Unprotected left main coronary artery (ULMCA) disease is seen in 4% of patients 
who undergo angiography. Though coronary artery bypass graft surgery has 
traditionally been the preferred approach to revascularization, recent major 
society guidelines support the use of percutaneous coronary intervention (PCI) 
in properly selected patients. This article provides an overview of recent 
studies evaluating the efficacy of ULMCA PCI and looking at contemporary 
approaches to the evaluation and percutaneous treatment of ULMCA disease. The 
ongoing EXCEL trial will help elucidate the role of ULMCA PCI in the treatment 
of left main disease compared with coronary artery bypass graft surgery.