Placement of closed-cell designed venous stents in a mixed cohort of patients with chronic venous outflow obstructions - short-term safety, patency, and clinical outcomes.

BACKGROUND: To evaluate the performance of a closed-cell designed venous stent for the treatment of chronic ilio-femoral venous outflow obstruction (VOO) in the shortterm. PATIENTS AND METHODS: Safety, stent patency and clinical outcome after placement of the Vici Venous Stent® in patients with chronic ilio-femoral venous obstruction were assessed retrospectively. Stent patency was evaluated by duplex ultrasound scanning, and clinical outcome was determined using the revised Venous Clinical Severity score (rVCSS). RESULTS: 75 patients (49 % female; median age 57 years; 82 limbs) with symptomatic significant VOO had stents placed in the ilio-femoral veins. Lower limb venous skin changes including ulcers (C-class in CEAP 4-6) were found in 31 patients (41 %). Nonthrombotic iliac vein lesions (NIVLs) and post-thrombotic obstruction (PTO) were found in 40 and 42 limbs, respectively. There were no safety issues. Cumulative primary, assisted-primary, and secondary stent patency in the entire cohort at 12 months were 94 %, 94 % and 96 %, respectively. Five limbs presented with stent occlusion. Two limbs had no intervention, 2/3 remained patent after reintervention. Clinical improvement (a decrease ≥ 2 rVCSS points) was observed in 81 %, 81 %, and 77 % of patients at 1 month, 6 months, and 12 months, respectively. There was a marked drop in the frequency of more marked pain and swelling (VCSS ≥ 2) from 62 % to 5 % and 93 % to 19 %, respectively. Four limbs had venous ulcers, three healed during the follow-up. Cumulative pri- mary stent patency at 12 months was 100 % and 87 % in patients with NIVL and PTO, respectively (p= 0.032). There was no statistical difference in clinical outcome between these subgroups. CONCLUSIONS: The Vici Venous Stent® placed in the ilio-femoral vein segment in patients with symptomatic VOO revealed no safety issues, had excellent primary patency and substantial symptom improvement. Long-term studies are needed to evaluate the durability of this stenting procedure.

The initial report on 1-year outcomes of the feasibility study of the VENITI VICI VENOUS STENT in symptomatic iliofemoral venous obstruction.

OBJECTIVE: The objective of this study was to assess the safety and efficacy of a dedicated venous stent (the VICI VENOUS STENT; VENITI, Fremont, Calif) for treatment of symptomatic iliofemoral venous outflow obstruction. METHODS: Thirty patients (24 female; median age, 43 years) were enrolled in the feasibility phase of an international, multicenter investigational device exemption trial from June 2014 to February 2015. All patients exhibited unilateral venous disease with ≥50% stenosis in the iliofemoral veins. Patients within 3 months of acute deep venous thrombosis or with prior surgical or endovascular intervention of the target vessel were excluded. Lesions were primarily of post-thrombotic causes (63%), with a left limb-right limb ratio of 5:1. Nine patients (30%) had lesions extending beneath the inguinal ligament. Median baseline stenosis was 91%; 11 patients (37%) had occlusions. RESULTS: Fifty-one stents were implanted successfully in 30 patients. Median residual stenosis was 0%, as estimated by venography and intravascular ultrasound. Median follow-up was 701 days. At 12 months, primary, assisted-primary, and secondary patency was 93%, 96%, and 100%, respectively. The stent occluded in two patients through the 12-month window (occurring at 19 and 385 days). Both occlusions occurred in patients presenting with post-thrombotic obstruction. No patients in this cohort exhibited stent fracture at 12 months. Symptomatic improvement of ≥2 points on the Venous Clinical Severity Score was observed in 23 patients (85%) at 12 months (median score improvement, 5 points). There was a median 12-month pain reduction of 20 mm on the visual analog scale score and 15-point improvement on the Chronic Venous Insufficiency Questionnaire score. Scores improved significantly on all three clinical and quality of life scales at 6 and 12 months. CONCLUSIONS: The VICI VENOUS STENT is safe and feasible for treatment of symptomatic iliofemoral venous obstruction, with excellent 12-month patency rates and significant improvement seen in clinical symptoms and quality of life indices. The pivotal phase (170 patients, 22 centers) of this investigational device exemption trial is currently ongoing.

