Strategies for the Management of SVC Stent Migration into the Right Atrium

Unexpected coil mass migration during transvenous embolization of a dural arteriovenous fistula resolved with guidewire-assisted snaring technique

Endovascular embolization is a standard treatment for dural arteriovenous fistulas (dAVFs). Although it is considered relatively safe, intraoperative and postoperative complications can occur. Herein, a rare case of unexpected coil mass migration requiring a retrieval procedure during sinus occlusion for a transverse-sigmoid sinus dAVF (TSdAVF) is described. An 83-year-old man presented with worsening decline in cognitive function. Magnetic resonance angiography showed a TSdAVF. Since his symptoms seemed to be a result of the TSdAVF, transvenous embolization preserving the normal cranial venous circulation was planned. During sinus occlusion, including embolization of the shunted pouch of the TSdAVF, unexpected migration of the coil mass to the confluence of the superior sagittal sinus and the transverse sinus occurred. The migrated coil mass impeded venous circulation in the superior sagittal sinus. Since the presence of the coil mass at the confluence could have had catastrophic sequelae, the coil mass was retrieved using a guidewire-assisted snaring technique. Sinus occlusion was subsequently completed with repositioning of the coil mass at the target site. The TSdAVF resolved, with no recurrence confirmed for 1 year. Clinicians should be aware that coil mass migration can unexpectedly occur during sinus occlusion performed for treatment of a TSdAVF. The guidewire-assisted snaring technique might be effective in resolving this intraoperative complication.

Stent migration as complication of endovascular treatment of vascular access stenosis: A systemic review

Outflow vein stenosis is one of the commonest complications of both native and prosthetic vascular access. Together with angioplasty, first-line treatment is stenting. Although it has been described as a uncommon complication, the risk of stent migration should be always considered. We aimed to conduct a systematic review of literature concerning stents migration in vascular access, the possible outcomes and treatments. This study was performed applying Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches were conducted in PubMed/Medline, Scopus, and Google scholar databases. Studies selection, data abstraction was done by two different reviewers. We identified 17 studies, comprising 18 cases (M:F 1:1, mean age 56 ± 18 (range 33-88)). All the patients underwent stenting for vascular access outflow stenosis. The commonest type of device reported was self expandible bare-metal stent. Intraoperative evidence of stent migration occurred in six cases at the final quality control, or for intraprocedure dyspnea onset. In two patients it was a incidental diagnosis. In the remaining cases, chest pain or dyspnea were the common delayed presentation symptoms. Even if stent migration is an uncommon event, it is burdened with low mortality and morbidity. Literature provide only few and frequently inadequate data. Stent removal is the treatment of choice when severe symptoms or cardiopulmonary complication are present. Endovascular procedures demonstrated to be an effective and safe alternative, while open surgical treatment is preferred whenever endovascular therapy failed or in selected cases.

Small Oversized Stent Graft Is Associated With Increased Patency for the Treatment of Central Venous Disease in Hemodialysis Patients

PURPOSE

The purpose of this study was to identify the independent predictors of higher patency rates and investigate the selection of specifications of stent graft in the treatment of central venous disease.

MATERIALS AND METHODS

This retrospective study included 54 patients who underwent stent-grafts' placement for the treatment of central venous disease between March 2017 and September 2022 at a tertiary hospital. The demographic data for the patients and the clinical data of the treated lesions were collected and analyzed. The patency rates of the treated lesions with different oversizing range were calculated via the Kaplan-Meier and log-rank analyses. The multivariate Cox proportional hazard models were constructed to identify the independent predictor of the target site primary patency.

RESULTS

The median follow-up period was 21.5 months. The primary patency rates of the target sites were 90.7%, 72.2%, and 55.1% at 6, 12, and 24 months, respectively. The assisted primary patency rates of the lesions were 96.3%, 92.5%, and 80.3% at 6, 12, and 24 months, respectively. The log-rank analysis showed that the stent-grafts' placement with small oversizing had significantly higher primary patency rates than those with large oversizing (p=0.022). The multivariate analysis revealed that concomitant stenosis and large oversizing stent graft were the independent predictors of target site primary patency.

CONCLUSIONS

Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing.

CLINICAL IMPACT

Stent grafts showed reasonable primary patency for the treatment of central venous disease in hemodialysis patients. Few studies, however, have explored the efficiency of stent grafts to treat CVD by considering different factors such as sizing considerations, the rate of oversizing percentage, etc. A stent graft with small oversizing is associated with better target site primary patency rates than those with large oversizing. Excessive oversizing should be avoided to prevent infolding or stent collapse.

