A systematic review of current trends in pharmacologic management after stent placement in nonthrombotic iliac vein lesions

Objective Stenting of the iliac vein is increasingly recognized as a treatment for chronic venous insufficiency (CVI). However, the pharmacologic management after stent placement is unclear. This review was conducted to illustrate recent trends in anticoagulation and antiplatelet regimens following stent placement for nonthrombotic iliac vein lesions (NIVL). Methods The MEDLINE database was searched using the term “iliac vein stent.” Retrieval of articles was limited to studies conducted on humans and published in English between 2010 and 2020. Studies were included that described iliac vein stent placement. Studies were excluded that contained fewer than 25 patients, performed procedures other than stent placement, did not specify the postoperative anticoagulant used, or treated lesions of thrombotic origin. Results 12 articles were included in this review, yielding a total of 2782 patients with a male-to-female ratio of 0.77. The predominant CEAP classification encountered was C3. The most common stent used in the included studies was the Wallstent (9/12), and the most common pharmacologic regimen was 3 months of clopidogrel (6/12). Warfarin, aspirin, cilostazol, and rivaroxaban were among other agents used. Primary stent patency ranged from 63.1 to 98.3%. There was no apparent correlation between pharmacologic agent used and stent patency or subjective patient outcomes. Conclusion Multiple different approaches are being taken to pharmacologically manage patients following stent placement for NIVL. There is no consensus on which agent is best, nor is there a formal algorithmic approach for making this decision. Additionally, the findings in this study call into question whether anticoagulation following stenting for NIVL is necessary at all, given the similar outcomes among the different agents utilized. This review underscores the potential value of undertaking a multi-institutional prospective study to determine what is the best pharmacologic therapy following venous stent placement for NIVL.

Short – term outcomes of flow diverter stent (Pipeline) for treatment intracranial aneurysms

Background: With the approval of detachable coils in 1995, endovascular treatment of intracranial aneurysms has become an alternative to surgical clip ligation. Despite the introduction of “modified” coils and advanced techniques such as stent-assisted and balloon-assisted coiling, coil embolization has major limitations because of inability to completely and permanently occlude all aneurysms. As stents were being developed for intracranial use, it was hypothesized that stents could be utilized to divert flow “away” from the aneurysm “back” into the parent vessel, and the concept of “endovascular flow diversion” was proposed. This study aims to report our experience with cerebral aneurysms, which may improve in the treatment with the flow-diverter stent and follow up (1). Methods: This study was conducted in consecutive series of 23 patients. 23 procedures were performed for treating these patients in Ha Noi heart hospital from January 2019 to January 2020. 23 flow diverter stents (Pipeline) were used. Aneurysms morphology, stent patency and cerebral parenchyma before and after intervention were analyzed on images of digital subtraction angiography (DSA), computed tomography (CT) and magnetic resonance (MR). The follow-up data after 3–6 months and 12 months were recorded. Results: In 23 patients (8 men, 15 women), aneurysms of internal carotid artery were mostly common (95.7%), especially in cavernous segments. 13 cases (74%) had saccular aneurysms, and 2 cases (9%) had multiple aneurysms, and only 3 cases (13%) had fusiform aneurysms. Endovascular treatment was successfully performed at rate of 100%.. Mortality and morbidity rates were 0% and 0%, respectively. MRI and MSCT follow-up at 3 months showed complete or incomplete occlusions of aneurysms was 26.1% or 34.8%, respectively. Conclusions: Deployment of flow diverter stent is safe and effective with high rate of successful and low procedural complications

Clinical characteristics, laboratory findings and anatomy of intracranial aneurysms in group of patients treated with flow diverter stent (Pipeline)