Diagnosis and treatment of venous lymphedema.

BACKGROUND: Chronic venous disease (CVD) is a common cause of secondary lymphedema. Venous lymphedema is sometimes misdiagnosed as primary lymphedema and does not receive optimal treatment. We have routinely used intravascular ultrasound (IVUS) imaging in all cases of limb swelling. The aim of this study is to show that (1) routine use of IVUS can detect venous obstruction missed by traditional venous testing, and (2) iliac-caval venous stenting can yield satisfactory clinical relief and can sometimes reverse abnormal lymphangiographic findings. METHODS: The study comprised CVD patients who underwent iliac vein stenting. Lymphangiography was abnormal in 72 of 443 CEAP C(3) limbs, with leg swelling as the primary complaint (abnormal lymphangiography group). Clinical features and stent outcome were compared with a control group of 205 of 443 with normal lymphangiography (normal lymphangiographic group). RESULTS: Clinical features were a poor guide to the diagnosis of lymphedema. Isotope lymphangiography was not helpful in differentiating primary from secondary lymphedema. Venography had 61% sensitivity to the diagnosis of venous obstruction. IVUS had a sensitivity of 88% for significant (≥50% area stenosis) venous obstruction. At 40 months, cumulative secondary stent patency was similar for the abnormal (100%) and normal lymphangiographic (95%) groups. Swelling improved significantly after stent placement in the abnormal lymphangiographic group (mean [standard deviation] swelling grade improvement 0.8 ± 1.1) but was less (P < .004) than in the control group (1.4 ± 1.3). Complete swelling relief was 16% and 44% (P < .001) and partial improvement (≥1 grade of swelling) was 45% and 66% (P < .01) in the abnormal and normal lymphangiographic groups, respectively. Associated pain was present in 50% and 36% of the swollen limbs in the abnormal and normal lymphangiographic groups. Pain relief (≥3 visual analog scale) at 40 months was 87% and 83%, respectively (P = .3), with 65% and 71%, experiencing complete pain relief. Quality of life criteria improved after stent placement in both groups but to a better extent in the normal lymphangiographic group. Abnormal lymphangiography improved or normalized in 9 of 36 (25%) of those tested after stent correction. CONCLUSIONS: Prevailing practice patterns and diagnostic deficiencies probably result in the misdiagnosis of many cases of venous lymphedema as "primary" lymphedema. IVUS is recommended to rule out venous obstruction as the associated or initiating cause of lymphedema. Iliac venous stenting to correct the obstruction has excellent long-term patency and good clinical outcome, although results are not as good as in those with normal lymphatic function.

Multicenter assessment of venous reflux by duplex ultrasound.

OBJECTIVE: This prospective multicenter investigation was conducted to define the repeatability of duplex-based identification of venous reflux and the relative effect of key parameters on the reproducibility of the test. METHODS: Repeatability was studied by having the same technologist perform duplicate tests, at the same time of the day, using the same reflux-provoking maneuver and with the patient in the same position. Reproducibility was examined by having two different technologists perform the test at the same time of the day, using the same reflux-provoking maneuver and with the patient in the same position. Facilitated reproducibility was studied by having two different technologists examine the same patients immediately after an educational intervention. Limits of agreement between two duplex scans were studied by changing three elements of the test: time of the day (morning vs afternoon), patient's position (standing vs supine), and reflux initiation (manual vs automatic compression-decompression). RESULTS: The study enrolled 17 healthy volunteers and 57 patients with primary chronic venous disease. Repeatability of reflux time measurements in deep veins did not significantly differ with the time of day, the patient's position, or the reflux-provoking maneuver. Reflux measurements in the superficial veins were more repeatable (P < .05) when performed in the morning with the patient standing. The agreement between the clinical interpretations significantly depended on a selected cut point (Spearman's ρ, -0.4; P < .01). Interpretations agreed in 93.4% of the replicated measurements when a 0.5-second cut point was selected. The training intervention improved the frequency of agreement to 94.4% (κ = 0.9). Alternations of the time of the duplex scan, the patient's position, and the reflux-provoking maneuver significantly decreased reliability. CONCLUSIONS: This study provides evidence to develop a new standard for duplex ultrasound detection of venous reflux. Reports should include information on the time of the test, the patient's position, and the provoking maneuver used. Adopting a uniform cut point of 0.5 second for pathologic reflux can significantly improve the reliability of reflux detection. Implementation of a standard protocol should elevate the minimal standard for agreement between repeated tests from the current 70% to at least 80% and with more rigid standardization, to 90%.

