European Journal of Cardiovascular Medicine

Chronic venous disease is a prevalent medical condition that can lead to considerable morbidity and mortality. The primary mechanism responsible for the progression to severe clinical manifestations is the development of venous hypertension. In most cases, venous hypertension arises due to obstruction of venous outflow, incompetence of venous valves, and/or failure of the venous pump mechanism. As a result, blood flow is abnormally redirected from the deep venous system to the superficial veins, leading to venous dilatation, localized tissue inflammation, fibrosis, and, in advanced cases, ulcer formation. (1) Venous obstruction may be classified as central, occurring closer to the heart, or peripheral, occurring further away, and can affect either the upper or lower extremities. Over the past decade, the incidence of symptomatic venous lesions has increased substantially. Patients with end-stage renal disease (ESRD) who have arteriovenous fistulas (AVFs) are particularly affected, largely due to the increased use of long-term indwelling venous catheters in this population. It has been estimated that venous stenosis may develop in up to 40% of patients following subclavian or brachiocephalic vein catheterization. (2)

Iliocaval venous obstruction (ICVO) represents a clinicopathologic condition involving the systemic veins of the abdomen and may result from various etiologies. This condition can contribute to venous outflow obstruction, venous hypertension, and extensive lower extremity deep vein thrombosis (DVT). The central abdominal veins are located below the diaphragmatic caval opening at the level of the eighth thoracic vertebra and include the intrahepatic and infrahepatic segments of the inferior vena cava (IVC), as well as the common, external, and internal iliac veins. (3-4)

Endovascular intervention has significantly transformed the management of venous occlusive disease, including both thoracic central venous obstruction (TCVO) and ICVO. These minimally invasive techniques have evolved to become the standard of care and are now considered the first-line treatment for patients with moderate-to-severe symptoms related to thrombotic venous obstruction. Previous studies evaluating endovascular therapies have reported primary patency rates ranging from 10% to 30% at one year. (5-6)

The present study was conducted to assess clinical success, defined by symptomatic improvement, as well as patency rates following central and peripheral venous angioplasty and stenting in patients with symptomatic venous obstruction.

