Correlation of poststenotic hyperemic coronary flow velocity and pressure with abnormal stress myocardial perfusion imaging in coronary artery disease.

Abstract The functional significance of coronary stenoses is frequently determined by adjunctive noninvasive myocardial perfusion imaging. Poststenotic coronary flow velocity and pressure can be measured directly during routine cardiac catheterization. The aim of this study was to correlate poststenotic (distal) flow velocity and pressure with stress perfusion imaging in patients. Quantitative angiography, basal and hyperemic transstenotic coronary flow velocities, and pressure gradients were measured in 50 patients within 1 week of exercise (n = 29) or of pharmacologic (n = 21) stress perfusion imaging. Twenty-two of 25 patients (88%) with reversible perfusion abnormalities had diminished distal coronary flow velocity reserves (CFVR) of ≤2.0 × baseline, whereas 22 of 25 (88%) with normal perfusion imaging studies had a normal distal CFVR of > 2.0 (p = 0.0001). Thirteen of 25 patients (52%) with reversible perfusion abnormalities had transstenotic gradients ≥ 20 mm Hg, whereas 20 of 25 (80%) with normal perfusion studies had gradients