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Absent left pulmonary artery, right-sided aortic arch and patent ductus arteriosus with right to left shunt
Absent Aortic
Left Pulmonary Arch
and Patent
with Right CLYDE WV,
Artery,
Right-Sided
Ductus
Arteriosus
to Left Shunt*
M.D., RAPHAEL BALCON, M.B., RAYMOND S. KURTZMAN, M.D. and VERNON E. WENDT, M.D., F.A.C.C. Detroit, Michigan
T
HE ABSENCEof the left pulmonary artery, right-sided aortic arch and patent ductus arteriosus with right to left shunt is a highly unusual combination of cardiovascular abnormalities. We recently studied a patient with this combination of anomalies. To our knowledge, only one other similar case has been reported, and in that patient there was a predominant left to right shunt through a patent ductus arteriosus.’ s2
Early digital clubbing was present. The veins of the optic fundi were markedly tortuous, but the arterioles and discs were normal. The jugular venous pressure and wave pattern were also normal. Arterial pulses were palpable, synchronous and of equal intensity. The blood pressure was 1 lo/70 mm. Hg in both arms. The pigeon shaped chest was significantly flattened on the left side. An upper dorsal scoliosis was present, with convexity to the right. The trachea was deviated to the left. Breath sounds were normal throughout, and the lungs were clear to percussion and auscultation. The maximal apical impulse was palpable in the sixth left intercostal space 12 cm. to the left of the mid-sternal line. There was no right ventricular heave. No thrills were palpable. A harsh precordial ejection systolic murmur was maximal in the fourth left intercostal space, 6 cm. to the left of the sternal border; there was no radiation of the murmur to the back or to the axilla. A soft blowing diastolic murmur was audible intermittently in the second left intercostal space parasternally. The laboratory data revealed that the average hemoglobin was 16.7 gm.yo; the average hematocrit 55%; white blood cells 9,9OO/cu.mm., with 67yc nucleated polymorpholeukocytes, 11 y0 lymphocytes, 4% monocytes and 18% eosinophils. However, the total eosinophil count was only 377/cu. mm., which is within normal limits. Urinalysis revealed 1 plus albumin, 2 to 3 white blood cells and occasional red blood cells per high-power field. Stool examination was negative for ova and parasites. The fasting blood sugar was 75 mg.% and the blood urea nitrogen was 8 mg./lOO ml. A sickle cell preparation and a Kline test both showed negative results. An electrocardiogram (Fig. 1) showed normal sinus rhythm and right ventricular hypertrophy, according to the criteria of Sokolow and Lyon.S The chest x-ray Jilrns (Fig. 2A, 2B) showed a severe
CASE REPORT The patient, a 22 year old, severely mentally retarded Negro man, was first seen at the Detroit Receiving Hospital on July 14, 1963, because of increasing exertional light-headedness of two weeks duration. He was known to have had a heart murmur at an early age, but a definite diagnosis had never been established. He always had exertional dyspnea and was never able to participate in competitive exercises. For one year before admission he had had light-headedness and increasing dyspnea on exertion, which would occur after climbing one flight of stairs. In addition, he noted frequent palpitations. There was no history of syncope, true vertigo, angina, pedal edema, paroxysmal nocturnal dyspnea nor orthopnea. He had a single episode of hemoptysis one year prior to admission. At 13 years of age he was said to have had “rheumatic fever,” but this was not documented. There was no significant family history. On physical examination the patient appeared younger than his stated age and was of small stature, 65 inches (165 cm.) tall, and weighed 97 pounds (44 kg.). He was severely retarded mentally. There was peripheral and central cyanosis, with no apparent difference between the upper and lower extremities.
* From the Departments of Medicine and Radiology, Wayne State University College of Medicine, Detroit, Mich. This work was supported by U. S. Public Health Service Grant H-5043, the American Heart Association, the Michigan Heart Association, Life Insurance Medical Research Fund, Tobacco Industry Research Committee, and the BurroughsWellcome Fund. 702
THE
AMERICAN
JOURNAL
OF
CARDIOLOGY
Absent Left Pulmonary
FIG. 1.
Electrocardiogram
Artery
703
taken Sept. 28, 1963, demonstrating significant right ventricular hypertrophy.
FIG. 2. Chest roentgenograms. A, PA view showing severe upper dorsal kyphoscoliosis, displacement of heart to left, and right aortic arch. The pulmonary artery is prominent, and there is also evidence of overcirculation of right lung, with decreased markings on the left. B, lateral view demonstrating portion of right upper lobe in the left thorax.
