(Circulation. 1998;98:188-189.)
© 1998 American Heart Association, Inc.
Diagnostic Issues and Indications for Surgery in Patients With Pulmonary Artery Sling
Carl L. Backer, MD
Children's Memorial Hospital Chicago, Ill
To the Editor:
This letter is in reference to the brief article entitled "Combined
Pulmonary Artery Angiography and Tracheobronchography in
Pulmonary Artery Sling," authored by Joachim Freihorst and
Thomas Paul (Circulation. 1997;96:2079). The authors
reported their evaluation of a 12-month-old child with inspiratory and
expiratory stridor. Barium swallow showed an anterior impression of the
esophagus (consistent with a pulmonary artery sling).
Two-dimensional echocardiogram could not visualize the origin of the
left pulmonary artery. The authors proceeded to do combined
pulmonary angiography and tracheobronchography to diagnose the
pulmonary artery sling. The figure showing the combined
contrast injection in the pulmonary artery and lower trachea is
a nice demonstration of pulmonary artery sling, but in my
experience, these are 2 unnecessary studies. In our recent experience,
the diagnosis of pulmonary artery sling has been possible in
all cases with a comprehensive echocardiographic
analysis.1 We reviewed 19 cases of
pulmonary artery sling operated on over a 26-year period
(1970–1996). Pulmonary arteriography demonstrated the
pulmonary artery sling in 7 of 10 patients (70%). This
procedure has not been performed at our institution since 1991.
Two-dimensional color Doppler echocardiogram using
suprasternal/high-parasternal sweeps diagnosed pulmonary artery
slings in 7 of 7 patients (100%). Color Doppler demonstrated the
site of take-off, course, and relative size of the left
pulmonary artery as it arose from the right pulmonary
artery. Tracheobronchography was not performed on the patients, but
rather preoperative or intraoperative bronchoscopy was performed in all
cases to rule out associated complete tracheal rings, which were
present in 11 (58%) of the 19 patients. We concluded that in
preparation for surgery, the diagnosis of pulmonary artery
sling may be confidently made from echocardiography
alone. Angiography is no longer indicated to diagnose pulmonary
artery sling.
In addition, according to the article, this patient has not yet had
surgical intervention, but "is doing well on physical therapy and
close clinical follow-up." Our recommendation has been that all
children with respiratory symptoms and a pulmonary artery sling
should have such malformations repaired at the time of diagnosis. This
particular child has both inspiratory and expiratory stridor, which
have been present since birth. In addition, the bronchoscopy shows
severe tracheal stenosis. We have recommended operative repair
in all patients through a median sternotomy approach with
extracorporeal circulation and reimplantation of the left
pulmonary artery anterior to the trachea. The early results of
this series (12 patients) were reported in 1992.2
Our experience with pulmonary artery sling surgery now includes
22 patients. There have been no operative deaths in this series. There
were 2 late deaths, both in patients with associated complete tracheal
rings and complex tracheal reconstruction. The other patients have all
had a complete resolution of their symptoms. My recommendation in a
child with a pulmonary artery sling in all cases would be
repair at the time of diagnosis.
In summary, it is my feeling that pulmonary artery angiography
and tracheobronchography are rarely, if ever, indicated in patients
with pulmonary artery sling. These patients should be evaluated
with echocardiography and bronchoscopy. In
addition, it is my strong feeling that all patients with symptoms and a
pulmonary artery sling should have such malformations repaired
at the time of diagnosis and should not be cared for with medical
management.
References
1.
Alboliras ET, Backer CL, Holinger LD, Mavroudis C.
Pulmonary artery sling: diagnostic and management
strategy. Pediatrics. 1996;98:530. Abstract.
2.
Backer CL, Idriss FS, Holinger LD, Mavroudis C.
Pulmonary artery sling: results of surgical repair in infancy.
J Thorac Cardiovasc Surg. 1992;103:683–691.[Abstract]
Response
Joachim Freihorst, MD;
; Thomas Paul, MD
Children's Hospital,
Hannover Medical School,
Hannover, FR Germany
We appreciate the comments of Dr Backer about the feasibility of
2-dimensional echocardiography in the
diagnostic workup of patients with pulmonary artery
sling. We believe, however, that pulmonary angiography is still
a helpful tool in establishing the correct diagnosis, since
echocardiography alone may not always be 100%
predictive even in experienced centers.1
Pulmonary artery sling is such a rare entity that each center
should keep and follow the procedures it feels most comfortable with.
In patients with pulmonary artery sling diagnosed or suspected
by echocardiography, we proceed with combined
angiography and tracheobronchoscopy as well as tracheobronchography. In
our experience, pulmonary artery sling could be diagnosed by
angiography in all 12 patients evaluated during the last 20 years.
Preoperative simultaneous examination of the
tracheobronchial anatomy by tracheobronchoscopy and
tracheobronchography is essential for planning the optimal surgical
procedure for each individual patient.2 3
We believe that surgical treatment is not always necessary in patients
with pulmonary artery sling. Indication for surgical
intervention should be made on an individual basis according to the
severity of symptoms and results of lung function studies. Some
children with pulmonary artery sling may have normal physical
capacity and development with only minor respiratory problems without
surgery, as demonstrated in our patient.
References
1.
Burch M, Balaji S, Deanfield JE, Sullivan ID.
Investigation of vascular compression of the trachea: the complementary
roles of barium swallow and echocardiography.
Arch Dis Child. 1993;68:171–176.[Abstract/Free Full Text]
2.
Valletta EA, Pregarz M, Bergamo-Andreis IA, Boner AL.
Tracheoesophageal compression due to congenital vascular anomalies
(vascular rings). Pediatr Pulmonol. 1997;24:93–105.[Medline]
[Order article via Infotrieve]
3.
Ziemer G, Heinemann M, Kaulitz R, Freihorst J,
Seidenberg J, Wilken M. Pulmonary artery sling with tracheal
stenosis: primary one-stage repair in infancy. Ann
Thorac Surg. 1992;54:971–973.[Abstract]
