Pro: ACE Inhibitors Should Be Continued Perioperatively and Prior to Cardiovascular Operations.

Abstract

ECISIONS INVOLVING the initiation or discontinuation of any medical intervention should be undertaken only after careful consideration of all available evidence. The risks and benefits must be evaluated for each individual patient and circumstance, especially in situations where the evidence is not as clear as in the question about continuation of perioperative angiotensin-converting enzyme (ACE) inhibitors. Major medical societies such as the American College of Cardiology and American Heart Association (ACC/AHA) and European societies recommend continuation of ACE inhibitors in the perioperative period. 1,2 Based on currently available evidence, the authors agree with their recommendation and argue in support of the continuation of ACE inhibitors prior to cardiovascular operations. ACE inhibitors were first introduced to the general public in the early 1980s. Initially, dosing of the pilot drug captopril proved to be problematic and multiple studies showed profound hypotension when the drug was initiated. 3 As dosing adjustments were made and newer agents like enalapril were introduced, the real benefit of ACE inhibitors came to light. The CONSENSUS trial published in 1987 was a doubleblinded study in which 253 patients with severe congestive heart failure (New York Heart Association [NYHA] functional Class IV) were randomly assigned to conventional treatment plus placebo or conventional treatment plus enalapril. 4 Mortality after six months was 26% in the enalapril group and 44% in the placebo group, representing a 40% reduction in mortality. At 1 year, mortality was reduced 31% in the enalapril group as compared to the placebo group, and these patients were shown to have a reduction in left ventricular size and an improvement in their NYHA classification. Although the CONSENSUS trial demonstrates the value of ACE inhibitors in patients with severe heart failure, further studies also have proven their benefit in patients with less severe disease. In 1992, the SAVE trial randomized 2,231 patients from multiple centers who had suffered a myocardial infarction with ejection fractions of 40% or less and without heart failure symptoms to receive treatment with either placebo or captopril within 3 to 16 days after their myocardial infarction. 5 All-cause mortality was reduced by 19% in the captopril group. Furthermore, they found a 37% risk reduction from severe heart failure, a 22% risk reduction in heart failure requiring hospitalization, and a 25% risk reduction in recurrent myocardial infarction. Since then, it has been well established that ACE inhibitors reduce sudden cardiac death in patients with heart failure and prevent remodeling and dilation of the left ventricle that can occur after a myocardial infarc