Stent gap by 64-detector computed tomographic angiography relationship to in-stent restenosis, fracture, and overlap failure.
OBJECTIVE
The goal of this study was to define the frequency of stent gaps by 64-detector computed tomographic angiography (CTA) and their relation to in-stent restenosis (ISR), stent fracture (SF), and overlap failure (OF).


BACKGROUND
SF defined by catheter angiography or intravascular ultrasound has been implicated in ISR.


METHODS
A total of 292 consecutive patients, with 613 stents, who underwent CTA were evaluated for stent gaps associated with decreased Hounsfield units. Correlations with catheter coronary angiography (CCA) were available in 143 patients with 384 stents.


RESULTS
Stent gaps were noted in 16.9% by CTA and 1.0% by CCA. ISR by CCA was noted in 46.1% of the stent gaps (p < 0.001) as determined by CCA, and stent gaps by CTA accounted for 27.8% of the total ISR (p < 0.001). In univariate analysis, stent diameter > or =3 mm was the only CCA characteristic significantly associated with stent gaps (p = 0.002), but was not a significant predictor by multivariate analysis. Bifurcation stents, underlying calcification, stent type, location, post-dilation, and overlapping stents were not observed to be predisposing factors. Excessive tortuosity and lack of conformability were not associated with stent gaps; however, their frequency was insufficient to permit meaningful analysis.


CONCLUSIONS
Stent gap by CTA: 1) is associated with 28% of ISR, and ISR is found in 46% of stent gaps; 2) is associated with > or =3-mm stents by univariate (p = 0.002) but not by multivariate analysis; 3) is infrequently noted on catheter angiography; and 4) most likely represents SF in the setting of a single stent, and may represent SF or OF in overlapping stents.
Hecht
Harvey S
HS
Lenox Hill Heart & Vascular Institute, New York, New York, USA. hhecht@aol.com
Polena
Sotir
S
Jelnin
Vladimir
V
Jimenez
Marcelo
M
Bhatti
Tandeep
T
Parikh
Manish
M
Panagopoulos
Georgia
G
Roubin
Gary
G
D000328:Adult; D000368:Aged; D017023:Coronary Angiography / Q000379:methods*; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D015203:Reproducibility of Results; D012189:Retrospective Studies; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*