Use of intravascular ultrasound in the endovascular management of atherosclerotic aortoiliac occlusive disease

BACKGROUND: Intravascular ultrasound (IVUS) has been described as interesting technology in search of a clinical application by some and by others as a valuable diagnostic tool for many endovascular interventions. Its clinical usefulness has yet to be fully defined. When used during endovascular interventions, it can provide structural and diagnostic information, assess effectiveness of the therapy, and identify treatment-related complications. METHODS: Thirty-two consecutive patients with atherosclerotic aortoiliac occlusive disease who presented with 40 separate arterial lesions were evaluated with IVUS before and after balloon angioplasty and intraluminal stent placement. Information obtained from IVUS was compared with similar data obtained from simultaneous angiographic images. Both techniques were evaluated with respect to assessment of vessel size, lesion location, adequacy of therapy, and identification of complications. RESULTS: Real time IVUS imaging compared with angiographic imaging showed that in 62% of the patients, vessel diameter was underassessed using angiographic criteria alone. More importantly, 40% (16 of the 40 lesions) had underdeployed stents by IVUS evaluation that appeared adequately expanded by angiographic criteria. Further stent expansion with a larger balloon was necessary to achieve accurate stent to vessel wall apposition, This was found to be significant by an exact binomial 95% confidence interval. Incomplete stent deployment has been identified as a possible cause for restenosis and vessel occlusion. Information obtained from IVUS imaging substantially altered the endovascular therapy in approximately 40% of our patients and provided valuable vessel sizing and lesion composition information in 62% of the patients. CONCLUSION: Intravascular ultrasound can provide important diagnostic information that can alter the conduct of selected endovascular procedures. It is especially useful when the procedure requires deployment of arterial stents. By Excerpta Medica, Inc.