This prospective observational study was conducted at our tertiary cardiac care institute between January 2021 and December 2022. The study enrolled consecutive adult patients with symptomatic central or peripheral venous stenosis, including thoracic central venous occlusion (TCVO) and iliocaval venous occlusion (ICVO), who underwent endovascular treatment. The study was approved by institutional ethics committee (UNMICRC/CARDIO/2021/02). The written informed consent was obtained prior to endovascular intervention and angioplasty. All patients underwent a detailed clinical examination, and duplex ultrasonography was performed to confirm the diagnosis. The targeted upper or lower limb was thoroughly disinfected and draped under sterile conditions. In most cases, a combined approach using both radial artery and common femoral vein access was employed. The radial or brachial artery was selected based on the type of arteriovenous fistula (AVF), including radiocephalic, brachiocephalic, or brachiobasilic fistula with superficialization. Patients were included in the study if they were adults aged 18 years or older who presented with symptomatic central or peripheral venous stenosis or occlusion, including thoracic central venous occlusion or iliocaval venous occlusion, and were planned for percutaneous endovascular intervention. Eligible patients had symptoms clearly attributable to venous outflow obstruction, such as limb or facial swelling, venous hypertension, or vascular access dysfunction, with the diagnosis confirmed on appropriate imaging modalities including venography, CT venography, or duplex ultrasound. Only patients who underwent balloon angioplasty with or without stent placement and provided informed consent were enrolled. Patients were excluded if the venous lesion was detected incidentally in the absence of symptoms, or if they had acute deep vein thrombosis without evidence of underlying chronic venous stenosis. Those with prior surgical venous bypass for the same lesion, active systemic or access-site infection, significant coagulopathy precluding intervention, or a limited life expectancy due to severe nonvascular comorbidities were also excluded. Patients with incomplete clinical data or those who could not be followed up after the procedure were not considered for final analysis. Local infiltration anesthesia using 2–3 mL of 2% lidocaine was administered at the puncture site before arterial access using a 20 G needle. The Seldinger technique was utilized to insert a standard 6F, 11-cm sheath into the artery. Subsequently, the wires and introducers were withdrawn, and the sheath was gently pulled back until its tip was positioned just distal to the anastomosis in cases of transradial access for radiocephalic AVF, distal to the brachial anastomosis in brachiocephalic AVF, or distal to the anastomosis in brachiobasilic AVF. In selected cases, a 7F sheath was used to accommodate larger balloons for treating central venous lesions. The femoral vein was used as the second access site and was secured with short 7F–10F sheaths compatible with balloon and stent deployment. For ICVO interventions, vascular access was obtained under ultrasound guidance through the ipsilateral femoral vein, popliteal vein, great saphenous vein, or tibiofibular trunk, depending on the location of the lesion. Heparin (5000 IU) was administered through the sheath, followed by angiography to visualize the arterial system, AV anastomosis, and the venous stenotic segment. Angiography was performed through both access sites to determine the extent and length of the lesion. A fistulogram was conducted to evaluate the entire course of the fistula and to identify any lesions proximal to the central veins. If the fistula was patent, direct access through the fistula outflow was also considered, although this approach carries a small risk of missing inflow lesions. The stenotic segment was crossed using a 0.035-inch hydrophilic guidewire (Terumo, NJ, USA). In certain cases, lesions were traversed using both antegrade and retrograde approaches. The stiff end of the guidewire was occasionally required to cross resistant lesions. Subsequently, a standard 0.035-inch J-tip Terumo guidewire was advanced across the lesion, followed by passage of a 5F Judkins Right (JR) catheter to identify more proximal lesions. In selected cases, a long sheath such as a Mullins sheath (Cook Inc., Bloomington, IN, USA) was introduced via the femoral approach to provide better support for advancing balloons and stents. After successful traversal of the occlusion with the wire and catheter, balloon catheters of appropriate diameters were exchanged and gradually inflated to perform percutaneous transluminal angioplasty (PTA). Balloon diameters ranged from 1.5 to 10 mm, with burst pressures between 16 and 20 atmospheres, and balloon lengths ranged from 8 to 60 mm. The balloons used included ARMADA, ATLAS GOLD, ULTRAVERSE, among others. In two cases, satisfactory results were not achieved following balloon angioplasty, necessitating stent placement—one using an EPIC stent and the other with an ABSOLUTE PRO bare-metal stent. Following the intervention, the balloon catheter was withdrawn, and a completion angiogram was performed to assess for residual stenosis or thrombus and to confirm unobstructed flow to the central veins. Finally, the sheath was removed, and hemostasis was achieved using a compression bandage. Fig A Fig B Fig C Fig D Fig E Fig F Fig G Figure 1 (A)Initial venogram showed complete occlusion of left innominate vein Lesion (B) It was crossed using 0.035 Terumo anttrogradely (C) PTA was done using 12×40 armada balloon @ 10 ATM (D,E,F) Post PTA venogram showed residual stenosis more than 50% and hence again dilated with 14×40 ballon. (G) Final venogram showing adequately dilated innominate vein. Fig A Fig B Fig C Figure 2. left lower limb PVG showing stenosis in CIV (fig A) Ballon dilatation done with PTA ballon ATLAS GOLD 16×40 (fig B) , Post dilatation venogram showing adequate dilatation of CIV with no residual stenosis (fig C) Definitions Technical success was defined as successful completion of the procedure with no procedural complications, a luminal diameter improvement greater than 50%, and absence of significant residual stenosis. Technical failure referred to the inability to cross or adequately dilate the target lesion. Early failure was defined as failure to cross the lesion during the index procedure or development of occlusion or ≥50% restenosis within 30 days of the intervention. A complication was considered any unexpected event requiring endovascular or surgical management within 30 days following the procedure. Residual stenosis was defined as a luminal narrowing of ≥30% compared with the adjacent normal venous segment. Post-procedural clinical response was categorized as complete (absence or minimal residual symptoms or edema), partial (clinical improvement with moderate residual symptoms or edema), or minimal (no significant change in symptoms or edema). Patency was assessed through patient history, physical examination, and Doppler ultrasonography. Suspected venous reocclusion was further evaluated using computed tomography or venography. Primary patency referred to uninterrupted vessel patency without recurrent stenosis or need for reintervention. Primary-assisted patency described vessels that required repeat intervention to maintain patency without progression to thrombosis. Secondary patency was defined as maintained vessel patency following additional endovascular intervention after documented reocclusion. Statistical Analysis The study data were compiled and recorded using Microsoft Excel 2010 and subsequently exported to the data editor of the Statistical Package for the Social Sciences (SPSS), version 20.0 (Armonk, NY, USA: IBM Corp.). Frequency distribution was calculated for qualitative variables. Kaplan–Meier survival analysis was performed to determine primary and secondary patency rates. Statistical significance was considered at a p value < 0.05.

