Multicenter Study to Rule Out Myocardial Infarction by Cardiac Computed Tomography
Condition: Acute Coronary Syndrome; Myocardial Infarction; Unstable Angina Pectoris
MeSH terms: Myocardial Infarction; Acute Coronary Syndrome; Angina Pectoris; Angina, Unstable; Infarction
Study type: Interventional
Phase: Phase 3

Summary: 
      The growing availability of cardiac computed tomography (CT)* in emergency departments (EDs)
      across the U.S. expands the opportunities for its clinical application, but also heightens
      the need to define its appropriate use in the evaluation of patients with acute chest pain.
      To address this need, we performed a randomized diagnostic trial (RDT) to determine whether
      integrating cardiac CT, along with the information it provides on coronary artery disease
      (CAD) and left ventricular (LV) function, can improve the efficiency of the management of
      these patients (i.e. shorten length of hospital stay, increase direct discharge rates from
      the ED, decreasing healthcare costs and improving cost effectiveness while being safe).
    

Detailed description: 
      Patients with acute chest pain and normal or non-diagnostic electrocardiograms (ECGs)
      represent a cohort whose management is notably inefficient and diagnostically challenging.
      Because in less than 30% of EDs diagnostic testing (e.g. nuclear imaging, echocardiography,
      and exercise treadmill ECG) that would allow physicians to rule out the occurrence of
      myocardial ischemia is performed as part of the initial evaluation, most of these patients
      are hospitalized for 24 to 36 hours to exclude the presence of acute coronary syndrome (ACS).
      Of the six million acute chest pain patients admitted each year in the U.S. under these
      conditions, less than 10% of them ultimately receive a diagnosis of ACS at discharge.
      Moreover, inpatient care for negative evaluations imparts an economic burden in excess of $8
      billion annually.

      Since acute myocardial ischemia and necrosis are rare in the absence of coronary artery
      disease, a technology that reliably identifies CAD may allow physicians to discharge chest
      pain patients directly from the ED. Cardiac CT is a safe, high-speed, noninvasive imaging
      technique that accurately detects coronary atherosclerotic plaque and stenosis, and also
      allows physicians to assess global and regional LV function.

      Observational studies have demonstrated that approximately 40% of acute chest pain patients
      have no evidence of atherosclerosis on cardiac CT, and that an additional 30% have no
      evidence of hemodynamically significant (>50%) coronary artery stenosis. Both of these
      criteria are powerful predictors of the absence of both ACS and major adverse cardiovascular
      events (negative predictive value [NPV] of 98%). The specificity of cardiac CT is further
      increased when global and regional LV function is normal. Several studies have demonstrated
      that cardiac CT, with its high NPV, can be effectively used to rule out ACS, but little is
      known about the willingness ability of ED physicians to use this information to augment
      patient management.

      We therefore performed a trial at 9 clinical sites and randomized 1000 patients with acute
      chest pain and normal or non-diagnostic ECGs, to receive either standard ED evaluation (no
      intervention) or a cardiac CT (experimental) in the evaluation of acute chest pain in the
      emergency room. (Rule Out Myocardial Infarction using Computer Assisted Computed Tomography
      [ROMICAT II]).
    

Intervention name(s): Cardiac Computed Tomography
Intervention type(s): Radiation
Intervention description(s): A contrast enhanced cardiac CT was performed in addition to standard evaluation. Reconstructed data sets were evaluated for the presence of coronary artery calcium, coronary atherosclerotic plaque and stenosis, LV function and incidental findings.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: acute chest pain; emergency department; cardiac computed tomography