Impact of metoprolol standard dosing pathway in Chinese patients with acute coronary syndrome: protocol for a multicentre prospective study

INTRODUCTION: Metoprolol is the most frequently used β-receptor blockers; however, the prescribed dose in China is far less than the recommended doses in the guidelines. Based on the Chinese and International guidelines and the Chinese clinical practice, we are conducting this study (NCT03413410) to test the feasibility and tolerability of the metoprolol optimal dosing pathway by observing the percentage of patients achieving target dose in Chinese acute coronary syndrome (ACS) patients during hospitalisation. METHODS AND ANALYSIS: A total of about 1000 patients aged ≥18 years, hospitalised for ACS will be enrolled from ~15 hospital sites in China between February 2018 and April 2019. The percentage of patients achieving the target metoprolol dosage at discharge is the primary endpoint. The secondary endpoints included the following: mean heart rate (HR) and blood pressure (BP) of the patients who have achieved target dose at discharge and during the follow-up period, percentage of patients experiencing bradycardia (HR <50 beats/min), hypotension (BP <90/60 mm Hg) and drug-related temporary heart failure worsening during hospitalisation and 1 month after discharge, respectively. We will also assess the proportion of patients reporting metoprolol-related adverse events and the leading causes for metoprolol discontinuation. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ethics committee of the Chinese PLA General Hospital (number: S2017-112-01). Study findings will be disseminated through presentations at national and international conferences and submitted for publications in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov registry (NCT03413410).