upper dorsal kyphoscoliosis, with convexity toward the right. The heart was displaced to the left. The aortic arch was on the right. The main pulmonary artery was prominent, and there was evidence of overcirculation of the right lung, with distinct diminution in the size and quantity of blood vessels On the lateral and other markings in the left lung. view (Fig. 2B) a portion of the right upper lobe was observed in the left thorax. There was no evidence of left atria1 enlargement or intracardiac calcification. VOLUME 14, NOVEMBER 1964
Bronchography (Fig. 3) showed a normal distribution of the bronchi on the left. There was an arcuate configuration of the bronchi of right upper lobe, further demonstrating that a portion of it had The remaining bronchi herniated into the left thorax. were normal. Cardiac catheterization was carried out with a No, 8 Birdseye catheter. A normal course was followed throughout the right side of the heart into the main pulmonary artery. The catheter then easily passed
704
M:u, Balcon, Kurtzman
and Wendt TABLE
I
Catheterization
Catheter Position
Oxygen Content (vol.%
11.5 11.5 11.2 11.1 14.5 14.5 14.5
PA RV RA svc Aorta (high) Aorta (mid) Aorta (low)
Data
0 xygen Saturation
Pressure (mm.
cc”01
60 60 59.5 59 75 75 75
W
116/70 116/O 8/O l&/80 116/80
...
PA = pulmonary artery; RV = right ventricle; RA = right atrium; SVC = superior vena cava.
FIG. 3. Bronchogram (PA view) showing normal distribution of bronchi. Again, a portion of right upper lobe is seen in the left thorax. into the descending aorta (Fig. 4j. ‘The catheter data are shown in Table I. It may be seen that there is no gradient across the pulmonary valve and that the pressures in the right ventricle and aorta were equal. There was a 3 vol.‘% increment of oxygen
content between the aorta and the pulmonary artery and a moderate degree of peripheral oxygen desaturaIt may be noted that the oxygen content tion (75%). of the samples taken in the high, middle and low aortic positions were identical, indicating that the origin of the ductus is probably proximal to the high Thus, the usual differential of oxygen aortic position. content between samples from the upper and lower extremities found in patients with patent ductus arteriosus with right to left shunt was not present in this patient. Pulmonary angiocardiography demonstrated the ab-
FIG. 5. Pulmonary angiogram showing absence of the left pulmonary artery. Note dilated main pulmonary artery and overcirculation of the lung. The venous catheter (V) is in the main pulmonary artery, whereas the arterial catheter (A) is in the descending aorta. THE
AMERICAN
JOURNAL
OF CARD101 .OGY
Absent
Left Pulmonary
$I;.- 6
Artery
F;G. 7
The Roman numerals, I to VI, designate the Normal embryologic development of aortic arches (see text). paired aortic arches. The dotted lines indicate those arches and segments which in the human being are normally absorbed; the darkened areas indicate those arches and segments which function in the postnatal state. RCCA = right common carotid artery, LCCA = left common carotid artery, IA = innominate artery, DA = ductus arteriosus, RPA = right pulmonary artery, LPA = left pulmonary artery and desc. aorta = descending aorta. FIG. 7. Abnormal embryologic development of the aortic arches postulated in the patient described (see text). For abbreviations, see Figure 6. FIG. 6.
sence of the left pulmonary artery (Fig. 5). The main pulmonary artery was dilated, and there was overcirculation of the right lung. Cineangiocasdiography was performed following the injection of contrast into the ascending aorta and revealed a right-sided aorta and a structure compatible with a patent ductus arteriosus. A large bronchial artery originating from the left side of the ascending aorta was also demonstrated. Pulmonary function studies were performed in the laboratory of Dr. Benjamin Lewis. However, because of the patient’s inability to cooperate, the only valid finding was that of a normal residual volume. DISCUSSION
Complete absence of a main branch of the pulmonary artery is a rare congenital abnormalIn a recent review of the world’s literature, ity. Pool and co-workers’ reported only 102 patients
with this anomaly. These investigators emphasized the difficulties in nomenclature and were of the opinion that terms such as agenesis, hypoplasia and aplasia should not be used interchangeably. They concluded that the term “absence” should indicate complete absence of a main branch of the pulmonary artery, whereas the term “hypoplasia” should indicate those instances in which a remnant artery branch is present. VOLUME 14, NOVEMBER 1964
of a pulmonary
Equal numbers of an absent left or right pulmonary artery have been found by most investigators, although there is a higher incidence in female patients.’ s4+ Absence of the right pulmonary artery is more likely to be an isolated defect ; this was found in 15 of the 26 patients reported by Sherrick and co-workers6 and in 18 of the 38 patients described by Pool and his assoOn the other hand, isolated absence of ciates.l the left pulmonary artery occurred in only 5 of 26 and 14 of 40 patients in the same series.‘s5 The defect most commonly associated with an absent left pulmonary artery is tetralogy of Fallot.1~5~7 Other anomalies occurring with an absent left or right pulmonary artery have included ventricular septal defect, atria1 septal defect, patent ductus arteriosus, coarctation of the aorta and aortic-pulmonary window defect. The association of patent ductus arteriosus with In a right-sided aortic arch is also uncommon. a comprehensive review of thoracic arterial arch anomalies, Blake and Manion* were able to find only 5 patients with this condition. Absence of the left pulmonary artery, rightsided aortic arch and patent ductus arteriosus is To our knowledge, only 1 pavery infrequent. tient with this combination of anomalies has been described previously.1*2 In this patient a
706
\Vu, Balccm,
Kurtxman
