Comparison of synchrotron radiation angiography with conventional angiography for the diagnosis of in-stent restenosis after percutaneous transluminal coronary angioplasty.
OBJECTIVE
Synchrotron radiation angiography (SRA) is a novel tool for minimally invasive coronary artery imaging. The method uses subtraction of two images produced at energies bracketing the iodine K-edge after intravenous infusion of iodinated contrast agent. We investigated the accuracy of SRA for detecting in-stent restenosis (ISR).


RESULTS
We recruited 57 men, 4-6 months after successful PTCA. We visualized the right coronary artery (RCA) in 27 patients with 36 stented segments [12 segments with ISR>50% by quantitative coronary angiography (QCA)], and the left anterior descending artery (LAD) in 30 patients with 37 stented segments (10 ISR). SRA and QCA were performed within 2 days of each other. Two experienced observers unaware of QCA data evaluated the SRA results. Image quality was good or excellent in most patients. Global sensitivity was 64%, specificity was 95%, and positive and negative predictive values were approximately 85%. Inter-observer kappa concordance coefficient was 0.86. False negatives involved short eccentric lesions and superimposed segments, most frequently of the LAD. False positives occurred in intermediate stenoses slightly overestimated by SRA.


CONCLUSIONS
In men, this minimally invasive approach, using small radiation doses, detects significant ISR in the RCA, but the LAD poses difficulties because of superimposition with others structures.
Bertrand
Bernard
B
INSERM-U647/ESRF, Grenoble, France. bbertrand@chu-grenoble.fr
Estève
François
F
Elleaume
Hélène
H
Nemoz
Christian
C
Fiedler
Stefan
S
Bravin
Alberto
A
Berruyer
Gilles
G
Brochard
Thierry
T
Renier
Michel
M
Machecourt
Jacques
J
Thomlinson
William
W
Le Bas
Jean-François
JF
D000328:Adult; D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods; D017023:Coronary Angiography / Q000379:methods*; D023903:Coronary Restenosis / Q000000981:diagnostic imaging*; D023921:Coronary Stenosis / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D015607:Stents; D017356:Synchrotrons / Q000592:standards*