Background: This study aim to report our experience with cerebral aneurysm, which may improve in the treatment with the flow diverter stent and follow up. Methods: This study was conducted in consecutive series of 23 patients. 23 procedures were performed for treating these patients in Ha Noi heart hospital from January 2019 to January 2020. 23 flow diverter stents (Pipeline) were used. Aneurysm morphology, stent patency and cerebral parenchyma before and after intervention were analyzed on images of digital subtraction angiography (DSA), computed tomography (CT) and magnetic resonance (MR). The follow-up data after 3–6 months and 12 months were recorded. Results: In 23 patients (8 men, 15 women), aneurysms of internal carotid artery were mostly common (95.7%), especially in cavernous segments. 13 cases (74%) had saccular aneurysms, and 2 cases (9%) had multiple aneurysms, and only 3 cases (13%) had fusiform aneurysms. Endovascular treatment was successfully performed at rate of 100%. Mortality and morbidity rates were 0% and 0%, respectively. MRI and MSCT follow-up at 3 months showed complete or incomplete occlusions of aneurysms was 26.1% or 34.8%, respectively. Conclusion: Unruptured intracranial aneurysms are often detected incidentally on screening imaging in high risk patients, such as women, middle age, estrogen deficiency, and hypertension. The aneurysm is usually small in the cavernous segment of the anterior cerebral artery.

Study of endovascular treatment in obstructive aortoiliac lesions: Immediate and short-term results

Objective: Aorto-iliac occlusive disease (AIOD) is a common atherosclerotic disease causing significant morbidity. Transatlantic intersociety consensus for the management of peripheral arterial disease (TASC II) recommends endovascular therapy (ET) for better management of patients with lesions type A and B. With the advent of endovascular therapy, type C and D lesions management is becoming more feasible with endovascular therapy than open surgery for aorto-iliac occlusive disease. We aimed to evaluate patients with AOID and to describe short-term outcome of endovascular treatment for such lesions. Methods: Patients with aorto-iliac occlusive diseases who underwent endovascular therapy were enrolled in the study. Their demographic data and risk factors were recorded. Patients were followed at 3 and 6 months and their primary patency rate and symptom status were recorded. Results: We enrolled 100 patients with a mean age of 59.77 (8.75) years with the majority of patients being male. The most common presentation was claudication (59%) followed by rest pain (31%) and gangrene (20%). The majority of patients had Transatlantic inter-society consensus (TASC) II type A (44%) and type B (31%) lesions; 15% of patients had types C lesions and the remaining 10% patients had type D lesions. Access site hematoma and contrast-induced nephropathy were present in 7% and 5% of patients respectively. Stent patency rate was 97% and 95% at 3 and 6 months follow up respectively. Conclusion: Endovascular therapy in aorto-iliac occlusive disease is a safe, effective, and low-cost treatment option with a high patency rate and symptomatic improvement in the short-term.

A Systematic Review and Meta-Analysis of 12-Month Patency After Intervention for Iliofemoral Obstruction Using Dedicated or Non-Dedicated Venous Stents

Background: Endovascular stenting of the deep venous system has been proposed as a method to treat patients with symptomatic iliofemoral outflow obstruction. The purpose of this systematic review and meta-analysis was to compare the effectiveness of this treatment at 1-year following the development of dedicated venous stents. Method and results: We searched MEDLINE and EMBASE for studies evaluating the effectiveness of venous stent placement. Data were extracted by disease pathogenesis: non-thrombotic iliac vein lesions (NIVL), acute thrombotic (DVT), or post-thrombotic syndrome (PTS). Main outcomes included technical success, stent patency at 1 year and symptom relief. A total of 49 studies reporting outcomes in 5154 patients (NIVL, 1431; DVT, 950; PTS, 2773) were included in the meta-analysis. Technical success rates were comparable among groups (97%-100%). There were no periprocedural deaths. Minor bleeding was reported in up to 5% of patients and major bleeding in 0.5% upon intervention. Transient back pain was noted in 55% of PTS patients following intervention. There was significant heterogeneity between studies reporting outcomes in PTS patients. Primary and cumulative patency at 1 year was: NIVL—96% and 100%; DVT—91% and 97%; PTS (stents above the ligament)—77% and 94%, and; PTS (stents across the ligament)—78% and 94%. There were insufficient data to compare patency outcomes of dedicated and nondedicated venous stents in patients with acute DVT. In NIVL and PTS patients, stent patency was comparable at 1 year. There was inconsistency in the use of validated tools for the measurement of symptoms before and after intervention. When reported, venous claudication, improved in 83% of PTS patients and 90% of NIVL patients, and ulcer healing occurred in 80% of PTS patients and 32% of NIVL patients. Conclusions: The first generation of dedicated venous stents perform comparably in terms of patency and clinical outcomes to non-dedicated technologies at 1 year for the treatment of patients with NIVL and PTS. However, significant heterogeneity exists between studies and standardized criteria are urgently needed to report outcomes in patients undergoing deep venous stenting.

