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250 Medical treatment of acute deep venous thrombosis and pulmonary embolism
https://t.me/med1917
●
31. Gabriel F, Portolés O, Labiós M etal. Usefulness of
thrombophilia testing in venous thromboembolic
disease: Findings from the RIETE Registry. Clin Appl
Thromb Hemost 2013;19(1) :42–7.
●
32. Palareti G, Cosmi B, Legnani C etal. D-dimer testing to determine the duration of anticoagulation
therapy. N Engl J Med 20 06;355(17):1780–9.
33. Crowther MA and Warkentin TE. Bleeding risk
and the management of bleeding complications
in patients undergoing anticoagulant therapy:
Focus on new anticoagulant agents. Blood
2008;111(10 ):4871–9.
★
34. Yeh CH, Gross PL, and Weitz JI. Evolving use of new
oral anticoagulants for treatment of venous thromboembolism. Blood 2014;124(7):1020–8.
35. Greinacher A, Michels I, and Mueller-Eckhardt C.
Heparin-associated thrombocytopenia: The antibody is not heparin specific. Thromb Haemost
1992;67(5):545–9.
★
36. Martel N, Lee J, and Wells PS. Risk for heparin-induced thrombocytopenia with unfractionated and low-molecular-weight heparin
thromboprophylaxis: Ameta-analysis. Blood
2005;106(8):2710–5.
★
37. Alving BM. How I treat heparin-induced thrombocytopenia and thrombosis. Blood 2003;101(1):31–7.
38. Prandoni P, Lensing AW, Prins MH etal. Below-knee
elastic compression stockings to prevent the postthrombotic syndrome: A randomized, controlled
trial. Ann Intern Med 2004;141(4):249–56.
39. Aschwanden M, Labs KH, Engel H etal. Acute
deep vein thrombosis: Early mobilization does not
increase the frequency of pulmonary embolism.
Thromb Haemost 2001;85(1):42–6.
●
40. Kahn SR, Shapiro S, Wells PS etal. Compression
stockings to prevent post-thrombotic syndrome:
A randomised placebo-controlled trial. Lancet
2014;383(9920):880–8.
●
41. Prandoni P, Lensing AW, Cogo A etal. The long-term
clinical course of acute deep venous thrombosis.
Ann Intern Med 1996;125(1):1–7.
★
42. Wakefield TW, Myers DD, and Henke PK.
Mechanisms of venous thrombosis and resolution.
Arterioscler Thromb Vasc Biol 2008;28(3):387–91.
●
43. Meissner MH, Manzo RA, Bergelin RO, Markel A,
and Strandness DE Jr. Deep venous insufficiency:
The relationship between lysis and subsequent
reflux. J Vasc Surg 1993;18(4):596–605; discussion
606–8.
44. Juhan CM, Alimi YS, Barthelemy PJ, Fabre DF, and
Riviere CS. Late results of iliofemoral venous thrombectomy. J Vasc Surg 1997;25(3):417–22.
●
45. Enden T HY, Kløw NE, Slagsvold CE etal.; CaVenT
Study Group. Long-term outcome after additional
catheter-directed thrombolysis versus standard
treatment for acute iliofemoral deep vein thrombosis
(the CaVenT study): A randomised controlled trial.
Lancet 2012;379:31–8.
46. Baekgaard NBR, Just S, Jørgensen M, and Jensen
LP. Long-term results using catheter-directed
thrombolysis in 103 lower limbs with acute iliofemoral venous thrombosis. Eur J Vasc Endovasc Surg
2010;39(1):112–7.
47. Raju S, Darcey R, and Neglén P. Unexpected major
role for venous stenting in deep reflux disease. J
Vasc Surg 2010;51(2):401–8.
●
48. Kearon C, Akl EA, Ornelas J etal.; Antithrombotic
therapy for VTE disease: CHEST guideline and
expert panel report. Chest 2016;149(2):315–52.
★
49. Marti C, John G, Konstantinides S etal. Systemic
thrombolytic therapy for acute pulmonary embolism:A systematic review and meta-analysis. Eur
Heart J 2014;2015;36(10):605–14.
●
50. Meyer G, Vicaut E, Danays T etal. Fibrinolysis for
patients with intermediate-risk pulmonary embolism.
N Engl J Med 2014;370(15):1402–11.
★
51. Rodger M. Evidence base for the management of venous thromboembolism in pregnancy.
HematologyAm Soc Hematol Educ Program
2010;2010:173–80.
