(Chest. 2001;119:1957-1961.)
© 2001
American College of Chest Physicians
Severe Pectus Excavatum Associated With Cor Pulmonale and Chronic Respiratory Acidosis in a Young Woman*
Ravichandran Theerthakarai, MD;
Walid El-Halees, MD;
Seyed Javadpoor, MD and
M. Anees Khan, MD, FCCP
*
From the Pulmonary Division, St. Joseph’s Hospital and Medical Center (Drs. Theerthakarai, El-Halees, and Javadpoor), Paterson, NJ; and Seton Hall University (Dr. Khan), School of Graduate Medical Education, South Orange, NJ.
Correspondence to: M. Anees Khan, MD, FCCP, Chief, Pulmonary Division, St. Joseph’s Hospital and Medical Center, 703 Main St, Paterson, NJ 07503
 |
Abstract
|
|---|
Pectus excavatum has never been reported to cause
hypercapnic respiratory failure. In this report, we describe the first
such case in a young woman with severe pectus excavatum who presented
with chronic respiratory acidosis, pulmonary hypertension, and chronic
cor pulmonale. An extensive diagnostic workup failed to uncover any
other cause of respiratory acidosis, which led us to conclude that the
severe chest wall deformity and the resulting severe restrictive defect
were responsible for the development of chronic respiratory acidosis
and cor pulmonale.
Key Words: alveolar hypoventilation • cor pulmonale • pectus excavatum • respiratory failure
|
Introduction
|
|---|
Unlike
deformities of the spine, pectus excavatum rarely results in a
measurable impairment of lung function and is said to have never
produced hypoventilation and respiratory failure.1
A
MEDLINE search failed to identify a report of a patient who had
experienced respiratory failure attributed to pectus excavatum.
Congestive cardiac failure also is said to be almost unheard
of2
and has not been observed in extensive hemodynamic
studies.3
4
Some patients may show a decreased diastolic
filling of the right ventricle as a result of compression, but
pulmonary arterial and pulmonary wedge pressures have been
normal.3
4
We describe the case of a young woman with
severe pectus excavatum who presented with severe hypercapnic
respiratory failure, pulmonary hypertension, and chronic cor pulmonale.
|
Case Report
|
|---|
A 29-year-old Polish woman was admitted to St. Joseph’s
Hospital and Medical Center because of increasing dyspnea of 4 months’
duration followed by the appearance of swelling of both feet of 3
days’ duration.
The patient had been well until 4 months prior to hospital admission
when she started noticing dyspnea on moderate exertion such as walking
for one block or climbing one flight of stairs. Symptoms worsened over
the following months until she started experiencing shortness of breath
even at rest. There was no history of protracted cough, sputum
production, chest pain, or hemoptysis. A review of her
physiologic systems was unremarkable except for easy
fatigability during most of her adult life, which she ascribed to a
weak constitution. Her history was devoid of incidences of pneumonia,
tuberculosis, bronchial asthma, or hospitalization. She had resided in
the United States for 8 years and had worked for a garment factory
sewing buttons on dresses.
She described her development as normal during her childhood except for
being rather frail, which kept her from participating in sports. Only
around age 12 years did she become aware of the abnormal funnel-shaped
appearance of her chest, which she thought was strikingly different
from her friends. She described her siblings and other family members
as being devoid of any such deformities.
A physical examination showed a very thinly built, but lively and
intelligent, young woman in mild respiratory distress at rest with the
following physical characteristics: weight, 33.6 kg; height, 163 cm;
pulse, 102 beats/min; BP, 108/58 mm Hg; and respiratory rate, 24
breaths/min. An examination of the chest showed severe pectus excavatum
of the entire anterior chest wall with a straight back and mild
scoliosis of the thoracic spine. Jugular venous distention at a 45°
angle and bilateral pitting pedal edema were noted. Breath sounds were
diminished in the left lower lung field posteriorly without any
adventitious sounds. Prominent left parasternal heave, enlarged cardiac
dullness on percussion, loud P2, and a loud pansystolic
murmur at the pulmonic area were noted on cardiac examination.
Liver edge was palpable at 2 cm below the right costal margin.
Hepatojugular reflux was positive. A neurologic examination failed to
show any motor or sensory deficits, with normal deep tendon reflexes.