Treatment Failure of Venous Stenting With or Without Direct Oral Anticoagulants (DOAC) / Non-Vitamin K Oral Anticoagulants (NOACs) in Patients With Deep Vein Thrombosis (DVT) in Term of the Stent Patency: Protocol for a Systematic Review

Background: Venous stenting plays a significant role in the treatment of acute deep vein thrombosis (DVT). But the adjuvant anti-coagulant therapy could also help to more successful patency rate. We hope to elucidate the differences in the patency rate of venous stenting with or without direct oral anticoagulants (DOAC) / non-vitamin K oral anticoagulants (NOACs). Methods: Studies that work on the stent patency rate in venous stent with or without DOAC / NOAC will be included. The primary studies (Cohort, case control, case-series or randomized/ non-randomized trials) will be included if the participants / patients have had acute or chronic DVT, with venous stenting (at least one study group or all of study subjects) who have received DOAC / NOAC agents. The stent patency rate should be reported in all of study subjects within a follow-up time, minimum for 1 year. We will perform an electronic search on published or in press articles, which have been published in MEDLINE / PubMed, Embase, the online Cochrane database, CENTRAL and searches of clinical trial registries: clinicalTrials.gov, EU Clinical Trials, ISRCTN registry, WHO network registry for trials. PROSPERO databases will be manually searched for protocols.After screening of the relevant articles, selection and data extraction will be conducted in duplicate and independently. Methodological quality of the selected studies will be assessed using the Newcastle Ottawa Scale (NOS) tool. We will use “Hazard Ratio” (HR) as the optimum Effect Size (ES) in this meta-analysis, otherwise we will use or calculate “Risk Ratio” (RR) or “Odds Ratio” (OR) ES measures as the selected study specific ES. Discussion: In this review, we hope to find the treatment failure/ success rate of venous stenting with or without DOAC / NOAC regards to the stent patency rate and will try to provide insights into the right choice of anti-coagulant therapy.Submitted to PROSPERO (20/9/2021): CRD42021274542

P.195 Giant aneurysm, tiny patient: flow diversion stenting of a giant MCA aneurysm in a young child

Background: A 3-year-old girl presented with a 6-day history of severe headaches. On examination, upper motor neuron signs were noted in the left upper and lower extremities with increased tone, reflexes, and a positive Babinski sign. MRI of the brain revealed a giant right middle cerebral artery (MCA) aneurysm with significant mass effect, associated with cerebral edema and ventricular effacement. CT and CT angiogram showed evidence of aneurysmal wall calcification and lamellar thrombosis within the aneurysmal sac. In addition, there was a smaller right MCA aneurysm in close proximity to the giant aneurysm. Methods: After a balloon occlusion test to assess collateral blood flow to the MCA territory, it was decided to treat both aneurysms with a flow diverting stent. Dual antiplatelet loading was done with aspirin and clopidogrel. The smallest available diameter of Pipeline Shield stent was deployed. Results: The patient remained neurologically unchanged. Early follow-up imaging demonstrated stent patency, reduced size and mass effect of the large aneurysm, reduced cerebral edema, and no flow into the smaller aneurysm. Conclusions: Flow diversion stenting may be employed successfully in pediatric patients, though has unique technical considerations including small size vessels and limited evidence for antiplatelet agent choice and dosing.

