Dual quantitative coronary angiography: a novel approach to quantify intracoronary thrombotic burden.
OBJECTIVE
To validate and test in vivo a new modality of quantitative coronary angiography (QCA), dual QCA (D-QCA), developed to quantify intracoronary thrombotic burden (ITB).


RESULTS
Calculation of ITB with D-QCA is based on the discrepancy of luminal areas assessed with edge detection (ED) and video-densitometry (VD), measured with Cardiovascular Angiography Analysis System II. Experimental validation was first performed in phantoms with known obstructive volumes. In vivo assessment of thrombotic burden changes was performed in angiograms from 19 patients with large ITB, obtained before and after antithrombotic treatment, and compared with semi-quantitative assessment (TIMI thrombus grade (TTG)). A good correlation between D-QCA and true occlusive volumes was found (y = 9.21+0.99x, r = 0.996). Intra- and inter-observer variability was 2.77 +/- 10.97 mm3 (p = 0.50) and -1.28 +/- 6.99 mm3 (p = 0.62) respectively. In vivo, D-QCA demonstrated a significant reduction in ITB resulting from treatment (137.22 +/- 120.13 mm3 before and 104.72 +/- 99.19 mm3 after treatment, p = 0.001). Overall, TTG also decreased (3.63 +/- 0.68 before and 3.11 +/- 1.20 after, p = 0.008), but in those nine (47%) patients in which remained unchanged D-QCA detected a reduction in ITB (pre 148.17 +/- 154.03 mm3, post 112.86 +/- 117.82 mm3, p = 0.05).


CONCLUSIONS
D-QCA appears as a useful approach to quantify IC thrombus volume, being more sensitive than TTG in assessing changes in ITB resulting from treatment strategies.
Aleong
Godfrey
G
Cardiovascular Institute, Hospital Clínico San Carlos, Madrid, Spain.
Vaqueriza
David
D
Del Valle
Raquel
R
Garcia
Hiram
H
Hernandez
Rosana
R
Alfonso
Fernando
F
Jimenez-Quevedo
Pilar
P
Bañuelos
Camino
C
Macaya
Carlos
C
Escaned
Javier
J
D000368:Aged; D000369:Aged, 80 and over; D017023:Coronary Angiography / Q000295:instrumentation / Q000379:methods*; D003328:Coronary Thrombosis / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D003720:Densitometry; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D016896:Treatment Outcome
D005343:Fibrinolytic Agents