[Evaluation of the lumen-plaque-wall alterations by intravascular ultrasound imaging after percutaneous transluminal laser angioplasty in peripheral arteries: comparison with angiographic findings].

Intravascular ultrasound imaging was compared to angiography for evaluation of the changes in arterial lumen, atherosclerotic plaque and arterial walls after percutaneous transluminal laser angioplasty (PTLA) in peripheral arteries. Seventeen procedures using an argon laser angioplasty system (LASTAC system II) were performed in 13 patients with totally occluded lesions in the superficial femoral and iliac arteries. During or immediately after PTLA, a 30 MHz intravascular ultrasound catheter was inserted into the channel created by laser irradiation and adjunctive balloon dilatation. The outcome of PTLA was considered morphologically successful if the residual stenosis measured by intravascular ultrasound was 75% or less. Intravascular ultrasound showed eccentric plaques in 12 (71%), calcified plaques in 11 (65%), intraluminal thrombi in 2 (12%) and arterial wall injuries in 13 (76%) of the 17 lesions. PTLA was successful in 13 lesions and failed in 4. Occurrence of arterial dissections (38%) and mean residual stenoses (44 +/- 13%) were significantly (p < 0.05) lower in successful PTLA than in unsuccessful PTLA (100%, 89 +/- 3%). Eccentric stenoses, calcified plaques and arterial wall injuries were associated with poor success. Intravascular ultrasound detection of eccentric stenoses (71%), calcified plaques (65%) and arterial wall injuries (76%) was better than by angiography (29, 29, 47%). However, no significant correlation between intravascular ultrasound and angiographic findings could be found in quantitative estimation of the residual stenoses. Intraluminal thrombi were identified only by intravascular ultrasound. Angiography showed abnormalities in five (83%) of six lesions with medial injuries demonstrated by intravascular ultrasound, but none of the seven lesions with intimal injury. Intravascular ultrasound provides accurate diagnosis of eccentric stenosis, calcification, and arterial wall injury, and can quantitatively estimate residual stenosis and arterial wall injury during and immediately after PTLA in peripheral artery disease.