●
52. Goldhaber SZ. Risk factors for venous thromboembolism. J Am Coll Cardiol 2010;56(1):1 – 7.
★
53. Hirsh J and Lee AY. How we diagnose and treat deep
vein thrombosis. Blood 2002;99(9):3102–10.
★
54. Greenfield LJ and Proctor MC. Current status of inferiorvena cava filters. Ann Vasc Surg
2000;14(5):525–8.
●
55. PREPIC Study Group. Eight-year follow-up of
patients with permanent vena cava filters in the
prevention of pulmonary embolism The PREPIC
(Prévention du Risque d’Embolie Pulmonaire par
Interruption Cave) randomized study. Circulation
2005;112(3):416–22.
56. Meissner MH, Gloviczki P, Comerota AJ etal.
Early thrombus removal strategies for acute deep
venous thrombosis: Clinical practice guidelines of
the Society for Vascular Surgery and the American
Venous Forum. J Vasc Surg 2012;55:1449– 62.
20
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Catheter-directed thrombolysis, mechanical
thrombectomy, and surgery for the treatment
of acute iliofemoral deep venous thrombosis
ARTHUR DELOS REYES AND ANTHONY J. COMEROTA
20.1 Introduction 251
20.2 Rationale for removal ofthrombus 251
20.3 Published guidelines andevidence 251
20.4 Pre-treatment evaluation 253
20.5 Intrathrombus CDT 254
20.1 INTRODUCTION
Venous thromboembolic disease aects over 900,000 individuals annually in the United States,1 and remains a major
source of morbidity and mortality throughout the world.
Current therapy focuses on preventing the embolization
of deep venous thrombosis (DVT), for which anticoagulation remains the cornerstone of treatment. Anticoagulation
alone has been shown to reduce the incidence of pulmonary embolism (PE) and death in multiple randomized trials,2 thus reducing the early complications associated with
DVT. However, anticoagulation does not prevent or treat
the development of post-thrombotic syndrome (PTS),
most signicant late complication of venous thromboembolic disease.
PTS is dened as a constellation of signs and symptoms
in the aected extremity that occur aer acute DVT; PTS is
generally evident within the rst few months aer the diagnosis (and treatment) of DVT.6 Clinical manifestations progress over time and include chronic pain, edema, varicosities,
pigmentation, eczema, and ulceration in severe cases, which
have a signicant impact on quality of life.
incidence of PTS varies, due in part to the variability and
precision of the follow-up of patients aer their acute DVT.
In the United States, PTS is estimated to aect up to half of
all people who have a DVT. PTS aects up to 6 million individuals, and ulceration exists in 400,000–500,000 patients
who have suered a DVT.
10
A large body of evidence reveals
7–9
e reported
3–5
the
20.6 Pharmacomechanical thrombolysis 256
20.7 Operative venous thrombectomy 257
20.8 Post-operative care 260
References 261
that PTS is more prevalent and severe following iliofemoral
DVT if treatment involves anticoagulation alone.
4,6
20.2 RATIONALE FOR REMOVAL
OFTHROMBUS
Ambulatory venous hypertension is the underlying pathophysiology of chronic venous disease.
tence and venous obstruction—consequences of iliofemoral
DVT—are associated with the most severe post-thrombotic
morbidity.12 us, the underlying rationale for thrombus
removal in patients with iliofemoral DVT is that eliminating
the acute clot avoids or reduces chronic venous obstruction
(Figure 20.1), resulting in marked reduction of the PTS.
5,11
Valvular incompe-
4,12,13
20.3 PUBLISHED GUIDELINES
ANDEVIDENCE
In 2012, the Society for Vascular Surgery published guidelines titled Early rombus Removal Strategies for Acute Deep
Venous rombosis: Clinical Practice Guidelines of the Society
for Vascular Surgery and the American Venous Forum.