Superior Vena Cava Syndrome: Etiologies, Manifestations, and Treatments

Superior vena cava (SVC) obstruction, whether from benign or malignant causes, results in a variety of symptoms. It is a potential medical emergency when cerebral or laryngeal edema occurs. Endovascular therapy is the treatment of choice for patients in need of emergent relief of symptoms. This article will provide a review of SVC syndrome with a focus on endovascular treatment techniques.

Application of kissing technique for the treatment of superior vena cava syndrome

OBJECTIVES

Superior vena cava syndrome is a series of symptoms caused by compression of the superior vena cava and its main branches. Endovascular therapy is now widely accepted because it offers rapid, safe and effective relief of clinical symptoms. Few reports have described the application of kissing technique for the treatment of superior vena cava syndrome. In this report, we review a series of cases in which superior vena cava syndrome was treated by kissing technique and we share our experience.

METHODS

Our institute treated 22 patients with SVCS by endovascular intervention from November 2016 to June 2021; among them, the kissing technique was used in 10 cases and achieved satisfactory results. This is a retrospective evaluation and analysis of 10 patients with superior vena cava syndrome who were treated by endovascular intervention using the kissing technique from May 2018 to April 2021 in Hwa Mei Hospital, University of Chinese Academy of Sciences. Based on literatures, we summarize the diagnosis, treatment, and surgical experience.

RESULTS

All patients underwent the implantation of the kissing stents, and the technical success rate was 100%. The symptoms and signs of intravenous obstruction in all patients were alleviated or disappeared within one to three days after the procedure. During the follow-up period, nine patients remained free from any clinical signs or symptoms, and one patient died one month after the procedure due to the progression of malignant tumors.

CONCLUSION

As a palliative intervention, the kissing technique for the treatment of superior vena cava syndrome caused by malignant tumors is safe, rapid, and effective. Successful endovascular therapy can quickly relieve symptoms, improve the patient's quality of life, and provide more opportunities for subsequent anti-tumor treatment.

A review of the incidence, outcome and management of venous stent migration

INTRODUCTION

Percutaneous endovenous stenting has emerged during the last decade as the primary method of treating symptomatic venous outflow obstruction. A recognised complication of venous stenting is stent migration. The aim of this systematic review was to identify the number of cases reported in the published literature describing stent migration, to recognise risk factors that may be associated with this complication, and outcomes following migration.

METHODS

A review was conducted following MOOSE and PRIMSA guidelines and registered on PROSPERO. MEDLINE, EMBASE, and PubMed databases and key references were searched using specified keywords. All relevant data for primary procedure and subsequent presentation with stent migration was retrieved. Data was assessed as too low quality to allow for statistical analysis.

RESULTS

Between 1994 and 2020, 31 articles were identified comprised of 29 case reports and 2 case series providing data for 54 events of venous stent migration with 47/54 providing some data for stent used. Mean age of patients in who migration occurred was 50 years (range 19-88) and 57.6% (n=30) were male. Most reported cases were 60mm or less in length (38/46, 82.6%) and only 3 of the reports were stents greater than 14mm in diameter (3/47, 3.6%). None of the papers reported migration of stents of more than 100mm in length. In 85% of the migrated stent events, retrieval was attempted with 56% via an endovascular approach. The immediate outcome was satisfactory in 100% of the reported attempts whether by endovascular or open surgical approaches.

CONCLUSIONS

This literature review would suggest that the risk of migration is rare but may be underreported. The majority of reported cases are shorter and smaller diameter stents. The paucity of published data and the short term follow up provided suggest more formal data collection would provide a truer reflection of incidence however clear strategies to avoid migration need to be followed to prevent this complication from occurring.

Migration of covered stents in thoracic central vein obstruction procedures in patients with hemodialysis: Case report and literature review

OBJECTIVE

The objective of the study is to present a case of hemodialysis in which the covered stent that had migrated into the right ventricle was retrieved by exploratory thoracotomy, and to review the literature on the diagnosis and treatment of stent migration in thoracic central vein obstruction (TCVO) procedures for hemodialysis patients.

METHOD

A systematic search of the PubMed database was performed to identify clinical presentations, imaging strategies, stent types, and treatment modalities for stent migration in hemodialysis patients.