Stenting of chronically obstructed inferior vena cava filters.

OBJECTIVES: A protective inferior vena cava (IVC) filter may later be incorporated into a chronic postthrombotic ilio-caval obstruction (occlusive, requiring recanalization, or nonocclusive). This study aims to assess the safety and stent-related outcome following stenting across an obstructed filter. METHODS: From 1997 to 2009, 708 limbs had stenting for postthrombotic ilio-caval outflow obstruction (occlusion in 121 limbs). In 25 patients, an IVC filter was obstructed (Group X). The site was crossed by a guidewire and balloon dilated. The filter was markedly displaced sidewise or remodeled. A stent was placed across the IVC filter and redilated. In 28 other patients, the cephalad stenting terminated below a patent IVC filter (Group B). The remaining 655 patients had no previous IVC filter placement (Group no IVC filter present [NF]). The patients were followed to assess patency. The types of reintervention were noted. RESULTS: The stenting maneuver through a variety of previously inserted IVC filters was safely performed without an apparent tear of the IVC, no clinical bleeding or abdominal symptoms, or pulmonary embolism. Mortality was nil; morbidity minimal. The primary and secondary cumulative patency rates at 54 months for limbs with postthrombotic obstruction were with and without IVC filter (38% and 40%; P = .1701 and 79% and 86%; P = .1947, respectively), and for limbs with stenting across the filter (Group X) and stent termination below the filter (Group B; 32% and 42%; P = .3064 and 75% and 84%; P = .2788, respectively), not statistically different. When Group X alone was compared with Group NF, the secondary patency rate was, however, significantly lower (75% vs 86%; P = .0453), suggesting that crossing of the stent was associated with reduced patency. Occlusive postthrombotic disease requiring recanalization was more frequent in Group X than in Group B and Group NF (68%, 25%, and 15%, respectively; P = .004). A comparison was therefore performed only between limbs stented for recanalized occlusions with (n = 23) and without IVC filters (n = 92) showing no difference (cumulative primary and secondary patency rates 30% and 35%; P = .9678 and 71% and 73%; P = .9319, respectively). Multiple logistic regression analysis also supported a significant association between patency rate and occlusive disease (odds ratio, 6.9; 95% confidence interval, 3.4-13.9; P < .0001), but not between patency rate and presence of an IVC filter (P = .5552). CONCLUSIONS: Stenting across an obstructed IVC filter is safe. It appears that patency is not influenced by the fact that an IVC filter is crossed by a stent, but is related to the severity of postthrombotic disease (occlusive or nonocclusive obstruction) and the associated recanalization procedure.

Iliac vein stenting in postmenopausal leg swelling.

