Reproducibility of intravascular ultrasound radiofrequency data analysis: implications for the design of longitudinal studies.
OBJECTIVE
The purpose of this study was to assess in vivo the reproducibility of tissue characterization using spectral analysis of intravascular ultrasound (IVUS) radiofrequency data (IVUS-VH).


BACKGROUND
Despite the need for reproducibility data to design longitudinal studies, such information remains unexplored.


RESULTS
IVUS-VH (Volcano Corp., Rancho Cordova, USA) was performed in patients referred for elective percutaneous intervention and in whom a non-intervened vessel was judged suitable for a safe IVUS interrogation. The IVUS catheters used were commercially available catheters (20 MHz, Volcano Corp., Rancho Cordova, USA). Following IVUS-VH acquisition, and after the disengagement and re-engagement of the guiding catheter, an additional acquisition was performed using a new IVUS catheter. Fifteen patients with 16 non-significant lesions were assessed by 2 independent observers. The relative inter-catheter differences regarding geometrical measurements were negligible for both observers. The inter-catheter relative difference in plaque cross-sectional area (CSA) was 3.2% for observer 1 and 0.5% for observer 2. The limits of agreement for (observer 1 measurements) lumen, vessel, plaque and plaque burden measurements were 0.82, -1.10 mm(2); 0.80, -0.66 mm(2); 1.08, -0.66 mm(2); and 5.83, -3.89%; respectively. Limits of agreement for calcium, fibrous, fibrolipidic and necrotic core CSA measurements were 0.22, -0.25 mm(2); 1.02, -0.71 mm(2); 0.61, -0.65 mm(2); and 0.43, -0.38 mm(2) respectively. Regarding the inter-observer agreement, the limits of agreement for lumen, vessel, plaque and plaque burden measurements were 2.61, -2.09 mm(2); 2.20-3.03 mm(2); 1.70, -3.04 mm(2); and 9.16, -16.41%; respectively, and for calcium, fibrous, fibrolipidic and necrotic core measurements of 0.08, -0.09 mm(2); 0.89, -1.28 mm(2); 0.74, -1.06 mm(2); and 0.16, -0.20 mm(2); respectively.


CONCLUSIONS
The present study demonstrates that the geometrical and compositional output of IVUS-VH is acceptably reproducible.
Department of Interventional Cardiology of the Erasmus Medical Center, Rotterdam, The Netherlands.
Gastón A
GA
Rodriguez-Granillo
Sophia
S
Vaina
Héctor M
HM
García-García
Marco
M
Valgimigli
Eric
E
Duckers
Robert J
RJ
van Geuns
Evelyn
E
Regar
William J
WJ
van der Giessen
Marco
M
Bressers
Dick
D
Goedhart
Marie-Angele
MA
Morel
Pim J
PJ
de Feyter
Patrick W
PW
Serruys
D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D012107:Research Design; D018084:Ultrasonography, Interventional / Q000295:instrumentation*