文摘
Intravascular ultrasound radiofrequency (RF-IVUS) data permit the analysis of coronary plaque composition in vivo and is used as an endpoint of ongoing pharmacological intervention trials. We assessed the reproducibility of volumetric RF-IVUS analyses in mild-to-moderately diseased atherosclerotic human coronary arteries in vivo. A total of 9,212 IVUS analyses on cross-sectional IVUS frames was performed to evaluate the reproducibility of volumetric RF-IVUS measurements in 33 coronary segments with a length of 27 ¡À 7 mm. For vessel, lumen, and plaque + media volume the relative measurement differences (P = NS for all) were (A = intraobserver comparison, same pullback) −0.40 ¡À 1.0 % ; −0.48 ¡À 1.4 % ; −0.35 ¡À 1.6 % , (B = intraobserver comparison, repeated pullback) −0.42 ¡À 1.2 % ; −0.52 ¡À 1.8 % ; −0.43 ¡À 4.5 % (C = interobserver comparison, same pullback) 0.71 ¡À 1.8 % ; 0.71 ¡À 2.2 % , and 0.89 ¡À 5.0 % , respectively. For fibrous, fibro-lipidic, calcium, and necrotic-core volumes the relative measurement differences (P = NS for all) were (A) 0.45 ¡À 2.1 % ; −1.12 ¡À 4.9 % ; −0.84 ¡À 2.1 % ; −0.22 ¡À 1.8 % , (B) 1.40 ¡À 4.1 % ; 1.26 ¡À 6.7 % ; 2.66 ¡À 7.4 % ; 0.85 ¡À 4.4 % , and (C) −1.60 ¡À 4.9 % ; 3.85 ¡À 8.2 % ; 1.66 ¡À 7.5 % , and −1.58 ¡À 4.7 % , respectively. Of note, necrotic-core volume showed on average the lowest measurement variability. Thus, in mild-to-moderate atherosclerotic coronary artery disease the reproducibility of volumetric compositional RF-IVUS measurements from the same pullback is relatively high, but lower than the reproducibility of geometrical IVUS measurements. Measurements from repeated pullbacks and by different observers show acceptable reproducibilities; the volumetric measurement of the necrotic-core shows on average the highest reproducibility of the compositional RF-IVUS measurements