241 Risk of supratherapeutic APTT in the absence of an initial unfractionated heparin bolus

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Abstracts

drug coverage program, which requires pre-authorization for clopidogrel coverage. METHODS: Challenges with pre-authorization were identified at a large tertiary centre in Western Canada. These challenges regarding the pre-authorization process included inconsistency in submission, delay in time to approval and lack of follow up. A condensed clopidogrel pre-authorization form was created by an interdisciplinary cardiac team and submitted to the provincial drug coverage program for every PCI patient. Each patient received a five day supply of clopidogrel, along with education on the importance of DAT. Information and instruction was provided to community pharmacists, allowing them to follow up with the cardiac program pharmacist if preauthorization was not approved. RESULTS: Over 90% of PCI patients experienced the benefit of the Clopidogrel Discharge Program. These benefits included receiving a five day supply of clopidogrel, education regarding the importance of DAT and assurance of approval of the preauthorization form. Approximately 3% of patients required cardiac pharmacist follow up with the provincial drug coverage program. CONCLUSION: Recognition of practice gaps is imperative in order to improve continuity of care and promote adherence to established standards of care. The Clopidogrel Discharge Program was designed and implemented to overcome identified challenges at a large tertiary centre. This program was successful in streamlining care by improving timely access and adherence to DAT.

241 RISK OF SUPRATHERAPEUTIC APTT IN THE ABSENCE OF AN INITIAL UNFRACTIONATED HEPARIN BOLUS

64% (subtherapeutic), 16% vs 17% (therapeutic), and 35% vs 19% (supratherapeutic; P ⫽ 0.03). Between 20 and 28 hours after starting UFH, subtherapeutic, therapeutic and supratherapeutic aPTT in group A versus group B were 49% vs 43%, 43% vs 38%, and 8% vs 19% (P ⫽ 0.05), respectively. Patients of both groups received a similar number of subsequent boluses during the first 24 hours of UFH protocols (24 vs. 28%; P ⫽ 0.51). Extrapolation of our results is limited by the fact that weight adjusted UFH bolus (standard of care) was used in 44% of the cohort. However, similar results were observed independently of adjustment of bolus dose by weight. CONCLUSION: In the absence of an initial UFH bolus, fewer patients have supratherapeutic aPTT and more patients have subtherapeutic results at 6 hours after starting UFH. However, at 24 hours, supratherapeutic aPTT are more frequently attained if initial bolus was omitted. This result raises a major issue because decision to omit initial bolus is generally based on a higher risk of bleeding. We suggest that this result could be explained by more frequent perfusion adjustments for patients not receiving an initial bolus. Further research could lead to practice changes in order to avoid excessive bleeding with UFH therapies.

242 MANAGEMENT AND OUTCOMES OF ACUTE CORONARY SYNDROME PATIENTS WITH A PRIOR HISTORY OF ATRIAL FIBRILLATION B Elbarouni, L Alshengeiti, RT Yan, FR Grondin, F Spencer, S Pallie, D Brieger, KA Eagle, I Mangat, S Singh, SG Goodman, AT Yan Toronto, Ontario

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and often occurs in patients with an acute coronary syndrome (ACS). We sought to determine (1) the prevalence of prior AF in a broad spectrum of patients admitted to hospital with ACS; (2) management patterns of ACS in patients with a prior history of AF; and, (3) In-hospital outcomes of ACS patients with a prior history of atrial fibrillation. METHODS: GRACE (Global Registry of Acute Coronary Events), its expansion GRACE2, and CANRACE (Canadian Registry of Acute Coronary Events), are prospective, multicenter registries of patients admitted with ACS. A total of 14285 patients with ACS were enrolled in the registries from June 1999 to December 2008 and were included in our study. We considered any prior history of AF regardless of the rhythm at ACS presentation. RESULTS: A total of 1333 (9.3%) patients had a history of AF. Patients with prior AF were older (median 77 vs. 65 years), more often female, and more likely to have a prior history of diabetes, hypertension, myocardial infarction, coronary revascularization and stroke (all P ⬍ 0.001). Prior AF was associated with a higher GRACE risk score (158 vs. 124, P ⬍ 0.001). Patients with prior AF were more likely to be on warfarin, BACKGROUND:

F Bonenfant, B Cossette, V Nault, M Turgeon, M Paulin, D Echenberg, P Charron, M Lépine, T Fayad, P Farand Sherbrooke, Québec BACKGROUND: Unfractionated heparin (UFH) is an anticoagulant commonly used in hospital settings. Decision to use an initial bolus is generally based on risk of bleeding. Little data are available to predict the effect of UFH bolus in achieving a therapeutic activated partial thromboplastin time (aPTT). Our objective was to assess the effect of an initial bolus of UFH on aPTT attained at 6 and 24 hours after starting UFH. METHODS/ RESULTS: We analyzed the records of all patients who received UFH in a tertiary care university hospital during two periods (May to August 2008 and July to August 2010). Data were collected for 371 patients, but only the 167 protocols (160 patients) with an aPTT available between 20 and 28 hours after the beginning of the UFH were included for analysis. Of these, an initial bolus of UFH was given in 86 UFH protocols (group A) versus no UFH bolus given in 81 protocols (group B). Groups were similar in terms of age and gender distribution. Indications for anticoagulation were mainly cardiac pathologies (87%). Between 5 and 7 hours after starting UFH, aPTT results in group A versus group B were: 49% vs