Relative coronary flow velocity reserve improves correlation with stress myocardial perfusion imaging in assessment of coronary artery stenoses.
OBJECTIVE
To evaluate the angiographic and coronary flow velocity parameters that best correlate with the results of stress myocardial perfusion imaging.


METHODS
Criterion standard.


METHODS
Tertiary care center.


METHODS
Forty-eight patients undergoing diagnostic coronary angiography for angina or silent ischemia.


METHODS
We performed angiographic and coronary flow velocity measurements at rest and during hyperemia at the post-stenotic segment and in the adjacent angiographically normal branch of the left coronary artery. Relative coronary flow velocity reserve (RCFVR) was calculated as the ratio of post-stenotic to reference vessel coronary flow velocity reserve (CFVR). The best cutoff points for reversible perfusion defects were calculated using receiver operating characteristic curves.


RESULTS
Post-stenotic CFVR showed fairly good correlations with minimal lumen diameter and percentage of diameter stenosis (r = 0.57 and r = 0.55, respectively; p < 0.001). RCFVR showed stronger correlations with these angiographic indexes of stenosis severity (r = 0.66 and r = 0.68, respectively; p < 0.0001). Based on receiver operating characteristic cutoff values (1.67 for post-stenotic CFVR and 0.64 for RCFVR), RCFVR had better agreement with myocardial perfusion imaging results, compared to post-stenotic CFVR (92% vs 75%, respectively). This agreement was more meaningful in patients with moderate coronary artery stenoses (50 to 75%). The area under the curve was 0.65 (not significant) for post-stenotic CFVR and 0.88 (p < 0.01) for RCFVR.


CONCLUSIONS
RCFVR describes better than post-stenotic CFVR the functional significance of coronary artery stenoses.
Voudris
Vassilis
V
First Cardiology Department, Onassis Cardiac Surgery Center, Athens, Greece. vvoudris@otenet.gr
Avramides
Dimitrios
D
Koutelou
Maria
M
Malakos
John
J
Manginas
Athanasios
A
Papadakis
Manolis
M
Cokkinos
Dennis V
DV
D001783:Blood Flow Velocity; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index