1. Clinical case Case Presentation: IVC Retrievable and Permanent Filters
Antonios P Gasparis, MD
Professor of Surgery
Director, Center for Vein Care
Stony Brook Medicine

2. 72 year-old male with chronic atrial fibrillation not on anticoagulation presented with aphasia and right-sided hemiplegia.
CT (computed tomography) head showed left medial cerebral artery (MCA) infarct.
Patient underwent t-PA and mechanical thrombectomy.

3. Which of the following options would be the most appropriate for post-procedure Deep Vein Thrombosis (DVT) prophylaxis?
Intermittent pneumatic compression
Elastic compression stockings
Chemical prophylaxis
Surveillance ultrasounds
Inferior vena cava (IVC) filter

4. Which of the following options would be the most appropriate for post-procedure Deep Vein Thrombosis (DVT) prophylaxis?
Intermittent pneumatic compression
Elastic compression stockings
Chemical prophylaxis
Surveillance ultrasounds
Inferior vena cava (IVC) filter

5. On day #4 of admission, a CT pulmonary angiogram (CTPA) was ordered to evaluate a lesion in the right upper lobe that was seen in a previous chest x ray (CXR).

6. Polo mint sign
CTPA shows multiple filling defects within the pulmonary vasculature consistent with acute pulmonary embolism (PE)

7. What is the next step?

8. Bilateral lower extremity duplex ultrasound (DUS) to rule out DVT was ordered.

9. DUS shows lack of compressibility, filling defects and minimum flow in the right popliteal vein (POP V).

10. DUS shows lack of compressibility, filling defects and minimum flow in the left POP V.

11. A follow-up CT head showed evolving left basal ganglia and corona radiata MCA territory infarct with interval development of petechial hemorrhage along the periventricular white matter.

12. How would you manage this patient’s DVT/PE?
Systemic anticoagulation
IVC filter insertion
Catheter-directed thrombolysis (CDT)
Mechanical thrombectomy
Follow-up ultrasound

13. How would you manage this patient’s DVT/PE?
Systemic anticoagulation
IVC filter insertion
Catheter-directed thrombolysis (CDT)
Mechanical thrombectomy
Follow-up ultrasound

14. What type of filter and access site?

15. A Cook Tulip IVC filter was inserted via right femoral approach.

16. 4 - week follow-up
CT head reported “evolving late subacute to chronic left basal ganglia infarction with no evidence of intracranial hemorrhage”.
Warfarin (VKA) was started.

17. Any imaging prior to retrieval?
8 - week follow-up
Referred to vascular surgery for IVC filter retrieval
Any imaging prior to retrieval?

18. 8 - week follow-up
DUS shows lack of compressibility, filling defects and absence of flow in the right POP V (no change from initial DUS).

19. DUS shows new filling defect in the left external iliac vein (EIV).

20. DUS shows lack of compressibility, filling defects and absence of flow in the left common femoral vein (new).

21. DUS shows lack of compressibility, filling defects and absence of flow in the left femoral vein (new).

22. Now what?

23. Cavogram for IVC filter retrieval at 8 weeks after VKA being started shows IVC filter thrombosis.

24. What would be the most appropriate next step?
Thrombolysis for IVC thrombus
Angiovac
Continue anticoagulation
Supra-renal IVC filter
Retrieve the IVC filter

25. What would be the most appropriate next step?
Thrombolysis for IVC thrombus
Angiovac
Continue anticoagulation
Supra-renal IVC filter
Retrieve the filter

26. Discussion
Although IVC filters reduce the risk of PE, they can increase the risk of other complications such as IVC thrombosis.
Decousus H., Leizorovicz A., Parent F., Page Y., Tardy B.,Girard P., et al  A clinical trial of vena caval filters in the prevention of pulmonary embolism in patients with proximal deep‐vein thrombosis. Prévention du Risque d'Embolie Pulmonaire par Interruption Cave Study Group. N. Engl. J. Med. 338:409–415. 
The incidence of IVC filter thrombosis ranges from 13-30%.
Group PS  Eight‐year follow‐up of patients with permanent vena cava filters in the prevention of pulmonary embolism: the PREPIC (Prevention du Risque d'Embolie Pulmonaire par Interruption Cave) randomized study. Circulation 112:416–422
Pan Y, Zhao J, Mei J, et al. Retrievable Inferior Vena Cava Filters in Trauma Patients: Prevalence and Management of Thrombus Within the Filter. Eur J Vasc Endovasc Surg. 2016 Sep 27

27. Discussion
Highest risk factors for IVC filter thrombosis include age, type of filter and lack of anticoagulation therapy
Tardy B., Mismetti P., Page Y., Décousus H. Da Costa A., Zeni F., et al  Symptomatic inferior vena cava filter thrombosis: clinical study of 30 consecutive cases. Eur. Respir. J. 9:2012–2016.
Retrieval rates of inferior vena cava (IVC) filters in US hospitals range from %. The most common reason for failure in retrieval was filter thrombus.
Peterson EA, Yenson PR, Liu D, at al. Predictors of attempted inferior vena cava filters retrieval in a tertiary care centre. Thromb Res. 2014 Aug;134(2):300-4.

28. Discussion
Various techniques for retrieval of a thrombosed IVC filter has not been reported including: CDT, mechanical thrombectomy, laser-assisted removal, or combination of different modalities.
The retrieval rate for IVC filter thrombosis ranges from 75 – 100% in different series.
Jiang J, Tu J, Jia Z, at al. Incidence and Outcomes of Inferior Vena Cava Filter Thrombus during Catheter-directed Thrombolysis for Proximal Deep Venous Thrombosis. Ann Vasc Surg. 2016 Aug 12.
Branco BC, Montero-Baker MF, Espinoza E, et al. Pharmacomechanical thrombolysis in the management of acute inferior vena cava filter occlusion using the Trellis-8 device.J Endovasc Ther Feb;22(1):

29. 764 patients having filters implanted were referred for filter removal
Discussion
764 patients having filters implanted were referred for filter removal
The incidence of infra-filter thrombus was 30.9% (236 cases), and occlusion of the filter bearing IVC was seen in 2.4% (18) of cases
121 cases with small clots – retrieval with snare and sheath technique
116 cases with massive thrombus – CDT and/or negative pressure aspiration
213 cases (90.3%) of thrombus in the filter were removed successfully without PE
Pan Y, Zhao J, Mei J, et al. Retrievable Inferior Vena Cava Filters in Trauma Patients: Prevalence and Management of Thrombus Within the Filter. Eur J Vasc Endovasc Surg. 2016 (In Press)