Laboratory data showed a hemoglobin level of 16.9 g/dL and a WBC count
of 5.1 x 103/µL with a normal
differential cell count. Serum chemistry levels were within normal
range, except for a serum HCO3 level of 40
mmol/L, and the results of a urinalysis were within normal limits.
Arterial blood gas studies on room air at rest showed the following:
pH, 7.38; PaCO2, 70 mm Hg;
PaO2, 44 mm Hg;
HCO3, 42 mmol/L; and arterial oxygen
saturation, 76% (alveolar-arterial oxygen gradient, 22 mm Hg).
An ECG (Fig 1
) showed sinus tachycardia with a rate of 116 beats/min, right-axis
deviation, right atrial enlargement, and an rSR' pattern in
V2 without ST-T segment changes. A chest
radiograph (Fig 2
, 3
) showed the entire heart to be displaced into the left hemithorax,
clear visible lung fields, and a severe pectus excavatum with a marked
reduction of the anteroposterior diameter of the chest. A CT scan of
the chest (Fig 4
) confirmed the severity of the pectus excavatum, reducing the space
between the sternum and the vertebral bodies to about 2 cm and
completely displacing the heart into the left hemithorax, which
compressed the left lower lobe and the left mainstem bronchus. A
high-resolution CT scan of the chest showed some interstitial changes
in the lower lung fields and cystic changes in the left lower lobe with
thickened pleura. Gallium scan findings were unremarkable. A
quantitative perfusion lung scan showed 72% of the perfusion to the
right lung and only 18% perfusion to the left lung. A
ventilation/perfusion lung scan showed a matched ventilation defect in
the left lower lobe. An echocardiogram and a transesophageal
echocardiogram showed severe pulmonary hypertension with no evidence of
atrial or ventricular septal defect. The right atrium and right
ventricle were dilated with reduced right ventricle systolic function
and moderate tricuspid regurgitation. The left ventricle showed a
normal ejection fraction with normal wall motion. Both the mitral and
aortic valves were normal. Pulmonary function studies (Table 1
) showed evidence of a severe restrictive defect (total lung capacity
[TLC], 35% of predicted). Volume-adjusted diffusing capacity was
mildly impaired (71% of predicted).
Cardiac catheterization showed both the right atrium and right
ventricle to be dilated with increased filling pressure of the right
ventricle, decreased right ventricular systolic performance, and severe
tricuspid regurgitation, severe pulmonary hypertension, increased
pulmonary vascular resistance, and significant pulmonary venous
desaturation. No intracardiac shunt was evident. The left atrium was
normal in size with normal pulmonary venous return. Mitral valve
prolapse was noted. Left ventricular systolic function was normal. No
branch pulmonary artery stenosis or pulmonary venous stenosis was
discovered. These findings are consistent with the diagnosis of cor
pulmonale. A workup for collagen vascular disease, including
antinuclear antibody, anti-DNA, complement level, and rheumatoid
factor, was negative. Thyroid studies (triiodothyronine, levorotatory
thyroxine, thyroid-stimulating hormone) were within normal limits. The
results of a fluoroscopic examination of the diaphragm and a sniff test
were normal, excluding a significant diaphragmatic dysfunction.
The patient was treated with diuretics, salt restriction, low-flow
oxygen, and bilevel pressure ventilation, which resulted in
improvement in dyspnea, pedal edema, and arterial blood gas levels. The
patient was discharged to be observed in the pulmonary and cardiac
clinics. She later underwent polysomnography and a shunt study as an
outpatient. Polysomnography failed to show evidence of obstructive
sleep apnea or central apnea. A shunt study was performed by sampling
the patient’s arterial blood after having her breathe 100% oxygen for
20 min, and the results showed a shunt fraction of 11%. Surgery was
not offered as there was a concern that there was a prohibitive risk
and that the procedure would not enhance her pulmonary function.
|
Discussion
|
|---|
Clinical features of this case consist of a young woman with the
physical findings of a severe pectus excavatum deformity of her chest
wall and right-sided heart failure. Laboratory and other
investigational data indicate the presence of chronic hypercapnia,
hypoxemia with a significantly widened alveolar-arterial oxygen
gradient (22 mm Hg), an increased hemoglobin level, severe pulmonary
hypertension, and right atrial and right ventricular enlargement
without evidence for an intrinsic cardiac disease or an intracardiac
shunt. Lung fields were essentially clear except for some interstitial
changes in the left lower lobe seen on a high-resolution CT scan. Is
this a "zebra or a cobra on high heels," to paraphrase Dr. Eugene
Robins’ colorful description of the dilemma of separating an esoteric
case from the mundane? To answer this question, a systematic approach
considering all relevant diagnoses is essential.