predominant left to right shunt was encountered, and surgery was successfully performed. In OU! patient, however, in addition to the anomalies previously described, there was significant pulmonary hypertension and a right to left shunt through the patent ductus arteriosus. Therefore, surgery was not advised. In an attempt to elucidate this Embryology: unusual abnormality, a brief review of the embryology of the aortic arches was undertaken. In the normal development (Fig. 6) the first and second aortic arches are usually present by the twenty-third day, the third and fourth aortic arches by the thirty-first day and the sixth aortic arches by the thirty-sixth day of gestation.g The third arches persist to form the carotid arteries, while the first and second arches eventually disappear. The right fourth aortic arch becomes the innominate artery, while the left fourth aortic arch becomes the adult aorta to the level of the ductus. The fifth aortic arch is usually not present in man. The sixth aortic arches become the main and left pulmonary According to Bremer,*O the right pularteries. monary artery appears to be a branch of the combined main and left pulmonary artery precursors. By 50 days of gestation, a prototype of the adult cardiovascular anatomy is usually fully developed. s The embryology of the pulmonary arteries in man and mammals has been thoroughly investigated by Bremer,iO Huntington” and Congdon.i2 These investigators found that unlike the other aortic arches formed by the union of ventral and dorsal arch buds, the pulmonary arches also received contributions from vessels of the primary lung buds. These buds, derived from the esophagus, carry with them a portion of the splanchnic plexus, the so-called “postbranchial Huntington further plexus” of Huntington.” demonstrated vascular connections from the dorsal aorta below the sixth aortic arch which communicated with the postbranchial plexus. These vessels are thought to be early precursors of the bronchial arteries.” The sixth dorsal bud originates from the dorsal aorta, while the ventral bud stems from the aortic sac.10s12 The ventral and dorsal buds of the sixth aortic arches and tributaries of the postbranchial plexus unite to form the pulmonary artery, and a portion of the dorsal bud on the left becomes the ductus arteriosus (Fig. 6). The right dorsal bud usually does not persist, thus making a right-sided ductus arteriosus a very infrequent congenital anomaly.10-12
and Wendt
Patlqpe.k of li’nilateral Absence of Pulmonary .drtery: Many theories have been advanced to explain both the unilateral absence of the pulmonary artery and the origin of the blood supply to the affected lung. Some investigators have suggested that an absent right pulmonary artery may be due to incomplete rotation of the pulmonary arteries about the truncus arteriosus.i3Bi4 Thus, when the aortic-pulmonary septum develops, the right pulmonary artery would be enveloped in the aortic portion. Another group of investigators explain the absence of the left pulmonary artery, associated with tetralogy of Fallot, on the basis of a defect in the formation of the bulbus cordis.’ This hypothesis is based on the work of Bremer,‘O who found that the left pulmonary artery is closely related to the development of the main pulmonary artery. Therefore, the absence of the left pulmonary artery and tetralogy of Fallot could occur together relatively often. However, Barthel16 and Tabakin and co-workers” have described the absence of the left pulmonary artery with no associated defects, and thus the apparent cause and effect relationship of these theories does not apply in all instances. In the 102 cases of unilateral absence of the pulmonary artery reviewed by Pool and coworkers,’ patent ductus arteriosus was usually associated with an absent right, rather than left, pulmonary artery. In normal development the right dorsal portion of the pulmonary arch is absorbed, and thus a right-sided ductus is usually not present even with an absent left pulmonary artery. Furthermore, when the right pulmonary artery is absent, a patent ductus is not usually present on the left, as the ventral portion of the pulmonary arch to which the ductus is normally joined is also absent.’ In our patient the absence of the left pulmonary artery and the presence of patent ductus arteriosus and rightsided aortic arch appear to represent persistence of the right ductal part of the pulmonary arch and of the fourth right aortic arch and the absorption of the left fourth and sixth aortic arches (Fig. 7). Pulmonary hypertension has frequently been associated with unilateral absence of the main branch of the pulmonary artery. In Pool’s series the incidence was 19 per cent in those patients with isolated lesions and increased remarkably when this anomaly was associated with patent ductus arteriosus.’ In the 11 patients with patent ductus arteriosus and unilateral absence of the pulmonary artery, all were THE
AMERICAN
JOURNAL
OF CARDIOLOGY
Absent
Left
Pulmonary
found to have consistently elevated pulmonary artery pressures.’ Pool and colleagues hypothesized that an increased pulmonary blood flow from the time of birth was an important factor in the development of pulmonary hypertension. Significant pulmonary hypertension was also observed in our patient. Pulmonary function studies in patients with unilateral absence of the pulmonary artery have been reported by several investigators.‘J7-lg These have included measurements of vital capacity, maximal breathing capacity, residual volume and total lung volume, all of which have been within the normal range. Unfortunately, in our patient, pulmonary function studies were not satisfactory due to the patient’s low intelligence level and inability to cooperate. However, normal residual volume was present, and this certainly agrees with the results of studies done by other investigators.1J7-1g In a few patients in whom bronchospirometric studies have been made, the oxygen uptake of the affected lung was found negligible, but a significant increase was detected in the expired carbon dioxide from the affected lung.’ Bronchoscopy and bronchograms performed in these patients generally demonstrated normal bronchial structure, although crowding and irregular constrictions of the affected side have been reIn our patient the bronported on occasion.’ chogram was within normal limits. Significant bronchial blood flow to the affected lung has been demonstrated by several investigators.‘J7 This was also true of Pool’s patient, whose defects were similar to those found in our patient. Right to left shunt through a patent ductus arteriosus in adults was recently reviewed by Dailey and co-workers,20 who found only 47 patients in the world literature with this condition. It is interesting to note that only 3 of these patients were ever known to have had a continuous murmur. Our patient also did not have the typical murmur of a patent ductus arteriosus.
