Management of inferior vena cava thrombosis with the FlowTriever and ClotTriever systems.

Objective: Although inferior vena cava (IVC) thrombosis is infrequently encountered, it carries a significant risk of post-thrombotic syndrome and pulmonary embolus. Recent studies show no difference in the incidence of post-thrombotic syndrome in patients with iliofemoral deep venous thrombosis (DVT) treated with pharmacothrombolysis vs anticoagulation alone; however, there is an associated increased risk of bleeding. The treatment of IVC thrombosis is less well-studied and the hemodynamic changes may be more significant with pharmacothrombolysis, although the bleeding risk remains. The ClotTriever and FlowTriever systems remove thrombus from veins without the use of thrombolytics. Our study evaluates outcomes of patients undergoing mechanical thrombectomy for the treatment of IVC thrombosis using the ClotTriever and FlowTriever devices.

Methods: A retrospective chart review was performed to identify consecutive patients who underwent mechanical thrombectomy for the treatment of IVC thrombosis using the ClotTriever and/or FlowTriever systems from November 2018 to January 2020 at four data-sharing institutions. The decision of which device(s) to use was at the discretion of the surgeon. Patient demographics, symptomatology, and imaging characteristics were captured at presentation and follow-up.

Results: A total of 15 patients met the inclusion criteria; 10 were male, and the average age was 59 years. The majority of patients were symptomatic at presentation (n = 14), had a prior history of DVT (n = 13), and had a preexisting IVC filter (n = 8). Eleven patients presented with acute onset (<1 week) of symptoms, whereas three patients had subacute (1-4 weeks) symptoms. Most patients had an associated iliofemoral DVT (n = 13) and were treated with both ClotTriever and FlowTriever (n = 8); others were treated with either ClotTriever or FlowTriever alone (n = 5 and n = 2, respectively). Technical success was achieved in all but two patients, one who had a nonocclusive thrombus densely adherent to a preexisting IVC filter and another who had a chronic rubbery clot in the IVC that could not be cleared. No patient required concomitant lytic therapy or a postoperative stay in the intensive care unit. Furthermore, there were no postoperative bleeding events, myocardial infarctions, pulmonary emboli, renal impairments, or deaths. The median length of stay was 3 days (range, 1-37 days). Patients underwent postoperative follow-up (n = 7) as well as extended follow-up (>6 months; n = 8). All patients who achieved technical success were asymptomatic without evidence of reocclusion of the IVC on follow-up imaging.

Conclusions: In our multicenter series of 15 patients, The ClotTriever and FlowTriever showed promise in the treatment of IVC thrombosis without the use of fibrinolytic drugs, with no bleeding events and no requirement for intensive care unit stay.