FROM THE COVER: EDUCATE, EDUCATE, AND EDUCATE AGAIN: THE CONTINUING QUEST FOR APPROPRIATE VENOUS CARE

EDUCATION ACROSS THE VENOUS CARE delivery spectrum lies at the heart of efforts to ensure operator judgement is optimal and procedures—like the placement of venous stents—are carried out in the appropriate circumstances.

Or, as Steve Elias, MD, director of the Center for Vein Disease at Englewood Health Network in Englewood, New Jersey, says, “the trend is going to be perhaps that too many stents are going to be placed for a while until we educate people about when this is appropriate, and when it’s not appropriate.”

Elias was speaking ahead of the 2023 American Venous Forum (AVF) where some of the latest data on venous stent usage trends between 2014 and 2021 are to be presented by Karem Harth, MD, director of the Center for Comprehensive Venous Care at UH Harrington Heart & Vascular Institute in Cleveland.

Four dedicated venous stents have been cleared in the U.S.—the Abre, Venovo, Zilver Vena, and Vici devices—with stent migration and overstenting still recurring themes as new research is presented, and surgeons discuss outcomes. Recently, new data from the clinical trial of the Abre dedicated venous stent saw investigator Stephen Black, MD, from Guy’s and St Thomas’ Hospital in London, England—who led the study with Erin Murphy, MD, from Sanger Heart & Vascular Institute, Atrium Health, in Charlotte, North Carolina—declare that, given the study showed no stent fractures through three years, and similarly, no delayed stent migrations, “… stent migration really does seem to be an operator issue rather than a stent issue.”

Elias underscores the point: 99.9% of the time the issue is not one of the stent but of the judgment of the operator, or poor training—“or an issue of considering venous stents are similar to arterial stents,” he tells Vascular Specialist. He emphasizes the role of device makers in education. “Those of us on the leading edge of this are working with all of industry to set up programs to better educate their salesforces, and then also their physician customers, regarding not just stents but also venous disease in general,” he says. “We all realize this is a problem, and the only way to solve it is by all of us working together.”

Data: From IDEs to RCTs

Over the past decade, venous stenting has evolved from a “byword” into a “mainstream and accepted” practice, Black tells Vascular Specialist. In recent times, the on-label, venous-specific devices were made available, along with the first prospective data in the form of investigational device exemption (IDE) trials, and, according to Black, there is now “more enthusiasm for treating patients” among providers in the venous space.

At this juncture, Kush Desai, MD, from Northwestern

University in Chicago, believes the time to embark on “real-world” studies is now, with the aim of “demonstrating the value of treatment of patients across a variety of disease states, from non-thrombotic through post-thrombotic.” He explains that these data will help physicians to “clearly identify which patients benefit and what we can expect for outcomes.”

Black concurs, adding that randomized controlled trials (RCTs) will need to follow, despite the difficulties associated with carrying out such research. The “big problem” here is recruitment—a problem that is affecting various ongoing trials. This recruitment issue is multifactorial, Black notes, specifying that clinicians “feel they do not have equipoise anymore,” and among some there is a “financial conflict bias,” while patients “do not want not to be treated.” The solution? According to Black, clinicians need to work as a group to “overcome our own biases,” in order to ensure randomized evidence ensues.

Desai also points to the importance of data consolidation, referencing in particular the work of the Deep Venous Academic Research Consortium, which he chairs alongside Black. “The goal of this is to improve the rigour and reproducibility of deep venous research,” Desai explains, by way of ensuring that studies are all collecting the same trial data, so that they can be compared. He hopes that this creates “more sound data” for the devices that practitioners are placing, and will thus have a “downstream effect” on impacting clinical practice.

Rabih Chaer, MD, chief of the division of vascular surgery at the University of Pittsburgh in Pennsylvania, notes that “longer-term” data might still be lacking for the individual stents, as well as comparative data between the different stents, that are available for venous placement.

“That becomes important because, at least, the newer-generation venous dedicated stents have shown us that some have performed better in certain locations based on the design of the stent,” he says. “There may be some variability in the performance of each stent, depending on which part of the vein, and for which indication that they are used.”

In parallel to the need for more data, Desai posits there is “quite a long way to go” in terms of refining venous stenting practice. “The devices are very good,” he says, noting that, while there is “certainly room for improvement,” outcomes across studies are “very similar—sort of agnostic to the stent device”.

Both Black and Desai highlight the importance of understanding the specifics of venous disease when it comes to best practice. “Part of the problem with venous is people move very freely from being able to do arterial intervention and suddenly assume they can do a venous intervention,” Black remarks. “It is like playing squash and tennis,” he analogizes. “They are both racket sports continued from page 1 with a ball, but the rules are not the same.”

