Table 2:

Therapeutic strategies for preventing arterial graft spasm and graft atherogenesis after coronary artery bypass grafting

Agent	Mechanisms of action	Time of initiation after CABG and treatment duration	Main study findings	Strength of evidence
Vasospasm prevention
Amlodipin, diltiazem	Calcium channel antagonist	Treatment duration 1 year	↓ incidence of RA occlusion	Observational32
Inhibition of platelet aggregation
Aspirin	Cyclooxygenase inhibition	Within 24 h (ideally with 6 h) after CABG and continued indefinitely	↓ incidence of SVG occlusion	Multiple RCTs and MAs of RCTs122–124
Clopidogrel	Irreversible P2Y12 receptor inhibitor	Variable timing of post-operative initiation; treatment duration 3–12 months	↓ incidence of SVG failure or occlusion Conflicting findings with regard to incidence of major bleeding	Several study-level MA of small RCTs and observational studies125–127
Ticagrelor	Reversible P2Y12 receptor inhibitor Pleiotropic effects including attenuation of ischaemia–reperfusion injury, inflammation, and atherosclerosis128	Within 48 h after CABG and continued for 1 year	↓ incidence of SVG failure ↑ incidence of BARC types 2, 3, 5 bleeding, no difference in incidence of BARC types 3 and 5 bleeding compared with aspirin alone	Single RCT of 500 patients,129 study-level MA of RCTs,125 IPD-MA of RCTs130
LDL-C-lowering
Statins	HMG-CoA reductase inhibition Pleiotropic effect on inflammation	Continued peri-operative treatment to LDL-C target level	↓ progression of graft atherosclerosis	One large RCT131

BARC, Bleeding Academic Research Consortium; CABG, coronary artery bypass grafting; HMG-CoA, hydroxy-methylglutaryl coenzyme A; MA, meta-analysis; RA, radial artery; RCT, randomized clinical trial; SVG, saphenous vein graft.