Clues to Discordance and Dissimilarity Between Coronary Stenosis and Lesion-Specific Ischemia

Abstract

Traditional diagnostic accuracy statistics have defined discordance between a stenosis and preserved coronary blood flow as a false-positive finding. With expanded use of invasive and noninvasive fractional flow reserve (FFR), as well as positron emission tomography measures of coronary flow reserve, our knowledge base has grown substantially, providing greater insight into the underlying rationale for discordant findings. We now understand that the presence of an obstructive stenosis is but one parameter which may elicit reductions in blood flow and prompt ischemic symptoms. Vessel size, collateral flow, and the length of the diseased segment are a few of the factors influencing coronary blood flow.1 Thus, for any given patient with an obstructive stenosis, reductions in coronary blood flow may or may not be present. Throughout the prior reported series,2,3 limited evidence is available with regards to coronary stenosis severity and location, as well as clinical patient subgroups, where the disconnect between stenosis severity and lesion-specific ischemia with FFR may …