Presence and Relevance of Myocardial Bridge in LAD-PCI of CTO and Non-CTO Lesions

JACC Cardiovasc Interv. 2024 Feb 26;17(4):491-501. doi: 10.1016/j.jcin.2023.12.017. Epub 2024 Feb 7.

Abstract

Background: Intravascular ultrasound (IVUS) studies show that one-quarter of left anterior descending (LAD) arteries have a myocardial bridge. An MB may be associated with stent failure when the stent extends into the MB.

Objectives: The aim of this study was to investigate: 1) the association between an MB and chronic total occlusion (CTO) in any LAD lesions; and 2) the association between an MB and subsequent clinical outcomes after percutaneous coronary intervention in LAD CTOs.

Methods: A total of 3,342 LAD lesions with IVUS-guided percutaneous coronary intervention (280 CTO and 3,062 non-CTO lesions) were included. The primary outcome was target lesion failure (cardiac death, target vessel myocardial infarction, definite stent thrombosis, and ischemic-driven target lesion revascularization).

Results: An MB by IVUS was significantly more prevalent in LAD CTOs than LAD non-CTOs (40.4% [113/280] vs 25.8% [789/3,062]; P < 0.0001). The discrepancy in CTO length between angiography and IVUS was greater in 113 LAD CTOs with an MB than 167 LAD CTOs without an MB (6.0 [Q1, Q3: 0.1, 12.2] mm vs 0.2 [Q1, Q3: -1.4, 8.4] mm; P < 0.0001). Overall, 48.7% (55/113) of LAD CTOs had a stent that extended into an MB after which target lesion failure was significantly higher compared to a stent that did not extend into an MB (26.3% vs 0%; P = 0.0004) or compared to an LAD CTO without an MB (26.3% vs 9.6%; P = 0.02).

Conclusions: An MB was more common in LAD CTO than non-CTO LAD lesions. If present, approximately one-half of LAD CTOs had a stent extending into an MB that, in turn, was associated with worse outcomes.

Keywords: chronic total occlusion; left anterior descending artery; myocardial bridge; percutaneous coronary intervention.

MeSH terms

  • Chronic Disease
  • Coronary Angiography
  • Coronary Occlusion* / diagnostic imaging
  • Coronary Occlusion* / therapy
  • Humans
  • Myocardial Infarction*
  • Percutaneous Coronary Intervention* / adverse effects
  • Treatment Outcome