2.1 We suggest a strategy of early thrombus
removal in selected patients meeting the following criteria: (a) first episode of acute iliofemoral deep venous thrombosis, (b) symptoms <14
14
251
252 Catheter-directed thrombolysis, mechanical thrombectomy, and surgery
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(a)
(b)
Figure 20.1 (a and b) Post-thrombotic venous disease
illustrating the inability to identify obstruction as part
of the pathophysiology of chronic venous disease. This
patient had suffered from iliofemoral deep venous thrombosis 10 years earlier and was treated with anticoagulation alone. Severe post-thrombotic syndrome developed,
and the patient underwent multiple hospitalizations for
venous ulceration. An ascending phlebogram showed
recanalization of the iliofemoral venous system; however,
the radiologist’s interpretation was that there was “no
obstruction” of the deep venous system, and a 3-second
maximal venous outflow test was “normal.” A classic
Linton procedure was performed and showed (insert)
the cross-section of the femoral vein at the corresponding location on the phlebogram, just below the profunda
femoris vein.
days, (c) a low risk of bleeding, and (d) ambulatory with good functional capacity and an
acceptable life expectancy (Grade 2C).
In 2014, the American Heart Association (AHA)
released a consensus statement entitled e Postthrombotic
Syndrome: Evidence-Based Prevention, Diagnosis, and
Treatment Strategies. eir recommendations for throm-
bolysis and endovascular approaches to acute DVT for the
6
prevention of PTS state the following
:
[Catheter-directed thrombolysis] and [pharmacomechanical catheter-directed thrombolysis]
in experienced centers, may be considered in
select patients with acute (<14 days) symptomatic, extensive proximal DVT who have good
functional capacity, >1 year life expectancy, and
low expected bleeding risk (Class IIb, Level of
Evidence B).
Controversies surrounding the use of thrombolytic
therapy to prevent the development of PTS persist. Most
notably, the American College of Chest Physicians (ACCP)
Consensus Committee has wavered on its recommendation
regarding the use of thrombolysis for treatment of proximal DVT. In the Antithrombotic erapy for VTE Disease,
published in 2012, the ninth ACCP guideline recommenda-
15
tion states the following
:
2.9 In patients with acute proximal DVT of the
leg, we suggest anticoagulation therapy alone
over catheter-directed thrombolysis (CDT)
(Grade 2C).
is redacts the eighth ACCP Consensus Committee
recommendation published in 2008 for thrombus removal
in patients with proximal DVT. At the time, prevailing evidence suggested that operative venous thrombectomy or
CDT was recommended for patients with acute iliofemoral
DVT to reduce acute symptoms and post-thrombotic morbidity (grade 2B).2 e eighth ACCP consensus committee
recognized that iliofemoral DVT was an important subset
of patients deserving of added attention for a treatment
strategy of thrombus removal.
Both the AHA and ACCP base their recommendations
on the available published research. In this case, the strict
method to include “evidence” used by the ACCP in 2012
compared to 2008 excluded all non-randomized controlled
trials and did not include other evidence. Despite the available evidence, the use of the decided-upon criteria resulted
in no study or treatment meeting the ACCP 2012 criteria
for a grade 1A recommendation for any treatment of acute
venous thromboembolic disease. Unfortunately, the ninth
ACCP edition reverted to the generic “proximal DVT” classication and did not recognize iliofemoral deep venous
thrombosis (IFDVT) as an important subset of patients facing more frequent and severe post-thrombotic morbidity.
Much of the evidence supporting thrombolysis for
the treatment of iliofemoral DVT to prevent PTS is from
single-center, non-randomized studies, although a more
recent multicenter trial showed benets of CDT. In the
Catheter-Directed rombolysis in Acute Iliofemoral Vein
rombosis (CaVenT) trial, 209 patients were randomized
to CDT plus anticoagulation or anticoagulation alone.4
e addition of CDT resulted in a signicant reduction in
PTS compared to anticoagulation alone. In the rombus
Obliteration by Rapid Percutaneous Endovenous
Intervention in Deep Venous Occlusion (TORPEDO)
trial, pharmacomechanical catheter directed thrombolysis
(PCDT) plus anticoagulation was tested against anticoagulation alone in 183 patients with DVT. Once again, PCDT
plus anticoagulation showed a signicant reduction in risk
of PTS in the treatment group. e use of a non-standard
measure of PTS and non-blinding of the clinical observers
limits the strength of these results.
6
e National Institutes of Health (NIH) has sponsored
the Acute Venous rombosis: rombosis Removal with
Adjunctive Catheter-directed rombolysis (ATTRACT)
trial. is is a multicenter, randomized, open-label, asses-
16,17
sor-blinded, parallel, two-arm, controlled clinical trial.
