Left main stem atherosclerotic disease which supplies the vast portion of the left ventricle myocardium is associated with significant morbidity and mortality. Coronary artery bypass surgery has been the definitive treatment choice. However, advancements in percutaneous coronary intervention (such as drug-eluting stents and techniques, risk stratification, and intravascular ultrasound) have increased the viability of this treatment option.

Left Main Treatment Advances

The fundamental balance between coronary artery bypass surgery and PCI, is the tradeoff of risk of need for revascularization and embolic stroke. Intravascular ultrasound and technique have allow the more precise placement of stents and lower the incidence of acute complications. The development of DES stents and second generation antiplatelet medications and reduced the incidence of in stent restenosis. Surgical advancements reduced the risk of stroke including the expanding use of off-pump CAB, better vein graft patency, and widespread use of LIMA. This pace of development makes the external applicability of trials difficult to interpret.

Guidelines on Left Main Treatment

Both the American and European societal guidelines have endorsed PCI in patients with less-complex coronary disease while CABG still maintains a class I recommendation across all groups. The data to firmly establish the role of percutaneous treatment are currently lacking and the two on-going EXCEL and NOBLE trials will hopefully take us a step further in clarifying the role of PCI in the treatment of LMS disease.

Key References on Left Main Disease Treatment