While coronary angiography assess the extent and the structural severity of fixed coronary stenoses, angiography does not provide functional information regarding<unk>  limitations.  While exercise tolerance testing may provide this functional information, only a quarter to a third of patients undergoing cardiac catheterization may have undergone stress test before cardiac catheterization.  Thus there is the need for diagnostic studies to assess the functional significance of stenoses in the cardiac catheterization laboratory.  While intervention in a critically narrowed lesion is appropriate, a considerable number of lesions are of “intermediate” severity on coronary angiography. Assessment of<unk>  <unk>  may improve the ability to assess the functinal consequences of such lesions in the cardiac catheterization laboratory .
Fractional flow reserve
Coronary flow reserve
Quantitative coronary angiography
Peak flow meter
Pulse wave velocity
TIMI frame count 
Coronary artery calcium scoring
Doppler echocardiography