Effectiveness of recombinant desulphatohirudin in reducing restenosis after balloon angioplasty of atherosclerotic femoral arteries in rabbits

• Published in: Circulation (New York, N.Y.) N.Y.), 1991-07, Vol.84 (1), p.232-243
• Main Authors: SAREMBOCK, I. J, GERTZ, S. D, GIMPLE, L. W, OWEN, R. M, POWERS, E. R, ROBERTS, W. C
• Format: Article
• Language: English
• Subjects: Angioplasty, Balloon; Animals; Arteriosclerosis - pathology; Arteriosclerosis - therapy; Biological and medical sciences; Blood. Blood coagulation. Reticuloendothelial system; Femoral Artery; Fibrinolytic Agents - pharmacology; Hirudins - analogs & derivatives; Hirudins - pharmacology; Male; Medical sciences; Pharmacology. Drug treatments; Rabbits; Recombinant Proteins - pharmacology; Recurrence; Thrombolytic Therapy
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.cir.84.1.232

The effectiveness of balloon angioplasty is limited by a restenosis rate of approximately 30%. Recombinant desulphatohirudin (r-hirudin [CGP 39393]) has been found to be highly effective in preventing acute platelet-rich thrombosis after deep arterial injury as compared with heparin. This study evaluated the effect of intravenous r-hirudin, a selective inhibitor of thrombin, on restenosis after balloon angioplasty in 29 rabbits. Focal femoral atherosclerosis was induced by air desiccation endothelial injury followed by a 2% cholesterol diet for 1 month. At angioplasty (2.5-mm balloon with three 60-second, 10-atm inflations 60 seconds apart), the rabbits received heparin (150 units/kg bolus, n = 16) or r-hirudin (1 mg/kg bolus followed by infusions of 1 mg/kg for the first hour and 0.5 mg/kg for the second hour, n = 13). Angiograms performed before and after angioplasty and before death were analyzed quantitatively by a blinded observer. Rabbits were killed 2 hours (n = 14) or 28 days (n = 15) after angioplasty. Femoral arteries were fixed in situ by perfusion of 10% formaldehyde at 100 mm Hg. The mean luminal diameter of the arteries with successful angioplasty (greater than or equal to 20% increase in luminal diameter) in rabbits treated with heparin (n = 8 arteries) increased from 1.18 +/- 0.29 mm before angioplasty to 1.86 +/- 0.24 mm immediately after angioplasty (p less than 0.001) and decreased to 0.94 +/- 0.69 mm (p = 0.0004) at 28 days after angioplasty. In rabbits treated with r-hirudin (n = 11 arteries), the mean luminal diameter increased from 1.14 +/- 0.17 mm before angioplasty to 1.68 +/- 0.20 mm immediately after angioplasty (p less than 0.001) and decreased to 1.37 +/- 0.47 mm (p = 0.01) at 28 days after angioplasty. The mean reduction in luminal diameter by angiography was less in the r-hirudin-treated group than in the heparin-treated group (0.30 +/- 0.33 versus 0.92 +/- 0.61 mm, p = 0.01). Blinded planimetric analysis of stained histological sections of the femoral arteries also showed less cross-sectional area narrowing by plaque in rabbits treated with r-hirudin compared with those treated with heparin (22 +/- 16% verus 48 +/- 29%, p = 0.01). Both groups had similar numbers of arteries with histological evidence of balloon-induced plaque tear (12 of 13 versus 13 of 15). Rabbits receiving r-hirudin at the time of experimental balloon angioplasty had significantly less restenosis by angiography and by quantitative histopathology than rabb