ATTRACT met its recruitment goal of randomizing
692 patients in December of 2014. Patients were stratied at entry to iliofemoral DVT or femoropopliteal DVT
Symptomatic proximal DVT
The ATTRACT Trial
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Stratify
20.4 Pre-treatment evaluation 253
Femoral-popliteal DVTIlio-femoral DVT
RandomizeRandomize
Catheter based
thrombus removal
-plus-
anticoagulation
Villalta score
CEAP classication
QOL evaluation
Figure 20.2 Algorithm of the protocol of the ATTRACT trial. DVT: deep venous thrombosis; QOL: quality of life.
Anticoagulation
alone
Postthrombotic syndrome
during 24-month follow-up
Venous clinical severity score
Venous duplex -patency
(Figure20.2). A total of 692 patients have been randomized.
e ATTRACT trial is now into its 2-year follow-up phase
for assessing its primary ecacy endpoint of PTS. Results
are anticipated in early 2017.
Based upon all of the available evidence to date, and
based upon the increased safety of CDT infusing low
doses of a plasminogen activation in high volumes of
saline (1 mg in 50–100 cc/hour), which improves ecacy,
we would suggest that CDT for iliofemoral DVT be given
a strong recommendation (level 1) supported by grade B
evidence.
Catheter based
thrombus removal
-plus-
anticoagulation
-valve function
complication of either lytic therapy or venous thrombectomy, rather than a delayed manifestation of a pre-existing
PE. Additionally, the CT scan oen identies other thoracic, abdominal, or pelvic pathologies (see Figure 20.3b).
Martinez and colleagues reviewed the results of CT scan
evaluations for 47patients with iliofemoral DVT and found
PE in 48% and other unexpected thoracic, abdominal, or
pelvic pathologies in 23%.
tumors, retroperitoneal lymphoma, pulmonary adenocarcinoma, hepatic metastases, iliac vein aneurysms, and
vena caval atresias were identied on CT as unanticipated
Anticoagulation
alone
22
Renal cell carcinoma, adrenal
sources and risk factors for iliofemoral DVT. Whether by
20.4 PRE-TREATMENT EVALUATION
Aer the diagnosis of acute DVT is established, all patients
should be placed on anticoagulation therapy immediately,
followed by leg elevation and leg compression.
anticoagulation and compression, ambulation is encouraged. Patients with iliofemoral DVT who are eligible for
anticoagulation and are ambulatory should be considered for thrombus removal. In patients with normal renal
function, a contrast-enhanced computed tomography
(CT) scan of the head, chest, abdomen, and pelvis is performed. Approximately 50% of these patients will have an
asymptomatic pulmonary embolus. Although such emboli
may not change the treatment plan, the value of establishing the diagnosis is oen not appreciated until 3–5 days
later when pleuritic chest pain develops in up to 25% of
asymptomatic PE patients.
of PE, physicians might suspect that the result of pleuritic
chest pain represents a “treatment failure” or an embolic
21
Without a previous diagnosis
18–20
Aer
CT or by duplex scan, imaging of the vena cava is important for assessing the degree of vena caval involvement with
thrombus. If oering catheter-based techniques, a vena
caval lter is recommended for patients with free-oating,
non-occlusive vena caval thrombus. If operating, either
proximal balloon occlusion of the inferior vena cava (IVC)
or caval ltration is appropriate in those patients with freeoating thrombus. e majority of patients with iliofemoral DVT do not require an IVC lter.
Patients with extensive venous thrombosis frequently
have a clinically obvious etiology (trauma), a known thrombophilia, or perhaps an occult cancer. However, those with
an unprovoked VTE frequently undergo a full hereditary
thrombophilia evaluation. Although we routinely performed a full battery of hereditary thrombophilia testing
earlier in our experience, we now know t hat it is unnecessary,
as the patient’s extensive DVT imparts such substantial risk
for future venous thromboembolic events that the risk conferred by the acute thrombotic event oen exceeds the risk
254 Catheter-directed thrombolysis, mechanical thrombectomy, and surgery
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of any identied hereditary thrombophilia.23 However, testing for an acquired thrombophilia is warranted. A serious
consequence of a negative thrombophilia evaluation is physician underestimation of future thrombotic risk. However,
thrombophilia testing is important in rst-degree female
relatives of childbearing potential, especially for factor V
Leiden, prothrombin, 20210 mutation, and antithrombin, as
these test results may impact future care during pregnancy.
Additionally, testing for an acquired thrombophilia, such as
antiphospholipid antibodies, is warranted.
