Hypercoagulability and platelet inhibition after OPCAB: randomized intervention with clopidogrel. Scand Cardiovasc J. 2007;41:325 330. doi: 10.1080/14017430701383763. 66. Mannacio VA, 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 1715. doi: 10.1136/heartjnl-2012-302449. 67. Gohlke H, Gohlke-B rwolf C, St rzenhofecker P, G rnandt L, Ritter B, Reichelt M, Buchwalsky R, Schmuziger M, Roskamm H. Improved graft patency with anticoagulant therapy after aortocoronary bypass surgery: a prospective, randomized study. Circulation. 1981;64(pt 2):II22 II27. 68. Post Coronary Artery Bypass Graft Trial Investigators. The effect of aggressive lowering of low-density lipoprotein cholesterol levels and low- dose anticoagulation on obstructive changes in saphenous-vein coronary- artery bypass grafts. N Engl J Med. 1997;336:153 162. 69. Wann LS, Curtis AB, January CT, Ellenbogen KA, Lowe JE, Estes NA 3rd, Page RL, Ezekowitz MD, Slotwiner DJ, Jackman WM, Stevenson WG, Tracy CM, Fuster V, Ryd n LE, Cannom DS, Le Heuzey JY, Crijns HJ, Lowe JE, Curtis AB, Olsson S, Ellenbogen KA, Prystowsky EN, Halperin JL, Tamargo JL, Kay GN, Wann L, Jacobs AK, Anderson JL, Albert N, Hochman JS, Buller CE, Kushner FG, Creager MA, Ohman EM, Ettinger SM, Stevenson WG, Guyton RA, Tarkington LG, Halperin JL, Yancy CW; ACCF/AHA Task Force Members. 2011 ACCF/AHA/ HRS focused update on the management of patients with atrial fibril- lation (updating the 2006 guideline): a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2011;123:104 123. doi: 10.1161/ CIR.0b013e3181fa3cf4. 70. Guyatt GH, Akl EA, Crowther M, Gutterman DD, Schuunemann HJ; American College of Chest Physicians Antithrombotic Therapy and Prevention of Thrombosis Panel. 