RESULTS

A total of 14 case reports on stent migration in TCVO procedures for hemodialysis patients were included and analyzed. Ten cases included migration to the cardiac chambers and the remainder migration to the pulmonary artery. The common symptoms of stent migration in TCVO procedures are reported to be chest pain and dyspnea, while three of the cases studied involved no symptoms. Echocardiography, chest X-ray, and computed tomography are the commonly used methods for the diagnosis of stent migration and identification of the precise positioning of the stent. Stent migration to the right subclavian or innominate veins was the most prevalent case (seven cases). All were bare stents. Seven cases involved retrieval by interventional surgery, while four cases involved retrieval by open heart surgery. However, there were three cases in which the "wait-and-see" approach was adopted since the patients were asymptomatic.

CONCLUSIONS

Stent migration in TCVO procedures is a rare but extremely serious complication. The causes are not fully understood. The current treatment strategies include interventional surgery, open heart surgery, and the "wait-and-see" approach.

Endovascular Stenting for Malignant Obstruction of Superior Vena Cava: A Single-Center Experience Using the Body Floss Technique

Purpose Endovascular stenting is the treatment of choice for malignant obstruction of the superior vena cava (SVC) when rapid symptomatic relief is desired. Body floss technique is not routinely used during SVC stenting but has few advantages over single-access technique. We report our experience with stenting for malignant obstruction of the SVC using the body floss technique.

Materials and Methods Between March 2015 and March 2020, 25 patients (20 men, 5 women; median age, 65 years) with malignant SVC obstruction underwent endovascular stenting of the SVC. We retrospectively evaluated these patients for clinical and technical success rates, complications, recurrence-free survival, and overall survival.

Results Stent placement was successful in 24/25 patients (technical success: 96%). Clinical success was achieved in 23/25 (92%) patients. A mortality rate of 4% (1/25) was noted due to SVC rupture. Partial stent migration was noted in two patients (8%) and was treated by placing an additional overlapping stent. Incidental early stent thrombosis was seen in two patients within 8 hours of stent placement, but these patients showed symptom relief with anticoagulation. Follow-up imaging confirmed stent patency in all patients. Late stent occlusion due to tumor progression was seen in one patient. The primary patency rate was 88% (22/25). Overall median survival of 133 days was observed (range: 1–847 days).

Conclusion Endovascular stenting of the SVC for malignant obstruction using the body floss technique is associated with high technical and clinical success, and low rate of complications.

Results of Stenting for Central Venous Occlusions and Stenoses in the Hemodialysis Patients

Objectives: We aim to investigate the results of stenting for central venous occlusions and stenoses in the hemodialysis patients.

Methods: Twenty-nine cases treated with endovascular recanalization with deployment of bare metal stent (BMS) for central venous occlusions (24 cases) and recurrent stenoses (5 cases) between 2014 and 2018 were retrospectively analyzed. Results of these procedures including success rate, operative time, estimated blood loss, morbidity, primary patency, assisted primary patency and freedom from target-lesion revascularization (TLR) were evaluated.

Results: Nine lesions were in brachiocephalic vein (Occlusion/Stenosis: 8/1) and 20 lesions were in subclavian vein (Occlusion/Stenosis: 16/4). Procedural success was 94% (29/31 cases) and operation time/estimated blood loss was 68±39 min/28±54 g. Symptom were relieved or disappeared in all successful cases. Morbidity (extravasation of contrast medium) was 3% (1/29). During the period of observation, 1 stent fracture with occlusion and 1 stent migration to periphery were recognized. 1-year primary patency, freedom from TLR, and assisted primary patency were 40% (median patent time: 256 days), 67% (median patent time: 524 days), and 77%, respectively.

Conclusion: Stenting for central venous occlusions and stenoses in the hemodialysis patients is safe and durable treatment option. However, considering its off-label use and potential hazard including vessel rupture, stent migration, and stent fracture, the indication for BMS deployment should be conservative, and interventionist should be well acquainted with prevention and measures to these complications. (This is a translation of Jpn J Vasc Surg 2019; 28: 193–198.)

Bridging Stent Placement in Vena Cava Syndrome With Tumor Thrombotic Extension in the Right Atrium

Venous stent placement of symptomatic occlusion of the superior and inferior vena cava is considered the treatment of choice in malignant disease because this technique can restore patency and achieve a relief of symptoms. However, tumor thrombus extension into the right atrium harbors the potential risk of stent migration and perforation. One strategy to avoid this potential life-threatening complication could be the placement of a bridging stent from the superior vena cava-to-inferior vena cava. This case reports describes the superior vena cava-to-inferior vena cava bridging stent technique in 2 patients with malignant occlusion of the superior and inferior vena cava. Special considerations such as technical details of the devices and potential complications are discussed.

