Assessing the left main stem in the cardiac catheterization laboratory. What is "significant"? Function, imaging or both?

Area of Science:

• Cardiology
• Interventional Cardiology
• Medical Imaging

Background:

• Significant Left Main Stem (LMS) disease requires revascularization for improved clinical outcomes.
• Conventional angiography (≥50% luminal stenosis) has limitations in defining functional significance of LMS stenosis.
• Percutaneous coronary intervention and Coronary Artery Bypass Grafting are revascularization options for LMS disease.

Purpose of the Study:

• To highlight common pitfalls and misconceptions in assessing LMS stenoses.
• To propose an algorithm for guiding revascularization decisions in LMS disease.
• To emphasize the role of adjunctive technologies in LMS disease assessment.

Main Methods:

• Review of current literature on LMS stenosis assessment.
• Discussion of limitations of conventional angiography.
• Integration of Intravascular Ultrasound (IVUS) and Fractional Flow Reserve (FFR) in assessment.

Main Results:

• Angiography alone is often insufficient for accurate LMS stenosis assessment.
• Adjunctive technologies like IVUS and FFR provide superior anatomical and physiological evaluation.
• Improved assessment leads to better procedural and clinical outcomes.

Conclusions:

• Accurate assessment of LMS stenosis is critical for appropriate revascularization.
• Adjunctive imaging and physiological assessment improve decision-making for LMS disease.
• A structured approach and algorithm can aid in managing LMS disease.