Keywords
deep vein thrombosis - mechanical thrombectomy - Paget–Schroetter's syndrome
Introduction
Upper extremity deep vein thrombosis (UEDVT) has an estimated annual incidence of
1 per 10,000 people and accounts for up to 10% of all deep vein thrombosis (DVT) cases.[1]
[2]
[3] Recent increases in the use of central venous catheters, peripherally inserted central
catheters, and pacemakers have led to a steady rise in the incidence of UEDVT.[3]
[4] Indwelling central venous catheter use has been associated with a 7-fold to 14-fold
increase in the likelihood of developing a secondary or provoked UEDVT, constituting
the majority of UEDVT cases.[5]
[6] Although primary UEDVT or Paget–Schroetter's syndrome (PSS) is less common, these
cases can be more severe and may require decompression surgery to alleviate the underlying
anatomical cause of thrombosis.[1]
[3] Complications of UEDVT are similar to those observed with lower extremity DVT and
include pulmonary embolism, rethrombosis, and postthrombotic syndrome.[7]
[8]
While symptoms of UEDVT can often be effectively managed with anticoagulation over
time,[9] rapid restoration of symptoms is preferred. The CHEST guidelines suggest considering
catheter-directed thrombolysis for patients with severe symptoms, thrombus involving
most of the subclavian and axillary veins, symptoms <14 days, good functional status,
life expectancy ≥1 year, and low bleeding risk.[9] Unfortunately, there are few studies assessing endovascular treatments in UEDVT.
Retrospective studies have reported effective restoration of patency in UEDVT patients
treated with catheter-directed thrombolysis, although its use is associated with increased
bleeding risks.[9]
[10]
[11]
[12] Positive outcomes have been reported with aspiration thrombectomy for the treatment
of primary UEDVT.[2]
[13] To our knowledge, no study has assessed standalone mechanical thrombectomy techniques
for UEDVT, which we aimed to address with this study.
Materials and Methods
Research Ethics Standards Compliance
This study obtained Institutional Review Board approval under the exempt process.
For this type of study, formal research ethics committee review, informed consent,
or consent for publication are not required. The research was performed according
to the Declaration of Helsinki principles.
Study Design
This is a single-center retrospective chart review of patients who underwent mechanical
thrombectomy for the treatment of UEDVT. All patients who received treatment with
the ClotTriever system (Inari Medical, Irvine, California, United States) for UEDVT
between October 3, 2019, and August 7, 2023, were included, irrespective of UEDVT
etiology, age, or health status.
Study Outcomes
The primary outcome was technical success, defined as ≥75% of thrombus removal. Technical
success was determined by an interventional radiologist who reviewed the preprocedural
and postprocedural venograms for each patient. Intraprocedural adverse events are
reported. Secondary outcomes included the ability to complete the procedure in a single
session, the length of postprocedural hospital stay, and the proportion of patients
who remained free from death, pulmonary embolism, and rethrombosis during follow-up.
The follow-up period was defined as the duration between the procedure date and the
date of the last follow-up appointment.
Study Device and Procedure
The ClotTriever system is a single-use, over-the-wire system comprising a sheath and
thrombectomy catheter ([Fig. 1]). This device is U.S. Food and Drug Administration cleared and CE marked for treating
lower extremity DVT.[14]
[15]
Fig. 1 A 40-year-old woman presenting to the emergency room with swelling, numbness, and
discoloration of the left upper extremity following septoplasty and left tympanostomy
tube placement. (A) Preprocedural venographic fluoroscopy demonstrating left upper extremity brachial
vein deep venous thrombosis extending into the left jugular vein. (B) Postprocedural venographic imaging demonstrating resolution of thrombus. (C) Image of a deployed device within the upper extremity. (D) Depiction of components of the ClotTriever system (Copyright of Inari Medical, Irvine,
California, United States).
Venous access was obtained with a guidewire. Basilic vein access was preferred given
the theoretical risk of injury to the adjacent nerve or artery with brachial vein
access. After the initial venogram, dilation of the venotomy site was performed, followed
by the introduction of the device sheath and deployment of the mesh funnel.
After the introduction of the ClotTriever catheter via the sheath, the coring element
and collection bag were deployed. The catheter was retracted through the thrombosed
venous segment into the funnel of the sheath, and the plunger was then used to collapse
the coring element and collection bag prior to the removal of the catheter with the
captured thrombus. Additional thrombectomy passes were repeated until the thrombus
was removed.
Statistical Methods
Baseline and procedural characteristics, periprocedural outcomes, and outcomes through
follow-up are expressed as median values with interquartile range (IQR) or number
of observations with proportion of the total population or procedure number. Data
were analyzed using Microsoft Excel for Microsoft 365 MSO (version 2206).