Table 1. Baseline characteristics of the study population.

The mean age of the study population was 46.65 ± 13.06 years. Males constituted 57.75% (n = 41) of the cohort, while females accounted for 42.25% (n = 30). Diabetes mellitus was present in 16.9% (n = 12) of patients, and hypertension was observed in 23.9% (n = 17). Chronic kidney disease was noted in 77.5% (n = 55) of participants, whereas obesity was present in 1.41% (n = 1).

Table 2: Clinical diagnosis of the study population

The majority of patients had post-AVF–related disease (74.65%, n = 53). Lower limb deep vein thrombosis was observed in 16.90% (n = 12) of cases, followed by Budd–Chiari syndrome in 5.63% (n = 4). Post–hemodialysis catheter–related pathology was identified in 2.82% (n = 2).

Table 3. Comparison of primary and secondary patency between TCVO and ICVO

Primary and secondary patency rates were evaluated at 1, 3, 6, and 12 months for patients with thoracic central venous obstruction (TCVO) and iliocaval venous obstruction (ICVO).

At 1 month, primary patency was achieved in 49 of 51 TCVO patients (96%) and in all 17 ICVO patients (100%). Secondary patency at this time point was 100% in both groups. By 3 months, primary patency had decreased to 82% (42/51) in the TCVO group, while it remained 100% in the ICVO group. Secondary patency at 3 months was 96% (49/51) for TCVO and 100% for ICVO.

At 6 months, primary patency further declined to 66% (34/51) in TCVO patients and 82.3% (14/17) in ICVO patients. Secondary patency remained high at 96% (49/51) in TCVO and 88.2% (15/17) in ICVO.

At 12 months, primary patency was 60.8% (31/51) in the TCVO group and 82.4% (14/17) in the ICVO group. Secondary patency rates were 94.1% (48/51) for TCVO and 88.2% (15/17) for ICVO.

Overall, while primary patency declined over time, secondary patency remained relatively high in both groups, with ICVO patients generally maintaining higher primary patency compared to TCVO patients.

Fig.3. Line graph showing primary patency rates within the 1,3,6 and 12-month follow-up examination in two subgroups respectively.

Fig.4. Line graph showing secondary patency rates within the 1,3,6 and 12-month follow-up examination in two subgroups respectively

Fig 5. Line graph showing cumulative primary and secondary patency rates within the 1,3,6 and 12-month follow-up examination.

In our study we found significant difference between primary patency (log rank =0.03) of TCVO and ICVO group. No significant difference between secondary patency (log rank =0.938) of two groups. So, primary patency is better in ICVO group.(Fig.6,7)

Fig .6. Kaplan-Meier curve showing primary patency rate in percentages and time in months. P values calculated with the log-rank test. Significant difference between primary patency of TCVO and ICVO group. (Log rank P=0.03)

Fig .7. Kaplan-Meier curve showing secondary patency rate in percentages and time in month. P values calculated with the log-rank test. No significant difference between secondary patency of TCVO and ICVO group. (Log rank P=0.938)

In our study we found significant difference between primary patency (log rank =0.04) of antiplatelet and anticoagulant group. No significant difference between secondary patency (log rank =0.738) of two groups. So, primary patency is better in patients receiving anticoagulant on discharge.(Fig .8,9)

Fig .8. Kaplan-Meier  curve showing  primary patency rate in percentages and time in months. P values calculated with the log-rank test. Significant difference between primary patency of antiplatelet only and anticoagulant group. (Log rank P=0.03)

Fig.9.Kaplan-Meier curve showing secondary patency rate in percentages and time in month. P values calculated with the log-rank test. No significant difference between secondary patency of antiplatelet only and anticoagulant group. (Log rank P=0.938)

In our study only two patients undergone stenting. one patient lost primary patency at 6 months and undergone reintervention and both have 100% secondary patency rate till 12 months. Both groups are not comparable in our study because of very small number of stenting group.

