Use of the Limited Antegrade Subintimal Tracking Technique in Chronic Total Occlusion Percutaneous Coronary Intervention

Background: There are limited data on the limited antegrade subintimal tracking (LAST) technique for chronic total occlusion (CTO) percutaneous coronary intervention (PCI). Objectives: The aim of this study was to analyze the frequency of use and outcomes of the LAST technique for CTO PCI. Methods: We analyzed 2,177 CTO PCIs performed using antegrade dissection and re-entry (ADR) in the PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) registry between 2012 and January 2022 at 39 centers. ADR was attempted in 1,465 cases (67.3%). Results: Among antegrade re-entry cases, LAST was used in 163 (11.1%) (primary LAST in 127 [8.7%] and secondary LAST [LAST after other ADR approaches failed] in 36 [2.5%]), the Stingray system (Boston Scientific) in 980 (66.9%), subintimal tracking and re-entry in 387 (26.4%), and contrast-guided subintimal tracking and re-entry in 29 (2.0%). The mean patient age was 65.2 ± 10 years, and 85.8% were men. There was no significant difference in technical (71.8% vs 77.8%; P = 0.080) and procedural (69.9% vs 75.3%; P = 0.127) success and major cardiac adverse events (1.84% vs 3.53%; P = 0.254) between LAST and non-LAST cases. However, on multivariable analysis, the use of LAST was associated with lower procedural success (OR: 0.61; 95% CI: 0.41-0.91). Primary LAST was associated with higher technical (76.4% vs 55.6%; P = 0.014) and procedural (75.6% vs 50.0%; P = 0.003) success and similar major adverse cardiac event (1.57% vs 2.78%; P = 0.636) rates compared with secondary LAST. Conclusions: LAST was used in 11.1% of antegrade re-entry CTO PCI cases and was associated with lower procedural success on multivariable analysis, suggesting a limited role of LAST in contemporary CTO PCI.