Data from the PROMISE II study detail the effects of transcatheter arterialization procedures with the LimFlow System for reducing the rate of amputation in people with chronic limb-threatening ischemia.
For patients with chronic limb-threatening ischemia, use of an advanced arterialization technique could result in increased likelihood of keeping the limb in question, according to the results of a recent study.
Named the PROMISE II trial, results of the study, which examined the effects of transcatheter arterialization, indicate limb salvage was attained in 76% of patients when using the technique and just more than two-thirds of patients had amputation-free survival at 6 months.
“This procedure is the only option for a subset of patients with severe vascular disease who are at risk for amputation of their limbs,” said coprincipal investigator Daniel Clair, MD, professor and chair, Department of Vascular Surgery at the Vanderbilt University Medical Center.2 “Patients with long-standing diabetes and severe vascular disease in the foot itself often have no way to restore enough blood flow to the foot to heal wounds. In the past, a majority of these patients ended up losing their limbs.”
A prospective, single-group, multicenter trial launched with the intent of evaluating the safety and efficacy of transcatheter arterialization, the PROMISE II study was launched in 2019 and enrolled a population of 105 patients with chronic limb-threatening ischemia. For inclusion in the study, patients were required to have non healing ulcers and no surgical or endovascular revascularization treatment options.1
Overall 219 patients underwent screening as part of the study. Among the 105 enrolled in the suited, the median age was 70 (interquartile range [IQR], 38-89) years, 31.4% were women, and 42.8% were Black, Hispanic, or Latino. Investigators pointed out 68 patients were classified as Rutherford class 5 and 37 were classified as class 6.1
The LimFlow System was used to perform the transcatheter arterialization procedures. Investigators pointed out all study physicians who performed the procedure received didactic and hands-on training.1
The primary endpoint of interest was a composite of amputation-free survival at 6 months. For the purpose of analysis, amputation-free survival was defined as freedom from above-ankle amputation or death from any cause. Investigators pointed out the performance goal for the trial was set at 54%. Secondary outcomes of interest included limb salvage, wound healing, and technical success of the procedure.1
Upon analysis, results indicated transcatheter arterialization of the deep veins was performed successfully in 99.0% of the 105 patients who underwent enrollment. At 6 months, 66.1% of the cohort had amputation-free survival and, according to Bayesian analysis, the posterior probability that amputation-free survival at 6 months exceeded a performance goal of 54% was 0.993, which exceeded the prespecified threshold of 0.977.1
Further analysis of secondary endpoints revealed limb salvage was attained in 76% of patients and wounds were completely healed in 25% of patients. Investigators also highlighted 51% of wounds were in the process of healing and there were no unanticipated device-related adverse events reported in the trial.1
“These patients are literally called ‘no-option’ patients. No option means no hope,” said lead investigator Mehdi Shishehbor, DO, MPH, PhD, president of University Hospitals Harrington Heart & Vascular Institute, and Angela and James Hambrick Chair in Innovation.3 “With this study, we are providing hope for a safe and effective alternative to amputation and a better life for thousands of patients. Once approved by the FDA, we look forward to this procedure being widely available to patients who so desperately need it.”