Total reintervention in a year among 68 patient in  is 35 so average 0.5 reintervention  per year needed by each patient to maintain patency.so every  next patient need one  reintervention in a year.

In the present study, percutaneous endovascular intervention demonstrated a high technical success rate and acceptable short-term patency outcomes in patients with symptomatic central and peripheral venous obstruction. The study population largely comprised middle-aged patients with a high burden of chronic kidney disease and prior vascular access, reflecting real-world clinical practice where venous stenosis is frequently access-related. The majority of lesions were central venous in location, most commonly involving the innominate and subclavian veins, and limb swelling with or without arteriovenous fistula dysfunction was the predominant indication for intervention. Plain balloon angioplasty remained the primary treatment modality, achieving successful luminal gain in more than 94% of patients, with stenting reserved for a small subset with residual stenosis. Overall, the low complication rate and high procedural success underscore the safety and feasibility of percutaneous venous interventions in this high-risk cohort during short-term follow-up.

In our study, the initial technical success rate was 94%, which is consistent with previously published literature on endovascular management of venous stenosis. Reported technical success rates have varied across studies, ranging from moderate to high. Glanz et al. (7) reported an initial success rate of 76%, while Beathard et al. (8) achieved a success rate of 94%, defined as ≥80% luminal dilatation. Chen et al. (9) documented a comparatively lower technical success rate of 70.97%. In contrast, Sprouse II et al. (10) reported a 100% technical success rate with no procedure-related complications. The high success rate observed in our study further supports the efficacy and reliability of percutaneous venous interventions, even in a cohort with complex access-related and central venous lesions.

Oderich et al. (11) reported an initial clinical success rate of 89% (33 of 37 procedures), with no access-site–related complications such as hematoma, seroma, or infection. However, they observed a significantly higher complication rate following peripheral venous (PV) interventions compared with central venous (CV) interventions (4 of 15 vs. 0 of 50; P < .05). The reported complications included venous dissections involving the basilic and cephalic veins and one case of cephalic vein rupture during balloon dilatation. In contrast, our study demonstrated a low complication rate, with only minor and manageable procedure-related adverse events. During short-term follow-up, the majority of our patients experienced marked symptomatic improvement, particularly with respect to pain and limb swelling, which were the primary indications for intervention. Consistent with prior reports, including those by other investigators, we observed that while percutaneous transluminal angioplasty (PTA) for symptomatic central venous occlusive disease provides effective early symptomatic relief, its benefit is often temporary, necessitating repeat interventions to maintain long-term patency. (2,11-13)

In our study, the most common sites of central venous occlusion were the innominate vein, subclavian vein, and common iliac vein. This distribution is broadly consistent with previously published series, although variations exist depending on patient population and underlying etiology. Sprouse II et al. (10) reported central venous stenosis or occlusion most frequently involving the brachiocephalic vein and superior vena cava, with fewer cases affecting the subclavian vein. Similarly, Mehmet Burak et al. (14) observed the subclavian vein as the most commonly involved site, followed by the innominate vein, axillary vein, and superior vena cava. These differences likely reflect heterogeneity in vascular access history, catheter use, and the proportion of hemodialysis-dependent patients across studies.

The optimal postprocedural antithrombotic strategy following endovenous treatment of central venous obstruction remains uncertain. Eijgenraam et al. (15) and Meissner et al. (16) recommend short-term antithrombotic therapy after intervention; however, robust evidence guiding the choice, combination, and duration of antiplatelet or anticoagulant therapy is lacking. To date, no randomized controlled trials have established standardized postintervention antithrombotic regimens for thoracic central venous obstruction, resulting in considerable variability in clinical practice. Our findings, demonstrating improved primary patency in patients discharged on anticoagulation, add to the growing but still limited body of evidence suggesting a potential role for anticoagulant therapy in selected patients.

