RESTENOSIS AFTER PERCUTANEOUS TRANSLUMINAL ANGIOPLASTY

BACKGROUND: Determine the feasibility of studying the natural history of the atherosclerotic plaque following percutaneous transluminal angi oplasty (PTA), using duplex scanning. METHODS: Twenty-three patients w ith 40 stenoses (>70% and <5 cm in length) in the iliac and femoro-pop liteal segments were studied by duplex scanning before PTA, on day 1, weekly for 8 weeks, and at 3 months, 6 months, and 1 year. The followi ng measurements were made: thickness of the plaque, minimal lumen diam eter (MLD), and peak systolic velocity ratio (PSVR). A PSVR >2.0 was u sed to indicate >50% lumen diameter reduction. RESULTS: Thirty stenose s were available for measurement and analysis. Mean reduction in plaqu e thickness after angioplasty was greater in echolucent plaques (2.33 +/- 0.9 mm) than echogenic plaques (0.83 +/- 0.6 mm; P <0.0001). Succe ssful angioplasty (PSVR <2.0) and increase in MLD in echolucent plaque s was the result of plaque compression; in echogenic plaques, of wall dilatation. The incidence of restenosis (PSVR >2.0) at 6 months was 12 of 30 (40%) remaining unchanged at 1 year; of the lesions that resten osed, 33% recurred before week 8 and the remainder between weeks 8 and 24, suggesting different mechanisms. During follow-up, all plaques sh owed ''growth''; <2 mm in 17 (57%; group A) and >2 mm in the remaining 13 (43%; group B). The incidence of restenosis (PSVR >2.0) was 4 of 1 7 (23%) in group A and 8 of 13 (61%) in group B (P <0.05). CONCLUSION: Duplex scanning provides valuable information on both luminal diamete r and plaque thickness; it may be used to study the natural history of plaques following angioplasty and also the effects of therapeutic age nts aimed at reducing restenosis. Am J Surg. 1998;176:102-108. (C) 199 8 by Excerpta Medica, Inc.