SUMt4ARY A patient is reported with an absent left pulmonary artery, right-sided aortic arch, patent ductus arteriosus and right to left shunt. A brief review of the embryology of the aortic arches is presented, and a possible embryologic basis for this condition is postulated. An extensive review of the literature reveals only 1 similar case with this unusual combination of cardiovascular anomalies, and in that patient a predominant left to right shunt was present. VOLUME
14, NOVEMBER 1964
Artery
707 ACKNOWLEDGMENTS
The authors wish to acknowledge the helpful comments and suggestions of Richard J. Bing, M.D., Professor and Chairman of the Department of Medicine, Wavne State University College of Medicine. In addition, we wish to thank Samuel Boushy, M.D., who performed the pulmonary function studies of this patient. REFERENCES 1. POOL, P. E., VOGEL, J. H. K. and BLOUNT, S. G. Congenital unilateral absence of a pulmonary artery. Am. J. Cardial., 10: 706, 1962. 2. SWAN, H., OWENS, J. C., POOL, P. E., VOGEL, J. H. K. and BLOUNT, S. G. Absent left pulmonary artery and right sided patent ductus arteriosus. A.M.A. Arch. Surg., 87: 196, 1963. 3. SOKOLOW, M. and LYON, T. P. The ventricular complex in right ventricular hypertrophy as obtained by unipolar precordial and limb leads. Am. Heart J., 38: 273, 1949. 4. STEINBERG,I. Congenital absence of a main branch of a pulmonary artery. A report of 3 new cases associated with bronchiectasis, atria1 septal defect and with Eisenmenger’s complex. Am. J. Med., 24: 559, 1958. 5. SHERRICK, D. W., KINCAID, 0. W. and DUSHANE, J. W. Agenesis of a main branch of a pulmonary artery. Am. J. Roentgenol., 87: 917, 1962. 6. OAKLEY, C., GLICK, G. and MCCOEDIE, R. M. Congenital absence of a pulmonary artery. Am. J. Med., 34: 264, 1963. 7. SMART, J. and PA?TINSON, J. N. Congenital absence of the left pulmonary artery. Brit. Heart J., 1: 491, 1956. 8. BLAKE, H. A. and MANION, W. C. Thoracic arterial arch anomalies. Circulation, 26: 251, 1962. 9. HEINTZEN, P. and TESKE, I. Die einseitige Agenesie der Lungenarterie. Arch. Kreislaufforsch., 32: 263, 1960. 10. BREMER, J. L. On the origin of the pulmonary arteries in mammals. Am. J. Anat., 1: 137, 1902. 11. HUNTINGTON,G. S. The morphology of the pulmonary artery in the mammals. Anat. Rec., 17: 165, 1919. 12. CONGDON,E. D. Transformation of the aortic arch system during the development of the human Carnegie Inst. Contrib. Embryol., 14: 47, embryo. 1922. 13. CARO, C., LERMANDA, V. C. and LYONS, H. A. Aortic origin of the right pulmonary artery. Brit. Heart J., 19: 345, 1957. 14. SCHNEIDERMAN,L. J. Isolated congenital absence of the right pulmonary artery: A caution as to its diagnosis and a proposal for its embryogenesis. Report of a case with review. Am. Heart J., 55: 772, 1958. 15. EMANUEL, R. W. and PATTINSON,J. N. Absence of the left pulmonary artery in Fallot’s tetralogy. Brit. Heart J., 18: 289, 1956. 16. BARTHEL, H. Aplasie einer Lungenarterie. Thoraxchir., 4: 287, 1956. 17. TABAKIN, B. S., HANSON, J. S., ADHIKARI, P. K. and MILLER, D. B. Physiologic studies in congenital absence of the left main pulmonary artery. Circulation, 22: 1107, 1960. 18. FISHER, J. M. and VAN EPPS, E. F. Aplasia or
708
Wu, Balcon,
Kurtzman
hypoplasia of one pulmonary artery: Radiologic and pulmonary function studies. Am. Heart .I., 58: 26, 1959. 19. LANDINGAN, P. L., PURKIS, I. E., ROY, D. E. and CIJDKOWICZ, L. Cardiorespiratory studies in a
and Wendt
patient with absent left pulmonary artery. Thorax, 18: 77, 1963. 20. DAILEY, F. H., GENOVESE, P. D. and BEHARKE, R. H. Patent ductus arteriosus with reversal of flow in adults. Ann. Znt. Med., 56: 865, 1962.
