Interventional therapies in acute pulmonary embolus-current trends and future directions.

Venous thromboembolic disease presenting with acute pulmonary embolus (PE) can be treated in a variety of ways from anticoagulation as an outpatient to surgical embolectomy with many new interventional therapies being developed. Mortality in these patients can be as high as 50% and many of these treatments are also considered to be high risk. Early involvement of a multidisciplinary team and patient risk stratification can aid management decisions in these complex patients who can suddenly deteriorate.In this review, we summarise the evidence behind new and developing interventional therapies in the treatment of high and intermediate-high risk PE including catheter-directed thrombolysis, pharmacomechanical thrombolysis, thromboaspiration and the growing role of extracorporeal membrane oxygenation in the stabilisation and management of this cohort of patients.

Catheter directed thrombolysis for a pulmonary arterial thrombus on VA ECMO in a child - a case report.

INTRODUCTION: Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) as a bridge to cardiac transplantation is considered a high risk support strategy in the paediatric population. METHODS: We describe the case of a 12 year old boy who required V-A ECMO support for rapidly deteriorating cardiomyopathy and developed a massive pulmonary embolus (PE) peri-cannulation. Subsequent investigations were also positive for heparin induced thrombocytopenia. RESULTS: We elected to treat the PE with ultrasound accelerated catheter directed thrombolysis using the advantages of this minimally invasive targeted method to try and resolve the PE and avoid a cerebral haemorrhage, both of which would have taken the patient off the urgent transplant list. CONCLUSION: The PE resolved in 24 h and he went on to receive a cardiac transplant and have a favourable outcome.

Dialysis Access Maintenance: Plain Balloon Angioplasty.

Plain balloon angioplasty remains the first-line treatment for dialysis access stenosis. This chapter reviews the outcomes of plain balloon angioplasty from cohort studies and comparative studies. Angioplasty outcomes are more favourable in arteriovenous fistulae (AVF) compared to arteriovenous grafts (AVG) with primary patency at 6 months ranging from 42-63% compared to 27-61%, respectively, and improved for forearm fistulae compared with upper arm fistulae. Higher pressures are required to treat stenoses in AVFs compared to AVGs. Outcomes are worse in more severe stenoses, increased patient age, previous interventions and fistulae that develop early stenoses. Major complication rates following angioplasty in dialysis access are between 3 and 5%. Repeat treatments and the use of adjuncts such as drug-coated balloons and stents can prolong the patency of dialysis access. Level of Evidence No level of evidence (Review paper).

Atypical use of PICC as centrally inserted central catheter in infants and neonates: Report of a 10-year experience.

PURPOSE: The aim was to determine the success, safety and post procedure complications of peripherally inserted central catheters as centrally inserted central catheters (CICC). MATERIALS AND METHOD: One hundred and sixty-one consecutive infants and neonates, who underwent image guided tunnelled central venous catheter insertion were retrospectively evaluated between April 2008 and April 2018. Patient's demographics, site of access and procedure details were recorded. Outcomes included technical success and post procedure complications. RESULTS: One hundred and eighty-two CICCs were inserted in 161 patients (49.7%, n = 80 male). Mean patient age was 100 days (range: 0-342) with a mean weight of 4.20 kg (range 1.80-9.40). The most common indication was for antibiotics administration (41%; n = 66). Technical success was 99% (181/182). Early complications (<7 days) were seen in 8.8% (n = 13). This included inadvertent line removal in 5.5%, catheter-related bloodstream infection in 1.1% and catheter occlusion in 2.2% (n = 4). Average line functional duration prior to removal was 26 days (range 0-180). 77.5% of the lines lasted for the intended duration of treatment. In the neonate subgroup, 84.1% (37/44 lines) of lines remained in situ for the intended duration of treatment. CONCLUSION: Tunnelled central venous catheters using non-cuffed peripherally inserted central catheters in infants is a safe technique with excellent success rate and minimal complications rates.

Endovascular salvage of thrombosed haemodialysis vascular access.

