Objective: To determine the effect of preoperative therapy with angiotensin-converting enzyme (ACE) inhibitors on clinical outcome after cardiovascular surgery.
Study: Inception cohort.
Setting: A tertiary care 54-bed cardiothoracic ICU.
Patients: All admissions to an ICU over a 42-month period after cardiovascular surgery.
Intervention: Extraction of preoperative, operative, and ICU data from a database.
Outcome measures: Incidence of acute organ dysfunction, length of mechanical ventilation, ICU stay, and death after cardiovascular surgery.
Results: The study cohort consisted of four groups: normal or moderately impaired left ventricular function control (group A, n=6,400); normal or moderately impaired left ventricular function treated with ACE inhibitors (group B, n=1,375); severe left ventricular dysfunction control (group C, n=1,905); and severe left ventricular dysfunction treated with ACE inhibitors (group D, n=1,650). The incidence of three or more organ dysfunction was similar on comparison of group A vs group B (5% vs 6%) or group C vs group D (15% vs 13%). There were no differences in the total duration of mechanical ventilation or length of stay in the ICU in group A vs group B or group C vs group D. Death occurred in 2% of groups A and B, and at 6% in groups C and D. Preoperative severe left ventricular dysfunction in both groups C and D was associated with an increased incidence of three or more organ dysfunction, duration of mechanical ventilation, length of stay in ICU, and death after surgery. Multivariate analysis indicated that therapy with ACE inhibitors did not affect the clinical outcome after cardiovascular surgery.
Conclusion: Preoperative therapy with ACE inhibitors did not influence the clinical outcome after cardiac surgery. It is unlikely that therapy with ACE inhibitors can alter the clinical sequelae of cardiopulmonary bypass and cardiac surgical procedures performed in high-risk patients because of underlying severe left ventricular dysfunction.