October 29, 2021 — A new guideline for the evaluation and diagnosis of chest pain was released this week that provides recommendations and algorithms for clinicians to assess and diagnose chest pain in adult patients. It is a multi-society guideline and represents the first-ever U.S. or international guideline for the evaluation and diagnosis of patients with acute or stable chest pain.
It was developed by the American College of Cardiology (ACC) and the American Heart Association (AHA), in coordination with the American Society of Echocardiography (ASE), Society of Cardiovascular Computed Tomography (SCCT) Society of Cardiovascular Magnetic Resonance (SCMR), the American College of Chest Physicians (CHEST), and the Society for Academic Emergency Medicine (SAEM).
Chest pain is a frequent cause for emergency department visits in the United States. This guideline presents an evidence-based approach to risk stratification and the diagnostic workup for the evaluation of chest pain. Cost-value considerations in diagnostic testing have been incorporated, and shared decision-making with patients is recommended.
To create the recommendations, a comprehensive literature search was conducted from November 2017 to May 2020, encompassing randomized and nonrandomized trials, observational studies, registries, reviews and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases. Additional relevant studies, published through April 2021, were also considered.
The guideline includes sections on:
• Physical examination.
• Diagnostic Testing, including ECG, chest radiography and biomarkers
• Anatomical testing using coronary computed tomography angiography (CCTA), and invasive coronary angiography.
• Diagnostic Testing, including use of exercise ECG, echocardiography/stress echo, stress nuclear (PET or SPECT) myocardial perfusion imaging, and cardiac MRI (CMR).
• Cardiac testing considerations for women who are pregnant, postpartum, or of child-bearing age.
• Choosing the right pathway with patient-centric algorithms for acute chest pain.
• Evaluation of acute chest pain with nonischemic cardiac pathologies, including pulmonary embolism (PE), acute aortic syndrome, suspected myopericarditis, and valvular heart disease.
• Evaluation of Patients With Stable Chest Pain, including with no known CAD, and with known CAD.
• Cost-value considerations in diagnostic testing, including CCTA and calcium scoring scans, exercise ECG, stress echo, stress nuclear and CRM.
Top 10 Take-Home Messages for the Evaluation and Diagnosis of Chest Pain
The following takeaways were provided in the the guideline document:
1. Chest Pain Means More Than Pain in the Chest. Pain, pressure, tightness, or discomfort in the chest, shoulders, arms, neck, back, upper abdomen, or jaw, as well as shortness of breath and fatigue should all be considered anginal equivalents.
2. High-Sensitivity Troponins Preferred. High-sensitivity cardiac troponins are the preferred standard for establishing a biomarker diagnosis of acute myocardial infarction, allowing for more accurate detection and exclusion of myocardial injury.
3. Early Care for Acute Symptoms. Patients with acute chest pain or chest pain equivalent symptoms should seek medical care immediately by calling 9-1-1. Although most patients will not have a cardiac cause, the evaluation of all patients should focus on the early identification or exclusion of life-threatening causes.
4. Share the Decision-Making. Clinically stable patients presenting with chest pain should be included in decision-making; information about risk of adverse events, radiation exposure, costs, and alternative options should be provided to facilitate the discussion.
5. Testing Not Needed Routinely for Low-Risk Patients. For patients with acute or stable chest pain determined to be low risk, urgent diagnostic testing for suspected coronary artery disease is not needed.
6. Clinical decision pathways for chest pain in the emergency department and outpatient settings should be used routinely.
7. Accompanying Symptoms. Chest pain is the dominant and most frequent symptom for both men and women ultimately diagnosed with acute coronary syndrome. Women may be more likely to present with accompanying symptoms such as nausea and shortness of breath.
8. Identify Patients Most Likely to Benefit From Further Testing. Patients with acute or stable chest pain who are at intermediate risk or intermediate to high pre-test risk of obstructive coronary artery disease, respectively, will benefit the most from cardiac imaging and testing.
