Guidelines for ED Coronary CTA 24/7 Program

UWMC-Montlake and HMC Emergency Departments

Summary:

  • Apply The ED Chest Pain Pathwaya Risk Calculatorb to confirm correct study.
  • Confirm inclusion and exclusion criteria to confirm correct patient.
  • Order the CCTA study and the study medications.
    • Call x43651 ‘After Hours’ to confirm capacity to interpret the study.
  • The CCTA study is performed and then interpreted.
  • Disposition patient accordingly per study interpretation.

 

ED providers should apply The ED Chest Pain Pathwaya Risk Calculatorb. This decision tool applies the Heart Score, the CAD Risk Calculator, and the Risk of In-Hospital Event by the Grace 2.0 Score to:

  • Stratify risk.
  • Recommend disposition versus expedited testing eligibility.
  • Recommend patient specific testing where appropriate.
    • Expedited testing may include Coronary CTA (CCTA), depending on the clinical scenario.
  • Allows automated scores and recommendations to be placed in the medical record (copy clipboard directly from the calculator and paste into chart).

Any ED use of CCTA as part of a combined protocol (i.e., ‘Triple Rule Out’ Protocol) must adhere to criteria for CCTA in general as per this protocol.

a https://occam.uwmedicine.org/media/2246/em_cards_cp_algo_hl_10_1_18.pdf

b www.hearttest.uw.edu, &/or http://depts.washington.edu/heartcds/cardiac_guide/ed_path/uwmc_ed_path_v7.html

 

ED CCTA Ordering:

Review Indications & Contraindications below to confirm patient eligibility for ED use of CCTA.

  • ‘Business Hours’ = Weekdays 7a-330p (excluding Holidays):
    • ED orders ‘CT Cardiac and CTA Coronary (aka CCTA)’ or ‘CTA Chest Triple Rule Out’.
  • ‘After Hours’ = Weekdays 330p-7a, 24/7 Weekends & Holidays.
    • ED Attending to call Radiology Attending (x43651) to:
      • Confirm timeframe for ability to interpret study, &
      • Allow for alternate clinical planning (use alternate test, wait for delayed or daytime interpretation, pursue admission, etc.) as deemed appropriate.
    • ED orders ‘CT Cardiac and CTA Coronary (aka CCTA)’ or ‘CTA Chest Triple Rule Out’, if still part of the clinical plan after above Attending-to-Attending discussion.
  • ED to orders ‘Coronary CTA Study Medications (ED)’, if proceeding with CCTA, in order to provide RN with protocol medications.

Indications:

All indications should be met to utilize CCTA from the ED.

  • ED patients with an acute chest pain syndrome and low to intermediate likelihood of coronary artery disease for whom the Risk Calculator recommends CCTA (Class 1a indication).
  • ED patients with Initial troponin normal or equivocal (less than or equal to 0.2ng/ml with a plausible non-coronary cause for elevated troponin; Class 2a indication).
  • ED patients with normal or nondiagnostic ECG for ischemia (Class 1a indication).

 

Contraindications:

The presence of 1 or more contraindications excludes CCTA use from the ED.

  • ED patients for whom the Risk Calculator recommends Admission.
    • ED patients with Heart Score > 6 (High Risk).
    • ED patients with Grace 2.0 > 6% risk for in-hospital event.
  • ED patients for whom the Risk Calculator does NOT recommend CCTA as a testing option.
    • ED patients with >50% risk of obstructive CAD >50%.
    • ED patients with iodine contrast allergy.
  • ED patient already intended for admission to the hospital for any other reason.
  • ED patients with:
    • Known history of obstructive coronary artery disease.
    • CCTA within last 2 years, regardless of findings (if adequate diagnostic study).
    • Current Atrial Fibrillation.
    • Heart Failure with LVEF<30%.
      • LVEF<30% may be considered for CCTA without need for heart rate control with beta-blockers; Nitroglycerin is not contraindicated in these patients.
    • 2nd or 3rd degree AV block.
    • BMI >45 kg/m2.

Workflow:

  • Goal – Heart rate (HR) ≤65 bpm and systolic blood pressure (SBP) ≥90 mmHg at time of scanning.

ED nurse to Assess patient for the following prior to calling CT.

  • 12 lead ECG assess HR and rhythm, BP for baseline hemodynamics.
  • Continue telemetry per ED ACS protocol.
  • Confirm that ED MD has ordered CCTA Study Medications prescribing oral Metoprolol or other beta-blocker of choice with aim to decrease heart rate to target.
  • Metoprolol contraindications -> Alert ED
  • Place on telemetry per ED ACS protocol.
  • 20 gauge or larger IV preferably in right antecubital vein; confirm patency (note that CCTA contrast is rapid at 5-6ml/sec).