Aer the extent of the disease has been established,
contraindications to either surgical or catheter-based
techniques should be objectively reviewed. In general, the
majority of patients with iliofemoral DVT should be oered
a strategy of thrombus removal. Individuals with occlusive thrombus of the common femoral vein have eectively
obliterated venous drainage from the lower extremity and
are subject to severe post-thrombotic morbidity. Although
most patients with acute DVT are treated as outpatients,
those with occlusion of the common femoral vein and/or
iliac vein should be hospitalized for an appropriate procedure designed to restore patency and provide unobstructed
venous drainage from their common femoral vein into their
vena cava. Our algorithm for the management of iliofemoral DVT is outlined in Figure 20.4.
20.5 INTRATHROMBUS CDT
e technique of CDT has evolved over the past several
years. Our preferred approach is generally through an
ultrasound-guided popliteal vein puncture with antegrade
passage of the infusion catheter. Patients who have distal
popliteal and tibial vein thrombosis are now approached
through ultrasound-guided posterior tibial vein access.
Adjunctive mechanical techniques are routinely used to
shorten the duration of lysis and speed clot resolution.
e dose and volume of the plasminogen activator that is
delivered has also evolved. Since the activation of brinbound plasminogen is not dose dependent, its exposure to
the plasminogen activator appears to be the most important factor. e volume of lytic solution has increased over
the years, with a decrease in the concentration (dose) of the
plasminogen activator. It is now our preference to increase
the volume of lytic infusion to 80–100 mL/hour. e larger
volume is intended to saturate the thrombus, exposing more
brin-bound plasminogen to the plasminogen activator.
One milligram of recombinant tissue plasminogen activator (rtPA) is delivered in 100 mL of saline. Phlebograms
are generally repeated at 12-hour intervals and are used to
monitor the success of lysis, reposition catheters, and perform other mechanical interventions. Following successful
(a)
(b)
(d)
(c)
(e) (f) (g)
Figure 20.3 A 65-year-old white man was referred with phlegmasia cerulea dolens of his left leg (a) 36 hours after major
abdominal laparotomy. Venous duplex demonstrated a clot in the posterior tibial veins extending to the external iliac vein.
A contrast-enhanced computed tomography scan of the chest, abdomen, and pelvis was performed and demonstrated
asymptomatic pulmonary emboli (b) and mediastinal (c), retroperitoneal (c, arrows), and pelvic lymphadenopathy (d,
arrows). The extensive thrombus is demonstrated by a catheter phlebogram of the femoral vein (e and f) and the silhouette of the calf thrombus (g) by the catheter in the posterior tibial vein at the ankle. (Continued)
20.5 Intrathrombus CDT 255
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(h)
(i)
Isolated
segment
between
balloons
(k) (l)
(j)
Ultrasound
transducers
(m) (n)
(o) (p)
(q)
Figure 20.3 (Continued) The bulk of the thrombus from the proximal popliteal vein to the common iliac vein was treated
with the Trellis catheter via an ultrasound-guided popliteal vein approach
(h). The clot in the posterior tibial and popliteal
veins was treated with the EKOS EndoWave system (i). Liquefied and fragmented thrombus resulting from isolated segmental pharmacomechanical thrombolysis was aspirated via the Trellis catheter (j). Segmental phlebography is performed
to check the results of treatment before moving to an adjacent thrombosed segment (k and l). Residual thrombus is
removed by rheolytic thrombectomy with the AngioJet, and the iliac vein compression is treated with a stent. A completion phlebogram shows patency of the calf, popliteal, femoral, and iliac veins, as well as supple valve cusps, thus suggesting that valve function persists (m –p). When catheter-based techniques are completed, a catheter is left in the popliteal
vein (or posterior tibial vein if distal access is used) for infusion of unfractionated heparin for 24 hours. The concept is
that the high concentration of heparin being infused into the target vein will increase its binding to residual thrombus,
endothelium, and subendothelial collagen, thereby reducing the risk of thrombosis. The patient was treated with systemic
chemotherapy for his underlying lymphoma. At 16 months
(q), the patient was asymptomatic, had no post-thrombotic
symptoms, maintained lower extremity venous patency with normal valve function, and fortunately had no evidence of
lymphoma recurrence.
