Does 111indium-platelet deposition predict patency in prosthetic arterial grafts?

Publisher Website
Google Scholar
Abstract
The relationship between the rate of 111In‐platelet deposition on vascular grafts and subsequent thrombosis has been examined in patients undergoing femoropopliteal by‐pass. Sixty‐seven patients undergoing femoropopliteal by‐pass using vein, Dacron or PTFE were randomized to aspirin plus dipyridamole (ASA/DPM) or placebo. Autologous 111In‐platelets were injected in the second postoperative week and Thrombogenicity Index (TI) calculated as the mean daily rise in the ratio of radioactivity graft/contralateral thigh. Graft patency was assessed to 1 year. Mean ( + s.e.m.) TI at 1 week in 21 grafts that occluded within 12 months was 0·19 ± 0·018 compared with 0·07 ± 0·009 in the 38 that remained patient (P < 0·001). Grafts with a TI less or greater than the median had a 90 per cent or 39 per cent cumulative 1‐year patency, respectively (P < 0·001). In the prosthetic grafts ASA/DPM reduced mean TI from 0·17 ± 0·02 to 0·11 ± 0·01 (P < 0·02) and enhanced 1‐year patency from 36 to 67 per cent (P < 0·05). Following femoropopliteal by‐pass TI related to subsequent graft patency. Radiolabelled platelet deposition therefore provides a guide as to how new materials or antithrombotic drugs may influence clinical graft thrombosis. Platelet inhibition reduced both graft thrombogenicity and subsequent occlusion.