ED RN Prep and Care Coordination

  • Confirm ED MD has ordered CCTA & CCTA Study Medications.
  • Decrease patient stimulation to slow heart rate.
  • ED MD prescribes order for nitroglycerin paste 1-inch and conditional order for IV Metoprolol from the Order set “Coronary CTA Study Medications (ED)”.
    • Nitroglycerin ointment to be placed at least 30 min and optimally 60 min prior to test.
      • If pressure declines with nitroglycerin (primarily a venodilator), consider IV fluids and/or MD review.
    • If oral beta blocker given, assess effect on heart rate at >30 min after administration.
      • May administer IV beta blocker on top of oral to achieve heart rate goal.
    • If IV Metoprolol needed, give immediately prior to the imaging: Metoprolol 5mg IV Q5 min, max of 30mg for goal of HR ≤65 and SBP ≥90 mmHg. Vital signs before each additional dose and at least Q15 minutes while administering. –> Transport should be available once IV access established for immediate transfer when HR goal attained or after maximum IV dose administered.
  • CT will call ED RN to coordinate best time for test.
  • Call CT when HR within parameters or maximized IV metoprolol dose, and anticipate immediate transfer to CT.
  • Transport:
    • From 12am-6am ED RN or ED Staff – transport patient to CT to assist with slide transfer; From 6am to 11:59pm – CT staff can pick up the patient.
    • Patient should be a slide transfer, do not have them stand, sit, or walk (to keep HR low).
    • ED RN should be immediately available by phone for assistance PRN.
    • CT technologist takes patient back to ED -patient can scoot over from CT table to stretcher.
  • Post scanning assessment:
    • Nitro paste should be discontinued unless clinically indicated.
    • Take vital signs ~15 and ~30 min post scanning, then per ED routine process.

 

Image interpretation and reporting:

  • Weekday hours.
    • HMC ED:
      • CTA will have a final report (or preliminary impression) by radiology attending ASAP. Since these are urgent cases on stable patients, priority for reading will be given to emergent studies (ex: trauma, stroke, dissection).
      • From 7am to 9 pm (study completion time 6pm), HMC Emergency Radiology Service.
      • From 9pm-7am (from study completion time 8pm to study completion time 6am), UW Overnight Emergency Radiology Service.
    • Montlake ED:
      • From 8am to 5 pm (completion time), Cardiothoracic Radiology Service. From 7am-8am and from 5pm-6pm, preliminary read by cardiothoracic fellow.
      • From 9pm-7am (from study completion time 8pm to study completion time 6am), UW Overnight Emergency Radiology Service.

 

  • Weekends and holidays.
    • CTA will have a final report (or preliminary impression) by radiology attending ASAP. Since these are urgent cases on stable patients, priority for reading will be given to emergent studies (ex: trauma, stroke, dissection). A targeted report will be provided and a CADRADs category will be identified.
    • HMC ED:
      • From 7am to 9 pm (study completion time 8pm), HMC Emergency Radiology Service.
      • From 9pm-7am (from study completion time 8am to study completion time 6am), UW Overnight Emergency Radiology Service.
    • Montlake ED:
      • From 7am to 9pm (study completion time 8pm), HMC Emergency Radiology Service.
      • From 9pm-7am (from study completion time 8pm to study completion time 6am), UW Overnight Emergency Radiology Service.

 

Reporting Template and next steps (simplified):

Reporting will be targeted follow coronary CTA CAD-RADs system, and study will be assigned one of the following categories:

  • CAD-RADS 0: acute coronary syndrome highly unlikely
    • 0% maximal coronary stenosis
  • CAD-RADS 1: acute coronary syndrome highly unlikely
    • 1-24% maximal coronary stenosis, or
    • plaque with no stenosis (positive remodeling)
  • CAD-RADS 2: acute coronary syndrome unlikely
    • 25-49% maximal coronary stenosis
  • CAD-RADS 3: acute coronary syndrome possible
    • 50-69% maximal coronary stenosis
  • CAD-RADS 4: acute coronary syndrome likely
    • CAD-RADS 4A: 70-99% maximal coronary stenosis
    • CAD-RADS 4B: left main >50% stenosis or three-vessel obstructive (≥70% stenosis) disease
  • CAD-RADS 5: acute coronary syndrome very likely
    • 100% maximal coronary stenosis = total occlusion
  • CAD-RADS N: acute coronary syndrome cannot be excluded
    • nondiagnostic study

 

NEXT STEPS:

  • CAD-RADS 0, 1 and 2 next steps: ED discharge if no other concerns. Patient to be followed with outpatient cardiology or primary care physician appointment.
  • CAD-RADS 3, 4, 5 and N next steps: Consider admission to the hospital with cardiology consultation.

 

 

Prepared by UW Coronary CTA ED Taskforce (members listed below):

  • Karen Ordovas (HMC/Montlake Cardiothoracic Radiology)
  • Matthew Cham (HMC/Montlake Cardiothoracic Radiology)
  • Kelley Branch (HMC/Montlake Cardiology)
  • Kevin O’Brien (HMC/Montlake Cardiology)
  • Gulnoor Sheriff (Montlake Technologist)
  • Brian McKinney (Montlake Technologist)
  • Melinda Furrer (Montlake Radiology nursing)
  • Jean Anderson (Montlake ED nursing)
  • Martin Makela (Montlake Emergency Medicine)
  • Jon Medverd (HMC Emergency Radiology)
  • Joel Gross (HMC Emergency Radiology)
  • Jeffrey Robinson (HMC Emergency Radiology)
  • Ken Linnau (HCM Emergency Radiology)
  • Jeff Chun (HMC nursing)
  • Erica Crane (Montlake Technologist)
  • Alexis Rowe (HMC Radiology Nursing)
  • Kimberly Collette (HMC Technologist)
  • Medley Gatewood (HMC Emergency Medicine)
  • Steven Mitchell (HMC Emergency Medicine)

February 2024