Superior Vena Cava (SVC) Endovascular Reconstruction with Implanted Central Venous Catheter Repositioning for Treatment of Malignant SVC Obstruction

Superior vena cava (SVC) syndrome is a group of clinical signs caused by the obstruction or compression of SVC and characterized by edema of the head, neck, and upper extremities, shortness of breath, and headaches. The syndrome may be caused by benign causes but most of the cases are caused by lung or mediastinal malignant tumors. Stenting of SVC has become widely accepted as the palliative treatment for this condition in malignant diseases, as it offers rapid relief of symptoms and improves the quality of life. Preserving previously placed central venous catheters (CVCs) is a major issue in this population. We report the case of a patient with SVC syndrome caused by tumoral obstruction due to central small-cell lung cancer who had right subclavian implanted CVC and a preferential head and neck venous drainage through the left internal jugular and brachiocephalic vein (BCV). We describe a complex procedure of SVC reconstruction with two different objectives: left recanalization and stent placement to ensure head and neck venous drainage and right BCV stenting for CVC repositioning and subsequent replacement. We also review published cases of SVC obstructions stenting with catheter repositioning. The patient experienced quick relief of symptoms after treatment. Chemotherapy was rapidly delivered through the preserved implanted CVC access. A 3-month follow-up computed tomography showed stents patency.

Central Venous Interventions

Central venous stenosis or occlusion is a common and vexing problem in patients undergoing hemodialysis. Typical presenting symptoms include arm swelling and prolonged bleeding after hemodialysis. Despite multiple treatment approaches, these stenoses tend to recur and progress over time. A thorough preprocedure evaluation, methodical procedural approach and awareness of potential complications are all essential to try to preserve vascular access and improve patients' quality of life.

Stent Migration and Bail-out Strategies

Stent migration is an inherent complication of stent deployment. A number of factors are responsible for this dreaded complication. The stent may eventually migrate to the heart or lungs or in the process of migration damage structures en route to its final destination. A number of techniques are available to bail out interventionalists if such a situation should arise. Occasionally a wait and watch approach may be prudent.

Technical and Anatomic Factors Influencing the Success of Inferior Vena Caval Stent Placement for Malignant Obstruction

PURPOSE

To evaluate the outcomes of inferior vena cava (IVC) stent placement for malignant obstruction and to identify anatomic and procedural factors influencing technical and clinical success.

MATERIALS AND METHODS

A total of 57 patients (37 male, 20 female; age range, 22-86 y) underwent 62 IVC stent placement procedures using 97 stents (47 Wallstents, 15 S.M.A.R.T. stents, 18 Wallflex stents, 17 others) from 2005 to 2016 for malignant IVC obstruction caused by hepatic metastases (n = 22; 39%), primary hepatic malignancy (n = 16; 28%), retroperitoneal metastases (n = 16; 28%), or other primary malignancy (n = 5; 9%). Presenting symptoms included lower-extremity edema (n = 54; 95%), ascites (n = 28; 50%), and perineal edema (n = 14; 25%). Sixteen percent (n = 10) and 10% (n = 6) of the procedures involved tumor and bland thrombus, respectively.

RESULTS

Stent placements resulted in 100% venographic patency and significantly decreased pressure gradients (P < .0001). Lower-extremity swelling, perineal swelling, and abdominal distension improved within 7 days in 83% (35 of 42), 100% (9 of 9), and 40% (6 of 15) of patients, respectively, and at 30 days after the procedure in 86% (25 of 29), 89% (8 of 9), and 80% (4 of 5) of patients, respectively. Increased pre- and post-stent placement pressure gradients were associated with worse outcomes. A 4% stent misplacement rate (4 of 97) was related to the use of Wallstents with caudal stent tapering, asymmetric deployment superior to the obstruction, suprahepatic IVC involvement, and decreased stent adherence to the IVC wall as a result of local mechanical factors.

CONCLUSIONS

Stent placement is reliable, rapid, and durable in improving malignant IVC syndrome. Understanding of technical and anatomic factors can improve accuracy and avoid complications of stent misplacement.

