The Challenge of CLI: Endovascular Tibial Interventions Show Promise
Drug-eluting stents, drug-coated balloons and atherectomy are emerging as treatment options for this difficult-to-treat population.
Patients with critical limb ischemia and below-the-knee lesions are notoriously difficult to treat, and the most common tibial endovascular intervention, percutaneous transluminal angioplasty, often does not provide a long-term solution.
Therefore, there is great interest in other endovascular tibial interventions beyond percutaneous transluminal angioplasty (PTA). Certain data on the use of atherectomy and drug-eluting stents have been encouraging, whereas drug-eluting balloons have not yet shown to be effective in this patient population.
Interest in Atherectomy
Different atherectomy devices have successfully treated different kinds of tibial lesions, but operators should not assume one device will work for all patients with CLI, James F. McKinsey, MD, vascular surgeon and vice chairman of the Mount Sinai-Roosevelt Hospital and systems chief of complex aortic intervention for the Mount Sinai Systems, said during a presentation at VIVA 2017 in Las Vegas.
Current evidence indicates that directional atherectomy works best for calcified, intimal hyperplasia and mixed-plaque lesions; photoablation atherectomy works best for thrombotic, intimal hyperplasia and mixed-plaque lesions; rotational atherectomy works best for thrombotic and intimal hyperplasia lesions; and orbital atherectomy works best for calcified lesions, according to McKinsey.
“Atherectomy definitely has a role in the treatment of patients with critical limb ischemia below the knee,” he told the audience.
Interest in DCBs
Another focus in this area is determining whether a DCB or a direct injection that leaves no material behind is a successful treatment option for tibial lesions, according to Lawrence A. Garcia, MD, director of interventional cardiology and co-director of vascular medicine at St. Elizabeth’s Medical Center and associate professor of medicine at Tufts University School of Medicine.
However, initial trial results have not been encouraging, he said at VIVA. The IN.PACT DEEP study of patients with below-the-knee lesions treated with the IN.PACT Amphirion DCB (Medtronic), which is no longer on the market, “was a very negative trial that prompted a lot of scrutiny about how we treat patients with CLI or infrapopliteal disease.”
Treatment of patients with CLI using a variety of drugs with direct injection platforms such as a micro-infusion device (Bullfrog, Mercator MedSystems) is a strategy that has shown encouraging results in early studies. However, pivotal studies have not yet been completed, he said.
“There are no current data to report that a DCB or alternative therapy via injection is superior to angioplasty alone,” Garcia said. “Ongoing trials will hopefully provide improved outcomes for our patients with CLI.”
Interest in DES
Early studies of DES in tibial applications have been encouraging. One meta-analysis, published in CardioVascular and Interventional Radiology in 2013, indicated RR reductions associated with DES of 52% for primary patency, 55% for target lesion revascularization and 40% for limb amputation, Konstantinos Katsanos, MD, PhD, interventional radiologist at Patras University Hospital in Rio, Greece, said during a presentation.
In a network meta-analysis of studies that evaluated below-the-knee treatments, DES “were the only technology that consistently showed significant reduction [in limb amputation] compared with other treatments. It is the only treatment proven so far to achieve a significant reduction in major limb loss,” Katsanos said.
“Tibial drug-eluting stents seem to significantly improve patency, reduce TLR and reduce major amputations compared to plain old angioplasty and bare-metal stents,” Katsanos said. “Absorbable scaffolds may hold some promise in the future, especially in young patients.” - by Erik Swain
- Garcia LA. Tibial Tricks of the Trade. Presented at: VIVA 17; Sept. 11-14, 2017; Las Vegas.
- Katsanos K. Tibial Tricks of the Trade. Presented at: VIVA 17; Sept. 11-14, 2017; Las Vegas.
- Katsanos K, et al. Cardiovasc Intervent Radiol. 2013;doi:10.1007/s00270-013-0578-2.
- Katsanos K, et al. J Endovasc Ther. 2016;doi:10.1177/1526602816671740.
- McKinsey JF. Tibial Tricks of the Trade. Presented at: VIVA 17; Sept. 11-14, 2017; Las Vegas.
- Zeller T, et al. J Am Coll Cardiol. 2014;doi:10.1016/j.jacc.2014.06.1198.
- For more information:
- Lawrence A. Garcia, MD, can be reached at firstname.lastname@example.org.
- Konstantinos Katsanos, MD, PhD, can be reached at email@example.com.
- James F. McKinsey, MD, can be reached at firstname.lastname@example.org.
Disclosures: Garcia reports that he received honoraria from Medtronic; consulted for Boston Scientific and Medtronic; held common stock in Arsenal, CV Ingenuity, Essential Medical, Scion Cardiovascular, Spirox, Syntervention and TissueGen; and received research funding from Abbott Vascular, Boston Scientific and Medtronic. Katsanos reports he received honoraria from Boston Scientific and Medtronic and research funding from Abbott Vascular. McKinsey reports he received honoraria from Abbott Vascular, Bolton Medical, C.R. Bard, Cook Medical, Covidien, CV Ingenuity, Medtronic and Spectranetics; and consulted for Bolton Medical and Spectranetics.
Editor’s Note: This article was updated on Jan. 31, 2018 to correct the name of the DCB used in the IN.PACT DEEP trial. The Editors regret the error.