Approach Considerations
Once the diagnosis has been confirmed, the clinician must choose an appropriate treatment regimen for inferior vena cava (IVC) thrombosis (IVCT) on the basis of the underlying pathophysiology. Both surgical and medical options are available. Medical professionals are encouraged to investigate the most recent research to keep apprised of the latest information relating to the various risks and benefits of treatment modalities.
In the broadest sense, surgical therapy of IVCT encompasses caval interruption and thrombectomy. Currently, both of these modalities are being used less frequently.
There is very little evidence available on the surgical correction or the treatment of a complete absence of the IVC. A case report, in which there was a complete absence of the IVC but patent iliac veins and nonhealing pretibial ulceration, described successful treatment with a prosthetic graft from the iliac vein to the intrathoracic azygos vein. [40] Authors of another case report concluded, on the basis of their review of the available literature, that surgical options in this patient population are limited. [51]
Go to Deep Venous Thrombosis for more complete information on this topic.
The goals of therapy center on managing the primary impact of deep vein thrombosis (DVT) and the impact of embolization. Medical management can include anticoagulation therapy and thrombolytic agents (see Medication).
Anticoagulants and Thrombolytic Agents
Heparin or warfarin may be used to prevent the propagation of thrombi. One group reported no embolic events with this therapy, even with so-called free-floating IVCT. However, propagation may still occur. Therapy is usually converted to oral anticoagulation with warfarin, but the time course of warfarin therapy is somewhat empiric.
Most thrombolytic agents have been reported in the treatment of IVCT. The relative merits of thrombolytic therapy must be weighed against the risks of hemorrhagic complications.
Urokinase, tissue-type plasminogen activator (tPA), and streptokinase have all been used. Typically, delivery is catheter-directed, with or without a pulse spray. Patients require concurrent heparin therapy; however, tPA protocols do not use concurrent heparin because of the risk of bleeding complications.
Up to a 25% risk of pulmonary embolism (PE) during therapy has been reported. Some reports advocate using filters above the thrombolysis site [52] ; some do not. This therapy may play the greatest role as part of combination therapy with endovascular interventions.
Caval Interruption
When using ligation for caval interruption, the proper level must be chosen. Ligation effects a permanent, complete occlusion of the IVC, but the risk of recurrent PE is not zero.
Filters are relatively noninvasive, allow central flow, and may be placed at several different anatomic levels as indicated by the clinical situation. However, thrombosis may occur at the insertion site or at the site of the filter itself. There are numerous proprietary configurations of filters available, and the technology is constantly changing; therefore, data from older studies may not extrapolate to current devices.
Go to Inferior Vena Cava Filters for more complete information on this topic.
Thrombectomy and Endovascular Intervention
Thrombectomy is often carried out for therapy of phlegmasia, but rethrombosis rates are significant and thrombectomy often does not completely remove the thrombus. The procedure is typically performed in conjunction with a distal arteriovenous fistula to maintain high flow, and it may be required for cases of septic thrombus. The operative mortality is reportedly 2%; the morbidity is 30%.
Endovascular interventions
Endovascular techniques are particularly helpful to treat patients with IVCT that has arisen from iatrogenic causes (see Etiology). The numerous clinical scenarios that lend themselves to this approach can include (1) long-term venous access, (2) hemodialysis access, and (3) surgery on the IVC, including hepatic transplantation.
Several interventional modalities are available to treat IVCT. The optimal result can often be obtained by using a combination of the following options:
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Percutaneous balloon angioplasty
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Wallstents
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Z stents
The number and type of expandable stents are changing as product development continues. The various stents have limitations both in vessel diameter and length of available stent. Consulting with vascular surgeons, radiologists, and available literature to identify the locally available devices is encouraged and recommended.
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Virchow triad/venous thromboembolism (VTE) risk factors.
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Photo showing dilated superficial abdominal veins (upper quadrant), with bruising and thrombosed large abdominal veins (lower quadrant).
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Abdominal CT scan shows absent inferior vena cava with thrombosis of very prominent collateral veins in the abdominal wall, corresponding to right side of abdomen as seen in earlier photo.
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Veins of abdomen and thorax. Unless stated otherwise, lithograph plate is from Gray's Anatomy (online edition of the 20th US edition of Gray's Anatomy of the Human Body, originally published in 1918).