Background: Haemodialysis access thrombosis is associated with significant morbidity and access abandonment rates, for which endovascular salvage is a well described treatment option. This study aimed to evaluate the outcomes of endovascular salvage procedures of thrombosed vascular access circuits and identify factors influencing outcomes. Patients and methods: Retrospective review of 328 consecutive procedures performed over 10 years at our institution between January 2010 and December 2019. Patient demographics, access circuit characteristics, procedure details and outcome data were collected. Kaplan-Meier survival curves were used to estimate patency rates and Cox multivariate regression analysis to identify factors affecting outcomes. Results: Technical and clinical success rates were 87.8% and 75.9% respectively. The primary, primary assisted and secondary patency rates at 6 months were 42.2%, 46.7% and 59.1%; and at 12 months were 23.4%, 28.3% and 41.8% respectively. Median access circuit survival was 9.2 months. Major complication rate was 5.2% including 3 procedure-related deaths. Native AVF, lower time from thrombosis to intervention and pharmacomechanical thrombectomy using AngioJetTM predicted positive outcomes. Previous thrombectomy within 3 months and residual thrombus at completion were associated with poorer outcomes. Age and hypertension predicted higher complication rates. Conclusions: This is one of the largest single center series of endovascular salvage of thrombosed haemodialysis access and demonstrates that endovascular treatment is effective and provides durable access circuit survival. Careful patient screening is essential to optimize outcomes.

Utilizing 3D printing to facilitate surgical in-situ paediatric renal artery aneurysm repair for refractory hypertension.

Renal artery aneurysmal (RAA) disease is a rare, but potentially life-threatening cause of renovascular disease presenting with hypertension. Conventional management involves aneurysmal excision followed by renal auto-transplantation. We present the management of a 13-year-old girl with complex multiple saccular aneurysmal disease of the left renal artery with hilar extension and symptomatic hypertension. We used 3D printing to print a patient-specific model that was not implanted in the patient but was used for surgical planning and discussion with the patient and their family. Endovascular options were precluded due to anatomical complexities. Following multi-disciplinary review and patient-specific 3D printing, she underwent successful in-situ RAA repair with intraoperative cooling, without the need for auto-transplantation. 3D printing enabled appreciation of aneurysmal spatial configuration and dimensions that also helped plan the interposition graft length needed following aneurysmal excision. The models provided informed multidisciplinary communications and proved valuable during the consent process with the family for this high-risk procedure. To our knowledge, this is the first reported case utilizing 3D printing to facilitate in-situ complex repair of RAA with intra-hilar extension for paediatric renovascular disease.

Performance of Open and Closed Cell Laser Cut Nitinol Stents for the Treatment of Chronic Iliofemoral Venous Outflow Obstruction in Patients Treated at a Single Centre.

OBJECTIVE: A number of dedicated self expanding nitinol stents have been developed for use in the venous system, with both open cell (OC) and closed cell (CC) designs available. Data comparing these different designs are lacking. The objective of this study was to evaluate outcomes in patients treated with open and closed cells for unilateral chronic iliac vein obstruction. METHODS: A single centre retrospective cohort study was conducted, including all patients treated with a dedicated nitinol venous stent between 2014 and 2019. Stent patency and details of re-interventions (including lysis, venoplasty, reinforcement, extension, arteriovenous fistula formation) were examined in the first post-operative year. Subgroup analysis described outcomes for patients treated with OC and CC stents ending above the inguinal ligament and those who required extension into the common femoral vein. Cox regression analysis was used to identify factors associated with loss of primary patency. RESULTS: A total of 207 patients were included (OC 100 patients, CC 107 patients). There was no significant difference between the groups for age (OC 42 years, CC 44 years); gender (OC and CC 67% female); presence of post-thrombotic lesions (OC 71%, CC 73%); stenting across the inguinal ligament (OC 58%, CC 56%), or presence of inflow disease (OC 49%, CC 47%). Primary and cumulative patency at 12 months were similar between groups (primary: OC 63%, CC 65%; cumulative: OC 93%, CC 90%). Patients with a CC stent across the inguinal ligament had a greater risk of needing multiple re-interventions at one year compared with those with an OC stent (odds ratio 2.84, 95% confidence interval [CI] 1.16 - 6.9) but overall, the only factor significantly associated with loss of primary patency was inflow vessel disease (hazard ratio 3.39, 95% CI 1.73 - 6.62, p < .001). CONCLUSION: OC and CC dedicated nitinol venous stents were observed to perform similarly in terms of patency and symptom improvement at one year. Disease of the inflow vessels was the most important factor associated with a loss of stent patency irrespective of stent design.

