69 Apollo Medicine, Vol.1 September 2004

Patient 2

A 47-year male patient presented with right painfulswelling of the lower limb for the last 3 days. He is a smoker,diabetic and hypertensive. Except for smoking, no major riskfactors for DVT were identified. Venous Doppler revealedDVT of the right ileo-femoral vein with extension into theIVC. He was immediately given a bolus of 8000 units ofheparin I/V (100 units/Kg) and an infusion of 1400 units/hr(18 units/Kg/hr). The heparin infusion was titrated to keep thePTT at 2.5-3 times the control. On third day of admission, hedeveloped mild pain on the right side of the chest. Lungexamination and a chest X-ray were clear. ABG wasunremarkable and ventilation-perfusion lungs scan showedhigh probability of PE in the right upper lung field. Atemporary IVC filter (Tempo Filter II, B Braun) was insertedvia the right internal jugular vein till just below the renal veins.The filter was explanted after six weeks without furtherepisodes of PE or any other complications. A repeatventilation-perfusion lungs scan before discharge did notreveal any new areas of mismatch. He continues to do well 4months after the episode.

DISCUSSION

The concept of interrupting the flow in the inferior venacava (IVC) to prevent PE originated in the 1930s and 1940swith the performance of common femoral vein and superficialfemoral vein ligation. These methods were used in parallelwith anticoagulation methods when heparin and warfarinbecame available in 1935 and 1948 respectively. Later,ligation of the IVC was performed, initially in patientsharboring thrombi above the superficial femoral veins.Eventually, it replaced lower-level venous ligation. Theoperative mortality rate of 2-15% was not significantlydifferent from that of femoral vein ligation, but a lower rate forrecurrent PE was reported. The optimal level of ligation waslocated immediately below the renal veins to prevent

INFERIOR Vena Caval Filters (IVC) have been used since1967 for the prevention of life threatening pulmonaryembolism in deep vein thrombosis (DVT). As all filters havethe potential to lead to caval thrombosis, all patients withIVC filters require lifelong anticoagulant therapy. Filtershave now been developed that can be removed after varyingperiods of time. These fourth generation filters have theadvantage of providing protection against PE and then canbe removed. Thus, patients can discontinue anticoagulantsafter 6-12 months. My initial experience with two suchpatients is described.

CASE REPORTS

Patient 1

A 36-year male patient presented to the emergency roomwith two-week-old head injury and consequent intra-cranialhematoma. The intra-cranial hematoma did not require anysurgical intervention and had been managed conservativelyby the neurosurgeon. The patient had developed swelling ofthe whole of the right lower limb 2 days before presentation.On examination, he was conscious, alert and oriented withno neurological deficit. Vital signs were stable and systemicexamination was unremarkable. The whole of the right lowerlimb was swollen till the groin. Venous Dopplerinterrogation revealed DVT of the right ileo-femoral veinand the thrombus extending into the IVC. Due to the recenthead injury with an intracranial hematoma, anti-coagulationwas contra-indicated. On the other hand, the thrombusextending into the IVC placed the patient at high risk for alife threatening thrombus. After discussing all options withthe patient and family, a temporary IVC filter (TempoFilter II, BBraun) was inserted via the right internal jugularvein till just below the renal veins. The filter was removedafter six weeks. He continues to do well without furthercomplications.

INITIAL EXPERIENCE WITH FOURTH GENERATION INFERIOR VENA CAVAL FILTERS

Umesh GuptaFrom the Department of Vascular Surgery, Apollo Surgical Sciences Centre, Indraprastha Apollo Hospitals, New Delhi 110 044, India.

Correspondence to: Dr. Umesh Gupta, Consultant Vascular Surgeon, Team leader-JCI DICE,Indraprastha Apollo Hospitals, New Delhi 110 044, India.

E-mail: uhgupta@hotmail.com

The fourth generation temporary inferior vena cava (IVC) filter was used with good outcomes in two patients of deepvein thrombosis (DVT) with high likelihood of life threatening pulmonary embolism (PE).

Key words: Deep vein thrombosis, Pulmonary embolism, Inferior vena caval filter

Case Reports

Apollo Medicine, Vol.1 September 2004 70

Case Reports

thrombosis due to venous stasis between the interrupted IVCand the renal veins. However, 10-16% of these patients hadimmediate lower-extremity swelling.

In the 1960s, various methods of partially interrupting theflow in the IVC were developed to lessen the effect of venousstasis. The procedures provided emboli trapping withpreservation of blood flow through the lumen. The proceduresinclude suture plication and caval clips (Moretz clip, Milesclip, Adams-DeWeese clip). The rates for operative mortalityand recurrent PE were similar to those of caval ligation, yet therate for limb edema was reduced. Despite the fact that theseprocedures partially interrupted flow in the IVC, cavalocclusion rates of 30-40% were reported.

