Restenosis of peripheral stents and stent grafts as revealed by intravascular sonography: in vivo comparison with angiography.

OBJECTIVE

Our objective was to compare intravascular sonography with digital subtraction angiography (DSA) in the assessment of luminal dimension and morphologic features of endovascular stents and stent grafts.

MATERIALS AND METHODS

Thirty-seven pelvic and 24 femoral stents (12 Wall-stents; 27 covered and 22 uncovered nitinol stents) in 50 patients were evaluated 15 +/- 10 months after implantation by DSA and intravascular sonography. The degree of maximum instent restenosis as revealed by DSA and intravascular sonography was compared for each location. Morphologic features of the stents and stenoses were also assessed.

RESULTS

Intravascular sonography and DSA correlated well (R2 = .96) in determining in-stent restenosis. In-stent restenosis was underestimated by 13% +/- 6% by DSA compared with intravascular sonography. Differences in determining in-stent restenosis with intravascular sonography and DSA were not associated with severity of stenosis or type of stent. Intravascular sonography revealed incomplete expansion of stents in 21 cases, whereas DSA revealed incomplete expansion of stents in seven cases. The intra- and interobserver variabilities in our study were 4% and 5%, respectively.

CONCLUSION

In-stent restenoses are underestimated with DSA. Intravascular sonography is superior to DSA for detection of incomplete stent expansion.