More Evidence of Comparable Outcomes for Stenting, Surgery in Chronic Limb Ischemia

Among a varied population of patients with critical limb ischemia (CLI), bypass surgery and endovascular therapy result in similar rates of major amputation and survival at 1 year, according to analysis from a large, multicenter registry.

“The results of this study showed that despite the well-established outcomes of bypass surgery, endovascular therapy remains the leading first-line treatment strategy in CLI patients, said lead author Theodosios Bisdas, MD, PhD (St. Franziskus Hospital, Muenster, Germany), in an email.

He added that future trials should focus less on comparing the strategies against each other and more on specific CLI cohorts likely to benefit from one or the other. “For instance, the risk factor analysis of the registry revealed that such an analysis would be meaningful in patients with chronic kidney disease or in frail patients. At present, none of the ongoing randomized controlled trials is powered enough to provide data on specific cohorts of patients,” Bisdas commented.

Encouraging Results With Both Therapies

To provide a snapshot of current practice in CLI intervention, the researchers conducted an interim analysis of the CRITISCH registry, which included data on 1,200 patients treated at 27 centers in Germany between January 2013 and September 2014.

In their paper published in the December 26, 2016, issue of JACC: Cardiovascular Interventions, Bisdas and colleagues report that more than 50% of patients in the registry received endovascular therapy (balloon angioplasty alone, bare-metal stent, drug-coated balloon, drug-eluting stent, or other device).

“Despite the fact that few data as to the effectiveness of drug-coated balloons in the [superficial femoral artery (SFA)] in CLI patients existed at the time of recruitment, 18% of the patients in our study received DCB therapy in the SFA,” the study authors write. Angioplasty alone and bare-metal stenting were the most common choices, with low rates of DES use seen.

To TCTMD, Bisdas observed that the In.Pact Global study showed excellent patency rates after DCB therapy in more complex lesions, although nearly half of patients in that trial required bailout stenting after treatment of long lesions. “Thus, we would expect that the outcomes might be even better in the endovascular group in our registry if a DCB therapy has been applied prior to stenting of the femoropopliteal lesions,” he said.

Compared with patients who received surgery, those undergoing endovascular therapy in the CRITISCH registry were older and at higher risk overall and were also much more likely to have mild or moderate lesions (TASC A or B) but poorer runoff status.

Those treated with endovascular therapy had much shorter hospital stays than those treated with surgery (7 days vs 15 days; P < 0.001) and had rates of in-hospital mortality that were marginally lower (1% vs 3%; P = 0.085). On multivariable analysis, endovascular therapy was noninferior to bypass surgery (P = 0.003) at 1 year. There were no differences between groups for the secondary endpoints of survival and freedom from major amputation or any reintervention.

Bisdas and colleagues say the real-world registry results suggest “that when physicians are free to individualize therapy for their CLI patients, they achieved encouraging outcomes with both therapies.”

High-Quality Evidence Still Lacking

But in an accompanying editorial, Michael R. Jaff, DO (Newton-Wellesley Hospital, Boston, MA), and Ido Weinberg, MD (Massachusetts General Hospital, Boston, MA), note that it is difficult to draw firm conclusions from the registry data because of “missing information that is imperative when deciding how to treat a particular patient.” That information includes lesion-specific characteristics such as length, presence of calcification, and length of chronic total occlusions, as well as medical therapy and medication use at follow up.

“We totally agree that lesion-specific characteristics would be of great importance,” Bisdas told TCTMD. “However, our main aim was not to analyze specifically the type of endovascular treatment applied in regard to the lesion, but [rather] to have an overview of the first-line treatment strategies and how they performed in real-world scenarios. Thus, we classified the lesion only according to the TASC II classification, which, despite its drawbacks, still remains the most widely used classification system for decision-making among vascular specialists.” He added that his group is planning to evaluate the performance of novel endovascular modalities in CLI patients and to perform a lesion-specific analysis in hopes of shedding more light on the selection criteria of treating physicians, including the clinical, technical and economic aspects of their choices.

In the meantime, Jaff and Weinberg say the field is “still desperate for more high-quality evidence to emerge to aid clinicians on the frontlines make sound, evidence-based decisions regarding CLI management.” Those data may come from the National Institutes of Health’s ongoing, multicenter BEST-CLI trial, which is randomizing CLI patients to endovascular therapy or open surgery. The only other randomized trial, BASIL, showed both strategies to be comparable, but favored surgery for those with a life expectancy of more than 2 years. However, BASIL was published over 10 years ago, and used only balloon angioplasty as the endovascular treatment option, which “prevents meaningful conclusions relevant to modern practice in which many technologies are being evaluated for the endovascular management of CLI,” Jaff and Weinberg say.

Until more relevant data emerge, they conclude that physicians “must rely on a team-based, experience-driven approach by seasoned vascular specialists such as those reporting the CRITISCH registry.”