Impact of Myocardial Bridges on Long-Term Outcomes After Left Anterior Descending Chronic Total Occlusion Recanalization

BACKGROUND A myocardial bridge (MB) is frequently observed after recanalization of a left anterior descending coronary artery (LAD) chronic total occlusion (CTO); however, the long-term prognostic impact of MBs in this specific setting remains controversial. OBJECTIVES The aim of this study was to determine the impact of MBs on long-term outcomes in patients undergoing percutaneous coronary intervention of LAD CTOs. METHODS Consecutive patients with LAD CTOs who underwent intravascular ultrasound-guided percutaneous coronary intervention from January 2019 to December 2021 were retrospectively analyzed. The primary endpoint was the 5-year rate of major adverse cardiac events (MACE), a composite of cardiac death, spontaneous myocardial infarction, and ischemia-driven revascularization. RESULTS Among 685 patients analyzed, MBs were identified in 393 (57.4%) on intravascular ultrasound; stent extension into the bridged segment occurred in 44.3% of these cases (174 of 393). After a median 5-year follow-up, patients with MBs had a higher incidence of MACE compared with those without MBs (16.1% vs 8.9%; P = 0.006), driven primarily by more ischemia-driven revascularization in the MB group (15.1% vs 7.9%; P = 0.004). Stent extension into the MB was associated with a higher rate of MACE compared with sparing the MB (21.4% vs 11.9%; P = 0.0017). MACE rates did not differ between patients with MBs spared from stenting and those without MBs (11.9% vs 8.9%; P = 0.25). CONCLUSIONS MBs are prevalent after LAD CTO recanalization. Although their presence is associated with adverse outcomes, the risk is driven mainly by stent extension into the bridged segment.