256 Catheter-directed thrombolysis, mechanical thrombectomy, and surgery
Management of iliofemoral DVT
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Immediate anticoagulationRapid CT Scan with contrast
Leg elevation
Long leg compression
Ambulation permitted
• Head
• Chest
• Abdomen
• Pelvis
Patient physically active
Strategy of thrombus removalEvaluate vena cava
No Ye s
Pharmacomechanical
thrombolysis and/or
Catheter-directed
Anticoagulation
plus
compression
Figure 20.4 Suggested management protocol for patients with iliofemoral deep venous thrombosis. CT: computed
tomography; DVT: deep venous thrombosis.
Contraindication to thrombolysis
thrombolysis
Correct underlying venous lesion
• Correct iliac vein stenosis
• Arteriovenous fistula
• Catheter-directed anticoagulation
thrombolysis, the venous system is examined with completion phlebography. If an underlying stenosis exists, which
is frequently observed in the le common iliac vein where
it is compressed by the right common iliac artery, the vein
is balloon dilated and stented. e addition of intravascular
ultrasonography has improved the evaluation of iliac compression and the precision of stent deployment. Residual
areas of stenosis must be corrected to achieve long-term
success; otherwise, the patient faces a high risk of re-thrombosis. If a stent is used, it should be sized appropriately to
the projected normal diameter of the recipient vein.
20.6 PHARMACOMECHANICAL
THROMBOLYSIS
YesNo
Filter for free-
floating thrombus
Venous thrombectomy
treating thrombosed veins larger than the 6-mm hemodialysis gra. In an experimental model, Greenberg and asso-
25
ciates
evaluated mechanical, pharmacomechanical, and
pharmacologic thrombolysis. eir ndings are consistent
with anecdotal clinical observations as well as the results
reported by Kinney etal.24 ey reported that pulse-spray
mechanical thrombectomy was associated with the largest
number and greatest size of distal emboli. When urokinase
was added to the solution, the embolic particles diminished
in number and size and increased the speed of lysis and
reperfusion.
Vedantham etal.26 evaluated the eectiveness of mechanical thrombectomy alone and in combination with pharmacologic thrombolysis in 28 limbs of patients with acute DVT.
ey evaluated multiple devices, including the Amplatz
e adjunctive use of mechanical techniques is rapidly
becoming the standard for catheter-based management of
extensive venous thrombosis.
24–30
Percutaneous mechanical thrombectomy alone is less successful than CDT, and is
associated with unacceptably high pulmonary embolic complications. A prospective evaluation of pulse-spray pharmacomechanical thrombolysis of thrombosed hemodialysis
gras found that PE occurred in 18% of patients treated
with a plasminogen activator pulse-spray solution versus
64% of patients treated with a heparinized saline pulsespray solution (P = 0.04).
24
Since thrombosed hemodialysis
gras are in direct communication with the venous circulation, they can be considered similar to proximal veins with
acute DVT. Observations would likely be magnied when
(ev3, Inc.), AngioJet (Possis Medical), Trerotola (Arrow
International), and Oasis (Boston Scientic/Medi-tech)
catheters. Venography was performed at each step of the
procedure. A total of 26% of the thrombus was removed by
mechanical thrombectomy alone, whereas adding a plasminogen activator solution to the mechanical technique (pharmacomechanical) removed 82% of the thrombus.
27
Lin et al.
reported their 8-year experience with pharmacomechanical thrombolysis using a rheolytic thrombectomy catheter. Of their 98 patients, 46 received CDT alone
and 52 underwent pharmacomechanical thrombolysis.
Pharmacomechanical thrombolysis with the AngioJet catheter (Boston Scientic) was associated with signicantly
fewer phlebograms, shorter intensive care unit stays, shorter
20.7 Operative venous thrombectomy 257
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hospital stays, and fewer blood transfusions. Bleeding complications were not dierent between the two groups. A
smaller patient group treated by rheolytic thrombectomy
was reported by Kasirajan et al.,28 who demonstrated that
mechanical thrombectomy alone was less eective than
combined pharmacomechanical thrombolysis.
CDT alone was associated with the slowest reperfusion
but the fewest distal emboli. In general, mechanical thrombectomy alone most oen is inadequate. Although rheolytic
pharmacomechanical techniques have been helpful in many
patients for clearing a dicult lesion, hemolytic complications are common, and occasionally result in anemia and
renal dysfunction. A device designed for isolated segmental and controlled pharmacomechanical thrombolysis is
the Trellis catheter (Covidien). is hybrid catheter isolates
the thrombosed vein segment between two occluding balloons aer the introduction of a dispersion wire. A lytic
agent is infused into the thrombus between the occluding
balloons. e intervening catheter sha assumes a spiral
conguration, which is then motor-activated to rotate at
3500 rpm. Aer 15–20 minutes, the liqueed thrombus and
remaining fragments can be aspirated through the sheath.
