A Bright Future for Laser Atherectomy?

(Leipzig, Germany) January 29, 2020 -- First-time data on ‘Advancing laser therapy: Different settings for different lesions’ was presented on Tuesday morning by George Adams, MD (University of North Carolina Medical Center, Raleigh, NC), who walked through the potential of laser atherectomy in complex femoropopliteal lesions.

Dr Adams stressed that laser atherectomy – which utilizes minimally invasive high-energy pulses to unblock arteries – is one of the only modalities to increase luminal area in all plaque morphologies (homogeneous, heterogeneous, calcific, and restenotic).

“In addition to increasing luminal area, the vessel is prepped such that recoil and dissections are minimized when adjunctive balloon angioplasty is performed,” he said. “With the advent of biological therapies to prevent restenosis, laser atherectomy may also help in the delivery of these biologics to the media and adventitia of the vessel.”

In terms of the existing data on laser atherectomy, the EXCITE ISR study¹ showed that laser atherectomy is beneficial in in-stent restenosis, with 73.5% freedom from target lesion revascularization (TLR) at six months, noted Dr Adams. What’s more, the CELLO registry showed that there was a greater than 40% acute reduction in diameter stenosis when using laser atherectomy in femoropopliteal lesions.²

In terms of its benefit when using biologic therapy, Dr Adams added: “When using laser atherectomy with drug-coated balloons (DCB) in ISR superficial femoral artery lesions, there was an 87.1% freedom from TLR at 12 months in Tosaka III ISR [in-stent restenosis].”

Dr Adams also touched upon personalized laser atherectomy; in other words, tuning laser settings to combat individual plaque morphology. “Different laser settings (low – 40 fluence/60 Hz, medium – 60 fluence/40 Hz, high – 60 fluence/60 Hz) affect luminal gain differently,” he said. “Understanding this concept helps develop a personalized algorithm to treat patients with different plaque morphologies.

“This algorithm will help improve patient outcomes by understanding which patients do best/worst with differing laser settings – optimizing the setting used and the number of passes needed. Additionally, personalized algorithms have the potential to streamline the procedure, optimizing time in the lab, and resulting in improved fiscal responsibility.”

Framing the first-time data from his experience for the LINC audience, Dr Adams shared some of the key outcomes: “Freedom in TLR at 6 months was high (89.5%) using laser atherectomy,” he said. “In all lesions (homogeneous, heterogeneous, calcific, and restenotic), a significant reduction in diameter stenosis was demonstrated post laser treatment. Specifically, heterogeneous and restenotic lesions demonstrated the greatest increase in mean luminal area after laser therapy.

“Of the 6 patients who restenosed at 6 months – 50% were calcific and 50% were restenotic. This restenotic group was older with longer lesion lengths and they all had hypertension, high cholesterol, and a history of CAD [coronary artery disease]. Interestingly, none of the patients with restenosis at 6 months had diabetes.”

He added, “The only group that derived a benefit in using all three laser settings (low/medium/high) to increase mean luminal area was the heterogeneous group. The other three could remove the low and/or medium setting.”

Framing his take-home message, Dr Adams stressed that the “original concept” of gaining the largest possible lumen with atherectomy may only be part of the story. “From our data, the largest lumen was obtained in the heterogeneous group, which also had the largest TLR at 6 months (although granted, it was a small cohort). The concept of prepping the vessel may be more plausible.”

References

1. Dippel EJ, Makam P, Kovach R, et al. Randomized controlled study of excimer laser atherectomy for treatment of femoropopliteal in-stent restenosis: initial results from the EXCITE ISR trial (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis). JACC Cardiovasc Interv. 2015;8(1 Pt A):92-101.
2. Dave RM, Patlola R, Kollmeyer K, et al. Excimer laser recanalization of femoropopliteal lesions and 1-year patency: results of the CELLO registry. J Endovasc Ther. 2009;16(6):665-675. doi:10.1583/09-2781.1