Keywords pseudoaneurysm - innominate artery - stent
Introduction
A tracheoinnominate artery fistula (TIF) is a rare complication following tracheostomy.
The mortality rate of this complication is 100% if untreated, making prompt diagnosis
and management critical to ensure survival.[1 ] Interventions using an open repair strategy have even shown mortality rates approaching
50%.[2 ] Minimally invasive approaches to treatment may prove to be a safer alternative to
open repair; however, there is a paucity of literature on this topic, especially in
the pediatric setting. Here, we describe a case of TIF in a 10-year-old girl treated
with endovascular stent graft placement.
Case Summary
A 10-year-old girl with metachromatic leukodystrophy and epilepsy underwent tracheostomy
at an outside institution due to chronic respiratory failure. One month after the
tracheostomy creation, she presented acutely at the outside institution with large
volume hemoptysis within and around her tracheostomy. Imaging at that time confirmed
a low tracheostomy in close approximation with the innominate artery ([Fig. 1 ]), presumably leading to erosion of the artery with bleeding through pressure necrosis
of the anterior wall of the trachea. Bleeding was temporized by a cuffed endotracheal
tube and a pressure dressing at the neck.
Fig. 1 Semi-upright chest radiograph (A) and sagittal CTA (B) depicting the low tracheostomy placement abutting the innominate artery.
The patient was transferred emergently to our institution for surgical correction.
The great vessels and trachea were exposed via median sternotomy. A 2.5-mm defect
was identified in the cephalad aspect of the innominate artery and repaired using
sutured pericardial pledgets. The tracheotomy was exposed and sealed with sutured
pericardial pledget. A sternocleidomastoid muscle flap was then mobilized and interposed
between the repaired innominate artery and tracheotomy. She did well immediately postprocedure
and underwent a new, more superiorly placed tracheostomy placement on hospital day
17. Her tracheostomy was changed and evaluated on hospital day 24. She continued to
recover well with no recurrent hemoptysis and was transferred to her home state for
continued management 30 days postsurgical repair.
Upon arrival to the outside hospital, the patient had recurrent massive hemoptysis
via her tracheostomy. After approximately 250 mL of expectorated blood loss, bleeding
was controlled with a cuffed endotracheal tube. Her presentation was notable for acidosis
to 7.01 on arterial blood gas as well as acute blood loss requiring transfusion. She
was immediately transferred back to our institution. Arterial-phase computed tomography
(CTA) confirmed the presence of an innominate artery pseudoaneurysm ([Fig. 2 ]), and the patient was taken emergently to the angiography suite (now day 31 since
original TIF repair). A long 8F 65-cm vascular sheath (Pinnacle Destination, Terumo
Medical) was placed following right femoral artery access. A 4F angled catheter and
0.035-in hydrophilic wire were used to select the innominate and then the right subclavian
artery. Innominate artery angiograms were acquired in multiple projections, confirming
a 2- × 3- × 3-mm pseudoaneurysm of the superior surface of the innominate artery ([Fig. 3 ]).
Fig. 2 Three-dimensional surface rendering of CTA displaying an innominate artery pseudoaneurysm
(arrow).
Fig. 3 Digital subtraction angiogram depicting a pseudoaneurysm on the superior surface
of the innominate artery, 1 mm proximal to the origin of the right common carotid
artery, without angiographic extravasation (arrow).
The sheath was advanced into the right subclavian artery with its dilator, and the
dilator was then removed. A 7 × 19 mm balloon expandable stent graft (Viabahn VBX,
W.L. Gore & Associates) was positioned in the innominate artery ([Fig. 4 ]) and deployed to nominal diameter. An 8 × 20 mm balloon was introduced and inflated
across the proximal aspects of the stent graft for improved apposition to the arterial
wall. Completion angiogram confirmed complete exclusion of the pseudoaneurysm with
patent great vessels and no endoleak ([Fig. 5 ]).
Fig. 4 Digital subtraction angiogram of the innominate artery for stent graft positioning
prior to deployment.
Fig. 5 Digital subtraction angiogram of the innominate artery following stent graft deployment,
confirming pseudoaneurysm exclusion, great vessel patency, and no endoleak.
Following stent graft deployment, endotracheal tube cuff was deflated and hemostasis
was confirmed. The patient tolerated the procedure well and was transferred back to
the intensive care unit (ICU) in stable condition. Although the patient displayed
no clinical signs of a mycotic component to her recurrent pseudoaneurysm, broad-spectrum
intravenous antibiotics were initiated periprocedurally and continued for 72 hours
with piperacillin/tazobactam 2,025 mg intravenous every 8 hours. A daily aspirin was
initiated on the first postprocedure day for prophylaxis against stent graft thrombosis
and cerebrovascular complications. She remained in the ICU while weaning her ventilator
settings and sedation, ultimately returning to her baseline and being discharged home
2 weeks status post stent-graft placement. At the time of preparing this article,
4 months since placement, she has recovered well with no further episodes of hemoptysis.