According to Desai, the “biggest issues” in terms of practice are with patient selection and disease state recognition. “Simply put, there are far too many stents placed for non-thrombotic disease in the U.S., meaning there is attribution of symptoms that are not likely to significantly improve with placement of a stent.” He states that this can be attributed in part by economic benefits to the operators—which he says “may be a uniquely U.S. thing”—however notes that there are “likely a variety of problems at play.”

Black stresses that “inappropriateness of care” is the key issue, and that one of the main challenges facing venous stenting practice is ensuring “the right patient get the right treatment by people trained who know how to do it properly.”

Non-thrombotic iliac vein lesions (NIVLs) are at particular risk of overtreatment, he says, because “the impetus is to treat anybody with any leg problem on the left-hand side” when there are lots of patients who do not need treatment. In the case of chronic occlusions and post-thrombotic disease, and potentially acute iliofemoral deep vein thrombosis (DVT), he notes there are lots of patients who are not getting treatment who would “probably benefit.”

Education and training

Considering how venous stenting practice can be improved, Desai believes education is key. “I think most providers would be open to the discussion that ‘maybe your stent is not helping patients,’ and would correct their behavior,” he says, while remarking that it is “much more difficult to correct” the practice of providers who are financially driven. “More broadly speaking,” however, he is confident that education remains central “for providers that are willing to listen.” Black points out that a number of educational efforts are in place—from company-run symposia and training to workshops at vascular meetings. He stresses however that training is a “two-way thing.” He explains: “You have to engage in training.”

Looking at the wider picture, Black highlights that, while vascular care “continues to suffer from an unreasonable focus on aortic disease,” there is a “huge opportunity in the treatment of venous disease to make a really big difference to a patient’s quality of life.”

With this in mind, he encourages “all vascular enthusiasts” to commit to collecting the data, partaking in the training, and delivering the appropriate care that should be the hallmarks of venous stenting’s next chapter. Chaer says the venous stenting space has come a long way but looks forward to further improvements to come—“in terms of more data as it pertains to the existing stents, and maybe looking at the hybrid designs, so to speak, to see how these will perform.”

Registry analysis finds women benefit from endovenous ablation with fewer complications

Varicose Veins

AN EVALUATION OF THE VASCULAR QUALITY Initiative’s (VQI) Varicose Vein Registry (VVR) carried out by the Midwestern Vascular Surgical Society (MVSS) found women to benefit similarly from endovenous ablation as men, but that they experience fewer complications post-procedure (writes Eva Malpass)

The MVSS study prospectively collected data from the VVR—a registry included within the Society for Vascular Surgery’s VQI. Uniquely, the VVR includes both patient-and physician-reported outcomes.

Using these data, Benjamin A. Y. Cher, MD, from the University of Michigan, and colleagues conducted a retrospective cohort evaluation of patients undergoing endovenous ablation procedures on truncal veins with or without treatment of perforated veins between 2015 and 2019.

Cher and colleagues summarized that their findings demonstrate a similar benefit from endovenous ablation between women and men, with little incidence of post-procedural complications for both. However, considering the study’s procedural registry included almost twice as many women as men, findings which suggest a greater benefit from treatment for women are particularly significant.

The findings were published in the Journal of Vascular Surgery: Venous and Lymphatic Disorders (JVS-VL), November edition

Venous Ulcers

Surgical Therapy

A single-center evaluation of contemporary, multi-modal surgical therapy for venous stasis ulceration (C6 disease) suggests highrisk patients showed similar healing rates at one year, indicating a variety of intervention types should be pursued to achieve “optimal results,” writes Eva Malpass.

PRESENTED AT THE SOUTHERN Association for Vascular Surgery (SAVS) annual meeting (Jan. 18–21), Rachel Reed, MD, a general surgery resident at Emory University in Atlanta, outlined the “significant burden” chronic venous disease (CVD) places on both patients and the U.S. healthcare system.

Reed and colleagues conducted a retrospective review of patients treated with C6 disease at a single, public academic hospital between 2011–2021, with at least 12-months follow-up. She noted that there are currently “limited data” regarding combined surgical therapy in venous disease, introducing their study as the “only” one performed looking at multiple types of surgical intervention.

Their primary outcome measure was defined as ulcer-free survival at one year following initial surgical intervention, which included venous ablation, deep venous stenting, and open deep venous valvuloplasty.

Patients were classified using the Clinical, Etiological, Anatomical, and Pathophys iological (CEAP) system, which categorizes C6 disease as its most severe form of venous disease, assessed by a multidisciplinary team.

Reed addressed several comorbidities characterizing the “high-risk” cohort, such as “diabetes, elevated body mass index [BMI] and active insurance”—specifying that 60% of the included population were classified as obese with a BMI greater than 30, and 35% had a prior history of deep vein thrombosis (DVT).

Producing the results, Reed identified the 80 interventional procedures included in their review, segmenting these into 70% ablation, the most frequent treatment used; 21.3% stenting; and 10% deep venous reconstruction (DVR). Their findings showed 54% of patients were ulcer-free at 12-month follow-up, but no significant demographic disparities were found between patients who healed and those who did not.