THE AMERICAN JOURNAL OF CARDIOLOGY
Left Pulmonary Arch
and Patent
with Right CLYDE WV,
Artery,
Right-Sided
Ductus
Arteriosus
to Left Shunt*
M.D., RAPHAEL BALCON, M.B., RAYMOND S. KURTZMAN, M.D. and VERNON E. WENDT, M.D., F.A.C.C. Detroit, Michigan
T
HE ABSENCEof the left pulmonary artery, right-sided aortic arch and patent ductus arteriosus with right to left shunt is a highly unusual combination of cardiovascular abnormalities. We recently studied a patient with this combination of anomalies. To our knowledge, only one other similar case has been reported, and in that patient there was a predominant left to right shunt through a patent ductus arteriosus.’ s2
Early digital clubbing was present. The veins of the optic fundi were markedly tortuous, but the arterioles and discs were normal. The jugular venous pressure and wave pattern were also normal. Arterial pulses were palpable, synchronous and of equal intensity. The blood pressure was 1 lo/70 mm. Hg in both arms. The pigeon shaped chest was significantly flattened on the left side. An upper dorsal scoliosis was present, with convexity to the right. The trachea was deviated to the left. Breath sounds were normal throughout, and the lungs were clear to percussion and auscultation. The maximal apical impulse was palpable in the sixth left intercostal space 12 cm. to the left of the mid-sternal line. There was no right ventricular heave. No thrills were palpable. A harsh precordial ejection systolic murmur was maximal in the fourth left intercostal space, 6 cm. to the left of the sternal border; there was no radiation of the murmur to the back or to the axilla. A soft blowing diastolic murmur was audible intermittently in the second left intercostal space parasternally. The laboratory data revealed that the average hemoglobin was 16.7 gm.yo; the average hematocrit 55%; white blood cells 9,9OO/cu.mm., with 67yc nucleated polymorpholeukocytes, 11 y0 lymphocytes, 4% monocytes and 18% eosinophils. However, the total eosinophil count was only 377/cu. mm., which is within normal limits. Urinalysis revealed 1 plus albumin, 2 to 3 white blood cells and occasional red blood cells per high-power field. Stool examination was negative for ova and parasites. The fasting blood sugar was 75 mg.% and the blood urea nitrogen was 8 mg./lOO ml. A sickle cell preparation and a Kline test both showed negative results. An electrocardiogram (Fig. 1) showed normal sinus rhythm and right ventricular hypertrophy, according to the criteria of Sokolow and Lyon.S The chest x-ray Jilrns (Fig. 2A, 2B) showed a severe
CASE REPORT The patient, a 22 year old, severely mentally retarded Negro man, was first seen at the Detroit Receiving Hospital on July 14, 1963, because of increasing exertional light-headedness of two weeks duration. He was known to have had a heart murmur at an early age, but a definite diagnosis had never been established. He always had exertional dyspnea and was never able to participate in competitive exercises. For one year before admission he had had light-headedness and increasing dyspnea on exertion, which would occur after climbing one flight of stairs. In addition, he noted frequent palpitations. There was no history of syncope, true vertigo, angina, pedal edema, paroxysmal nocturnal dyspnea nor orthopnea. He had a single episode of hemoptysis one year prior to admission. At 13 years of age he was said to have had “rheumatic fever,” but this was not documented. There was no significant family history. On physical examination the patient appeared younger than his stated age and was of small stature, 65 inches (165 cm.) tall, and weighed 97 pounds (44 kg.). He was severely retarded mentally. There was peripheral and central cyanosis, with no apparent difference between the upper and lower extremities.
* From the Departments of Medicine and Radiology, Wayne State University College of Medicine, Detroit, Mich. This work was supported by U. S. Public Health Service Grant H-5043, the American Heart Association, the Michigan Heart Association, Life Insurance Medical Research Fund, Tobacco Industry Research Committee, and the BurroughsWellcome Fund. 702
THE
AMERICAN
JOURNAL
OF
CARDIOLOGY
Absent Left Pulmonary
FIG. 1.
Electrocardiogram
Artery
703
taken Sept. 28, 1963, demonstrating significant right ventricular hypertrophy.
FIG. 2. Chest roentgenograms. A, PA view showing severe upper dorsal kyphoscoliosis, displacement of heart to left, and right aortic arch. The pulmonary artery is prominent, and there is also evidence of overcirculation of right lung, with decreased markings on the left. B, lateral view demonstrating portion of right upper lobe in the left thorax.
