Deep vein thrombosis (DVT) has long been recognized as a major medical problem that can lead to life-threatening complications such as pulmonary embolism and postthrombotic syndrome. The treatment of DVT has evolved over the centuries, reflecting advances in medical technology and a deeper understanding of vascular pathophysiology. Among these advances, thrombectomy has been a pivotal development in the management of patients who do not respond to conventional anticoagulation therapy.

The concept of physically removing a thrombus from a vessel dates back to the early 20th century. Before the advent of modern imaging and interventional techniques, early surgical approaches to thrombectomy were simple but associated with many complications. Anticoagulation therapy, first described in the 1950s, was one of the first attempts to directly address DVT. However, this approach was invasive, carried a high morbidity rate, and was reserved primarily for the most severe cases.

The field began to change dramatically in the late 20th century with the introduction of catheter-based techniques. Catheter-directed thrombolysis (CDT), introduced in the 1990s, allowed for local delivery of clot-dissolving agents, thereby reducing the risks associated with systemic thrombolysis. However, CDT alone was not always sufficient to remove large or chronic clots. These limitations prompted the development of mechanical thrombectomy devices in the early 2000s as an adjunctive or independent option for more efficient clot removal. One device developed during this period was pharmaco-mechanical thrombolysis.

Advances in imaging techniques such as venography and intravascular ultrasound further improved the precision and safety of thrombectomy. These innovations were coupled with an increased awareness of the importance of early and aggressive intervention, particularly in cases of deep vein thrombosis, including the iliofemoral vein, where the risk of long-term complications is highest.

Modern treatment of DVT emphasizes isolated pharmacomechanical thrombectomy as a minimally invasive and effective treatment option. This technology focuses on rapidly removing clots in selected patient groups while reducing the risk of complications such as bleeding.

In the case of catheter-directed intervention devices currently available, clots are removed in various ways as shown in Table 1.

Table 1 . Catheter-directed interventions.

Working mechanism	Machine examples
Mechanical thrombectomy	Clotriever
Aspiration thrombectomy	AngioVac system
	Indigo aspirational system
Rotational thrombectomy	Cleaner rotational thrombectomy system
Rheolytic thrombectomy	AngioJet thrombectomy catheter
	JETi hydrohynamic thrombectomy system
Ultrasound-enhanced thrombolysis	EKoSonic endovascular system

Currently, there are three types of thrombectomy devices available in Korea: Angiojet, Cleaner, and Aspirec.

Angiojet is a pharmaco-mechanical thrombectomy device that uses a high-velocity saline jet to break up and aspirate clots while simultaneously delivering clot-dissolving agents directly to the clot site.

A 2022 multicenter study reported that Angiojet successfully removed clots in more than 85% of patients and minimized residual clot thickening. The combination of mechanical action and dissolving agent delivery shortened the procedure time compared to conventional CDT. However, it was noted that the high-pressure jet may slightly increase the risk of bradycardia during the procedure [1].

A 2021 meta-analysis reported that Angiojet resulted in significantly less post-thrombotic syndrome (PTS) than CDT. In addition, the same study confirmed that the treatment duration was much shorter and the drug dose used was statistically significantly lower [2].

Angiojet is particularly effective for extensive clots such as those in the femoral and iliac veins and can be used in situations where rapid clot removal is required.

Cleaner is a device that mechanically crushes and removes blood clots using a rotating wire, and is suitable for small to medium-sized veins. This device may be beneficial for patients at high risk of bleeding by minimizing the use of thrombolytics.

A study conducted in 2015 on 16 subjects reported a successful rate of 87.5% and no signs of pulmonary embolus [3].

Aspirex combines a rotational mechanism with suction to break up and remove clots, and works effectively without the use of clot-dissolving agents.

A single-session percutaneous mechanical thrombectomy study was conducted in 2020, which evaluated the safety, efficacy, and mid-term outcomes of single-session percutaneous mechanical thrombectomy using the Aspirex ^®S device. The study reported a 100% clot removal success rate and an 86.7% secondary patency rate, with no major complications [4].

