As Transcatheter Cardiovascular Therapeutics (TCT) 2023 has come to a close, it is time to review some of the most impactful studies that were shared at the conference. In the peripheral artery disease (PAD) space, results of the LIFE-BTK (pivotaL Investigation of saFety and Efficacy of BRS Treatment-Below The Knee) study showed promise for a drug-eluting resorbable scaffold in the treatment of below-the-knee (BTK) chronic limb-threatening ischemia (CLTI). Additionally, an updated patient-level meta-analysis of paclitaxel-coated device use in femoropopliteal PAD was presented, with findings confirming no association between the use of paclitaxel-coated devices and risk of mortality. In the pulmonary embolism (PE) space, the results of the REAL-PE (Real World Experience of Contemporary Pulmonary Embolism Treatment [USCDT versus MT]) study demonstrated significant differences in bleeding rates between patients treated with mechanical thrombectomy and ultrasound-assisted catheter-directed thrombolysis (US-CDT). Further, the STRIKE-PE (Study of the Long-Term Safety and Outcomes of Treating Pulmonary Embolism With the Indigo Aspiration System) investigators shared an interim analysis of 90-day outcomes for patients treated with computer-assisted vacuum thrombectomy. Each of these studies will be addressed in more depth in this expert analysis.

LIFE-BTK Study

The LIFE-BTK study, presented by Ramon L. Varcoe, MB, BS, PhD, MMed (Clin Epi), on behalf of the LIFE-BTK investigators and simultaneously published in the New England Journal of Medicine, described the use of the Esprit everolimus-coated resorbable scaffold (Abbott Laboratories, Abbott Park, Illinois) for the treatment of BTK CLTI.¹ In this multicenter randomized controlled trial (RCT), 261 patients with BTK CLTI were randomized in a 2:1 ratio to receive treatment with the everolimus-eluting resorbable scaffold or angioplasty. At 1 year, the primary efficacy endpoint of freedom from major amputation, target-vessel occlusion, target-lesion binary restenosis, and clinically driven target-lesion revascularization was observed in 74% of patients treated with the Esprit resorbable scaffold as opposed to 44% of patients treated with angioplasty, meeting significance for superiority with a 30% absolute difference between treatment groups and a number needed to treat of four. The primary safety endpoint of freedom from major adverse limb events at 6 months and perioperative death within 30 days was also noninferior for the resorbable scaffold. After >20 years of stagnant results, this landmark trial represents a breakthrough in the treatment of patients with BTK CLTI and will likely serve as a blueprint for future trials in the space.

Patient-Level Meta-Analysis of Paclitaxel Safety in Femoropopliteal PAD Treatment

After 5 years of controversy regarding the safety of paclitaxel-coated balloons following the 2018 study-level meta-analysis by Katsanos et al., William A. Gray, MD, FACC, FSCAI, shared the results of an updated patient-level meta-analysis simultaneously published in The Lancet that investigated the safety of paclitaxel-coated balloons for the treatment of femoropopliteal PAD.^2,3 This meta-analysis used data from 2,666 patients included in the RCTs comparing Food and Drug Administration (FDA)–approved paclitaxel-coated devices against noncoated devices. In intention-to-treat, as-treated, and crossover-adjusted analyses with up to 5-year follow-up, no association was observed between the usage or dosage of paclitaxel-coated devices and an increased risk of mortality. These results were shared with the FDA earlier this year, leading to a reversal of the previous restrictions placed on the use of paclitaxel-coated devices.⁴

REAL-PE Study

The REAL-PE study, presented by Peter Monteleone, MD, and simultaneously published in the Journal of the Society for Cardiovascular Angiography & Interventions, described outcomes for patients with PE following mechanical thrombectomy and US-CDT.⁵ In this real-world analysis of 2,259 patients, 1,577 of whom were treated with US-CDT and 682 of whom were treated with mechanical thrombectomy, the incidence of major bleeding according to several different bleeding metrics was shown to be significantly higher for patients treated with mechanical thrombectomy as opposed to US-CDT. In the primary regression analyses, patients treated with mechanical thrombectomy were 1.37 times more likely to experience International Society on Thrombosis and Haemostasis (ISTH)–defined major hemorrhage and 1.23 times more likely to experience Bleeding Academic Research Consortium (BARC) grade 3b bleeding events. In addition, rates of intracranial hemorrhage were significantly higher in patients treated with mechanical thrombectomy. The results of this big-data analysis corroborate what has been described on a single-institution level by Feroz et al.⁶

STRIKE-PE: 90-Day Interim Results

In a moderated abstract session, Suhail Dohad, MD, FACC, RVT, shared interim safety, performance, and quality of life (QoL) results following treatment of PE with computer-assisted thrombectomy.⁷ In the 150 patients already enrolled in the STRIKE-PE and treated with the Indigo^® Aspiration System (Penumbra Inc., Alameda, California), the right ventricular/left ventricular ratio was shown to improve from 1.39 at baseline to 1.01 at 48 hours post procedure, with a major adverse event rate of 2.7% within this 48-hour window. Importantly, at 90 days, patients treated with the aspiration system experienced significant improvements in all domains of general QoL as measured by the five-level EQ-5D (EQ-5D-5L), as well as all but one domain of disease-specific QoL as measured by the Pulmonary Embolism Quality of Life (PEmb-QoL).

References

1. Varcoe RL, DeRubertis BG, Kolluri R, et al.; LIFE-BTK Investigators. Drug-eluting resorbable scaffold versus angioplasty for infrapopliteal artery disease. N Engl J Med 2023;Oct 25:[ePub ahead of print].
2. Parikh SA, Schneider PA, Mullin CM, Rogers T, Gray WA. Mortality in randomised controlled trials using paclitaxel-coated devices for femoropopliteal interventional procedures: an updated patient-level meta-analysis. Lancet 2023;Oct 23:[ePub ahead of print].
3. Katsanos K, Spiliopoulos S, Kitrou P, Krokidis M, Karnabatidis D. Risk of death following application of paclitaxel-coated balloons and stents in the femoropopliteal artery of the leg: a systematic review and meta-analysis of randomized controlled trials. J Am Heart Assoc 2018;Dec 18:[ePub ahead of print].
4. U.S. Food and Drug Administration. UPDATE: Paclitaxel-Coated Devices to Treat Peripheral Arterial Disease Unlikely to Increase Risk of Mortality - Letter to Health Care Providers (FDA website). 2023. Available at: https://www.fda.gov/medical-devices/letters-health-care-providers/update-paclitaxel-coated-devices-treat-peripheral-arterial-disease-unlikely-increase-risk-mortality. Accessed 11/14/2023.
5. Monteleone P, Ahern R, Banerjee S, et al. Modern treatment of pulmonary embolism (USCDT versus MT): results from a real-world, big data analysis (REAL-PE). J Soc Cardiovasc Angiogr Interv 2023;Oct 24:[ePub ahead of print].
6. Feroze R, Arora S, Tashtish N, et al. Comparison of large-bore thrombectomy with catheter-directed thrombolysis for the treatment of pulmonary embolism. J Soc Cardiovasc Angiogr Interv 2023;Jan 3:[ePub ahead of print].
7. Dohad S, Moriarty J, Tamaddon H, et al. TCT-399 STRIKE-PE 90-day interim results: safety, performance, and quality-of-life outcomes in pulmonary embolism patients treated with computer-aided thrombectomy. J Am Coll Cardiol 2023;82:B159–B160.