AJR 2001; 176:1032-1034
© American Roentgen Ray Society
Sonographically Guided Percutaneous Thrombin Injection for Treatment of a Vein Graft Pseudoaneurysm
Michael A. Farrell1,
Bruce R. Douglas1 and
Thomas C. Bower2
1
Department of Radiology, Mayo Clinic, 200 First St. S.W., Rochester, MN
55905.
2
Department of Vascular Surgery, Mayo Clinic, Rochester, MN 55905.
Received July 31, 2000;
accepted after revision September 21, 2000.
Address correspondence to M. A. Farrell.
Introduction
Direct percutaneous thrombin injection under sonographic guidance has
recently been advocated as a safe treatment for iatrogenic femoral
pseudoaneurysms [1]. We
describe a new application of this technique to successfully treat a
pseudoaneurysm arising as a result of vein grafting.
A 65-year-old man with diabetes and extensive atherosclerotic disease
underwent left popliteal artery-to-dorsalis pedis artery bypass grafting for
treatment of an ischemic foot ulcer. The graft used was a reversed composite
graft of the cephalic and basilic veins. Intraoperative arteriography revealed
a widely patent bypass graft. On the seventh postoperative day the patient
complained of calf pain and had mild leg swelling. Sonography showed a 2-cm
pseudoaneurysm arising from the vein graft 4 cm beyond the proximal popliteal
artery graft anastomosis and the adjacent hematoma. Arteriography was
performed in preparation for operative repair of the pseudoaneurysm. This
study showed the pseudoaneurysm to have a very narrow neck, likely at the site
of a branch of the vein graft (Fig.
1A). Because the patient had only mild symptoms, the remainder of
the vein graft had normal flow characteristics, the pseudoaneurysm had a
narrow neck, and our early experience with thrombin injection of iatrogenic
femoral pseudoaneurysms was good, we decided that sonographically guided
direct thrombin injection was feasible in this situation. The patient did not
undergo anticoagulation. Clotting parameters had been normal 5 days before the
procedure and were not rechecked.
View larger version (103K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —65-year-old man 7 days after popliteal artery-to-dorsalis
pedis artery vein bypass grafting. Left leg digital subtraction angiogram with
catheter (not shown) in left superficial femoral artery, which was accessed
via right common femoral artery, shows 2-cm pseudoaneurysm (arrow)
arising proximally in popliteal artery-to-dorsalis pedis artery vein
graft.
|
|
The periphery of the pseudoaneurysm was identified, and the pseudoaneurysm
was injected under real-time duplex sonography (Sequoia 512; Acuson, Mountain
View, CA) with a curvilinear probe using a Doppler emission frequency of 6
MHz. Under sterile conditions with the use of a 3.5-inch 22-gauge spinal
needle (Sherwood Medical, St. Louis, MO) a total of 1.1 mL of thrombin (1000
U/mL of topical USP [bovine origin] thrombin, Thrombin-JMI; GenTrac,
Middleton, WI) was injected in increments of 0.1 mL under constant sonographic
imaging (Fig. 1B). The 0.1-mL
bolus was injected over a period of 3 sec with an interval of approximately 5
sec between injections to evaluate whether thrombosis had occurred. After
injection of 0.7 mL, approximately 75% of the pseudoaneurysm cavity had
thrombosed. The needle was repositioned into the area of persistent flow. An
additional 0.4 mL of thrombin was injected into the remaining cavity, and
complete thrombosis of the pseudoaneurysm occurred
(Fig. 1C). Repeated sonographic
examinations 1 day and 1 month after the procedure showed no evidence of a
recurrent false aneurysm. The bypass graft remained widely patent. The patient
was discharged the day after thrombin injection and the subsequent sonographic
examination.
View larger version (86K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —65-year-old man 7 days after popliteal artery-to-dorsalis
pedis artery vein bypass grafting. Transverse B-mode sonogram shows echogenic
needle (arrows) with tip in pseudoaneurysm lumen.
|
|
View larger version (92K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1C. —65-year-old man 7 days after popliteal artery-to-dorsalis
pedis artery vein bypass grafting. Transverse color Doppler sonogram obtained
immediately after thrombin injection reveals complete thrombosis
(arrows) of pseudoaneurysm adjacent to patent venous graft.
|
|
Discussion
Vein grafts are used preferentially as conduits for lower extremity
arterial reconstruction in patients with limb-threatening ischemia because
vein grafts have better patency rates than synthetic grafts
[2,3,4].
When veins are used, whether in a reversed or non-reversed fashion, the side
branches of the vein graft are ligated. False aneurysms in these grafts are
rare. In our patient, the pseudoaneurysm arose at a site of a collateral side
branch, likely because of the loosening of a ligature. Although disruption of
the side branch of the vein graft may occur early after an operation, it often
results in clinically significant hemorrhage or it causes a compressive
hematoma around the graft. Neither of these sequelae occurred in our patient.
These complications are often repaired operatively.
