title: Bailout intravenous esmolol for heart rate control in cardiac computed tomography angiography.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of a heart rate (HR) reduction protocol using intravenous esmolol as bailout for failed oral metoprolol regimens in patients undergoing coronary computed tomography angiography (CCTA) with 64-slice multidetector computed tomography (64-MDCT).
  
  
  METHODS
  Patients who underwent cardiac 64-MDCT in a single institution between 2011 and 2014 were analyzed. Those with HR above 60 beats per minute (bpm) on presentation received oral metoprolol (50-200 mg) at least one hour before CCTA. Intravenous esmolol 1-2 mg/kg was administered as a bolus whenever HR remained over 65 bpm just before imaging. The primary efficacy endpoint was HR <65 bpm during CCTA. The primary safety endpoint was symptomatic hypotension or bradycardia up to hospital discharge.
  
  
  RESULTS
  During the study period CCTA was performed in 947 cases. In 86% of these, oral metoprolol was the only medication required to successfully reduce HR <60 bpm. Esmolol was used in the remaining 130 patients (14%). For esmolol-treated patients mean baseline and acquisition HR were 74±14 bpm and 63±9 bpm, respectively (p<0.001). The target HR of <65 bpm was achieved in 82 of the 130 esmolol-treated patients (63%). Considering the whole population, esmolol use led to a significant increase in the primary efficacy endpoint from 86% to 95% (p<0.001). Esmolol also resulted in a statistically, but not clinically, significant reduction in systolic blood pressure (144±22 to 115±17 mmHg; p<0.001). The combined primary safety endpoint was only observed in two (1.5%) patients.
  
  
  CONCLUSIONS
  Despite optimal use of oral beta-blockers, 14% of patients needed intravenous esmolol for HR control. The pre-medication combination of oral metoprolol and on-demand administration of intravenous esmolol was safe and effective and enabled 95% of patients to be imaged with HR below 65 bpm.
authors.affiliation: Cardiology Department, Santa Marta Hospital, Lisbon, Portugal. Electronic address: silviaguiarosa@gmail.com.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Aguiar Rosa
authors.affiliation: Cardiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Ruben
authors.initials: R
authors.lastname: Ramos
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Hugo
authors.initials: H
authors.lastname: Marques
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Rosana
authors.initials: R
authors.lastname: Santos
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Cecília
authors.initials: C
authors.lastname: Leal
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Casado
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Márcia
authors.initials: M
authors.lastname: Saraiva
authors.affiliation: Radiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Luísa
authors.initials: L
authors.lastname: Figueiredo
authors.affiliation: Cardiology Department, Santa Marta Hospital, Lisbon, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Cruz Ferreira
mesh_terms: D058671:Adrenergic beta-1 Receptor Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000627:therapeutic use; D017023:Coronary Angiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008790:Metoprolol / Q000627:therapeutic use; D061330:Multidetector Computed Tomography; D011412:Propanolamines / Q000008:administration & dosage / Q000627:therapeutic use*; D016879:Salvage Therapy; D017211:Treatment Failure
chemical_list: D058671:Adrenergic beta-1 Receptor Antagonists; D000889:Anti-Arrhythmia Agents; D011412:Propanolamines; D008790:Metoprolol; C036604:esmolol
keywords: Angiografia coronária por tomografia computorizada; Controlo de frequência cardíaca; Coronary computed tomography angiography; Esmolol; Heart rate control