**5. Combination mechanical and pharmacological thrombolysis catheters**

These devices combine both mechanical dissolution and pharmacological thrombolysis to the clot. The devices include EKOS endowave system, Trellis peripheral infusion system and the Possis Angiojet system. The EKOS system is the newest of the devices. EKOS uses ultrasonic agitation of the clot with drug infusion to speed the clot lysis. This helps clear the large bulky clot typically seen in the venous system. (Fig 2) (Fig 3) The large clot burden in the legs and pulmonary arteries are ideal for this device. Theoretically, there is less drug used and less infusion time resulting in less intensive care monitoring and lessening the cost of the hospital stay. (Fig 4)

Various areas may be treated within the venous distribution. The treatable areas include extremity veins, superior venacava, portal vein, inferior venacava, mesenteric veins, renal veins, and pulmonary veins. These cases present in various different clinical scenarios based on acuity and severity of symptoms. Extremity swelling, pain and positive Doppler duplex venous ultrasound are the typical presenting clinical picture. For other venous thromboses, more severe clinical sequela are evident in the setting of portal vein and mesenteric vein thromboses. If not treated quickly, these can present with severe bowel compromise requiring emergent surgery. Computed tomographic angiographic images usually confirm the findings. Massive pulmonary emboli can also present as cardiovascular collapse if not treated emergently. Various scenarios from life threatening entities to outpatient treatments

There are many devices now on the market to treat vascular thromboses and in particular venous thrombosis. Various types of endovascular devices are now on the market for venous thrombolysis. These include the Unifuse and Speed-Lyser infusion catheters (Angiodynamics, Queensbury, New York), Possis AngioJet Ultra thrombectomy system (Medrad, Minneapolis, Minnesota), EKOS endowave endovascular system (EKOS Corporation, Bothell, WA), Trellis peripheral infusion system (Bacchus Vascular, Santa Clara, CA), Spectranetics Turbo Elite Laser Ablation catheter (Spectranetics, Colorado Springs, CO) and a pure aspiration catheter

There are three different types of catheter systems. One catheter is just used for thrombolytic drug infusion (Speed-Lyser and Uni-Fuse). The second sets of catheter systems are combined devices using both mechanical and pharmacological thrombolysis (EKOS endowave, Possis angiojet, and Trellis thrombectomy) The third set of devices use only mechanical thrombectomy (Possis angiojet, Spectranectics laser ablation and Pronto extraction catheter).

These catheters systems are the original type for thrombolysis. The Uni fuse is a single catheter system with multiple side holes throughout its infusion length. (Fig 1) They infuse drug directly into the clot and allow the drug to act directly on the thrombus intraluminally. The catheters come in various sizes and lengths. The speed lyser catheter is unique short device with only 15 and 20cm lengths. This device is designed to be used during fistulalysis procedures for dialysis patients. Both catheter systems are excellent for clot dissolution due

**5. Combination mechanical and pharmacological thrombolysis catheters** 

These devices combine both mechanical dissolution and pharmacological thrombolysis to the clot. The devices include EKOS endowave system, Trellis peripheral infusion system and the Possis Angiojet system. The EKOS system is the newest of the devices. EKOS uses ultrasonic agitation of the clot with drug infusion to speed the clot lysis. This helps clear the large bulky clot typically seen in the venous system. (Fig 2) (Fig 3) The large clot burden in the legs and pulmonary arteries are ideal for this device. Theoretically, there is less drug used and less infusion time resulting in less intensive care monitoring and lessening the cost

called the Pronto Extraction catheter (Vascular Solutions, Minneapolis, MN).

can be approached with endovascular means.

**4. Thrombolysis/Infusion catheters** 

of the hospital stay. (Fig 4)

to their ease of use and ability to use any drug combination.

**3. Available devices** 

Fig. 1. 64 y/o female with left leg swelling and pain and a positive U/S for DVT A) Extensive DVT Left SFV extending into iliac system B) EKOS Endowave combination thrombolysis catheter in place with TNK infusion overnight C) Widely patent ilio-femoral venous system following thrombolysis

Current Endovascular Treatments for Venous Thrombosis 83

A)

B)

C)

A) Extensive ilio-caval thrombus B) and C) Kissing EKOS catheters placed simultaneously with TNK initiated for overnight infusion now with widely patent iliac veins and venacava

Fig. 3. 54 y/o male with bilateral leg DVT and ilio-caval DVT

on final images

Fig. 2. 39 y/o female with May-Thurner Syndrome presents with left leg swelling, pain and + DVT A) Extensive DVT left leg B) Pure thrombolytic therapy performed with Unifuse catheter system and TNK for overnight infusion C) Uncovered irregular stenosis Left iliac vein D) Balloon venoplasty performed with improved appearance but residual stenosis remains E) Iliac venous stent placed now with widely patent venous flow through iliac veins

A) B)

C) D)