Medium-term outcomes after inferior vena cava reconstruction for acute and chronic deep vein thrombosis and retroperitoneal fibrosis.

OBJECTIVE: In the present study, we evaluated the technical and clinical outcomes after endovascular inferior vena cava (IVC) reconstruction in patients with nonmalignant obstruction. METHODS: The preoperative, procedural, and follow-up medical records and imaging studies were retrospectively reviewed for 59 consecutive patients who had undergone endovascular IVC reconstruction for nonmalignant obstruction from February 2014 to January 2019. The patients were classified into three groups according to the quality of their infrainguinal inflow vessels. The outcomes measured were the primary, primary-assisted, and secondary patency rates, reintervention rates, and symptomatic resolution. RESULTS: The indications for treatment were post-thrombotic syndrome (n = 41), acute deep vein thrombosis (n = 12), and retroperitoneal fibrosis (n = 6). The median patient age was 37 years, 11 months, 71.2% were men, and 32.2% had a diagnosis of thrombophilia, with no significant difference in these demographics between the three inflow groups. The median follow-up duration was 2 years, 3 months (range, 6 months to 6 years, 5 months). The whole-cohort primary patency was 91.2%, 71.0%, and 24.1% at 1, 3, and 5 years, respectively. Secondary patency was 76.7% at 1 year and 66.4% at both 3 and 5 years. Inflow group A (no post-thrombotic disease in the femoral or deep femoral veins) demonstrated significantly higher primary patency compared with group B (stenotic disease in one or two infrainguinal inflow veins; P = .009) and significantly higher secondary patency than for both groups B (P = .008) and C (all three infrainguinal inflow veins had stenosed or femoral and/or deep femoral vein occlusion was present; P = .04). In post-thrombotic syndrome patients, the Villalta scores had decreased from a mean of 14.2 to 8.1 at 1 year and 6.8 at 2 years, and the Venous Insufficiency Epidemiological and Economic Study Quality of Life score had improved from a mean of 19.8 to 54.1 and 57.3 at 1 and 2 years, respectively. In the patients with acute deep vein thrombosis, the Villalta score was 2.8 at 1 year and 0 at 2 years. In the patients with retroperitoneal fibrosis, the Venous Insufficiency Epidemiological and Economic Study Quality of Life score had improved from a mean of 25.3 at baseline to 44 at 6 months. CONCLUSIONS: Endovascular IVC reconstruction for nonmalignant obstruction can achieve good patency and clinical improvement, although the outcomes were poorer for patients with post-thrombotic disease of the femoral and deep femoral veins.

Optimising access and provision of interventional radiology service to patients by utilising a new referral system.

OBJECTIVE: Implementing a streamlined interventional radiology (IR) service in the UK has been a challenge. This study aims to review a set of changes introduced in IR at a tertiary centre, including a new referral process and the designation of IR clinical nurse specialists. METHODS: A new process of referring patients to IR using a single generic referral pathway was implemented, replacing an order dropdown-based system. A qualitative survey was designed and distributed as a single-use web link in order to assess the satisfaction and impact of this new process. Responses were based on Likert scale and pertained to perceived qualities of the new referral process. Data analysis was performed to identify specialty and grade-specific trends and possible differences amongst groups. RESULTS: Findings from 98 respondents revealed a strong overall satisfaction with the new referral method and support for its continuation. Subgroup analysis by specialty, concluded medical specialties rated the new referral system more favourably than surgical specialties across all aspects: time efficiency, ease of use, periprocedural support and overall user experience. The new system also increased departmental productivity with an increase in the number of patients treated by 11.2%. CONCLUSION: Micropolicy changes within individual IR departments such as the replacement of a request-based referral system to one which puts IR in control of vetting and patient flow is one of many changes that reinforce the transformational phase of this specialty. ADVANCES IN KNOWLEDGE: Micropolicy changes within IR departments are key in the progression and widespread recognition of the specialty.