upper dorsal kyphoscoliosis, with convexity toward the right. The heart was displaced to the left. The aortic arch was on the right. The main pulmonary artery was prominent, and there was evidence of overcirculation of the right lung, with distinct diminution in the size and quantity of blood vessels On the lateral and other markings in the left lung. view (Fig. 2B) a portion of the right upper lobe was observed in the left thorax. There was no evidence of left atria1 enlargement or intracardiac calcification. VOLUME 14, NOVEMBER 1964
Bronchography (Fig. 3) showed a normal distribution of the bronchi on the left. There was an arcuate configuration of the bronchi of right upper lobe, further demonstrating that a portion of it had The remaining bronchi herniated into the left thorax. were normal. Cardiac catheterization was carried out with a No, 8 Birdseye catheter. A normal course was followed throughout the right side of the heart into the main pulmonary artery. The catheter then easily passed
704
M:u, Balcon, Kurtzman
and Wendt TABLE
I
Catheterization
Catheter Position
Oxygen Content (vol.%
11.5 11.5 11.2 11.1 14.5 14.5 14.5
PA RV RA svc Aorta (high) Aorta (mid) Aorta (low)
Data
0 xygen Saturation
Pressure (mm.
cc”01
60 60 59.5 59 75 75 75
W
116/70 116/O 8/O l&/80 116/80
...
PA = pulmonary artery; RV = right ventricle; RA = right atrium; SVC = superior vena cava.
FIG. 3. Bronchogram (PA view) showing normal distribution of bronchi. Again, a portion of right upper lobe is seen in the left thorax. into the descending aorta (Fig. 4j. ‘The catheter data are shown in Table I. It may be seen that there is no gradient across the pulmonary valve and that the pressures in the right ventricle and aorta were equal. There was a 3 vol.‘% increment of oxygen
content between the aorta and the pulmonary artery and a moderate degree of peripheral oxygen desaturaIt may be noted that the oxygen content tion (75%). of the samples taken in the high, middle and low aortic positions were identical, indicating that the origin of the ductus is probably proximal to the high Thus, the usual differential of oxygen aortic position. content between samples from the upper and lower extremities found in patients with patent ductus arteriosus with right to left shunt was not present in this patient. Pulmonary angiocardiography demonstrated the ab-
FIG. 5. Pulmonary angiogram showing absence of the left pulmonary artery. Note dilated main pulmonary artery and overcirculation of the lung. The venous catheter (V) is in the main pulmonary artery, whereas the arterial catheter (A) is in the descending aorta. THE
AMERICAN
JOURNAL
OF CARD101 .OGY
Absent
Left Pulmonary
$I;.- 6
Artery
F;G. 7
The Roman numerals, I to VI, designate the Normal embryologic development of aortic arches (see text). paired aortic arches. The dotted lines indicate those arches and segments which in the human being are normally absorbed; the darkened areas indicate those arches and segments which function in the postnatal state. RCCA = right common carotid artery, LCCA = left common carotid artery, IA = innominate artery, DA = ductus arteriosus, RPA = right pulmonary artery, LPA = left pulmonary artery and desc. aorta = descending aorta. FIG. 7. Abnormal embryologic development of the aortic arches postulated in the patient described (see text). For abbreviations, see Figure 6. FIG. 6.
sence of the left pulmonary artery (Fig. 5). The main pulmonary artery was dilated, and there was overcirculation of the right lung. Cineangiocasdiography was performed following the injection of contrast into the ascending aorta and revealed a right-sided aorta and a structure compatible with a patent ductus arteriosus. A large bronchial artery originating from the left side of the ascending aorta was also demonstrated. Pulmonary function studies were performed in the laboratory of Dr. Benjamin Lewis. However, because of the patient’s inability to cooperate, the only valid finding was that of a normal residual volume. DISCUSSION
Complete absence of a main branch of the pulmonary artery is a rare congenital abnormalIn a recent review of the world’s literature, ity. Pool and co-workers’ reported only 102 patients
with this anomaly. These investigators emphasized the difficulties in nomenclature and were of the opinion that terms such as agenesis, hypoplasia and aplasia should not be used interchangeably. They concluded that the term “absence” should indicate complete absence of a main branch of the pulmonary artery, whereas the term “hypoplasia” should indicate those instances in which a remnant artery branch is present. VOLUME 14, NOVEMBER 1964
of a pulmonary
Equal numbers of an absent left or right pulmonary artery have been found by most investigators, although there is a higher incidence in female patients.’ s4+ Absence of the right pulmonary artery is more likely to be an isolated defect ; this was found in 15 of the 26 patients reported by Sherrick and co-workers6 and in 18 of the 38 patients described by Pool and his assoOn the other hand, isolated absence of ciates.l the left pulmonary artery occurred in only 5 of 26 and 14 of 40 patients in the same series.‘s5 The defect most commonly associated with an absent left pulmonary artery is tetralogy of Fallot.1~5~7 Other anomalies occurring with an absent left or right pulmonary artery have included ventricular septal defect, atria1 septal defect, patent ductus arteriosus, coarctation of the aorta and aortic-pulmonary window defect. The association of patent ductus arteriosus with In a right-sided aortic arch is also uncommon. a comprehensive review of thoracic arterial arch anomalies, Blake and Manion* were able to find only 5 patients with this condition. Absence of the left pulmonary artery, rightsided aortic arch and patent ductus arteriosus is To our knowledge, only 1 pavery infrequent. tient with this combination of anomalies has been described previously.1*2 In this patient a
706
\Vu, Balccm,
Kurtxman