The absence of a left ventricular disorder, valvular heart disease, or
an intracardiac shunt as a cause of severe pulmonary hypertension and
the presence of hypercapnia in this case would point to lung disease,
chest wall disorder, diaphragmatic dysfunction, neuromuscular disease,
obstructive apnea, or obesity-hypoventilation as possible causes of cor
pulmonale with secondary pulmonary hypertension. An intrinsic
(ie, diffuse infiltrative/interstitial) lung disease causing
chronic hypoxemia resulting in cor pulmonale can be excluded on the
basis of its absence on a chest radiograph and a CT scan of the chest.
A low TLC and a normal FEV1/FVC ratio exclude an
obstructive lung disease. Clinical features, polysomnography, and the
studies of diaphragmatic function exclude obesity-hypoventilation,
obstructive apnea, central apnea, neuromuscular disease, or
diaphragmatic dysfunction as possible causes of alveolar
hypoventilation. By process of elimination, chest wall deformity seems
the only logical cause of hypercapnic respiratory failure and cor
pulmonale in this case. Severe impairment of vital capacity (VC) [0.72
L; 19% of predicted] and TLC (1.76 L; 35% of predicted) are clearly
the consequences of the severe restraint imposed by pectus excavatum
deformity.
Profound gas exchange abnormalities, in this case, are the combined
results of venous admixture, ventilation/perfusion mismatch, and
alveolar hypoventilation. Evidence of a widened alveolar-arterial
oxygen gradient of 22 mm Hg and a shunt fraction of 11% suggest
significant contributions to hypoxemia from both ventilation-perfusion
mismatch and venous admixture. Hypercapnia, the result of alveolar
hypoventilation, is an additional contributing factor. Similar
mechanisms for gas exchange abnormalities are operative in patients
with other disorders of the chest wall, including kyphoscoliosis,
neuromuscular disease, or obesity-hypoventilation, as a consequence of
the compression of otherwise normal lung parenchyma. Compression of the
left lower lobe by the displaced heart alone could account for the
widened alveolar-arterial oxygen gradient in our patient.
The most significant abnormality in this case is a severe pectus
excavatum (funnel chest) deformity, with only 2 cm of space between the
vertebral bodies and the sternum, displacing the entire heart into the
left hemithorax. Severe impairment of VC and TLC with a normal
FEV1/FVC ratio and a near-normal, volume-adjusted
diffusing capacity of the lung (Table 1)
appear to be the consequences
of the displacement and compression of lung parenchyma by an extreme
degree of pectus excavatum, resulting in severe chronic hypercapnia,
hypoxemia, and cor pulmonale.
Pectus excavatum was first described by Bauhinus in 15961
and later exhaustively studied by Ebstein.5
Anatomic
changes of pectus excavatum and the approaches for its correction were
first described comprehensively by Brown.6
Pectus
excavatum is the result of a developmental abnormality of the anterior
portion of the diaphragm. Often familial in nature, the deformity
affects about 2.2% of the population. Clinical manifestations are
mainly cosmetic and orthopedic in nature, with frequent psychological
effects on children and their parents. Cardiac manifestations are said
to be limited mostly to auscultation findings in one half of the
patients and consist of a loud parasternal systolic murmur with a
thrill and a split second sound. ECG changes (Fig 1)
occur because of
the displacement of the heart toward the left. Subjective symptoms of
easy fatigability, exercise intolerance, dyspnea, precordial pain, and
palpitations have been attributed to cardiac displacement, rotation,
and angulation of great vessels. Congestive cardiac failure is almost
unheard of and has not been observed in a number of extensive
hemodynamic studies.2
3
4
In a few cases, right ventricular
pressure patterns showed a postsystolic dip with elevated end-diastolic
pressure much like that seen in patients with mild constrictive
pericarditis, which suggested disturbed right ventricular diastolic
filling as a result of compression, which has been demonstrated by
angiography in some cases.7
Similarly, the lung volume profile generally has been found to be
within the normal range except for an occasional slight increase in the
residual volume or mild reductions in TLC and VC.6
8
9
Pectus excavatum, unlike deformities of the spine, rarely causes
measurable functional impairment and has never resulted in
hypoventilation and respiratory failure.1
A comparison with other reported surgical series10
11
12
13
14
15
indicates that our patient has the most severe degree of pectus
excavatum deformity based on the criteria in Table 2
. An exhaustive review by Gaensler1
and our review of the
literature have failed to find a similar reported case. Therefore, we
believe that this is the first report of a case of severe pectus
excavatum causing chronic hypercapnic respiratory failure, pulmonary
hypertension, and chronic cor pulmonale.
