Outcomes of Angiotensin Converting Enzyme Inhibitor Management Strategies Prior to Coronary Artery Bypass
Outcomes of Angiotensin Converting Enzyme Inhibitor Management Strategies Prior to Coronary Artery Bypass
Coronary artery disease is a leading cause of death, hospitalization, and health care costs
 in developed nations. Coronary revascularization with coronary artery bypass graft (CABG)
 surgery improves the long term survival in patients with diabetes and multi-vessel disease.
 Angiotensin converting enzyme inhibitors (ACE) and angiotensin receptor blockers (ARB) reduce
 mortality and subsequent cardiac events in patients with coronary artery disease undergoing
 CABG surgery when initiated at least 4 weeks pre-operatively. Observational data have
 suggested that pre-operative ACE administration is associated with an increased risk of
 post-operative vasoplegic shock, acute kidney injury, and mortality; however, other studies
 have failed to confirm these findings and further suggested ACE are associated with a reduced
 risk of peri-operative myocardial infarction. A single trial of 40 CABG patients randomized
 to pre-operative ACE withdrawal or continuation reported that the withdrawal group required
 significantly fewer vasopressors during cardiopulmonary bypass but more intravenous
 vasodilators post-operatively to control hypertension. Hence, it remains unclear whether ACEs
 should be held or continued immediately prior to CABG surgery and a survey of cardiac
 surgeons suggests that current clinical practice is divided. This pilot study aims to
 establish the feasibility of the study design and to determine the frequency of clinical
 endpoints among patients who continue and discontinue ACE prior to cardiac surgery.
Inclusion Criteria:

 -  Patients undergoing elective or urgent isolated CABG and/or valvular repari or
 replacement surgery

 -  On an ACE or ARB for a minimum of 7 days

 Exclusion Criteria:

 -  Emergency surgery

 -  Pre-operative shock (defined as systolic blood pressure < 90 mmHg, the need for any
 vasopressor or inotropic support, or a mechanical cardiac support device)

 -  Severe uncontrolled pre-operative hypertension (defined as blood pressure ≥ 200 mmHg
 systolic or ≥120mmHg diastolic mmHG or the pre-operative need for intravenous
 anti-hypertensive agents)

 -  ACE or ARB therapy < 7 days

 -  Any mineralocorticoid receptor antagonist therapy.