a number of theories. The family history is positive in at least 40% of the patients and these deformities are rare in blacks; therefore, they probably have some genetic basis. The genetic manifestation is unknown; however, it is generally accepted that abnormal growth occurs in the cartilages with excess lengthening, which depresses or elevates the sternum. An associated aseptic perichondritis has been described.1
In many patients this deformity, also called "funnel chest," is noted at birth although full recognition may not occur until a year or two later. By schix>l age the chest wall depression and associated "pot belly" are obvious Figure 1),
Pectus excavatum is more common in males than females and may be seen in association with Marfans or other syndromes.2 There may be associated scoliosis, although this is usually mild and rarely requires treatment.
Symptoms vary considerably and frequently reflect the patient's concern with the appearance of the defect. Some patients are only aware of the effect oí the defect postoperatively, as they had been accustomed to the lower level of physical activity. Easy fatigability is fairly common and chest pain, dyspnea on exertion, and palpitation are less common. Children in the early teenage years can be psychologically devastated by the defect and usually have a great desire to have it corrected. Occasionally adults will seek correction for the same reason even though they have no significant symptoms.
Figure t. Pectus excavatum preoperative^ in a 7-year-old male.
Figur· 2. Postoperative repair with STRiB.
Diagnosis can be made visually and, although chest wall depression is the most significant sign, deformities vary greatly. A pot belly is often prominent, especially in preschool children (Figure 1). Asymmetry occurs in approximately half of the patients and some have axial rotation of the sternum so that it faces toward the right. The depression is deepest near the xiphoid. A faint systolic murmur is frequently present but a mild degree of scoliosis is infrequent. Marian's syndrome is associated in a small percentage of patients and may not be rect>gntzable in preschtx)! or slightly older children.
Echocardiograms may demonstrate mitral valve prolapse, especially in patients with Marian's syndrome. Standard posteroanterior and lateral chest x-rays show sternal depression and cardiac displacement. Computerized tomography demonstrates the depression well and has been used recently to quantitate the extent of the deformity. i Electrocardiographic abnormalities are common, consisting primarily of right axis deviation and depressed ST segments.
More sophisticated studies, such as maximal work capacity determination using a cycle ergometer,4 demonstrate diminished exercise time and increased oxygen consumption in preoperative patients compared with postoperative studies. These findings support the hypothesis that restricted cardiac stroke volume and increased work of breathing is due to the deformity and can be relieved by surgery.
Measurements of cardiac output using right heart catheterization5 has demonstrated diminished cardiac output (averaging 38%) in preoperative patients during upright exercise. These findings are not demonstrable in patients tested in the supine position without exercise and account for the erroneous reports of no physiologic impairment in these patients. Angiocardiograms show compression of the right ventricular outflow tract. This compression is reflected physiologically in right heart catheterization pressures and pressure waves similar to those of constrictive pericarditis.
Figure 3. Pectus excavatum postoperatively.
Treatment is purely surgical. There are no studies to indicate that breathing exercises or weight lifting ameliorates the defect or its effects. Weight lifting may be detrimental in Marfan s syndrome.
Certain aspects of the surgical correction, mostly relating to minor technical details, are controversial. We feel that a transverse incision should be used in all patients because it is more cosmetic and allows adequate exposure. The author and his associates have used a transverse incision with elevation of all soft tissue layers of the chest wall in a single flap in more than 200 cases. This has been found to be superior to other incisions in speed of development, cosmesis, blood loss, and postoperative fluid collection. We also use suction drainage beneath the flaps for 48 hours. More important, we believe that a metal bar for internal fixation is advantageous with the benefits outweighing the risks and minor complications associated with its use. Internal fixation prevents paradoxical chest wall motion in the early postoperative period and maintains the sternum anteriorly until cartilage regeneration occurs to fix the sternum anteriorly (Figure 2). The entire deformed cartilage should be renuwed because failure to do so may result in the remaining portion of cartilage enlarging postoperatively and producing lumps in the chest wall. The postoperative appearance is usually excellent (Figure 3).
Figure 4. Computerized tomography scan preoperatively in a 7year-o/d male. Pectus index 7.0Í.
Figure 5. Computerized tomography scan postoperatively; same patient as Figure 4. Pectus index 2.57.
Preoperative and postoperative computerized tomography scans of a 7-year-old boy are shown in Figures 4 and 5. The preoperative pectus index was 9.01; postoperatively it was 2.34
There should be virtually no mortality associated with the procedure although all anesthetics and surgical procedures carry a risk, even if near zero. A slight temperature elevation is common postoperatively. Minimal atelectatic changes in the lungs may be seen if postoperative chest x-rays are routine. Pneumothorax occurs in less than 10% and often is so minimal that it requires no treatment. Wound separation and postoperative fluid collections are rare. The metal bar may migrate slightly and become visible in the subcutaneous tissues but is rarely problematic. The postoperative scar is usually minimal. The metal bar is removed by a brief outpatient procedure, usually one year later.
Figure 6. Pectus carinatum preoperative^/ in a 12-year-old female.
Long term problems are more significant. There can be varying degrees of recurrence but this is usually minimal and should not exceed 4%. To date we have reoperated on only two of more than 200 patients, both of whom had excellent final results. Some prominence in the upper sternal area occasionally occurs and defies explanation, as this area is not involved during surgery.
Pectus carinatum, or "pigeon breast," is closely related etiological Iy to pectus excavatum but is less frequently symptomatic. Similar to pectus excavatum, pectus carinatum appears at a later age and is usually not noticed until the early school years. Progression at puberty is common, and often occurs rapidly and to a striking extent (Figure 6).
Pectus carinatum may also be associated with Marfan's syndrome. Although the surgical correction is the same as with pectus excavatum, the recurrence of the deformity is unknown. It may recur, however, as an excavatum as it did in one of our two "recurrent" cases. We have not seen this recurrence when internal fixation is used. The physiologic derangements in pectus carinatum are minimal or nonexistent. However, the development of this deformity in young teenagers can be crippling as far as their body image is concerned. Surgery usually provides an excellent result (Figure 7).
Pectus excavatum and pectus carinatum deformities are not uncommon. Pectus excavatum is associated with definite demonstrable adverse physiologic effects. The psychologic impact of these deformities on the patient can be truly devastating. The clinician must realize the impact and importance of the advice given to patients and their families. Although correction of these deformities is a major surgical undertaking, it is well tolerated, safe, and usually produces a satisfactory result.
Figure 7. Pectus carinatum postoperatively; same patient as Figure 6. 24 years old.
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2. Smith DW Recognizable Rinenu ni Human .Mulfrmtuuinii. Philadelphia. WB S;iiinders. NW.
3. Hallet JA. Kramer SS. U-Hm;m SA: Use CT. scan inielectuinid'ríitieiil'-liif pectus excavatum sunsrrv: A preliminary report. . J Pediatr Surg 1987: 22:904-906.
4. Cahill JM. Va-X* OM. Robertson HT: A summary of preoperative and postoperative cardiorespiraron- performance in patients iinderüoint! pectus excavatum and carinatum repair. J Pediatr Sun; 1984: 19:4 KM H.
5. Reiser OD. Epstein SE, et al: Impairment of cardiac functions in patients with pectus excavatum. with improvement after operation. N Eng Med 1912; 287:267-272.