predominant left to right shunt was encountered, and surgery was successfully performed. In OU! patient, however, in addition to the anomalies previously described, there was significant pulmonary hypertension and a right to left shunt through the patent ductus arteriosus. Therefore, surgery was not advised. In an attempt to elucidate this Embryology: unusual abnormality, a brief review of the embryology of the aortic arches was undertaken. In the normal development (Fig. 6) the first and second aortic arches are usually present by the twenty-third day, the third and fourth aortic arches by the thirty-first day and the sixth aortic arches by the thirty-sixth day of gestation.g The third arches persist to form the carotid arteries, while the first and second arches eventually disappear. The right fourth aortic arch becomes the innominate artery, while the left fourth aortic arch becomes the adult aorta to the level of the ductus. The fifth aortic arch is usually not present in man. The sixth aortic arches become the main and left pulmonary According to Bremer,*O the right pularteries. monary artery appears to be a branch of the combined main and left pulmonary artery precursors. By 50 days of gestation, a prototype of the adult cardiovascular anatomy is usually fully developed. s The embryology of the pulmonary arteries in man and mammals has been thoroughly investigated by Bremer,iO Huntington” and Congdon.i2 These investigators found that unlike the other aortic arches formed by the union of ventral and dorsal arch buds, the pulmonary arches also received contributions from vessels of the primary lung buds. These buds, derived from the esophagus, carry with them a portion of the splanchnic plexus, the so-called “postbranchial Huntington further plexus” of Huntington.” demonstrated vascular connections from the dorsal aorta below the sixth aortic arch which communicated with the postbranchial plexus. These vessels are thought to be early precursors of the bronchial arteries.” The sixth dorsal bud originates from the dorsal aorta, while the ventral bud stems from the aortic sac.10s12 The ventral and dorsal buds of the sixth aortic arches and tributaries of the postbranchial plexus unite to form the pulmonary artery, and a portion of the dorsal bud on the left becomes the ductus arteriosus (Fig. 6). The right dorsal bud usually does not persist, thus making a right-sided ductus arteriosus a very infrequent congenital anomaly.10-12
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Patlqpe.k of li’nilateral Absence of Pulmonary .drtery: Many theories have been advanced to explain both the unilateral absence of the pulmonary artery and the origin of the blood supply to the affected lung. Some investigators have suggested that an absent right pulmonary artery may be due to incomplete rotation of the pulmonary arteries about the truncus arteriosus.i3Bi4 Thus, when the aortic-pulmonary septum develops, the right pulmonary artery would be enveloped in the aortic portion. Another group of investigators explain the absence of the left pulmonary artery, associated with tetralogy of Fallot, on the basis of a defect in the formation of the bulbus cordis.’ This hypothesis is based on the work of Bremer,‘O who found that the left pulmonary artery is closely related to the development of the main pulmonary artery. Therefore, the absence of the left pulmonary artery and tetralogy of Fallot could occur together relatively often. However, Barthel16 and Tabakin and co-workers” have described the absence of the left pulmonary artery with no associated defects, and thus the apparent cause and effect relationship of these theories does not apply in all instances. In the 102 cases of unilateral absence of the pulmonary artery reviewed by Pool and coworkers,’ patent ductus arteriosus was usually associated with an absent right, rather than left, pulmonary artery. In normal development the right dorsal portion of the pulmonary arch is absorbed, and thus a right-sided ductus is usually not present even with an absent left pulmonary artery. Furthermore, when the right pulmonary artery is absent, a patent ductus is not usually present on the left, as the ventral portion of the pulmonary arch to which the ductus is normally joined is also absent.’ In our patient the absence of the left pulmonary artery and the presence of patent ductus arteriosus and rightsided aortic arch appear to represent persistence of the right ductal part of the pulmonary arch and of the fourth right aortic arch and the absorption of the left fourth and sixth aortic arches (Fig. 7). Pulmonary hypertension has frequently been associated with unilateral absence of the main branch of the pulmonary artery. In Pool’s series the incidence was 19 per cent in those patients with isolated lesions and increased remarkably when this anomaly was associated with patent ductus arteriosus.’ In the 11 patients with patent ductus arteriosus and unilateral absence of the pulmonary artery, all were THE
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Absent
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found to have consistently elevated pulmonary artery pressures.’ Pool and colleagues hypothesized that an increased pulmonary blood flow from the time of birth was an important factor in the development of pulmonary hypertension. Significant pulmonary hypertension was also observed in our patient. Pulmonary function studies in patients with unilateral absence of the pulmonary artery have been reported by several investigators.‘J7-lg These have included measurements of vital capacity, maximal breathing capacity, residual volume and total lung volume, all of which have been within the normal range. Unfortunately, in our patient, pulmonary function studies were not satisfactory due to the patient’s low intelligence level and inability to cooperate. However, normal residual volume was present, and this certainly agrees with the results of studies done by other investigators.1J7-1g In a few patients in whom bronchospirometric studies have been made, the oxygen uptake of the affected lung was found negligible, but a significant increase was detected in the expired carbon dioxide from the affected lung.’ Bronchoscopy and bronchograms performed in these patients generally demonstrated normal bronchial structure, although crowding and irregular constrictions of the affected side have been reIn our patient the bronported on occasion.’ chogram was within normal limits. Significant bronchial blood flow to the affected lung has been demonstrated by several investigators.‘J7 This was also true of Pool’s patient, whose defects were similar to those found in our patient. Right to left shunt through a patent ductus arteriosus in adults was recently reviewed by Dailey and co-workers,20 who found only 47 patients in the world literature with this condition. It is interesting to note that only 3 of these patients were ever known to have had a continuous murmur. Our patient also did not have the typical murmur of a patent ductus arteriosus.
