INCIDENCE, OUTCOME AND PREDICTION OF EARLY CLINICAL EVENTS FOLLOWING PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY - A COMPARISON BETWEEN TREATMENT WITH REVIPARIN AND UNFRACTIONATED HEPARIN PLACEBO (RESULTS OF A SUBSTUDY OF THE REDUCE TRIAL)/

Background Unfractionated heparin and its low molecular weight fragmen ts possess antithrombotic properties, properties that are routinely ex ploited in coronary angioplasty (PTCA). Objectives In the setting of t he REDUCE trial, a randomized, double-blind, multicentre trial, the oc currence of acute or early clinical events was compared in patients tr eated with either unfractionated heparin/placebo or low molecular weig ht heparin (reviparin). Methods and Results Six hundred and twelve pat ients with native coronary artery obstructions randomized between unfr actionated heparin/placebo and reviparin, were analysed. Baseline char acteristics were similar in both groups. Using the intention-to-treat analysis, major acute or early events (myocardial infarction, re-PTCA, bypass surgery, death) occurred in 42 patients (7%), 29 in the contro l group and 13 in the treatment group (P = 0.027). In order to develop a predictive model for the risk of early events following coronary ba lloon angioplasty, clinical as well as pre-PTCA and procedural charact eristics were analysed. Thrombi at the treated lesion site (P = 0.02), dissection (P < 0.001), lesion type B-2 and C according to the NHLBI classification (P < 0.001), diameter stenosis > 50% post-PTCA (P < 0.0 01), and length of stenosis > 20 mm (P = 0.005) were significantly ass ociated with the occurrence of acute events. By multiple logistic regr ession analysis, in which these variables and the treatment regimen we re entered, dissection (P = 0.042), diameter stenosis > 50% (P < 0.028 ) and lesion type B-2 and C (P = 0.017) were found to be independently predictive of early adverse events. Bleeding complications were simil ar in the two treatment groups. Conclusions Reviparin, given in a very early stage of vascular injury, compares favourably with unfractionat ed heparin/placebo, by reducing abrupt closure and acute-phase adverse outcome following PTCA. With respect to the evaluated risk factors fo r acute events, the positive effect of reviparin on early adverse outc ome after PTCA may be due to improved antithrombotic properties as com pared to unfractionated heparin.