Stent Compression in Iliac Vein Compression Syndrome Associated with Acute Ilio-Femoral Deep Vein Thrombosis

Abstract

ObjectiveThis study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency.Materials and MethodsBetween May 2005 and June 2014, after stent placement for the treatment of IVCS with acute ilio-femoral deep vein thrombosis, follow-up CT venography was performed in 48 patients (35 women, 13 men; age range 23-87 years; median age 56 years). Using follow-up CT venography, the degree of the stent compression was calculated and used to divide patients into two groups. Possible factors associated with stent compression and patency were evaluated. The cumulative degree of stent compression and patency rate were analyzed.ResultsAll of the stents used were laser-cut nitinol stents. The proportion of limbs showing significant stent compression was 33%. Fifty-six percent of limbs in the significant stent compression group developed stent occlusion. On the other hand, only 9% of limbs in the insignificant stent compression group developed stent occlusion. Significant stent compression was inversely correlated with stent patency (p < 0.001). The median patency period evaluated with Kaplan-Meier analysis was 20.0 months for patients with significant stent compression. Other factors including gender, age, and type of stent were not correlated with stent patency. Significant stent compression occurred most frequently (87.5%) at the upper end of the stent (ilio-caval junction).ConclusionSignificant compression of nitinol stents placed in IVCS highly affects stent patency. Therefore, in order to prevent stent compression in IVCS, nitinol stents with higher radial resistive force may be required.

Doppler ultrasound and contrast-enhanced ultrasound in detection of stent stenosis after iliac vein stenting

“…An approximately oval shape can be seen at these levels of high compression, but a residual stenosis of more than 50% would be unacceptable [25]. A study [18] found that the proportion of signi cant stent compression was 33%; 56% of patients in the signi cant stent compression group developed stent occlusion, while only 9% developed stent occlusion in the insigni cant group, indicating that signi cant compression of the nitinol stents obviously affects stent patency. Additionally, the diameter reduction caused by stent compression may result in venous hypertension and residual symptoms of lower extremity, although patency may be retained [19].…”

“…All the ultrasound images were reviewed by two different ultrasonologists, and two different radiologists reviewed the MDCTV examinations, all reviewers were blinded to the history of patients and other imaging results. The degree of stent compression was evaluated by calculating the percentage of diameter reduction of the patent lumen of the stent (diameter of the stent at the narrowest segment/diameter of the stent at the normal segment × 100%) [18]. The degree of stent compression was de ned as "signi cant" if the luminal collapse was 50% or more and as "insigni cant" if the luminal collapse was below 50%.…”

“…Despite these therapeutic bene ts, stent dysfunctions such as stent compression and in-stent stenosis (ISR) are common complications [5,14,17]. Signi cant compression of nitinol stents highly affects stent patency [18], and it has been reported that approximately 20 percent of stents will require reintervention for ISR [19].…”

Doppler ultrasound and contrast-enhanced ultrasound in detection of stent stenosis after iliac vein stenting

“…All the ultrasound images were reviewed by two different ultrasonologists, and two different radiologists reviewed the MDCTV examinations, all reviewers were blinded to the history of patients and other imaging results. The degree of stent compression was evaluated by calculating the percentage of diameter reduction of the patent lumen of the stent (diameter of the stent at the narrowest segment/diameter of the stent at the normal segment × 100%) [ 17 ]. The degree of stent compression was defined as “significant” if the luminal collapse was 50% or more and as “insignificant” if the luminal collapse was below 50%.…”

“…Despite these therapeutic benefits, stent dysfunctions such as stent compression and in-stent restenosis (ISR) are common complications [ 5 , 14 , 16 ]. Significant compression of nitinol stents highly affects stent patency [ 17 ], and it has been reported that approximately 20 percent of stents will require reintervention for ISR [ 18 ].…”