Phlebographic evaluation was performed before moving on to treat additional thrombosed vein segments. e
advantages of such a device include its ability to incorporate mechanical and pharmacological therapies, and to treat
patients who have traditional contraindications to higher
doses of thrombolytic agents, as much of the lytic infusate
can be aspirated. e clot is more rapidly lysed and treatment times are signicantly shortened. Martinez-Trabal
showed that patients treated with isolated segmental pharmacomechanical thrombolysis had a signicantly more
rapid lysis time, with a reduction in the dose of plasminogen
activator.
29,30
Unfortunately, the Trellis catheter is no longer
available.
An adjunct to CDT is the incorporation of ultrasound
transducers into the infusion catheter. Ultrasound waves
generated during infusion of the plasminogen activator
increase the surface area of brin and speed lysis. Several
reports have emerged indicating that an infusion catheter
with ultrasound transducers built into the infusion end of
the catheter can be used to accelerate thrombolysis.
31–33
In
vitro studies have demonstrated that ultrasound enhances
the brinolytic activity of tissue plasminogen activators
32,34,35
(t-PA).
e potential mechanism for augmented clot
lysis has been extrapolated from in vitro studies showing that ultrasound produces clot fragmentation in the
presence of t-PA and, consequently, more t-PA binds to
brin binding sites because of the larger available surface
36,37
area.
e concept of a transducer tip catheter that delivers a brinolytic drug in combination with high-frequency,
low-intensity ultrasound has been studied by Engelberger
etal.38 In a single-center randomized and controlled trial
38
of patients with PE, Engelberger etal.
showed that xeddose, low-intensity ultrasound-assisted thrombolysis was a
safe and eective treatment for PE. ey reported that their
experience with ultrasound-accelerated thrombolysis for
iliofemoral DVT followed by routine stenting of residual
stenosis resulted in low bleeding rates, high patency rates,
and a low rate of PTS.
39
e same authors investigated the added benet of
ultrasound to CDT in patients with iliofemoral DVT. ey
randomized 48 patients with acute iliofemoral DVT to
receive CDT or ultrasound-accelerated thrombolysis.40 All
patients had the ultrasound infusion catheter inserted into
the thrombosed iliac veins. Only those randomized to the
ultrasound-accelerated group had the ultrasound activated.
Aer their target of 15 hours of treatment, the authors
found that patients had 54% and 55% thrombus load reductions with CDT and ultrasound-accelerated thrombolysis,
respectively. ere were no dierences between treatment
groups in any of the other outcomes evaluated.
e patient with phlegmasia cerulea dolens described in
Figure 20.3 illustrates the advantage of using isolated seg-
mental pharmacomechanical thrombolysis to potentially
shorten treatment duration and limit exposure to the thrombolytic agent, thereby maximizing the chance of a safe and
successful outcome. As this patient was treated before the
study published by Engelberger etal.,40 we cannot conclude
that ultrasound assisted thrombolysis (USAT) achieved better results than would have been achieved with CDT by the
drip technique. As technology continues to improve, lytic
infusion times will shorten, more patients will be oered a
treatment strategy that includes thrombus removal (Figure
20.4), and many more patients will be spared their other-
wise certain post-thrombotic morbidity.
20.7 OPERATIVE VENOUS
THROMBECTOMY
Although operative venous thrombectomy is infrequently
required because of the increased safety and eectiveness of
CDT for IFDVT, it remains a valuable treatment option in
selected patients. Such patients include those with multiple
trauma, and active bleeding in those at high risk for bleeding into a critical site (intracranial and intraocular). What
follows is a description of our current technique.
General anesthesia is usually recommended for patients
undergoing operative venous thrombectomy. A longitudinal inguinal incision exposes the common femoral, femoral, saphenofemoral junction, and profunda femoris vein or
veins (Figure 20.5a). A longitudinal venotomy of the common femoral vein is recommended to ensure access to the
origin of the saphenous and profunda femoris branches. If
infrainguinal thrombus is present, the leg is elevated and
compressed with a tightly wrapped rubber bandage, the
foot is dorsiexed, and the calf and thigh are squeezed. If
all infrainguinal thrombus is removed, which is clinically
evident when it occurs, balloon thrombectomy of the iliofemoral venous system is performed.