She is followed expectantly with a planned surveillance CTA 1 year from the procedure.
Aspirin will continue indefinitely unless contraindicated.
Discussion
Tracheoinnominate artery fistula formation is a life-threatening complication of tracheostomy.
The formation rate remains low in the reported literature (0.2–0.7%); however, the
mortality rate is still significant.[3 ] In a review of 1,130 cases of tracheostomy placement in children, Goldenberg et
al found only 2 reported instances of TIF formation, both of which were fatal.[3 ] Survival without treatment of the TIF has never been reported.[1 ]
Tracheoinnominate artery fistulas predominantly occur between the first and second
weeks after tracheostomy, most commonly due to erosion of the innominate artery vessel
by the inferior neck of a rigid tracheostomy tube that is placed too low. Also, an
anomalously high innominate artery, more common in thin and younger patients, places
patients at higher risk. Because of this, tracheostomy tubes should not be placed
below the third tracheal ring. Additional factors that may predispose individuals
to TIF formation include overinflating of cuffs, tracheostomy tubes with adjustable
flanges, and positive airway pressure.[4 ]
Several classic clinical features should raise suspicion for a TIF. Any peristomal
bleeding and hemoptysis warrant clinical evaluation. Bleeding witnessed within 48
hours of tracheostomy is typically not associated with a TIF, rather from a possible
traumatic puncture of local venous structures, a coagulopathy, or from traumatic tracheal
secretion suctioning. On the other hand, bleeding that occurs between 3 days and 6
weeks after tracheostomy is a TIF until proven otherwise. A sentinel small peristomal
bleed that spontaneously resolves occasionally precedes more massive hemoptysis. A
pulsating tracheostomy suggests close proximity to a major artery and should raise
suspicion for TIF. Placement of a cuffed tracheostomy tube is a critical temporizing
measure and helps confirm the diagnosis if hemoptysis ceases.
Historically, open surgical repair has been the treatment of choice for TIF. Unfortunately,
mortality rates for open repair exceed 50% in previous reviews, and long-term survival
is poor with only 8 to 56% of patients living beyond 2 months.[2 ] Given the poor surgical outcomes, investigation of alternative treatment is warranted.
Operators taking an endovascular approach may have concerns for the use of synthetic
materials in the proximity of a likely infected area. In addressing this issue, Sorial
et al assembled outcomes of various endovascular attempts to treat TIF, and of the
five cases presented, none had any reported infectious complications.[1 ]
A literature review yielded 13 published cases of TIF treated endovascularly. Only
four of these cases have been in children. Takasaki et al reported a case of a 9-year-old
boy with TIF successfully treated by embolization of the innominate artery.[4 ] The case reported by Vianello and colleagues is the first known successful stent
grafting in a pediatric case.[5 ] Further reports have continued to use stent grafting as the treatment choice in
children with success and known stable outcomes at several weeks to 24 months after
the procedure.[6 ]
[7 ]
[8 ]
Endovascular treatment was pursued after the patient recurred postsurgical repair
as repeat surgical exploration was considered to carry unacceptable risks. The endovascular
approach allows rapid control of bleeding while avoiding the morbidity of a median
sternotomy, and we speculate a more favorable course had the patient been treated
primarily in this manner. Meanwhile, we acknowledge limitations in the assessment
of treatment durability and a generalized lack of available literature on long-term
outcomes. Furthermore, airway continuity with the vascular injury introduces the potential
for stent graft infection and associated complications that could necessitate surgical
correction. Our review identified no cases of endovascular material infection, but
the sparse amount of available data is insufficient to dismiss this possibility and
we recommend broad-spectrum periprocedural antibiosis until further guidance becomes
available. In the absence of antiplatelet guidance specific to stenting for this condition,
we have extrapolated our plan for indefinite daily aspirin therapy from the iliac
artery covered stent literature.
TIFs present a formidable treatment challenge. A limited but growing body of literature
supports endovascular repair. Here, we have presented a case of a TIF in a 10-year-old
girl treated with endovascular stent graft placement following a recurrence after
surgical treatment. The procedure was uncomplicated, successful, and well tolerated,
adding to the evidence that endovascular stent grafting of the innominate artery can
be a safe treatment option for TIF in the pediatric population.
Ethical Approval
All procedures performed in studies involving human participants were in accordance
with the ethical standards of the institutional and/or national research committee
and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical
standards.
Informed Consent
Does not apply.
