Chest Pain: Anatomic vs. Functional Evaluation

Chest Pain: Anatomic vs. Functional Evaluation

Subhi J. Al'Aref, MD
Assistant Professor of Medicine – Division of Cardiology
Director of Cardiac CT
University of Arkansas for Medical Sciences (UAMS)


One of the most common reasons that individuals seek medical care is the occurrence of chest pain. In fact, chest pain is responsible for more than 6.5 million visits to the emergency room in the United States, which is approximately 4.7% of all emergency room visits. Chest pain also accounts for more than four million outpatient visits annually across the United States. While pain originating from the chest area can be attributed to multiple underlying conditions, the typical approach usually entails exclusion of significant underlying coronary artery disease, since the presence of progressive chest pain can be the hallmark of impending myocardial infarction. As such, it is imperative to establish an accurate diagnosis in a timely manner for the institution of appropriate therapies.

The traditional approach for the noninvasive evaluation of chest pain entails the use of stress testing. During a stress test, the goal is to elicit myocardial ischemia when oxygen demand exceeds oxygen supply in individuals with underlying significant coronary artery disease (which is known as the functional approach). With the advent of coronary computed tomography angiography (coronary CTA), it is possible to accurately and noninvasively image the coronary arteries and directly evaluate for the presence of atherosclerotic plaque, atherosclerotic plaque burden and distribution in patients with chest pain (this approach is termed the anatomical approach). The reason behind the need for a more contemporary approach is the low diagnostic yield of the functional approach. For example, a large analysis from the National Cardiovascular Data Registry found that approximately two-thirds of patients who undergo an invasive coronary angiogram after a positive stress test are not found to have obstructive coronary artery disease. Furthermore, the presence of myocardial ischemia indicates the presence of obstructive atherosclerosis, and not all plaque rupture (i.e. plaque that leads to a myocardial infarction) is obstructive before it ruptures. In a study of patients undergoing serial invasive coronary angiograms before a myocardial infarction, 68% of plaque that led to a myocardial infarct was nonobstructive at baseline. Thus, functional evaluation is not only inaccurate at diagnosing obstructive coronary artery disease, it also does not answer the main clinical question which related to plaque morphology and stability (as the main goal is to prevent the occurrence of a myocardial infarction). 

Coronary CTA has been validated against invasive coronary angiography as an accurate noninvasive imaging modality for the detection of obstructive coronary artery disease. It can also be used to directly assess plaque morphology and stability. Furthermore, the findings on coronary CTA have been shown to accurately prognosticate clinical outcomes in individuals with coronary artery disease. While the PROMISE trial did not show a difference in outcomes between anatomic and functional evaluation, the large multicenter randomized SCOT-HEART trial showed that the use of coronary CTA in addition to standard care in patients with stable chest pain resulted in a significantly lower rate of death from coronary heart disease or nonfatal myocardial infarction at 5 years than standard care alone. Coronary CTA has also been validated in higher risk groups as shown in the VERDICT and DISCHARGE trials. As such, the 2021 ACC/AHA chest pain guidelines have recommended coronary CTA as a class I indication for workup of chest pain.


In conclusion:

  1. Coronary CTA is a class I indication for workup of chest pain.
  2. Coronary CTA accurately discriminates between non-obstructive and obstructive CAD and is an effective gatekeeper for invasive coronary evaluation.
  3. Coronary evaluation using CTA can alter short- and long-term outcomes through institution of patient-appropriate and disease-specific therapies.



  1. Patel MR, Peterson ED, Dai D, Brennan JM, Redberg RF, Anderson HV, Brindis RG, Douglas PS. Low diagnostic yield of elective coronary angiography. N Engl J Med. 2010;362: 886-95.
  2. Writing Committee Members, Gulati M, Levy PD, Mukherjee D, Amsterdam E, Bhatt DL, Birtcher KK, Blankstein R, Boyd J, Bullock-Palmer RP, Conejo T, Diercks DB, Gentile F, Greenwood JP, Hess EP, Hollenberg SM, Jaber WA, Jneid H, Joglar JA, Morrow DA, O'Connor RE, Ross MA, Shaw LJ. 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. J Am Coll Cardiol. 2021;78: e187-e285.
  3. SCOT-HEART Investigators, Newby DE, Adamson PD, Berry C, Boon NA, Dweck MR, Flather M, Forbes J, Hunter A, Lewis S, MacLean S, Mills NL, Norrie J, Roditi G, Shah ASV, Timmis AD, van Beek EJR, Williams MC. Coronary CT Angiography and 5-Year Risk of Myocardial Infarction. N Engl J Med. 2018;379: 924-933.
  4. Douglas PS, Hoffmann U, Patel MR, Mark DB, Al-Khalidi HR, Cavanaugh B, Cole J, Dolor RJ, Fordyce CB, Huang M, Khan MA, Kosinski AS, Krucoff MW, Malhotra V, Picard MH, Udelson JE, Velazquez EJ, Yow E, Cooper LS, Lee KL; PROMISE Investigators. Outcomes of anatomical versus functional testing for coronary artery disease. N Engl J Med. 2015;372: 1291-300.
  5. Falk E, Shah PK, Fuster V. Coronary plaque disruption. Circulation . 1995;92: 657-71.