Clopidogrel After Surgical Coronary Revascularization Increases Venous Graft Patency

Abstract

I read with great interest the article by Ebrahimi and colleagues [1Ebrahimi R. Bakaeen F.G. Uberoi A. et al.Effect of clopidogrel use post coronary artery bypass surgery on graft patency.Ann Thorac Surg. 2014; 97: 15-21Abstract Full Text Full Text PDF PubMed Scopus (35) Google Scholar] regarding the effect of the combination of aspirin and clopidogrel on vein graft patency after coronary artery bypass grafting (CABG) surgery. In this observational analysis of data from the Randomized On and Off-Pump Bypass trial, the authors concluded that clopidogrel use after CABG did not significantly reduce the incidence of 1-year venous graft failure. A recent meta-analysis [2Nocerino A.G. Achenbach S. Taylor A.J. Meta-analysis of effect of single versus dual antiplatelet therapy on early patency of bypass conduits after coronary artery bypass grafting.Am J Cardiol. 2013; 112: 1576-1579Abstract Full Text Full Text PDF PubMed Scopus (53) Google Scholar] of five randomized controlled studies investigating the effect of single versus dual antiplatelet therapy on early patency of graft conduits after CABG concluded that dual antiplatelet therapy significantly reduced the risk of venous graft occlusion. It is important to note that for vein grafts, single antiplatelet therapy was associated with a significantly increased graft failure rate (91 of 846; 10.8%) versus dual antiplatelet therapy (57 of 860; 6.6%; p = 0.003). In the latest guidelines on myocardial revascularization from the European Society of Cardiology and the European Association for Cardio-Thoracic Surgery [3Kolh P. Wijns W. Danchin N. et al.Task Force on Myocardial Revascularization of the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS); European Association for Percutaneous Cardiovascular Interventions (EAPCI)Guidelines on myocardial revascularization.Eur J Cardiothorac Surg. 2010; 38: S1-S52PubMed Google Scholar], the task force authors recommend the use of clopidogrel after CABG only in cases of aspirin intolerance because there are no randomized controlled trial comparing the efficacy of clopidogrel plus aspirin versus aspirin alone on graft patency. With the present strong and persuasive scientific evidence, this statement is now outdated. Grafts are especially vulnerable in the early postoperative period, and effective prompt postoperative antiplatelet therapy is paramount to preserve the revascularization benefit [4Gluckman T.J. McLean R.C. Schulman S.P. et al.Effects of aspirin responsiveness and platelet reactivity on early vein graft thrombosis after coronary artery bypass graft surgery.J Am Coll Cardiol. 2011; 57: 1069-1077Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar]. This underscores the importance of rapid identification of patients with aspirin resistance, thus allowing a timely intervention. The beneficial effect of clopidogrel is attributable to the fact that dual antiplatelet therapy overcomes single drug resistances as shown in the CRYSSA (prevention of coronary artery bypass occlusion after off-pump procedures) trial [5Mannacio V.A. Di Tommaso L. Antignan A. De Amicis V. Vosa C. Aspirin plus clopidogrel for optimal platelet inhibition following off-pump coronary artery bypass surgery: results from the CRYSSA (prevention of Coronary arteRY bypass occlusion After off-pump procedures) randomised study.Heart. 2012; 98: 1710-1715Crossref PubMed Scopus (104) Google Scholar]. Effect of Clopidogrel Use Post Coronary Artery Bypass Surgery on Graft PatencyThe Annals of Thoracic SurgeryVol. 97Issue 1PreviewClopidogrel use post coronary artery bypass grafting (CABG) has become more popular under the assumption that it improves graft patency. The purpose of this sub-analysis from the Randomized On and Off-Pump Bypass (ROOBY) trial is to evaluate the role of clopidogrel use post CABG to improve graft patency when added to standard aspirin therapy. Full-Text PDF