Guidelines, lighthouses, and a toe in the water.

Aguideline tells you how to get someplace, whereas a lighthouse keeps you off the rocks; both can shepherd you on a safe journey toward your goal. The American College of Cardiology (ACC), in concert with the American Heart Association (AHA), has been at the forefront of developing guidelines for percutaneous coronary interventions (PCI).1 In an era in which there are multiple data sets to draw from, guidelines help to sort out optimal from less optimal evidence-based approaches. Application of these guidelines makes intuitive sense as we counsel our individual patients about the risk/benefit ratio of PCI and as we develop treatment strategies for healthcare delivery systems to employ.