Hybrid treatment of an aortic pseudoaneurysm arising at the innominate artery junction secondary to superior vena cava stenting

Pseudoaneurysm of the innominate artery secondary to superior vena cava stenting has never been reported. We report the case of a 42-year-old woman previously treated for a Masaoka stage III thymoma with superior vena cava replacement through median sternotomy followed by adjuvant radiation therapy. Four years later, the patient came back with a large pseudoaneurysm at the junction of the innominate artery and ascending aorta. To avoid resternotomy, endovascular deployment of a stent graft in the ascending aorta with a periscope stenting in the left common carotid artery after axilloaxillary bypass was performed to treat this aortic pseudoaneurysm.

Superior Vena Cava Syndrome: Role of the Interventionalist

Superior vena cava syndrome results from the obstruction of blood flow through the superior vena cava and is most often due to thoracic malignancy. However, benign etiologies are on the rise secondary to more frequent use of intravascular devices such as central venous catheters and pacemakers. Although rarely a medical emergency, the symptoms can be alarming, particularly to the patient. Traditionally, superior vena cava syndrome has been managed with radiotherapy and chemotherapy. But interventional endovascular techniques have made inroads that offer a safe, rapid, and durable response. In many cases, it may be the only reasonable treatment. Because of this, an approach to endovascular treatment of this condition must be in the armamentarium of the interventional radiologist. This review will provide the reader with an insight into the etiology, pathophysiology, and various management principles of superior vena cava syndrome. The focus will be on understanding the techniques used during various endovascular interventions, including angioplasty, stenting, and pharmacomechanical thrombolysis. Discussion will also be centred on possible complications and current evidence as well as controversies regarding these approaches.

Two dislodged and crushed coronary stents: treatment of two simultaneously dislodged stents using crushing techniques

Coronary stent dislodgement is a rare complication of percutaneous coronary intervention. We report a rare case of dislodgement of two intracoronary stents. On withdrawal of two balloon catheters, one with a guide wire was mechanically distorted from the left main (LM) to the proximal left anterior descending artery (LAD) while the other was dislodged from the LM to the ostial left circumflex artery. The stent in the LAD could not be retrieved into the guide catheter using a Goose neck snare, because it was caught on a previously deployed stent at the mid LAD. A new stent was quickly deployed from the LM to the proximal LAD, because the patient developed cardiogenic shock. Both stents, including a distorted and elongated stent, were crushed to the LM wall. Stent deployment and crushing may be a good alternative technique to retrieving a dislodged stent.

Successful coronary stent retrieval from the ascending aorta using a gooseneck snare kit

Coronary stent dislodgement is a rare complication of percutaneous coronary intervention. We report a case of stent dislodgement in the ascending thoracic aorta. The stent was mechanically distorted in the left circumflex artery (LCX) while being delivered to the proximal LCX lesion. The balloon catheter was withdrawn, but the stent with the guide wire was remained in the ascending thoracic aorta. The stent was unable to be retrieved into the guide catheter, as it was distorted. A goose neck snare was used successfully to catch the stent in the ascending thoracic aorta and retrieved the stent externally via the arterial sheath.

Surgical removal of endovascular stent after migration to the right ventricle following right subclavian vein deployment for treatment of central venous stenosis

Central venous stenosis or occlusion occurs in 11-50% of hemodialysis patients with prior subclavian vein cannulation and ipsilateral fistula or shunt. Most patients are asymptomatic but some require treatment to reduce the risk of thrombosis and improve inadequate hemodialysis pressure. In these cases, endovascular intervention, including ballooning and stenting, is a feasible strategy for selected patents. We report an unusual case of a 40-year-old man on hemodialysis that underwent endovascular stenting to treat right subclavian vein stenosis and experienced stent migration to the right ventricle, requiring surgical removal.

Massage-induced delayed venous stent migration

Catheter-directed therapies in chronic deep vein thromboses can help improve leg function by mechanically addressing residual obstruction in lower extremity or pelvic veins, although the reported use of stents in leg veins is relatively unusual. The author reports a case of this type with long-term patency and clinical success, culminating in asymptomatic delayed venous migration of a stent to the right atrium after 3 years. Open heart surgery was required to remove the embedded stent fragments. The attributed mechanism was deep tissue massage of the thigh.

Migration of superior vena cava stent

There has been a recent increase in the use of endovascular prostheses resulting in complex surgical and interventional complications not previously recognised. We report a case of Superior vena cava stenosis treated with a wallstent which migrated to the right atrium, necessitating a combined radiological and surgical approach to retrieve it.