In 1967, the Mobin-Uddin umbrella filter was developedas a replacement for surgical ligation, caval plication, andcaval clips and partially to interrupt the flow in the IVC and toprevent PE. Since then, several filters have been introduced.Currently, filters represent the standard of care when partialinterruption of IVC flow is indicated to prevent the occurrenceof PE. The classical indications for IVC filters arecontraindication to anticoagulation or recurrent PE despiteadequate anticoagulation [1,2]. Less frequent indicationsinclude prophylaxis and perioperative coverage.

All IVC Filters have the potential to cause IVCthrombosis [3,4]. Further, patients with IVC filters requirelifelong anticoagulation. Other uncommon complications ofpermanent filters include IVC perforation, filter migrationetc. [5-8].

Fourth generation IVC filters were developed to overcomethe complication of IVC thrombosis as these filters can beremoved after the period of greatest chances of occurrence ofPE is over, usually six weeks. Further, as the filter isremovable, patients do not require lifelong anticoagulationwith its attendant expenses and complications. These filtersare further classified as removable or retrievable. Difference isthat the retrievable filters can be either left inside or removeddepending on the continued indication for the filter.Removable filters have a tethering catheter and the filter mustbe removed within six weeks of insertion.

Patients of polytrauma or those requiring urgent surgeryand also have DVT, require prophylactic coverage forprevention of PE as anticoagulation is contraindicated [9-12].Such patients are ideally suited for the fourth generation IVCfilters.

Anticoagulation was contraindicated in the first patientdue to recent head injury with concomitant intracranialhemorrhage. The DVT was extending to his IVC and hence, hehad a real threat of developing life threatening PE. As thepatient is a young man with a long life ahead of him, aconventional IVC filter would have meant possible IVCthrombosis with subsequent bilateral chronic venous

insufficiency. Implanting and then explanting the temporaryfilter after 6 weeks has resulted in prevention of mortality aswell as an anticoagulation free life.

The second patient with documented PE despite adequateanticoagulation was a classical indication for IVC filterplacement. Again, a temporary filter has resulted in preventionof further PE and an anticoagulation free life after 4 months oftherapy.

Both the cases demonstrate the effectiveness of thetemporary filters and a good quality of life afterwards.

The main drawback of the temporary filters is the lack oflong-term results and complication data of these filters. Tillsuch data is available, the fourth generation IVC filters shouldbe used very selectively and under close monitoring.REFERENCES1. Vaughn BK, Knezevich S, Lombardi AV Jr, Mallory TH. Use of

the Greenfield filter to prevent fatal pulmonary embolismassociated with total hip and knee arthroplasty. J Bone JointSurg Am 1989 Dec; 71(10): 1542-1548.

2. Wittenberg G, Kueppers V, Tschammler A, et al. Long-termresults of vena cava filters: experiences with the LGM and theTitanium Greenfield devices. Cardiovasc Intervent Radiol1998 May-Jun; 21(3): 225-229.

3. Thomas JH, Cornell KM, Siegel EL, et al. Vena cavalocclusion after bird’s nest filter placement. Am J Surg 1998Dec; 176(6): 598-600.

4. Starok MS, Common AA. Follow-up after insertion of Bird’sNest inferior vena caval filters. Can Assoc Radiol J 1996 Jun;47(3): 189-194.

5. Athanasoulis CA, Kaufman JA, Halpern EF, et al: Inferior venacaval filters: review of a 26-year single-center clinicalexperience. Radiology 2000 Jul; 216(1): 54-66.

6. Awh MH, Taylor FC, Lu CT. Spontaneous fracture of a Vena-Tech inferior vena caval filter. AJR Am J Roentgenol 1991 Jul;157(1): 177-178.

7. LaPlante JS, Contractor FM, Kiproff PM, Khoury MB.Migration of the Simon nitinol vena cava filter to the chest. AJRAm J Roentgenol 1993 Feb; 160(2): 385-386.

8. Teitelbaum GP, Jones DL, van Breda A, et al. Vena caval filtersplaying: potential complication of use of the titaniumGreenfield filter. Radiology 1989 Dec; 173(3): 809-814.

9. Gosin JS, Graham AM, Ciocca RG, Hammond JS. Efficacy ofprophylactic vena cava filters in high-risk trauma patients. AnnVasc Surg 1997 Jan; 11(1): 100-105.

10. Greenfield LJ, Proctor MC, Michaels AJ, Taheri PA.Prophylactic vena caval filters in trauma: the rest of the story.J Vasc Surg 2000 Sep; 32(3): 490-5; discussion 496-497.

11. Langan EM 3rd, Miller RS, Casey WJ 3rd, et al. Prophylacticinferior vena cava filters in trauma patients at high risk: follow-up examination and risk/benefit assessment. J Vasc Surg1999 Sep; 30(3): 484-488.

12. Rogers FB, Shackford SR, Ricci MA, et al. Prophylactic venacava filter insertion in selected high-risk orthopaedic traumapatients. J Orthop Trauma 1997 May; 11(4): 267-272.