BACKGROUND: Leg swelling in menopausal women is well known. Prevailing concept in primary care is that it is polycentric and a treatable cause may not be found. Patients are placed on empiric diuretics often without benefit. Our clinical experience indicates that iliac venous vein obstruction is the core cause; a variety of secondary factors common in postmenopausal women precipitate symptoms. PATIENTS AND METHODS: A total of 163 limbs in 150 postmenopausal women (≥ 55 years of age) with leg swelling unresponsive to conservative therapy underwent intravascular ultrasound-guided iliac vein stenting over an 11-year period. Preoperative investigations included duplex, airplethysmography, venous pressure tests, contrast studies, and lymphangiography. The postmenopausal group constituted 9% of all limbs (n = 1760) stented for chronic venous disease (CVD) during the same period and 18% of those stented for swelling (n = 922). Median age was 67 (range, 55-92) and left-to-right ratio 2:1. RESULTS: Iliac vein obstruction was "primary" (nonthrombotic) in 65% and postthrombotic in 35% of limbs; 35% of limbs had obstruction only and 65% combined obstruction/reflux. Lymphatic dysfunction was present in 21% of the limbs. Mean intravascular ultrasound area stenosis was 68% ± 22 SD. Mean follow-up was 22 months (± 26 SD) (range, 1-113 months). Secondary stent patency (6 years) was 100% in primary and 91% in postthrombotic limbs; overall 98%. Swelling improved significantly (P < .0001) from preoperative grade 2.5 (± 0.8 SD) to postoperative grade 1.2 (1.2 SD). Associated pain also improved significantly (P < .0001) from preoperative visual analog scale 3.5 (± 3 SD) to postoperative 0.9 (2.1 ± SD). Quality-of-life (CIVQ) scores improved significantly in every category and overall (P < .0001). CONCLUSIONS: Patients with postmenopausal leg swelling often have obstructive venous pathology even though suggestive venous history and other signs are often absent. Morbidity arises from painful swelling that affects mobility, quality of life, and ability of self-care at later stages of life. Outpatient percutaneous iliac vein stenting affords substantial symptom relief and improvement in quality-of-life measures. Recognition of the clinical complex as a distinct entity of venous origin may lead to greater awareness and effective treatment.

Bilateral stenting at the iliocaval confluence.

OBJECTIVE: This study describes three techniques of stent placement at the iliocaval confluence for chronic nonmalignant obstruction and its stent-related outcome. METHODS: From 1997 to 2008, 115 patients (230 limbs) underwent bilateral stenting for iliocaval obstruction. All limbs were CEAP classified using clinical examination and duplex ultrasound study. Three techniques were compared: placement of two stents side by side in a "double-barrel" (group DB, n = 39); inverted Y stenting through a fenestra (window) created through the side braiding of a stent placed previously across the iliocaval confluence (group iY, n = 38); apposition of a stent as close as possible to a stent previously placed across the iliocaval confluence, leaving a small area unsupported between the stents (group A, n = 38). Patency was assessed with venography and duplex ultrasound imaging. Cumulative patency curves were calculated. RESULT: Median age was 54 years (range, 14-76 years); female/male ratio was 2.8:1. Obstructions were primary in 141 limbs and postthrombotic in 89, and 29 required recanalization of occlusions. The C(4-6) rate and ratio of limbs with postthrombotic obstruction were significantly higher in group iY vs group DB (49% and 32% [P = .049]; 47% and 28% [P = .022], respectively). The median follow-up was 12 months (range, 1-108 months) in 107 patients (93%). The overall primary, assisted primary, and secondary patency rates at 4 years were 61%, 92%, and 98%, respectively. The distribution of occluded stent systems (n = 4) and frequency of reinterventions (n = 29) were reflected in the primary and secondary patency rates for groups A, DB, and iY at 4 years (77% and 100%, 73% and 100%, and 41% and 90%, respectively). The frequency of reinterventions was significantly lower in group DB vs groups A and iY (8%, 32%, and 37%, respectively; P < .01). CONCLUSION: Chronic iliocaval confluence obstruction is best managed by double-barrel stenting when feasible. The apposition technique requires a high reintervention rate owing to restenosis of the unsupported segment. The secondary stent patency appears to be less in limbs with postthrombotic occlusion. Primary stent patency of nonocclusive obstruction was inferior in group iY regardless of etiology of obstruction. However, inverted Y fenestration is the only choice in delayed contralateral stenting or when the inferior vena cava is extensively involved. There is no optimal solution to the treatment of the iliocaval confluence presently, and the choice of technique is decided by the extent, site, and type of obstruction.

Unexpected major role for venous stenting in deep reflux disease.

