Myocardial perfusion positron emission tomography (PET) has long been regarded as a gold standard of myocardial blood flow (MBF) measurement. However, since randomized clinical trials showed the prognostic value of fractional flow reserve (FFR)-guided revascularization, FFR has rapidly become a new gold standard of functionally significant coronary artery disease (CAD). Despite the predominance of FFR in the management of stable CAD, FFR also has limitations. Overcoming hurdles by the lesion-specific MBF measurement by hybrid imaging and novel flow parameter can be a complimentary tool.