Surgical repair of the deformity provides cosmetic benefits, but the
pathophysiologic benefits remain controversial. Although subjective
improvement in exercise tolerance and dyspnea often are noted after
surgery,12
13
pulmonary function improvement is infrequent
and modest.14
Conversely, others have shown a reduction in
pulmonary function after surgical repair.10
15
Moreover,
it should be noted that all reported surgical series consist of
patients with either normal or mildly impaired pulmonary function.
Consequently, the appropriateness of surgical repair is debatable when
a substantial improvement in lung function is the primary objective, as
it is in our patient.
|
Acknowledgements
|
|---|
The authors thank Jenifer S. Khan for her
assistance in editing the article.
|
Footnotes
|
|---|
Abbreviations: TLC = total lung capacity;
VC = vital capacity
Received for publication March 14, 2000.
Accepted for publication November 9, 2000.
|
References
|
|---|
-
Gaensler, EA (1965) Lung displacement. Fenn, WO Rahn, H eds. Handbook of physiology: respiration ,1649-1650 American Physiological Society Washington, DC.
-
Ravitch, MM (1951) Pectus excavatum and heart failure. Surgery 30,178-194[ISI][Medline]
-
Lyons, HA, Zuhdi, MN, Kelly, JJ, Jr (1955) Pectus excavatum, cause of impaired ventricular distensibility as exhibited by right ventricular pressure pattern. Am Heart J 50,921-922
-
Reusch, CS (1961) Hemodynamic studies in pectus excavatum. Circulation 24,1143-1150[Free Full Text]
-
Ebstein, W (1882) Uber die trichterbrust. Arch Klin Med 30,411-423
-
Brown, AL (1939) Pectus excavatum. J Thorac Surg 9,164-184
-
Fabricius, J, Davidson, HG, Hansen, AT (1957) Cardiac function in funnel chest. Dan Med Bull 4,251-257
-
Polgar, G, Koop, CE (1963) Pulmonary function in pectus excavatum. Pediatrics 32,209-215[Abstract/Free Full Text]
-
Weg, JG, Krumholz, RA, Harkleroad, LE (1967) Pulmonary dysfunction in pectus excavatum. Am Rev Respir Dis 96,936-945[ISI][Medline]
-
Kaguraoka, H, Ohnuki, T, Itaoka, T, et al (1992) Degree of severity of pectus excavatum and pulmonary function in pre-operative and post-operative periods. Thorac Cardiovasc Surg 104,1483-1488
-
Nakahara, K, Ohno, K, Miyoshi, S, et al (1987) An evaluation of operative outcome in patients with funnel chest diagnosed by means of the computed tomogram. Thorac Cardiovasc Surg 93,577-582
-
Haller, JA, Scherer, LR, Turner, CS, et al (1989) Evolving management of pectus excavatum based on a single institutional experience of 664 patients. Ann Surg 209,578-582[ISI][Medline]
-
Morshuis, W, Folgering, H, Barentsz, J, et al (1994) Pulmonary function before surgery for pectus excavatum and at long-term follow-up. Chest 105,1646-1652[Abstract/Free Full Text]
-
Cahill, JJ, Lees, GM, Robertson, HT (1984) A summary of pre-operative and post-operative cardiorespiratory performance in patients undergoing pectus excavatum and carnivatum repair. J Pediatr Surg 19,430-433[ISI][Medline]
-
Wynn, S, Driscol, D, Ostrom, N, et al (1990) Exercise cardiorespiratory function in adolescents with pectus excavatum. Thorac Cardiovasc Surg 99,41-47
This article has been cited by other articles:
|
|
|
|
 
P. Glassner, J. R. Bach, A. Mansour, J. S. Khan, and M. A. Khan
Pectus and Hypoventilation
Chest,
February 1, 2002;
121(2):
664 - 665.
[Full Text]
[PDF]
|
|
|
TOP
Abstract
Introduction
