More data necessary to positively affect CLI management

SAN DIEGO — Randomized controlled trials and systematic data are necessary to impact how to treat patients with critical limb ischemia, in addition to learning more about how to reduce costs and positively change practice patterns, according to a presentation at TCT 2018.

There is currently a global peripheral artery disease epidemic, and according to a study published in Vascular Medicine in 2008, the Medicare expenditure on CLI at the time was more than $4 billion. More recent estimates on Medicare expenditures are closer to $20 billion, Matthew T. Menard, MD, assistant professor of surgery at Brigham and Women’s Hospital, said during the presentation.

Around the 1960s, endovascular therapy became a major treatment option for patients with lower-extremity disease. Since then, it has been adopted as a first strategy by interventionalists and vascular surgeons, but medical therapy may displace it before long, Menard said.

“We’re all at risk for losing our jobs or being put out of business by medical therapy,” Menard said. “The COMPASS trial was certainly encouraging. ... If trends continue, there’s going to be some medical therapy done down the road.”

In the CRITISCH registry from Germany published in the Journal of Vascular Surgery in 2015, vascular surgery was performed frequently in patients with CLI, with initial revascularization efforts consisting of about 45% bypass, comparable with the 40% bypass figure shown in recent Vascular Quality Initiative data, he said.

“This actually matches my experience going around the country for the BEST-CLI trial,” Menard said. “There is still a lot of vascular surgery being done.”

The BEST-CLI trial is currently trying to determine which first revascularization option on CLI has the best value: bypass surgery or endovascular therapy. A study published in The New England Journal of Medicine in 1991 addressed the issue of value between the two methods.

“[The researchers] didn’t get very far, and I’m positive that we haven’t moved the bar very far forward in 30 years since,” Menard said.

The most internally valid forms of evidence result from randomized controlled trials, as a well-designed trial identifies the optimal course of action in research settings, Menard said.

There are 16 high-impact CV guidelines to power health care decisions by providers, payers and consumers, which consist of 2,711 recommendations, and only 11% were based upon enough evidence to warrant the recommendation, Menard said. The majority of the recommendations were based upon expert opinion and a single trial.

In a study published in the American Heart Journal in 2014, researchers found that there is a lack of high-quality data that can guide decision-making.

“The limits of the current data are rampant, but probably the biggest culprit are the endpoints that are used,” Menard said. “Amputation-free survival, target lesion and target vessel revascularization do absolutely an abysmal job of actually targeting the metrics that we really care about.”

More evidence is needed, especially since effective health interventions are often very expensive, according to the presentation. This has formed the backdrop of the BEST-CLI trial, which was designed to assess the cost and value of vascular surgery and endovascular therapy. The novel primary endpoint of this trial is major adverse limb event-free survival, defined as above-the-ankle amputation or major reintervention. Secondary endpoints include freedom from hemodynamic failure, freedom from CLI, freedom from clinical failure, number of reinterventions per limb salvaged and freedom from reinterventions in index limb.

“Endpoints such as this, hopefully, will give us a far better metric of exactly what’s going on,” Menard said.

Optimal medical therapy is another benefit that will be assessed in the BEST-CLI trial.

“We’re going to get a true benchmark and a true report card in terms of how we’re all doing in terms of hypertension control, diabetes and statin use,” Menard said. – by Darlene Dobkowski

References:

Menard MT. Critical Limb Ischemia Deep Dive. Presented at: TCT Scientific Symposium; Sept. 21-25, 2018; San Diego.

Bisdas T, et al. J Vasc Surg. 2015;doi:10.1016/j.jvs.2015.04.441.

Hirsch AT, et al. Vasc Med. 2008;doi:10.1177/1358863X08089277.

Jones WS, et al. Am Heart J. 2014;doi:10.1016/j.ahj.2013.12.012.

Tunis SR, et al. N Engl J Med. 1991;doi:10.1056/NEJM199108223250806.

Disclosure: Menard reports he is a co-chair for the BEST-CLI trial and is on the scientific advisory board for Aralez and Janssen.