SUMt4ARY A patient is reported with an absent left pulmonary artery, right-sided aortic arch, patent ductus arteriosus and right to left shunt. A brief review of the embryology of the aortic arches is presented, and a possible embryologic basis for this condition is postulated. An extensive review of the literature reveals only 1 similar case with this unusual combination of cardiovascular anomalies, and in that patient a predominant left to right shunt was present. VOLUME
14, NOVEMBER 1964
Artery
707 ACKNOWLEDGMENTS
The authors wish to acknowledge the helpful comments and suggestions of Richard J. Bing, M.D., Professor and Chairman of the Department of Medicine, Wavne State University College of Medicine. In addition, we wish to thank Samuel Boushy, M.D., who performed the pulmonary function studies of this patient. REFERENCES 1. POOL, P. E., VOGEL, J. H. K. and BLOUNT, S. G. Congenital unilateral absence of a pulmonary artery. Am. J. Cardial., 10: 706, 1962. 2. SWAN, H., OWENS, J. C., POOL, P. E., VOGEL, J. H. K. and BLOUNT, S. G. Absent left pulmonary artery and right sided patent ductus arteriosus. A.M.A. Arch. Surg., 87: 196, 1963. 3. SOKOLOW, M. and LYON, T. P. The ventricular complex in right ventricular hypertrophy as obtained by unipolar precordial and limb leads. Am. Heart J., 38: 273, 1949. 4. STEINBERG,I. Congenital absence of a main branch of a pulmonary artery. A report of 3 new cases associated with bronchiectasis, atria1 septal defect and with Eisenmenger’s complex. Am. J. Med., 24: 559, 1958. 5. SHERRICK, D. W., KINCAID, 0. W. and DUSHANE, J. W. Agenesis of a main branch of a pulmonary artery. Am. J. Roentgenol., 87: 917, 1962. 6. OAKLEY, C., GLICK, G. and MCCOEDIE, R. M. Congenital absence of a pulmonary artery. Am. J. Med., 34: 264, 1963. 7. SMART, J. and PA?TINSON, J. N. Congenital absence of the left pulmonary artery. Brit. Heart J., 1: 491, 1956. 8. BLAKE, H. A. and MANION, W. C. Thoracic arterial arch anomalies. Circulation, 26: 251, 1962. 9. HEINTZEN, P. and TESKE, I. Die einseitige Agenesie der Lungenarterie. Arch. Kreislaufforsch., 32: 263, 1960. 10. BREMER, J. L. On the origin of the pulmonary arteries in mammals. Am. J. Anat., 1: 137, 1902. 11. HUNTINGTON,G. S. The morphology of the pulmonary artery in the mammals. Anat. Rec., 17: 165, 1919. 12. CONGDON,E. D. Transformation of the aortic arch system during the development of the human Carnegie Inst. Contrib. Embryol., 14: 47, embryo. 1922. 13. CARO, C., LERMANDA, V. C. and LYONS, H. A. Aortic origin of the right pulmonary artery. Brit. Heart J., 19: 345, 1957. 14. SCHNEIDERMAN,L. J. Isolated congenital absence of the right pulmonary artery: A caution as to its diagnosis and a proposal for its embryogenesis. Report of a case with review. Am. Heart J., 55: 772, 1958. 15. EMANUEL, R. W. and PATTINSON,J. N. Absence of the left pulmonary artery in Fallot’s tetralogy. Brit. Heart J., 18: 289, 1956. 16. BARTHEL, H. Aplasie einer Lungenarterie. Thoraxchir., 4: 287, 1956. 17. TABAKIN, B. S., HANSON, J. S., ADHIKARI, P. K. and MILLER, D. B. Physiologic studies in congenital absence of the left main pulmonary artery. Circulation, 22: 1107, 1960. 18. FISHER, J. M. and VAN EPPS, E. F. Aplasia or
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hypoplasia of one pulmonary artery: Radiologic and pulmonary function studies. Am. Heart .I., 58: 26, 1959. 19. LANDINGAN, P. L., PURKIS, I. E., ROY, D. E. and CIJDKOWICZ, L. Cardiorespiratory studies in a
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patient with absent left pulmonary artery. Thorax, 18: 77, 1963. 20. DAILEY, F. H., GENOVESE, P. D. and BEHARKE, R. H. Patent ductus arteriosus with reversal of flow in adults. Ann. Znt. Med., 56: 865, 1962.
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