Related Experiment Video
Updated: Jul 11, 2026
Myocardial Infarction and Functional Outcome Assessment in Pigs
Published on: April 25, 2014
Presence and Relevance of Myocardial Bridge in LAD-PCI of CTO and Non-CTO Lesions
Kei Yamamoto1, Yoichiro Sugizaki1, Dimitri Karmpaliotis2
1Division of Cardiology, Department of Medicine, Columbia University Medical Center, New York, New York, USA; Clinical Trials Center, Cardiovascular Research Foundation, New York, New York, USA.
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.
Insights
Myocardial bridges (MB) are more common in left anterior descending (LAD) chronic total occlusions (CTOs). Stenting into an MB in LAD CTOs significantly increases the risk of target lesion failure.
Area of Science:
- Cardiology
- Interventional Cardiology
- Vascular Ultrasound
Background:
- Myocardial bridges (MB) are found in approximately 25% of left anterior descending (LAD) arteries.
- Stent failure is a concern when stents are placed within an MB in the LAD artery.
Purpose of the Study:
- To determine the association between MB and LAD chronic total occlusions (CTOs).
- To evaluate the impact of MB on clinical outcomes after percutaneous coronary intervention (PCI) in LAD CTOs.
Main Methods:
- Analysis of 3,342 LAD lesions undergoing IVUS-guided PCI, including 280 CTOs.
- Primary outcome: target lesion failure (cardiac death, MI, stent thrombosis, revascularization).
Main Results:
- MB prevalence was higher in LAD CTOs (40.4%) than non-CTOs (25.8%).
- Discrepancy in CTO length between angiography and IVUS was greater with MB.
- Target lesion failure was significantly higher (26.3%) when stents extended into MB in LAD CTOs compared to those without MB (9.6%).
Conclusions:
- Myocardial bridges are more prevalent in LAD CTOs compared to non-CTOs.
- Approximately half of LAD CTOs with MB had stents extending into the bridge, leading to worse clinical outcomes.
Related Concept Videos
01:24Cardiac Catheterization III: Left Heart Catheterization
01:26Coronary Artery Disease II: Pathophysiology
01:27Coronary Artery Disease V: Interprofessional Care
01:30Acute Coronary Syndrome I: Introduction
01:19Acute Coronary Syndrome II: Pathophysiology and Clinical Manifestations
01:30Acute Coronary Syndrome III: Diagnostic Studies