Contemporary Audit of Prescribing Patterns Following Coronary Artery Bypass Grafting

Abstract

Background: Coronary artery bypass grafting (CABG) candidates have significant risk for future cardiovascular events. Guidelines recommend aspirin and statins for all CABG patients, P2Y12 inhibitors for those after acute coronary syndrome (ACS), and beta blockers and angiotensin-converting enzyme (ACE) inhibitors for those with impaired ejection fraction <40%. This study audited the prescribing patterns following CABG performed at Auckland City Hospital. Methods: Consecutive patients who underwent CABG during the period July 2017–February 2018 were prospectively collected. Medications prescribed at discharge of index CABG admission and first cardiology clinic follow-up were reviewed. Results: The mean age was 65 ± 9 years, 57 (19%) were female, and operative mortality was seven (2.3%) in the 298 CABG patients who were audited. Prescription rates at discharge (n = 292) and clinic follow-up (n = 242) were: aspirin 97% and 98%; statins 98% and 99%; P2Y12 inhibitors 3% and 10%; beta blockers 77% and 75%; ACE inhibitors or ARB blockers 52% and 64%; anticoagulants 10% and 7%; amiodarone 28% and 2%; and proton-pump inhibitors 80% and 59%, respectively. P2Y12 inhibitors were only prescribed in 8 of 189 (4%, six ticagrelor) and 22 of 158 (14%, 13 ticagrelor), respectively, of ACS patients (n = 194). Beta blockers were prescribed in 44 of 55 (80%) and 36 of 47 (77%), and ACE inhibitors or ARB blockers in 35 of 55 (64%) and 33 of 47 (70%), respectively, of patients with ejection fractions <40% (n = 58). Conclusion: P2Y12 inhibitors were rarely prescribed for ACS patients after CABG, highlighting a lack of awareness of the evidence-base and guideline recommendations. Aspirin and statins were prescribed in almost all CABG patients, while beta blockers and ACE inhibitors were prescribed in most patients with impaired ejection fractions, but with room for improvement.