How long should antithrombotic therapy be continued following aortocoronary bypass surgery?
Pfisterer, M.; Jockers, G.; Regenass, S.; Schmitt, H.E.; Grädel, E.; Burkart, F.
Schweizerische Medizinische Wochenschrift 119(43): 1518-1520
1989
ISSN/ISBN: 0036-7672 PMID: 2692145 Document Number: 340311
In a prospective randomized trial the effect of prolonged antithrombotic treatment with anticoagulants or antiplatelet drugs (50 mg aspirin + 400 mg dipyridamole daily) on late bypass-graft occlusion was studied. After 3 months active treatment was replaced by placebo in half of the patients. Between the angiographic checkups 2 weeks and 12 months postoperatively, 28/330 (8%) new graft occlusions had occurred on continued therapy, versus 44/319 (14%) on placebo (p = 0.03). This difference was most pronounced in individual grafts (6% vs 12%, p = 0.01), so that fewer patients with 12 months' active therapy had at least one occluded graft (22% versus 32%, p = 0.08). These findings suggest that antithrombotic treatment should not be halted 3 months after CABG surgery but should be continued for at least one year and possibly longer.