Middle aortic syndrome in children and adolescents.

Middle aortic syndrome is a rare form of renovascular disease that may present with severe hypertension during childhood. Narrowing of the abdominal aorta is often associated with narrowing of the renal and/or other visceral arteries and may be secondary to specific genetic syndromes. Following the optimization of blood pressure control, significant aortic narrowing often requires invasive management, including endovascular and surgical intervention. In younger children, endovascular therapy may be attempted in the first instance to acutely reduce the pressure gradient across the narrowing; however, a sustained benefit is rare. Once the child has grown to accommodate a graft of an adequate size, surgical therapy is indicated for patients in whom medical and/or endovascular management has not resulted in adequate blood pressure control. It is critical that individuals with middle aortic syndrome be managed by an experienced multidisciplinary team that includes medical, endovascular, and surgical expertise that can provide long-term care to monitor for recurrent hypertension and evidence of end-organ damage.

Percutaneous Venous Reconstruction for Central Thrombosis-Associated Chylothorax: A Safe and Efficacious Option.

Central thrombosis-associated chylothorax is underrecognized in children and frequently refractory to conservative management. Central venous catheterizations are the predominate cause. We present 3 cases highlighting endovascular techniques used to treat persistent chylous effusions. (Level of Difficulty: Advanced.).

One Year Outcomes of the VIVO-EU Study of Treatment of Symptomatic Iliofemoral Outflow Obstruction with the Zilver Vena Venous Self-Expanding Stent.

OBJECTIVE: To evaluate the performance of the Zilver® Vena™ Venous Stent in the treatment of patients with symptomatic iliofemoral outflow obstruction. METHODS: Between August 2012 and January 2015, 35 patients (mean age of 45.1 ± 15.5 years; 77.1% female) with symptomatic iliofemoral venous outflow obstruction were treated with the Zilver Vena Venous Stent (Cook Ireland, Ltd.) as part of this prospective, single arm, multicenter study. Study assessments included procedural success, major adverse events (MAEs), freedom from occlusion and qualitative patency at 6 and 12 month post-procedure, clinical symptoms of venous insufficiency, and reintervention with the treated venous segment. RESULTS: The rate of freedom from occlusion at 6 month and 12 month was 88.2%. The rate of qualitative patency was 88.2% at 6 month and 85.2% at 12 month. Three MAEs were reported: one symptomatic pulmonary embolism and two clinically-driven reinterventions. Following stenting, clinical symptoms of venous insufficiency improved significantly from baseline at each follow-up, as measured by VDS (p < 0.0001), CEAP "C" (p ≤ 0.0001), VCSS (p < 0.0001), and CIVIQ (p < 0.0001). CONCLUSION: Clinical results with the Zilver Vena Venous Stent were favorable through 12 month, with high patency rates, reduction of venous insufficiency symptoms, and low morbidity.

A multicenter randomized controlled trial indicates that paclitaxel-coated balloons provide no benefit for arteriovenous fistulas.

The role of paclitaxel-coated balloons has been established in the coronary and peripheral arterial circulations with recent interest in the use of paclitaxel-coated balloons to improve patency rates following angioplasty of arteriovenous fistulas. To assess the efficacy of paclitaxel-coated angioplasty balloons to prolong the survival time of target lesion primary patency in arteriovenous fistulas, we designed an investigator-led multi-center randomized controlled trial with follow up time variable for a minimum of one year. Patients with an arteriovenous fistula who were undergoing an angioplasty for a clinical indication were included but patients with one or more lesions outside the treatment segment were excluded. Following successful treatment with a high-pressure balloon, 212 patients were randomized. In the intervention arm, the second component was insertion of a paclitaxel-coated balloon. In the control arm, an identical procedure was followed, but using a standard balloon. The primary endpoint was time to loss of clinically driven target lesion primary patency. Primary analysis showed no significant evidence for a difference in time to end of target lesion primary patency between groups: hazard ratio 1.18 with a 95% confidence interval of 0.78 to 1.79. There were no significant differences for any secondary outcomes, including patency outcomes and adverse events. Thus, our study demonstrated no evidence that paclitaxel-coated balloons provide benefit, following standard care high-pressure balloon angioplasty, in the treatment of arteriovenous fistulas. Hence, in view of the benefit suggested by other trials, the role of paclitaxel-coated angioplasty balloons remains uncertain.