Abstract 1122‐000210: Cangrelor to Prevent Intraluminal Thrombosis in Endovascular Therapy for Acute Stroke: Single Center Case Series

Introduction : Intraluminal thrombosis after endovascular therapy (EVT) is a peri‐procedural complication that carries a high burden of morbidity and mortality. The use of anti‐thrombotic therapies during EVT remains an evolving field. Recent surveys suggest the glycoprotein IIb/IIIa inhibitor, tirofiban, is often used during EVT. However, the increased intracranial hemorrhage risk and the medication’s long half‐life pose significant challenges to management. Cangrelor, an intravenous and reversible P2Y12 inhibitor, was first approved by FDA in 2015 for use in patients with coronary artery disease undergoing percutaneous intervention. Its rapid onset and offset are beneficial as an anti‐thrombotic during EVT. Our case series aim to characterize the safety and efficacy of cangrelor use in our institution and contribute towards its growing body of data. Methods : Chart review was conducted for patients that required endovascular therapy for acute stroke and received intravenous cangrelor at our center between January 2019 to December 2020. We included patients that underwent both extracranial and intracranial stent placement, as well as patients who suffered from intraluminal thromboses intra‐procedurally. Variables of interest included lesion pathophysiology, peri‐procedural complications including intraluminal re‐occlusion and intracranial hemorrhage, TICI score post‐procedurally, vessel patency and MRS on post‐hospitalization followup. Results : Nine patients received intravenous cangrelor during endovascular therapy. Mean age was 50 (range 41–67 years old), 3/9 patients were male. Seven patients (77.8%) had ischemic stroke, of whom five exhibited tandem intracranial occlusions and three required intraprocedural stent deployment. 3/7 patients received IV TPA prior to EVT. Interestingly, one patient had a previously placed Precise stent for acute internal carotid thrombus, briefly placed on eptifibatide (180mcg/kg), suffered from stent re‐occlusion on POD1 and required repeat thrombectomy with cangrelor intra‐procedurally; stent patency was maintained for the rest of her hospital course. One patient received balloon angioplasty of supraclinoid internal carotid artery. The remaining two patients required cangrelor for visualized intraluminal platelet aggregates during the EVT. Two patients presented with aneurysmal subarachnoid hemorrhage, one treated with flow diversion stent and the other requiring stenting for prolapsed aneurysm coiling. Dosing of cangrelor bolus and infusion varied. Six patients were bolused with 15 mcg/kg, while three patients received 7.5 mcg/kg. Infusion rates range from 0.5 to 4 mcg/kg/minute with all nine patients reaching therapeutic range P2Y12 levels on post‐procedural testing. Cangrelor infusion was transitioned to oral antiplatelet on post‐operative day 4 on average. In all nine patients, vessel and stent patency was maintained intra‐procedurally with cangrelor. Subsequent vascular imaging during hospitalization demonstrated no intraluminal thrombosis. One patient experienced intracranial hemorrhage, however they received intraprocedural eptifibatide (180mcg/kg) and cangrelor infusion (15 mcg/kg bolus, 2 mcg/kg/min) for their extensive clot burden and triple stent placement. Five patients attended three‐month post‐hospitalization followups. Their median MRS was 2 and all followup vessel imaging demonstrated patent vessels. Conclusions : Our case series demonstrate the promising efficacy of cangrelor in patients undergoing emergent endovascular therapy to prevent intraluminal thrombosis. Further studies with larger sample sizes can elucidate the optimal dose of cangrelor, length of treatment before oral transition, and compare its efficacy to eptifibatide.