BACKGROUND: Treatment of chronic venous insufficiency (CVI) has largely focused on reflux. Minimally-invasive techniques to address superficial and perforator reflux have evolved, but correction of deep reflux continues to be challenging. The advent of intravascular ultrasound (IVUS) scan and minimally invasive venous stent technology have renewed interest in the obstructive component in CVI pathophysiology. The aim of this study is to assess stent-related and clinical outcomes following treatment by iliac venous stenting alone in limbs with a combination of iliac vein obstruction and deep venous reflux. METHODS: A total of 528 limbs in 504 patients, ranging in age from 15 to 87, underwent IVUS-guided iliac vein stent placement to correct obstruction over an 11-year period. The etiology of obstruction was nonthrombotic in 196 (37%), post-thrombotic in 285 (54%) limbs, and combined in 47 (9%). Clinical severity class of CEAP was C3 in 44%, C(4,5) in 27%, and C6 in 25% of stented limbs. Deep venous reflux was present in all limbs, associated with superficial and/or perforator reflux in 69%. Reflux was severe in 309/528 (59%) limbs (reflux multisegment score > or = 3) and 224/528 (42%) limbs had axial reflux. Venography and other functional tests had poor diagnostic sensitivity to detect obstruction, which was ultimately diagnosed by IVUS. The IVUS-guided iliac vein stenting was the only procedure performed and the associated reflux was left uncorrected. RESULTS: There was no mortality; morbidity was minor. Cumulative secondary stent patency was 88% at 5 years; no stent occlusions occurred in nonthrombotic limbs. Cumulative rates of limbs with healed active ulcers, freedom of ulcer recurrence in legs with healed ulcers (C5), and freedom from leg dermatitis at 5 years were 54%, 88%, and 81%, respectively. Cumulative rate of substantial improvement of pain and swelling at 5 years was 78% and 55%, respectively. Quality of life improved significantly. Reflux parameters did not deteriorate after stenting. CONCLUSION: Iliac venous stenting alone is sufficient to control symptoms in the majority of patients with combined outflow obstruction and deep reflux. Partial correction of the pathophysiology in limbs with multisystem or multilevel disease can provide substantial symptom relief. Percutaneous stent technology in concert with other minimally-invasive techniques to address superficial and/or perforator reflux offers such partial correction in limbs with advanced CVI and complex venous pathology. Open correction of obstruction or reflux is now required only infrequently as a "last resort".

Iliac-caval stenting in the obese.

BACKGROUND: Chronic venous insufficiency (CVI) in the obese, often with severe clinical manifestations, is increasingly encountered in clinical practice. The association has drawn special interest as the pathophysiology may be different from that seen in the non-obese. The disease poses special management problems in the obese as traditional conservative measures are seldom effective. Iliac-caval venous stenting has been effective in CVI management but applicability in the obese raises concerns regarding stent compression, morbidity and efficacy. METHODS: Results of iliac-caval stenting in 101 limbs of 87 patients are presented. Clinical features, venous test results, and outcome after stenting are reported with comparison to select relevant features in the non-obese limbs (n = 1513) that were stented over the same 11 year period. RESULTS: Bilateral clinical manifestations CVI were twice as common in the obese subset compared with the non-obese (28% vs 14% respectively, P = .0007), the incidence increasing with BMI. Resting and exercise femoral vein pressures were similar to the non-obese. Obstructive lesions of primary or postthrombotic origin similar to those seen in non-obese limbs were detected by intravascular ultrasound examination in 89% of limbs. Compression by increased intra-abdominal pressure associated with obesity was likely the mechanism of obstruction in 11% of the limbs. Iliac-caval venous stenting was found to be safe with no mortality (<30 days), low morbidity (deep venous thrombosis in 3%), high patency (86% cumulative at five years), and satisfactory clinical outcome. Sixty-eight percent and 46% of limbs showed cumulative improvement in pain and swelling respectively at 5 1/2 years after stenting, with 65% and 31% limbs achieving complete relief of these respective symptoms. Thirty of 45 limbs (58% cumulative) were free of dermatitis/ulcer at four years. CONCLUSION: The mechanism of venous obstruction in the obese is substantially similar to those in the non-obese. Primary or post-thrombotic lesions as seen in non-obese CVI cases are present in 89% of cases per IVUS examination. Compression of the venous outflow by adiposity/abdominal pressure may be a factor in 11%. Iliac-caval venous stenting is a satisfactory clinical option in the obese with severe CVI manifestations requiring speedy relief.