If the infrainguinal thrombus persists and a guidewire
can be advanced distally, an infrainguinal thrombectomy
can be performed using an over-the-wire balloon thrombectomy catheter. If a guidewire cannot be passed through
258 Catheter-directed thrombolysis, mechanical thrombectomy, and surgery
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the infraingual valves, a cut-down is performed to expose
the distal posterior tibial vein. A No. 3 Fogarty catheter is
advanced from the distal posterior tibial vein to and through
the common femoral venotomy. e Silastic stem of an
intravenous catheter (12–14 gauge) is amputated from its
hub and slid halfway onto the balloon catheter. Another balloon catheter (No. 4 Fogarty) is placed in the opposite end of
the Silastic sheath (Figure 20.5a). Pressure is applied to the
two balloons by a single operating surgeon to ensure that the
catheters remain secure inside the sheath. e No. 4 balloon
catheter is guided distally through the thrombosed venous
valves and clotted veins (Figure 20.5b) to the level of the
posterior tibial venotomy (Figure 20.5c). Alternatively, if an
over-the-wire balloon thrombectomy catheter is available, a
guidewire can be passed proximally from the distal posterior
tibial vein and the infrainguinal thrombectomy performed,
with passage repeated as necessary (Figures 20.5d and e).
Aer infrainguinal balloon catheter thrombectomy, the
infrainguinal venous system is ushed by placing a large red
rubber catheter into the proximal posterior tibial vein and
(a)
Tip of balloon catheter
Silastic sheath
vigorously ushing with a heparin–saline solution, using
a bulb syringe to hydraulically force residual thrombus
from the deep venous system (Figure 20.5f). Frequently, an
impressive amount of additional thrombus will be retrieved
with this maneuver. Once the infrainguinal venous system
is adequately cleared, a vascular clamp is applied below the
femoral venotomy and the infrainguinal venous system is
lled with dilute plasminogen activator solution consisting
of approximately 4–6 mg of rtPA in 200 mL of saline. e
plasminogen activator solution remains in the infrainguinal veins for the remainder of the procedure. is amount
of local rtPA will bind to brin-bound plasminogen in the
residual thrombus and promote further clot dissolution;
however, this dose will not cause a systemic lytic response
due to circulating plasminogen activator and plasmin
inhibitors. If the infrainguinal venous thrombectomy is not
successful because of older thrombus or chronic disease,
the femoral vein is ligated and divided below the profunda
femoris vein. Patency of the profunda is ensured by direct
thrombectomy if necessary.
(c)
(b)
(e)
(d)
Figure 20.5 Surgical repair of venous thrombosis. (a) Longitudinal inguinal incision to expose the common femo-
ral vein, femoral vein, saphenofemoral junction, and profunda femoris vein. (b and c) The balloon catheter is guided
distally through the thrombosed venous valves and clotted veins to the level of the posterior tibial venotomy. (d and
e) Performance of infrainguinal venous thrombectomy, with passage of the balloon catheter repeated as necessary.
(Continued)
(f) (g)
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20.7 Operative venous thrombectomy 259
(h)
(i)
Figure 20.5 (Continued) (f) After infrainguinal balloon catheter thrombectomy, flushing of the infrainguinal venous system
with a heparin–saline solution is performed by placing a large red rubber catheter into the proximal posterior tibial vein
and flushing vigorously with a bulb syringe. After flushing is complete, 250–300 cc of saline with 3–4 mg rtPA is infused
into the deep venous system after the clamp is reapplied to the distal common femoral vein (CFV). The proximal thrombectomy is then performed. (g) Ilio-caval thrombectomy can be performed with a protective balloon catheter inflated
above the caval thrombus, if it exists, as an alternative to vena caval filtration. A large venous thrombectomy catheter is
used, with an 8–10-Fr balloon. (h) Placement of a piece of polytetrafluoroethylene or Silastic wrap around the saphenous
arteriovenous fistula. A large, permanent monofilament suture is looped and clipped with approximately 2 cm left in the
subcutaneous tissue. This serves to limit dilation of the arteriovenous fistula and is also a guide for dissection should
surgical disconnection of the arteriovenous fistula become necessary.
(i) Placement of a small infusion catheter (pediatric
feeding tube) into the wound via a separate stab incision in the skin. It is inserted and fixed in the proximal posterior tibial
vein for infusion of unfractionated heparin directly into the thombectomized vein.
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