In addition, the P-MAX study, published in 2022, is a post-marketing follow-up study that evaluated the safety and efficacy of DVT treatment using the Aspirex ^®S device. The study reported a 97.5% procedural success rate and a 77.9% primary patency rate at 24 months of follow-up. In addition, the Aspirex ^®S device was identified as an effective treatment option in patients with acute and subacute DVT [5]. These studies suggest that the Aspirex ^®S device is an effective and safe option for the treatment of DVT. In particular, it may be evaluated as a suitable treatment option for patients who are contraindicated for the use of clot-dissolving agents. Since it does not require the use of clot-dissolving agents, the risk of bleeding is reduced, making it an appropriate option for patients who are contraindicated for the use of clot-dissolving agents.

The Penumbra Indigo system is a suction-type thrombectomy device that can continuously remove clots using a vacuum suction method.

The Penumbra Indigo system has shown high clot removal rates in cases of acute femoral and iliac DVT, and patients experienced rapid symptom relief.

A study reported in 2019 was conducted on 10 patients, and the technical success rate was reported to be 60% [6].

In addition, the EXTRACT-PE study published in 2021 is a multicenter prospective study evaluating the safety and efficacy of treating acute pulmonary embolism (PE) using the Penumbra Indigo system. This study enrolled 119 patients, and showed significant improvement with a mean decrease of 0.43 in the right ventricle to left ventricle ratio after 48 hours. In addition, the incidence of major adverse events was low at 1.7% [7].

The ongoing BOLT study is a multicenter study evaluating the safety and efficacy of treating DVT using the Penumbra Indigo system. The study began on September 30, 2021, and is expected to be completed in February 2027. Interim results to date have not yet been published.

These studies suggest that the Penumbra Indigo system is an effective and safe option for the treatment of DVT and PE. In particular, it is applicable to a wide range of vessel sizes and is easy to use in complex anatomy, making it a useful treatment option for patients.

The Penumbra Indigo system has an adjustable tip, making it easy to use in complex anatomy, and has excellent safety characteristics, such as a low incidence of vessel damage or residual thrombosis.

Clotreiver is a dedicated venous thrombectomy device that can remove large clots in a single procedure without clot dissolution. It uses an expandable nitinol-based capture device that moves along the vessel wall to separate and capture clots from the vessel and then remove them from the vessel.

The CLOUT registry, published in 2023, is a multicenter prospective study that evaluated the safety and efficacy of DVT treatment using the ClotTriever system. The study enrolled 500 patients and showed a clot removal rate of more than 75% at 6 months of follow-up. In addition, the incidence of major adverse events was low at 1.7% [8].

It showed high clot removal rates and symptom improvement in both acute and subacute DVT patients, and showed excellent results in long-term follow-up. In particular, it is considered a suitable treatment for patients for whom clot dissolution is contraindicated.

Thrombectomy is currently not the first-line treatment for all DVT patients. Compared with anticoagulation therapy, which has become the standard treatment, thrombectomy has proven superiority only in certain conditions, and has limitations in terms of cost, procedure-related risks, and prevention of long-term complications. However, the technology of thrombectomy is rapidly developing, and this development opens the possibility that thrombectomy will become the first-line treatment for selected patients in the future.

The future research and development directions are as follows:

1. Development of patient-tailored treatment strategies

Studies are needed to clearly define the cases in which thrombectomy is most appropriate based on the location, size, degree of chronicity of the thrombus, and individual risk factors of the patient.

2. Evidence-based approach through comparative studies

Large-scale randomized controlled trials that directly compare existing anticoagulation therapy with thrombectomy are needed. This will allow for evaluation of the superiority of thrombectomy in terms of long-term survival, prevention of complications, and improvement in the patient’s quality of life.

3. Continuous improvement of technology

The design of thrombectomy devices should be improved to increase the safety of the procedure and to expand the indications for use in a wider range of patient populations.

Thrombectomy is considered a powerful treatment tool in certain situations in patients with acute DVT. However, it has the potential to evolve into a first-line treatment applicable to a wider range of patients in the future. This potential will become a reality when it is demonstrated that it outperforms existing treatments in terms of prevention of long-term complications, rapid symptom relief, and improvement in quality of life.

The author declares no conflicts of interest.

This report was presented under the title of thrombectomy device new update, at the 47th annual academic meeting of The Korean Society for Phlebology.