Sonographically guided injection of thrombin into the lumen of a
pseudoaneurysm has recently been reported as a means to obliterate the false
aneurysm cavity and obviate operative repair
[1,
5,
6]. Initially, this technique
was used to treat iatrogenic femoral pseudoaneurysms, but more recently Kang
et al. [7] have used thrombin
injection to treat pseudoaneurysns caused by gunshot wounds, trauma, and false
aneurysms associated with the removal of an infected arteriovenous graft. To
our knowledge, there are no reported cases in the literature using
sonographically guided thrombin injection to treat a vein graft pseudoaneurysm
arising from a side branch.
Sonographically guided thrombin injection offers another alternative to
compression in treatment of patients with false aneurysms. Thrombin is an
enzyme that transforms fibrinogen into fibrin, a critical component of blood
coagulation and thrombosis. Contact of thrombin with the blood within the
cavity of a pseudoaneurysm causes local thrombosis thereby obliterating the
cavity. We do not routinely check clotting parameters before thrombin
injection, and we have previously injected pseudoaneurysms in patients who are
being anticoagulated with IV heparin. Anticoagulation does not appear to
influence the amount of thrombin necessary for successful thrombosis nor does
it appear to increase the recurrence rate compared with those patients who are
not undergoing anticoagulation therapy
[5]. Heparin inhibits the
conversion of prothrombin to thrombin and, therefore, does not affect the
formation of thrombus associated with the instillation of thrombin.
The most worrisome complication with this technique is distal embolization
or thrombosis of the underlying native artery. Only two such complications
have been reported thus far in the literature, both of which involved
treatment of false aneurysms of the brachial artery. Only one of these
patients (a 10-month-old infant) required arterial thrombectomy
[7,
8]. Although it is reasonable
to assume that aneurysms with a short, wide neck are at greater risk for clot
displacement from the pseudoaneurysm and distal embolization, pseudoaneurysms
with a neck as short as 5 mm and as wide as 4.3 mm have been safely treated
with this technique [6]. By
careful placement of the needle tip away from the neck of the false aneurysm,
incremental injection of small volumes of thrombin can be performed during
continuous observation on color flow Doppler imaging. This technique minimizes
the risk of distal embolization and native artery thrombosis. A relatively
large dose of thrombin (1.1 mL) was required to achieve thrombosis of the
pseudoaneurysm in our patient.
The amount of thrombin necessary to achieve thrombosis has varied among
published series. In one report, no patient required more than 0.6 mL of
thrombin to achieve thrombosis of pseudoaneurysms ranging in size from 1.2 to
3.6 cm [6]. In contrast,
another study of 83 patients treated with this technique showed no correlation
between the size of the pseudoaneurysm and the amount of thrombin required for
successful thrombosis [7].
This case describes a technical innovation in which a small localized vein
graft pseudoaneurysm with a narrow neck was successfully treated with
percutaneous thrombin injection. This technique offers an option for the
treatment of patients with false aneurysms originating from side branches of a
vein graft in patients who are clinically stable and have narrow-necked
pseudoaneurysms that are readily accessible to percutaneous imaging and that
can be accessed for injection. Patients with large acute or chronic false
aneurysms, those with vein graft side branch disruption with large hematomas,
vein graft compression, or hemodynamic instability are best treated
operatively.
References
-
Brophy DP, Sheiman RG, Amatulle P, Akbari CM. Iatrogenic femoral
pseudoaneurysms: thrombin injection after failed US-guided compression.
Radiology
2000;214:278
-282[Abstract/Free Full Text]
-
Andros G, Harris RW, Salles-Cunha SX, Dulawa LB, Oblath RW, Apyan
RL. Bypass grafts to the ankle and foot. J Vasc Surg
1988;7:785
-794[Medline]
-
Panayiotopoulos YP, Tyrrell MR, Owen SE, Reidy JF, Taylor PR.
Outcome and cost analysis after femorocrural and femoropedal grafting for
critical limb ischaemia. Br J Surg
1997;84:207
-212[Medline]
-
Veith FJ, Gupta SK, Ascer E, et al. Six-year prospective
multicenter randomized comparison of autologous saphenous vein and expanded
polytetrafluoroethylene grafts in infrainguinal arterial reconstructions.
J Vasc Surg
1986;3:104
-114[Medline]
-
Kang SS, Labropoulos N, Mansour MA, Baker WH. Percutaneous
ultrasound guided thrombin injection: a new method for treating
postcatheterization femoral pseudoaneurysms. J Vasc
Surg 1998;27:1032
-1038[Medline]
-
Paulson EK, Sheafor DH, Kliewer MA, Nelson RC, Eisenberg LB,
Sebastian MW, Sketch MH, Jr. Treatment of iatrogenic femoral arterial
pseudoaneurysms: comparison of US-guided thrombin injection with compression
repair. Radiology
2000;215:403
-408[Abstract/Free Full Text]
-
Kang SS, Labropoulos N, Mansour MA, et al. Expanded indications for
ultrasound-guided thrombin injection of pseudoaneurysms. J Vasc
Surg 2000;31:289
-298[Medline]
-
Lennox A, Griffin M, Nicolaides A, Mansfield A. Percutaneous
ultrasound guided thrombin injection: a new method for treating
postcatheterization femoral pseudoaneurysms. (letter) J Vasc
Surg 1998;28:1120
-1121[Medline]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
Top
Introduction
Discussion
