TYPE & CONSISTENCY OF ANTICOAGULANTS USED WITH ACUTE CORONARY SYNDROME PATIENTS IN NEW BRUNSWICK

Abstract

The Canadian Cardiovascular Society produces guidelines but lacks direction for anticoagulant use in high risk populations with Acute Coronary Syndrome. It is not certain which type and dose of anticoagulants are safer and effective in the elderly and renal insufficient population. With no provincial treatment strategies for ACS in New Brunswick we aimed to provide an overview of anticoagulation use among ACS patients referred to the New Brunswick Heart Centre. Patients were compared in regards to: anticoagulants prescribed in patients over age 75; dosage of anticoagulants in patients with low creatinine-clearance; Lovenox dose greater than 100mg; and, age distribution. A retrospective chart audit was obtained from the NBHC’s database of patients consulted for cardiac catheterization from 01 August 2012 until 31 October 2012 (N=544). Inclusion criteria included diagnosed of an ACS and referral to the NBHC for cardiac catheterization. Exclusion criteria included death at the referral hospital. Data collected included referral hospital, gender, age, weight, referring diagnosis, anticoagulation medication dose and frequency, and renal dysfunction. Overall the age distribution of patients on Lovenox (n=344, mean 63.5, SD 11.3) vs IV heparin (n=92, mean 69.8, SD 12.2); patients on Lovenox were younger than those on IV heparin (t-test p<0.0001). Our data demonstrated that of 75 patients with a diagnosis of a STEMI, 83% had either Lovenox withheld (placed on unfractionated heparin) or reduced as per guidelines, 17% receiving higher than recommended dosing. Data showed with referring hospitals, 48% of patients with creatinine-clearance 30-60 mL/min were given a dose less than weight but 2% of patients had dose reduction as low as 0.75mg/kg. At the SJRH tertiary care center, 60% of patients with mild renal insufficiency had reduced dose Lovenox with 40% having a dose of 0.75mg/kg. Only 3 patients had severe renal impairment (Creatine-clearance <30 mL/min), 2/3 were deferred Lovenox or prescribed Lovenox at a reduced dose as per CCS recommendations one case a patient received Lovenox at a dose higher than recommended. 2% out of the 350 patients on Lovenox were concurrently on two types of heparin during hospitalization. 6% of patients received Lovenox doses greater than the maximum recommendation. Fondaparinux, was prescribed once within the study population. Adopting a provincial anticoagulation protocol based on current CCS anticoagulation guidelines would decrease physician dosing errors resulting in a decrease in adverse events and in hospital stays thus decreasing the healthcare cost burden in the province of NB.