Percutaneous recanalization of total occlusions of the iliac vein.

BACKGROUND: Venovenous bypass has been the standard in relieving chronic total occlusions of iliac veins. The technical feasibility of percutaneous recanalization was previously reported. Routine applicability of this technique in a wide spectrum of lesions and patients, stent patency, and clinical outcome forms the basis of this presentation. METHODS: During a 9-year period, 167 limbs in 159 unselected patients in a consecutive series with post-thrombotic chronic total occlusions of the iliac and adjacent vein segments underwent percutaneous attempts at recanalization. Patients were not selected based on venographic appearance or extent of the lesion, or excluded because of a preemptive choice of open venovenous bypass surgery. RESULTS: Percutaneous recanalization was successful in 139 of 167 limbs (83%), including patients with bilateral occlusions and 14 patients with inferior vena cava filters incorporated in the treated occlusion. Median age was 53 years (range, 18-84 years). Thrombophilia was identified in 44 patients. Venous dermatitis/ulcer was found in 46% of the treated limbs. Recanalization involved three or more totally occluded vein segments in 42% of the limbs. The cumulative secondary stent patency rate at 4 years was 66%. The cumulative marked relief of pain and swelling at 3 years was 79% and 66%, respectively. Cumulative healing of venous ulcer at 33 months was 56%. Quality of life metrics improved significantly. CONCLUSIONS: Most femoroiliocaval chronic total occlusions lesions can be successfully recanalized percutaneously with very little morbidity, minimal downtime, sustained long-term stent patency, and substantial clinical improvement. The procedure has wide applicability in a broad spectrum of symptomatic patients, including those with extensive lesions, and can be considered for routine use.

Reinterventions for nonocclusive iliofemoral venous stent malfunctions.

BACKGROUND: Percutaneous iliofemoral venous stenting has been shown to be effective, safe, and durable in both nonthrombotic iliac vein lesion (NIVL) and postthrombotic disease. A small fraction of stented limbs require reintervention to correct stent malfunction. This manuscript examines the reasons for reintervention, types of procedures performed, and outcome. METHODS: Femoro-ilio-caval stenting was performed in 1085 limbs over a 10 year period from 1997 to 2007 (NIVL/postthrombotic limb ratio 1:1). Reinterventions were required in 137 limbs (13%) for non-occlusive stent malfunction. RESULTS: Median time of reintervention after the initial procedure was 15 months. Primary indication for reintervention was stent abnormalities discovered on routine surveillance imaging in 31% of the limbs and residual/recurrent symptoms after initial stenting in 69% of the limbs. Prevalent symptoms before reintervention were swelling (45%), pain (18%), combination of pain and swelling (33%), and venous dermatitis/ulcer (15%). Seventy-seven percent of limbs required only a single reintervention and 23% required two or more interventions. The type of reintervention could be broadly categorized into four types: (1) cephalad stent extension to correct stent outflow problems; (2) caudad stent extension to correct inflow problems; (3) balloon dilatation of stent stenoses; and (4) combinations. The types of stent inflow/outflow lesions encountered were different in NIVL and postthrombotic limbs. In both groups, the external iliac vein segment had a greater incidence of pathology than other stented venous segments during reintervention. A denovo stenotic lesion of uncertain aetiology that occurred below an existing stent was also exclusive to the external iliac vein segment. Instent restenosis (ISR) occurred in both subsets. Two types of ISR were encountered: (1) a 'soft' lesion probably due to reduced flow channel lined by thrombus within the stent from inflow/outflow problems and (2) a 'hard' lesion that occurred independently, was resistant to dilatation and tended to recur unlike the 'soft' lesion. Cumulative improvement in pain and swelling at 18 months following intervention was 67% and 72%, respectively. Complete cumulative healing of venous dermatitis/ulcer was 90% at 12 months post reintervention. CONCLUSION: Venous stenting for chronic venous disease is largely trouble-free with only a small fraction of the stented limbs requiring reinterventions. Reinterventions were performed to correct previously overlooked or new defects in inflow, outflow and/or the stent. Reinterventions are worthwhile since they improve residual/recurrent symptoms in a durable fashion.