9. Noncardiac Is In, Atypical Is Out. “Noncardiac” should be used if heart disease is not suspected. “Atypical” is a misleading descriptor of chest pain, and its use is discouraged.
10. Structured Risk Assessment Should Be Used. For patients presenting with acute or stable chest pain, risk for coronary artery disease and adverse events should be estimated using evidence-based diagnostic protocols.
Table 1 in the guidelines explain how to apply ACC/AHA class of recommendation and level of evidence to clinical strategies, interventions, treatments or diagnostic testing.
Cardiac CT Given Strong Recommendation as Front-line Imaging of Chest Pain
The Society of Cardiovascular Computed Tomography sent out a notice to members on the new guidelines, noting the prominent recommendation for CCTA and impact this may have on cardiac CT.
The new chest pain guideline recommends CCTA as a frontline testing strategy in the evaluation of patients with stable and acute chest pain who have no known coronary artery disease (CAD). It was given a Class 1 recommendation and level of evidence of A.
Class 1 is the strongest recommendation available for a medical test. Level A indicates there is high-quality evidence from more than one randomized clinical trial (RCT) that CCTA is beneficial, useful and effective.
The guideline also provides a Class 1 recommendation for stress testing for both groups of patients, including either exercise ECG, stress echocardiography, stress positron emission tomography (PET)/single photon emission computed tomography (SPECT), myocardial perfusion imaging (MPI) or stress CMR. The guideline labels the evidence supporting the use of these tests in cases of acute chest pain as B-NR, or “moderate-quality evidence … from non-randomized studies” and for patients with stable chest pain as B-R, or “moderate-quality evidence from 1 or more RCTs.”
Fractional-flow reserve CT (FFR-CT) was also given a high endorsement, with a level of evidence of 2A in four categories of patients with chest pain and appeared prominently in multiple flow charts.
FFR-CT enables a noninvasive way to evaluate coronary disease so a patient does not need to be sent to the cath lab for an invasive angiogram or invasive catheter FFR measurement. It offers FFR measurements for the entire coronary tree, rather than the catheter-based method of one vessel at a time. FFR also shows if a lesion needs to be revascularized or if it can be treated with medication. CT can be used to help rule our coronary involvement, but the addition of this technology is considered definitive in ruling out coronary causes of chest pain.
ASNC Did Not Endorse The Guidelines on Chest Pain Evaluation
The American Society of Nuclear Cardiology (ASNC) sent a letter to its members this week stating it did not endorse the guideline. After much deliberation, ASNC’s Board of Directors said that the society could not endorse the guideline because the majority of board members were of the opinion that important parts of the document do not support the principle of patient first imaging and they did not support the strong endorsement for FFR-CT.
"We believe that the document fails to provide unbiased guidance to healthcare professionals on the optimal evaluation of patients with chest pain," the board said in a statement to members.
They cited the lack of balance in the document’s presentation of the science on FFR-CT and what the board felt was an inappropriately prominent endorsement. The board members said they had a major concern over what they described as an oversized role given to FFR-CT. They said there is limited availability of this technology and most centers, and there is limited information on efficacy, a sizable cost to use the technology, and inconsistent insurance coverage.
Many CCTA experts have said FFR-CT offers the ability to see if there is ischemia in the heart and pinpoint the location of a blockage. SPECT and PET also can determine if there is ischemia, but the imaging cannot specify the exact area of the culprit lesion in a vessel segment. While nuclear imaging remains the gold-standard for myocardial perfusion imaging, CT is more widely available and some experts have advocated for a CT-first approach for chest pain patients.
No one test is perfect for all patients, and he decision about which test to order can be a nuanced one and cardiac imaging tests tend to be complementary, the ASNC Board wrote in an editorial. They said careful patient selection is needed and physician and technical local expertise, availability, quality of equipment, and patient preference are extremely important factors to consider.
"There is not enough emphasis on this important point, and it is hard to capture this concept in flow charts," the board stated. "This is an important limitation of the guideline."