Transcatheter Embolization of the Inferior Epigastric Artery: Technique and Clinical Outcomes.

PURPOSE: Symptomatic rectus muscle sheath hematoma may be the result of bleeding originating from the inferior epigastric artery. We report the technique and the results from a series of consecutive patients treated by transcatheter embolization, evaluating both ipsilateral and contralateral retrograde approaches. METHODS: This was a retrospective study including patients with verified rectus muscle sheath hematoma as a result of active extravasation from the inferior epigastric artery referred for transcatheter embolization. Technical success, clinical success and major complications were calculated. In addition, minor complications, blood transfusions required after a technically successful embolization, length of stay, peri-procedural and 30-day mortality and overall survival at 6 months were obtained. All statistical analysis was performed using SPSS. RESULTS: Twenty-one patients (mean age = 59.67 ± 19.51 years old) were included. The cause of the bleeding in the vast majority was iatrogenic trauma (n = 12/21, 57.14%). Both contralateral (n = 12/21, 57.14%%) and ipsilateral (n = 9/21, 42.86%) retrograde approaches were used. Embolic materials included micro-coils (n = 13/20, 65%), microspheres (PVA) (n = 1/20, 5%), a combination of PVA and micro-coils (n = 5/20, 25%) and gel-foam (n = 1/20, 5%). Overall technical success was 95.2% (n = 20/21) while clinical success was achieved in all but one of the technically successful cases 95% (n = 19/20). One patient died peri-procedurally due to profound hemodynamic shock. There were no other major complications. Additional transfusion was necessary in 7 patients (n = 7/21, 33.33%). There was a significant increase in the hemoglobin levels after the embolization (7.03 ± 1.78 g/dL pre-procedure Vs 10.91 ± 1.7 g/dL post-procedure, p = 0.048). The median hospital stay was 8 days. The peri-procedure and 30-day mortality was 4.8% (n = 1/21) and 28.6% (n = 6/21) respectively. The 6-month survival was 61.9% (13/21). CONCLUSION: Percutaneous embolization of the inferior epigastric artery is a minimally invasive method with satisfactory results. Both ipsilateral and contralateral retrograde approaches are feasible.

Silent and dangerous: catheter-associated right atrial thrombus (CRAT) in children on chronic haemodialysis.

BACKGROUND: Catheter-associated right atrial thrombus (CRAT) is a recognised complication of central venous catheter (CVC) use for haemodialysis (HD) patients. METHODS: This was a single-centre retrospective longitudinal observational study of consecutive children aged 6 months-18 years over a 7-year period receiving in-centre chronic HD. Echocardiograms as per routine cardiac surveillance were performed 6 months or earlier given clinical concerns. RESULTS: Sixty-five children, 36 boys (55.4%), median (IQR) age 11.8 (5.3, 14.7) years, received HD for kidney failure with replacement therapy (KFRT). Initial modality was HD in 45 (69.2%), with CVC as initial access in 42 (93.3%) and AVF in 3 (6.7%); in the remaining 20 (30.8%) patients PD was the initial modality before switching to HD. Seven of 65 (10.8%) developed CRAT at median 2 (0.8, 8.4) months from CVC insertion, with one CRAT detected 3 days following insertion. One child had 2 episodes of CRAT and one additionally thrombosed their AVF. No patient had an underlying primary kidney disease associated with a pro-thrombotic state. Those with CRAT were younger, had more frequent CVC change and received dialysis for longer duration compared to those with no CRAT. Six episodes of CRAT (75%) received anticoagulation therapy. Infective complications were observed in 25% and catheter malfunction in 50%. Five CRAT episodes (62.5%) resulted in CVC loss. One patient died after a haemorrhagic complication of anticoagulation and sepsis, and another developed life-threatening superior vena cava obstruction syndrome. Overall mortality 14% (1/7). CONCLUSIONS: This is the first report of CRAT in a paediatric HD population. There was ~ 11% incidence of CRAT in patients receiving chronic HD detected by surveillance echocardiography. Although frequently asymptomatic, CRAT is associated with serious sequelae. Anticoagulation and surveillance with expert echocardiography remain mainstays of management. Graphical abstract.