Venous stenting across the inguinal ligament.

BACKGROUND: Arterial stenting across joints is not recommended because of increased risk of in-stent focal neointimal hyperplasia and compression or fracture of the stent by joint motion with decreased long-term patency. The aim of this study was to assess the risk of placing stents in the venous system across the inguinal ligament. MATERIALS AND METHODS: From 1997 to 2006, 177 limbs with chronic non-malignant obstructive lesions had stents placed in the iliofemoral venous outflow across the inguinal ligament into the common femoral vein. Transfemoral venograms and duplex ultrasound scans to assess cumulative patency rates, cumulative rates, site of in-stent restenosis (ISR), and structural integrity of the stents were performed during follow-up. The results were compared to the findings in 316 limbs with stents terminating cephalad to the inguinal ligament. RESULTS: Overall cumulative secondary patency (CSP) rate at 54 months was greater in the limbs with cephalad than in those caudad stent termination in relation to the inguinal ligament (95% and 86%, respectively; P = .0001). Although CSP of limbs with non-thrombotic obstruction was 100% regardless of the site of stent termination, that of the limbs stented for thrombotic obstruction was greater for stents terminating cephalad than for those caudad to the ligament (90% and 84%, respectively; P = .0378). However, a comparison of CSP rates between limbs treated for thrombotic occlusion and those with thrombotic non-occlusive obstruction at 32 months revealed no difference whether or not the stent was placed across the inguinal ligament (occlusion 77% and 77%, P = .7540, non-occlusive obstruction 96% and 95%, P = .7437). Severe ISR (> or =50%) were rare, 5%. The cumulative rate was, however, not significantly different in limbs stented cephalad and caudad to the inguinal ligament (7% and 11%, respectively, P = .6393). Focal in-stent recurrent stenosis at the site of the inguinal ligament occurred in only 7% of limbs (all <50%). None of the braided stainless steel stents were compressed or fractured. CONCLUSION: Contrary to arterial stenting, braided stainless stents can be safely placed in the venous system across the inguinal crease with no risk of stent fractures, narrowing due to external compression, focal development of severe in-stent restenosis, and no effect on long-term patency. The patency rate is not related to the length of stented area or the placement of the stent across the inguinal ligament, but is dependent upon the etiology and whether the treated postthrombotic obstruction is occlusive or non-occlusive.

Chronic deep venous obstruction: definition, prevalence, diagnosis, management.

Ilio-caval venous obstruction has an important role in the expression of symptomatic chronic venous disease regardless of aetiology. The presence of obstruction has been more or less previously ignored and emphasis placed on reflux alone. Stenting of the ilio-femoral veins guided by intravascular ultrasound (IVUS) can now be performed with low morbidity and mortality using appropriate technique. Current diagnostic modalities do not allow a definitive assessment of haemodynamically critical venous obstruction, which hampers selection of limbs for treatment. The diagnosis must be based on morphological studies (preferably IVUS) in patient selected with specific history, signs and symptoms. A high index of suspicion and generous use of morphological investigations are critical in the initial recognition of venous outflow obstruction. Stenting of the ilio-femoral vein appears to be durable with a substantial improvement in limb pain and swelling, high rate of ulcer healing, enhanced quality of life and decreased disability. The beneficial clinical outcome occurs regardless of the presence of remaining reflux, adjunct saphenous procedures or aetiology of obstruction.

Stents for chronic venous insufficiency: why, where, how and when--a review.

Venous stenting has introduced a minimally invasive and safe technique that can be performed on an outpatient basis with little downtime for the patient. It is applicable in a wide spectrum of patients with chronic venous disease with disabling symptoms. Long-term patency and clinical outcome are excellent even when associated reflux is present and left untreated. The need for open surgery to correct reflux or obstruction has been drastically reduced; however, such procedures can still be carried out later in the event of stent occlusion or failure to relieve symptoms.