“Of note, those with high-risk features, including diabetes and elevated BMI, healed at a similar rate to those without,” Reed told SAVS 2023 attendees.

Overall, 37.7% of patients required more than one type of procedure; 71.7% underwent isolated venous ablation; 13.2% received isolated iliac vein stenting; and 1.8% were treated with isolated valvu- loplasty. Elucidating the data further still, she emphasized a prevalent “trend” that showed that patients who required multiple types of intervention to obtain durable venous healing were more likely to have ulcer resistance at 12 months—most likely “highlighting the severity of their disease,” Reed determined.

Yet, despite the number or type of procedure that were performed, no “statistically significant difference” was observed in the level of ulcer healing, Reed stated.

When the researchers segmented healing rates of patient limbs by intervention type, she explained, concomitant iliac vein disease appeared to be “associated with reduced ulcer healing at one year,” suggesting iliac vein stenting is associated with poor ulcer healing compared to those individuals who did not require this procedure.

The research team’s findings suggest that high-risk features such as diabetes and increased BMI are “not predictive” of poor ulcer healing, with patients from both cohorts healing at “similar” rates, Reed and colleagues concluded.

However, when considered after multivariable regression, Reed saw that significant demographics appeared to be “increased age and lack of insurance” as indicators of reduced healing at 12 months. “Chronic venous disease remains a challenging disease to treat and in which to obtain durable venous healing,” Reed contended. “Future studies will need to be performed on optimal treatment pathways for these patients.”

Meta-analysis of post-thrombotic syndrome finds one in five at risk of long-term symptoms following isolated distal DVT

Anew meta-analysis is the first to report the pooled risk of post-thrombotic syndrome (PTS) after isolated distal deep vein thrombosis (DVT). Researchers revealed a onein-five risk of long-term PTS after isolated distal DVT, with one in 50 patients progressing to severe PTS, potentially developing to ulceration.

Principal author Benedict Turner, MBChB, from Imperial College London in London, England, and colleagues evaluated The Cochrane Library, Embase, Google Scholar and MEDLINE databases, following PRISMA guidelines to identify eligible prospective cohort studies analyzing the rate of PTS after a first episode of isolated distal DVT.

Published in the European Journal of Vascular and Endovascular Surgery, the study comprised trials held between 2005 and 2021 that included between 52 and 403 participants, with a total of 1,105 included across all seven studies reporting the development of PTS.

Turner et al note that the baseline characteristics of included articles were varied—follow-up periods ranged between one month to four years after the first DVT, and several studies additionally reported which of the distal deep veins were thrombosed and corresponding risk factors.

Interventions used to treat PTS included stockings, though duration, adherence and degree of compression were heterogenous. Other patients also received anticoag- ulation, although duration of treatment was unspecified. Among patients who were anticoagulated, direct oral anticoagulants, low molecular weight heparin and vitamin K antagonists were used.

The authors report that one in five patients are at risk of long-term PTS after isolated distal DVT, with one in 50 experiencing severe symptoms that may potentially include ulceration.

Going into detail, the authors observed a post-thrombotic rate of 17% ( p<0.01) across the seven studies, 217 cases and 1,105 participants. Three of these studies (302 patients) reported on the severity of PTS symptoms, 78% posited as mild (Villalta score 5–9), 11% as moderate (10–14), and 11% were severe (15 or more).

Even when modulating the follow-up period, the authors did not see a significant change in the risk of developing PTS (p=0.71). This, they write, suggests shorter follow-up periods may be adequate to collect data on symptom development in clinical trials.

The authors note that methods of data collection may have been “confounding” due to recall bias, as most of the included studies only reported rates of PTS at the average follow-up duration, rather than pinpointing the exact time at which PTS was diagnosed.

Overall, Turner and colleagues state that the risk of PTS after isolated distal DVT appears to be half that in comparison to proximal DVT, although occurring in a similar timeframe. According to the authors, this information is key when considering anticoagulation duration and compression therapy, as “PTS is noted to be the principal moderator of quality-of-life after VTE [for patients].”

When considering preventative measures that can be taken by patients, the authors note that the most recent European Society for Vascular Surgery (ESVS) guidance recommends graduated compression stockings in the proximal context of DVT to prevent the onset of PTS, despite the UK National Institute for Health and Care Excellence and American College of Chest Physicians withdrawing this treatment option since it demonstrated no additional benefit in the SOX trial.

The authors highlight that analysis of stocking use is limited. They detail that trials, including CHAPS, SOX and ATTRACT, have set about evaluating the treatment for preventing PTS. However, they each excluded distal DVT from their eligibility criteria due to assumed lower event rates, although it may constitute up to two thirds of all DVT cases.

The investigators conclude that randomized trials to analyze and support interventions that can effectively prevent PTS are “urgently needed” to improve patient care and subsequent outcomes after isolated distal DVT.—Eva Malpass