Results
Baseline Characteristics
A total of 14 patients with UEDVT who underwent mechanical thrombectomy were included
in this analysis. Baseline characteristics for patients are shown in [Table 1]. Four patients (28.6%) had a medical history of prior DVT. Two patients presented
with concomitant pulmonary embolism diagnosed prior to intervention.
Table 1
Patient characteristics at baseline
|
Characteristics
|
Patients (N = 14)
Median (IQR) or n (%)
|
|
Age, y
|
44 (33.5, 57)
|
|
Female sex
|
7 (50)
|
|
Medical history
|
|
Malignancy
|
3 (21.4)
|
|
Hypercoagulable disorder
|
2 (14.3)
|
|
Indwelling UE lines
|
6 (42.9)
|
|
Contraindication to thrombolytics
|
2 (14.3)
|
|
Diagnosis
|
|
Primary UEDVT
|
8 (57.1)
|
|
Secondary UEDVT
|
6 (42.9)
|
|
At presentation
|
|
Receiving anticoagulation
|
3 (21.4)
|
|
Limb ischemia
|
0 (0)
|
|
Limb edema
|
14 (100)
|
|
Thrombus location[a]
|
|
Subclavian
|
13 (92.9)
|
|
Axillary
|
10 (71.4)
|
|
Brachial
|
4 (28.6)
|
|
Basilic
|
5 (35.7)
|
|
Brachiocephalic
|
4 (28.6)
|
|
Cephalic
|
1 (7.1)
|
|
Laterality
|
|
Right
|
6 (42.9)
|
|
Left
|
8 (57.1)
|
Abbreviations: IQR, interquartile range; UE, upper extremity; UEDVT, upper extremity
deep vein thrombosis.
Note: Values are median (IQR) or n (%).
a Subcategories are not mutually exclusive.
Most patients (85.7%; n = 12) had thrombus in two or more vein segments. Thrombus most often involved the
subclavian vein and axillary vein (71.4%). The median reported symptom duration was
5 days (IQR: 4, 12). Twelve patients had acute symptoms (≤14 days), and the remaining
two patients had symptoms persisting for 21 days and 60 days prior to the procedure.
Three patients (21.4%) received previous treatment for their current UEDVT, one with
catheter-directed thrombolysis at another facility, another using aspiration thrombectomy
with the Indigo Cat8 system (Penumbra, Alameda, California, United States) during
the same procedure before the decision was made to switch to the study device due
to significant residual thrombus, and the third with a 16-Fr Penumbra device and an
8-Fr AngioJet device (Boston Scientific, Marlborough, Massachusetts, United States)
followed by 10-mm and 12-mm balloon venoplasties.
Procedural Characteristics
All procedures were completed under conscious sedation. Basilic vein access was obtained
in all cases. Twelve procedures involved adjunctive venoplasty ([Table 2]). Stent placement was required in two patients who developed brachiocephalic DVT
following placement of a tunneled dialysis catheter. In one case, stent placement
was performed to address anticipated central vein stenosis following thrombectomy
given the patient's history of end-stage renal disease and hemodialysis dependence.
In the second patient, the stent was placed due to recoil of the subclavian vein immediately
following venoplasty. Adjunctive thrombolytics were not used in any case, and no patients
required blood transfusion.
Table 2
Procedural characteristics
|
Procedural characteristics
|
All procedures (n = 14)
|
Primary UEDVT (n = 8)
|
Secondary UEDVT (n = 6)
|
|
Fluoroscopy duration (IQR), min
|
13.4 (11.4, 16.4)
|
12.5 (10.9, 14.7)
|
17.4 (12.5, 22)
|
|
Venoplasty
|
12 (85.7)
|
8 (100)
|
4 (66.7)
|
|
10 mm
|
7 (50)
|
5 (62.5)
|
2 (33.3)
|
|
12 mm
|
5 (37.5)
|
2 (25)
|
3 (50)
|
|
14 mm
|
5 (37.5)
|
3 (37.5)
|
2 (33.3)
|
Abbreviations: IQR, interquartile range; UEDVT, upper extremity deep vein thrombosis.
Note: Values are median (IQR) or n (%).
Procedural Outcomes
Technical success was achieved in all mechanical thrombectomy procedures, with ≥75%
of thrombus removal in all targeted venous segments. Images from a representative
example case are shown in [Fig. 1]. There were no serious adverse events during the procedure. One patient had minor
bleeding from the access site, which resolved with manual compression, and follow-up
hemoglobin levels remained unchanged.
Secondary Outcomes
All procedures were completed in a single session, and the median length of postprocedural
hospital stay was 2 days (IQR: 1, 3). All patients were discharged on anticoagulants
except one who was discharged on dual antiplatelet therapy. Seven patients were discharged
with instructions to use compression therapy. After a median follow-up of 88 days,
there were no deaths, and 71.4% of patients had not experienced a pulmonary embolism
or rethrombosis.
