Summary:
Prepared by Jay Radhakrishnan, MD and Jose Yrizarry, MD
from the Department of Vascular/Interventional Radiology at the
University of Miami/Jackson Memorial Hospital, Miami, FL.
Summary: A 33-year-old male pedestrian was struck by an automobile. The
patient presented to the emergency department with complete loss of
sensory and motor function of the left upper extremity, as well as
absence of pulses in the left upper extremity from the shoulder to
the hand. Computed tomography scan of the chest (not shown) showed
a large mediastinal hematoma with injury to the left subclavian
artery. The patient was taken to the operating room for exploration
and was found to have a large hematoma around the left subclavian
artery, which dissected along the left carotid sheath, as well as
complete avulsion of the left brachial plexus from the cervical
spine. Surgical exploration was terminated and the patient was
brought to special procedures for embolization of the left
subclavian artery for proximal hemostasis control prior to
amputation of the left upper extremity.
Diagnosis
Posttraumatic occlusion of the left subclavian artery and partial
avulsion of the left vertebral artery
Findings
Scout film of the chest shows increased opacification in the
left hemithorax as well as fractures of the first and second ribs
(figure 1). Thoracic aortagram shows complete occlusion of the left
subclavian artery (figure 2) distal to the takeoff of the left
vertebral artery. A magnified view of this area confirms the
occluded left subclavian artery and also reveals a large filling
defect in the proximal portion of the left vertebral artery (figure
3), which was believed to represent a partial avulsion of this
vessel. Multiple Guglielmi (GDC) coils (Boston Scientific, Fremont,
CA) were then placed into the left subclavian artery but showed
significant residual flow in the major branches on the post coil
angiogram (figure 4). At this time, multiple Tornado coils (Cook
Inc., Bloomington, IN) were placed selectively in the left
vertebral artery, thyrocervical trunk, and left internal mammary
artery, and showed no significant flow through these vessels
following coil placement (figure 5). The procedure was terminated,
and the patient underwent uneventful amputation of the left upper
extremity approximately 24 hours later.
Discussion
This case clearly illustrates how the interventional radiologist
can play an important role in aiding the vascular surgeon in
preoperative embolization of an area in which controlled hemostasis
is difficult due to the nature and location of the injury. Not only
was there complete occlusion of the left subclavian artery, but a
partial avulsion of the left vertebral artery. Initial surgical
exploration confirmed a hematoma around the left subclavian artery
that was difficult to mobilize due to its proximity to other major
branches as well as the carotid sheath. In addition, the fact that
the patient had complete avulsion of the brachial plexus, absence
of sensory and motor function, and complete loss of pulses in the
left upper extremity led to the decision to amputate the left upper
extremity following embolization. The initial selection of
Guglielmi coils proved to be ineffective in this case due to the
location of the injury. However, following selective placement of
multiple Tornado coils, there was no residual flow in the target
vessels. As a result, the patient underwent uneventful amputation
of the left upper extremity following embolization.