Choosing a Method for Guiding PCI

In contemporary clinical practice, interventional cardiologists use both fractional flow reserve (FFR) and intravascular ultrasonography (IVUS) to guide percutaneous coronary intervention (PCI) for intermediate coronary stenosis (i.e., a narrowing of the coronary-artery lumen by 40 to 70%). FFR, a physiological test, is used to evaluate the ischemic potential of a stenosis and decide whether PCI is needed. IVUS, a high-resolution intracoronary imaging method, is used to select the appropriate stent size and to determine whether the stent is correctly placed and sized after implantation. These tools are necessary because the severity of a stenosis on a coronary angiogram does not . . .