Fig. 2. 39 y/o female with May-Thurner Syndrome presents with left leg swelling, pain and + DVT A) Extensive DVT left leg B) Pure thrombolytic therapy performed with Unifuse catheter system and TNK for overnight infusion C) Uncovered irregular stenosis Left iliac vein D) Balloon venoplasty performed with improved appearance but residual stenosis remains E) Iliac venous stent placed now with widely patent venous flow through iliac veins

E)

A)

C)

Fig. 3. 54 y/o male with bilateral leg DVT and ilio-caval DVT A) Extensive ilio-caval thrombus B) and C) Kissing EKOS catheters placed simultaneously with TNK initiated for overnight infusion now with widely patent iliac veins and venacava on final images

Current Endovascular Treatments for Venous Thrombosis 85

A)

B)

C)

A) Extensive DVT identified B) Trellis thrombectomy device in SFV with balloon occlusion and mixed mechanical and pharmacological thrombolysis C) Marked improvement

Fig. 5. 59 y/o male with extensive DVT left leg swelling and pain

following Trellis device

Fig. 4. 71 y/o male with cardiopulmonary collapse/shock with bilateral pulmonary embolism A) and B) Bilateral extensive pulmonary embolism C) Bilateral simultaneous EKOS/TNK combination thrombolysis catheters in place D) Widely patent pulmonary arteries following 12 hour infusion

The Trellis device also combines mechanical and pharmacological thrombolysis. This device comes in various lengths and uses balloon occlusion technique to focus on the segmental clot burden. The "whip like" mechanical disruption breaks up the clot allowing the drug to act more effectively. (Fig 5) This is a useful device for isolated clot and can be performed as an outpatient with need for hospital admission.

The Possis AngioJet system can be both a pure mechanical and combination mechanical and pharmacological thrombolytic system. For combined systems, the Possis catheter is used in a "power pulse spray mode" where the thrombolytic drug is pulse sprayed directly into the clot. It is then allowed to sit in the vessel and dissolve the clot and then is removed by the standard angiojet thrombectomy fashion. This device can be used in many venous distributions with its various lengths and catheter treatment diameters. (Fig 6)

A) B)

C) D)

The Trellis device also combines mechanical and pharmacological thrombolysis. This device comes in various lengths and uses balloon occlusion technique to focus on the segmental clot burden. The "whip like" mechanical disruption breaks up the clot allowing the drug to act more effectively. (Fig 5) This is a useful device for isolated clot and can be performed as

The Possis AngioJet system can be both a pure mechanical and combination mechanical and pharmacological thrombolytic system. For combined systems, the Possis catheter is used in a "power pulse spray mode" where the thrombolytic drug is pulse sprayed directly into the clot. It is then allowed to sit in the vessel and dissolve the clot and then is removed by the standard angiojet thrombectomy fashion. This device can be used in many venous

distributions with its various lengths and catheter treatment diameters. (Fig 6)

Fig. 4. 71 y/o male with cardiopulmonary collapse/shock with bilateral pulmonary embolism A) and B) Bilateral extensive pulmonary embolism C) Bilateral simultaneous EKOS/TNK combination thrombolysis catheters in place D) Widely patent pulmonary

arteries following 12 hour infusion

an outpatient with need for hospital admission.

Fig. 5. 59 y/o male with extensive DVT left leg swelling and pain A) Extensive DVT identified B) Trellis thrombectomy device in SFV with balloon occlusion and mixed mechanical and pharmacological thrombolysis C) Marked improvement following Trellis device

Current Endovascular Treatments for Venous Thrombosis 87

The Pronto catheter (Pronto .035 extraction catheter, Vascular Solutions, Inc., Minneapolis, MN) is the newest pure mechanical device. Previously, developed from coronary interventions, it is now made for venous interventions. Pure aspiration catheters with large 8 French end hole-guiding catheters are used for cases with large clot burden such as

A B

C) D) Fig. 7. 31 y/o body building male with dominant right arm swelling and pain c/w Paget Schroetter syndrome A) Possis angiojet pure thrombectomy device cleared clot from subclavian vein B) Uncovered focal irregular stenosis in subclavian vein which is worse with adduction arm motion C) Balloon Venoplasty of right subclavian vein D) Patent right

Following mechanical or pharmacological thrombolysis for acute venous thrombolysis, additional endovascular interventions are usually necessary. Whether, there are focal stenoses uncovered following intervention as in Paget Schroetter syndrome, May -Thurner syndrome or fistula anastomoses in dialysis graft, there is typically some element of recoil in the vein, fixed stenosis or some chronic residual thrombus. Further interventions are

subclavian vein with all degrees of motion the right arm on final images

required involving balloon venoplasty, stent placement or filter placement.

**7. Additional venous interventions** 

massive pulmonary embolism and extensive deep venous thrombosis.

C)

Fig. 6. 61 y/o male with chronic pancreatitis with portal vein thrombosis A) Extensive portal vein thrombosis as seen on this transhepatic portogram B) Power pulse spray possis angiojet and TPA thrombolysis of the portal vein C) Improved patency of portal vein