Several studies have highlighted the challenge of maintaining long-term patency following percutaneous venous interventions, particularly in patients with hemodialysis access. Nael et al. (17) reported primary patency rates of 81%, 46%, and 22% at 1, 6, and 12 months, respectively, with significantly improved assisted patency rates following reintervention. Similarly, Asif et al. (18) observed poor primary patency at 6 and 12 months but excellent secondary patency with repeat interventions. Glanz et al. (7) reported declining patency over time, with a 1-year patency rate of 35% and a 2-year rate of only 6%. These findings underscore that while angioplasty is effective in restoring venous outflow, restenosis remains common and often necessitates repeated procedures.

In contrast, some studies have demonstrated more favorable outcomes, particularly with stent placement. Williams et al. (19) reported median primary, assisted primary, and secondary patency rates of 71%, 89%, and 91%, respectively, over a median follow-up of nearly two years. Lichtenberg et al. (20) observed a cumulative primary stent patency of 100% at 12 months, while Razavi et al. (21) reported a 1-year primary patency rate of 84%, with superior outcomes in nonthrombotic compared with post-thrombotic lesions. In addition to anatomical patency, Razavi et al. (21) demonstrated significant clinical improvement, with nearly two-thirds of patients showing a meaningful reduction in Venous Clinical Severity Score at 12 months.

In our study, only two patients underwent venous stenting, limiting meaningful comparison between angioplasty and stent groups. This limitation is consistent with findings from Bakken et al. (22), who reported no significant difference in primary or assisted primary patency between percutaneous transluminal angioplasty and primary stent placement. Given the small number of stented patients in our cohort, conclusions regarding the superiority of one strategy over the other cannot be drawn.

Overall, while percutaneous venous interventions demonstrate high technical success and provide rapid symptomatic relief in the short term, durability remains a key concern. The need for repeat interventions, particularly within the first year, highlights the chronic and recurrent nature of venous occlusive disease. Emerging technologies, including drug-eluting balloons and stents, may offer improved long-term patency by reducing restenosis, but further studies are required. Careful patient selection, individualized postprocedural antithrombotic therapy, and close surveillance—especially during the first six months after intervention—are essential to optimize outcomes and preserve venous patency over time.

Limitations

This study has certain limitations that should be considered while interpreting the results. Being a single-centre experience, the findings represent a relatively limited patient population and may not be universally generalizable. Larger studies involving multiple centres, a wider range of venous occlusive conditions, and longer follow-up periods are needed to better define the role of percutaneous transluminal angioplasty and stent placement in chronic venous occlusion.

Another important limitation is that venous patency was not assessed using objective imaging methods in all patients during follow-up. However, the primary aim of these interventions is relief of symptoms, and clinical improvement remains the most meaningful indicator of procedural success. Primary assisted patency could not be calculated, as repeat interventions were undertaken only in patients who returned with symptomatic complete thrombosis.

The present report reflects our early experience, with a relatively small sample size and short-term follow-up, which limits assessment of long-term outcomes, particularly in the Indian population. In addition, there is currently a lack of clear guidelines regarding the choice and use of balloons or stents for venous interventions, largely due to the limited global experience with these procedures.

Post-procedure medical therapy also remains an area of uncertainty. The optimal strategy regarding antiplatelet versus anticoagulant therapy, especially the duration and role of long-term anticoagulation after venous interventions, is yet to be clearly established. Despite these limitations, we believe that our findings provide a practical and realistic picture of outcomes that can be expected in routine clinical practice.

Percutaneous interventions for symptomatic central and peripheral venous stenosis offer an effective and minimally invasive option for achieving short-term symptom relief and functional improvement. These procedures are associated with high technical success rates, low procedural morbidity, and rapid recovery, making them particularly valuable for patients with complex venous outflow obstruction. However, restenosis continues to be a concern, highlighting the need for careful clinical follow-up and long-term surveillance. As experience with venous interventions continues to expand, further studies with larger patient cohorts and longer follow-up durations are essential to refine treatment strategies, standardize procedural approaches, and define optimal post-procedural medical management. Such data will help strengthen the evidence base and guide the future management of venous stenotic and occlusive disease.

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