Intravascular sonographic evaluation of iliac artery angioplasty: what is the mechanism of angioplasty and can intravascular sonography predict clinical outcome?

OBJECTIVE

The purpose of this study was to establish the arterial responses of the iliac artery after percutaneous transluminal angioplasty (PTA), using intravascular sonography, and to correlate intravascular sonography parameters with clinical outcome.

SUBJECTS AND METHODS

The study included 21 patients studied with intravascular sonography before and after PTA of the iliac artery. Distinction was made between intravascular sonography cross sections collected from the common iliac and those from the external iliac artery. First, qualitative and quantitative intravascular sonography data obtained at the most stenotic site were compared with data derived from all corresponding cross sections of the dilated segment. Second, the predictive value of intravascular sonography parameters for the patient outcome was assessed.

RESULTS

The free lumen and media-bounded areas seen in the common iliac artery were larger than those seen in the external iliac artery. Qualitative and quantitative effects of PTA observed with intravascular sonography on the two types of artery were not different. Vascular damage occurred in 81% of the patients. The frequency of vascular damage at the most stenotic site was slightly lower than in each dilated segment studied. The reduction in area stenosis after intervention was associated with an increase in the free lumen and media-bounded areas, whereas the plaque area reduced only slightly. The increase in the free lumen and media-bounded areas and the decrease in the plaque area at the most stenotic site after intervention were larger than the mean values. Qualitative data seen with intravascular sonography at the most stenotic site before and after intervention were not predictive of the patient outcome. In patients with an uneventful outcome after intervention, the free lumen area measured at the most stenotic site after PTA was larger and the area stenosis was smaller than in patients with a failure.

CONCLUSION

This study of intravascular sonography established that although the common iliac artery is larger than the external iliac artery, the qualitative and quantitative effects of PTA in both types of artery were similar. The size of the free lumen area and the degree of stenosis seen with intravascular sonography after PTA at the most stenotic site may be predictive of a patient outcome.