Sclerotherapy treatment of a large venous malformation invading the bladder wall related to Klippel-Trenaunay syndrome.

We report the case of a 35-year-old woman who presented with recurrent macroscopic haematuria and known diagnosis of Klippel-Trenaunay syndrome. Imaging and cystoscopy identified an extensive venous malformation involving a large area of the bladder wall. Holmium laser therapy was ineffective at obtaining symptom control. Following a multidisciplinary team meeting, transvenous sclerotherapy with sodium tetradecyl sulphate was performed under image guidance. A reduction in venous density was observed on cystoscopy and the patient has had complete resolution of symptoms within 6 weeks and continued to be asymptomatic up to 24-month follow-up. We propose that transvenous sclerotherapy is considered first-line treatment in this clinical setting.

Catheter-directed thrombolysis to treat acute pulmonary thrombosis in a patient with COVID-19 pneumonia.

We describe a case of a patient who presented to the emergency department with severe shortness of breath and was diagnosed with mild COVID-19 pneumonia and concomitant intermediate-high risk saddle pulmonary thromboembolism. Additionally, the patient had sustained a significant head injury 2 days prior due to a syncopal episode. The patient was treated successfully with catheter-directed thrombolysis (CDT). The case highlights the importance of considering thromboembolic complications in COVID-19 infection, independent of the severity of the associated pneumonia. The case also demonstrates the potential benefit of CDT in treating COVID-19-related thromboembolism.

AngioJet Pharmacomechanical Thrombectomy and Catheter Directed Thrombolysis vs. Catheter Directed Thrombolysis Alone for the Treatment of Iliofemoral Deep Vein Thrombosis: A Single Centre Retrospective Cohort Study.

OBJECTIVE: Percutaneous thrombus removal is used for the treatment of iliofemoral deep vein thrombosis (DVT), but the efficacy of different treatment modalities has not yet been determined. The aim of this study was to compare the outcomes of patients treated with additional AngioJet pharmacomechanical thrombectomy (PCDT) vs. catheter directed lysis (CDT) alone. METHODS: A retrospective review of all patients who received thrombolysis for the treatment of symptomatic acute iliofemoral DVT between 2011 and 2017 was carried out. Outcome measures included the incidence of post-thrombotic syndrome (PTS), procedural outcomes (lytic exposure), the incidence of complications, and vessel patency. All patients were followed up for a minimum of one year. RESULTS: A total of 151 limbs were treated, 70 limbs with PCDT and 81 limbs with CDT alone. Demographic data and prevalence of risk factors were comparable. Incidence of PTS (Villalta score at one year) showed no significant difference (22.2% PCDT vs. 24.7% CDT alone, p = .74). Use of PCDT resulted in a non-statistically significant trend for fewer bleeds (n = 4/63 [6.3%] vs. 13/76 [17.1%]; relative risk 0.37, 95% confidence interval [CI] 0.13-1.08; p = .07), a statistically significant reduction in lysis duration (40 h [95% CI 34-46] vs. 53 h [95% CI 49-58]; p < .001) and a reduction in lytic dose (49 mg [95% CI 42-55] vs. 57 mg [95% CI 52-61]; p = .011) compared with CDT. This reduction was accentuated in 24 cases primarily treated with AngioJet PowerPulse mode (27 h, 95% CI 20-34 [p < .001] and 42 mg, 95% CI 34-50 [p = .009]). Incidences of complications were comparable between groups, with one death due to an intracranial haemorrhage following CDT. Although the incidence of haemoglobinuria was increased following PCDT (12/63 [19.0%] vs. 3/76 [3.9%]; p = .006), no significant difference in acute kidney injury was observed (3/63 [4.8%] vs. 1/76 [1.3%]; p = .33). No significant difference in vessel patency over two years was observed (p = .73). CONCLUSION: The use of PCDT for the treatment of iliofemoral DVT was observed to provide comparable patient outcomes, comparable vessel patency, an acceptable safety profile, and reduced overall lytic dose.