Target Doses of Secondary Prevention Medications Are Not Being Achieved in Patients With Reduced Left Ventricular Ejection Fraction After Acute Coronary Syndrome (ANZACS-QI 34)

Background Patients with reduced left ventricular ejection fraction (EF<40%) are at high risk for adverse outcomes and benefit from evidence based doses of angiotensin converting enzyme inhibitors (ACEi), angiotensin II receptor blockers (ARB) and beta blockers. Our aim was to investigate the dispensing and uptitration of these medications following acute coronary syndrome (ACS), according to left ventricular ejection fraction. Methods Patients presenting with ACS who underwent coronary angiography during 2015 were recorded in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry. Medication dispensing data on discharge and at 1-year follow-up were obtained using anonymised linkage to the national pharmaceutical dataset. Doses of medications dispensed were compared to target doses recommended in clinical guidelines. Results 4,082 patients were included in the study, of whom 602 (15%) had reduced ejection fraction (rEF). More patients with rEF were prescribed ACEi/ARB on discharge compared to those with preserved ejection fraction (pEF) (89% vs. 68%). Beta blocker dispensing on discharge was also higher in the rEF group (94% vs. 83%). In the rEF subgroup, 76% were maintained on ACEi/ARB and 85% on beta blockers by 1 year of follow-up. However, at discharge only 31% and 29% were on >= 50% of target doses of ACEi/ARB and beta blocker doses respectively, and by 1 year this increased only slightly to 34% and 35% respectively. Conclusions There is suboptimal dispensing of evidence-based medications in the year following ACS. Further intervention is required to improve medication uptitration and adherence, particularly of beta blockers and ACEI/ARBs in those with reduced ejection fraction.