In the only randomized trial to date, Sjoland et al196 found no clinical benefit asso- ciated with a 2-year treatment with metoprolol after CABG. Compared with placebo, metoprolol did not reduce the inci- dence of repeat revascularization, unstable angina, nonfatal MI, or death.197 ACE inhibitors should also be considered for CABG patients after surgery, particularly for those with recent MI, LV dysfunction, diabetes mellitus, and chronic kidney dis- ease. The BP-lowering effect of ACE inhibitors is dependent on a patient s volume state, thus the basis for their frequent administration together with a diuretic.230 ACE inhibitor use can be associated with a syndrome of functional renal insuf- ficiency or hyperkalemia. This form of acute kidney injury develops shortly after the initiation of ACE inhibitor therapy but can be observed after months or years of therapy, even in the absence of prior ill effects. It may relate to the drug dose or level of hydration, as well as to the degree of small and large renal artery obstructive disease.231 An ARB may be considered as an alternative in an ACE inhibitor intolerant patient. Two randomized, controlled trials have studied the use of ACE inhibitors after CABG. In a 149-patient trial evaluating the use of quinapril after surgery, investigators noted a reduc- tion in the composite outcome of angina, death, MI, repeat revascularization, stroke, or transient ischemic attacks in patients who received quinapril for 1 year compared with pla- cebo (3.5% versus 15%, quinapril versus placebo; P=0.02).232 However, these findings were not confirmed in the larger, mul- ticenter Ischemia Management With Accupril Post-Bypass Graft via Inhibition of the Converting Enzyme (IMAGINE) trial of 2253 stable CABG patients. 