Four patients experienced rethrombosis, three of whom had underlying PSS. Of the three
rethrombosed patients with PSS, one experienced rethrombosis 3 days after the index
procedure. Reintervention with the study device was performed with surgical decompression
5 days following the index procedure. This patient then experienced rethrombosis event
28 days after rib resection which was treated with an extended course of anticoagulation.
The second patient with PSS had a rethrombosis event 15 days after the index procedure.
This patient then experienced a pulmonary embolism 5 days later while holding apixaban
for rib resection which was eventually performed 184 days after the index procedure.
The patient was followed up for an additional 111 days without incident. A new UEDVT
was noted by ultrasound 33 days after the index procedure in the third patient with
PSS and rethrombosis, who had received surgical decompression on the same day as the
index procedure. Repeat thrombectomy was not performed. The final patient experienced
rethrombosis of the superior vena cava (SVC) secondary to hemorrhagic shock and bacteremia
80 days after the index procedure and did not receive repeat thrombectomy due to collateralization
of the SVC.
Surgical Decompression
Five of the eight patients with primary UEDVT due to PSS went on to receive surgical
decompression during the follow-up period at a median of 33 days (IQR: 5, 61) after
the index procedure date. Of these five patients, two had recurrence of UEDVT following
surgical decompression at postoperative days 28 and 32. Neither patient underwent
any additional procedure or surgery, and both were managed with oral anticoagulant
therapy. One patient had a total resolution of UEDVT, while the other went on to develop
a chronic, partially occlusive subclavian thrombus. Three patients with primary UEDVT
due to PSS who underwent surgery did not experience recurrence of UEDVT during the
subsequent follow-up period over a median 358 days (IQR: 235, 773). Of the three patients
with primary UEDVT due to PSS who did not receive surgical decompression, two initially
had surgical decompression scheduled but instead elected for long-term anticoagulation,
and the final patient was lost to follow-up.
Discussion
This analysis assessed mechanical thrombectomy for the treatment of UEDVT in a heterogeneous
population without excluding patients based on UEDVT etiology, thrombus location,
or symptom duration. While the sample size, lack of a comparator arm, and retrospective
nature of the study limit its conclusiveness, the data suggest standalone mechanical
thrombectomy represents a safe and effective option for UEDVT. This analysis adds
to the scarce information on interventional treatment of UEDVT.
While endovascular interventions play an important role in the acute management of
UEDVT, surgical resolution of the underlying extrinsic osseous venous compression
is most crucial in the definitive management of patients with PSS. Two of the four
rethrombosis events occurred in patients burdened with significant residual stenosis
secondary to osseous compression while awaiting surgical decompression. Accordingly,
the documented cases of rethrombosis are favored secondary to delay in operative intervention.
The mechanical thrombectomy device used in this series is regarded as primarily sized
for use in the lower extremities. In all cases, the 13-Fr sheath was employed. Yet,
the device size did not present any significant impediment to effective upper extremity
use, and there was no clinical evidence of vessel trauma or venous valvular insufficiency.
In many cases, the peripheral basilic venous segment accessed was >6 mm.
When specifically compared with thrombolysis, mechanical thrombectomy demonstrates
several advantages. Bleeding risk is reduced by virtue of eliminating the use of thrombolytics.
Additionally, the lack of thrombolytic infusion obviates the need for intensive care
unit admission, potentially decreasing hospital resource utilization.
It is well recognized that thrombus chronicity affects efficacy of interventional
treatments for DVT. While symptom duration is often used to estimate thrombus age,
it has been shown not to be a wholly reliable indicator,[16] and thrombus in patients with acute symptoms often has a mixture of acute and chronic
characteristics upon assessment following mechanical thrombectomy.[17]
[18] Mechanical thrombectomy with the study device has demonstrated a high rate of success
at removing both acute and chronic components,[14]
[19] while thrombolysis has been shown to be less effective for more aged thrombus.[16] This finding is demonstrated well in this study where technically successful mechanical
thrombectomy procedures were completed after a previous therapy for the index UEDVT
had failed, including one patient with prior failed catheter-directed thrombolysis
and two patients after failed aspiration thrombectomy.
Conclusion
In conclusion, results from this study suggest mechanical thrombectomy provides effective
thrombus removal and can be safely performed in patients with UEDVT. Procedures were
completed in a single session without the use of adjunctive thrombolytics, and 100%
technical success was achieved. There were no major bleeding complications or serious
adverse events, and the majority of patients remained free from complications during
available follow-up. Additional research in a larger population and randomized controlled
trials is needed to further elucidate long-term outcomes and define the role of mechanical
thrombectomy in UEDVT treatment guidelines.
