Chest pain is the second most common reason people come to the emergency department (ED) (behind stomach and abdominal complaints), accounting for more than 7 million ED visits in the United States each year according to the latest data from the National Hospital Ambulatory Medical Care Survey.1
Getting to the bottom of what's causing chest pain is crucial when it comes to delivering the appropriate coronary artery disease treatment. But there's a challenge: more than half of those chest pain cases will have a noncardiac cause, and only about one in twenty will be traced to an acute coronary syndrome.2
When patients present with either acute or chronic chest pain, cardiologists—concerned about missing significant coronary disease—may opt to skip basic diagnostic tests and go straight to advanced imaging or invasive angiography. The result may be a cascade of unnecessary testing and treatment, including stenting, which could drive up coronary artery disease treatment costs. Indeed, the authors of new chest pain guidelines from the American Heart Association, the American College of Cardiology, and society partners state, "Reducing unnecessary testing can provide a means to exert cost savings within the diagnostic evaluation of populations."3
Choosing a Test
It could be that no testing is required in patients with low risk of CAD, but if the likelihood of coronary disease is intermediate to high, physicians must further consider the specifics of each patient. In the chest pain guidelines, coronary CT angiography (CCTA) is preferred for the evaluation of a patient who is younger than sixty-five and is suspected of having less obstructive CAD, whereas a stress test is favored in an older patient likely to have more obstructive disease.
Exercise ECG is the first recommendation in the guideline section on diagnostic testing, with the authors noting that it is "the lowest cost procedure used in the diagnostic evaluation when compared with stress imaging or anatomic procedures, with the exception of coronary artery calcium (CAC) scoring." Candidates for exercise ECG include patients without disabling comorbidities who are able to perform everyday activities and exercise and who don't have ST-T abnormalities on ECG at rest.
The guidelines additionally review scenarios in which a physician might consider escalating to use of CCTA, stress echocardiography, stress nuclear myocardial perfusion imaging, and stress CMR, including a table of contraindications to exercise ECG and these other diagnostic modalities.
Keeping an Eye on Coronary Artery Disease Treatment Cost
Testing for suspected CAD consumes a lot of healthcare resources, and the new chest pain guideline discusses the balance between cost and value when considering various available tests: "Cost should . . . be considered, when known by the ordering clinician and there is equipoise between available modalities." Importantly, the authors say, urgent diagnostic testing isn't warranted for low-risk patients, with patients with at least intermediate risk of obstructive CAD having the most to gain from cardiac testing and imaging.
The value, or cost-effectiveness, of various testing modalities has been studied extensively, providing some guidance for cardiologists considering options for their patients. For instance, an analysis of the PROMISE trial, which showed no difference in clinical outcomes between stable symptomatic patients with suspected CAD initially evaluated with CCTA versus functional testing, demonstrated that initial costs were lowest when exercise ECG was chosen as the first test ($174) and highest when pharmacologic stress nuclear testing was selected ($1,132).4 Costs were slightly higher with the CCTA strategy than with functional testing at ninety days as a result of more revascularizations and catheterizations, although average cost differences out to three years were small.
Cardiologists have a lot of options to choose from when evaluating a patient with suspected CAD. The inexpensive and widely available ECG is often one of the first they'll go to, as it's been shown to be useful both for diagnosis and for risk stratification in patients with coronary disease.
The Benefits of Starting with ECG Testing
There's some evidence that starting with exercise ECG and then escalating to more expensive modalities as needed is the way to go. "The economic evidence for the exercise ECG supports that tiered testing may offset its reduced diagnostic accuracy," the authors of the chest pain guideline note. Additional studies support the idea of starting with an exercise ECG:
- One analysis indicated that using exercise ECG first, followed by selective stress echocardiography, both improved diagnostic accuracy and resulted in better cost-effectiveness compared with other approaches.5
- Another found that the most cost-effective strategy started with exercise ECG, followed by selective stress CMR and invasive angiography.6
- Yet another study of patients with stable chest pain and suspected CAD supported the cost-effectiveness of a tiered strategy starting with exercise treadmill testing and using imaging only if the result was ambiguous or if the test couldn't be performed.7
This research positions exercise ECG as a way to limit the use of more expensive diagnostic modalities as much as possible, potentially saving the healthcare system and patients money without compromising patient care.
Authors of a state-of-the-art review in the Journal of the American College of Cardiology8 argue that exercise stress ECG is underused in the era of advanced imaging modalities, stating that information from the test "can yield substantial data for risk stratification, either supplementary to imaging variables or without concurrent imaging." On the other hand, advanced imaging has greater diagnostic and prognostic value in higher-risk patients. Ultimately, the authors say, "optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness."
References:
1. Centers for Disease Control and Prevention. NAMCS/NHAMCS – Ambulatory Health Care Data Homepage. https://www.cdc.gov/nchs/ahcd/index.htm. Accessed November 18, 2021.
2. Hsia RY, Hale Z, Tabas JA. A national study of the prevalence of life-threatening diagnoses in patients with chest pain. JAMA Internal Medicine. July 2016;176(7):1029-1032. https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2527387
3. Gulati M, Levy PD, Mukherjee D, et al. 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. Journal of the American College of Cardiology. October 2021. https://www.jacc.org/doi/10.1016/j.jacc.2021.07.053
4. Mark DB, Federspiel JJ, Cowper PA, et al. Economic outcomes with anatomical versus functional diagnostic testing for coronary artery disease. Annals of Internal Medicine. July 2016;165(2):94-102. https://www.acpjournals.org/doi/full/10.7326/M15-2639
5. Genders TSS, Petersen SE, Pugliese F, et al. The optimal imaging strategy for patients with stable chest pain: a cost-effectiveness analysis. April 2015;162(7):474-484. https://www.acpjournals.org/doi/10.7326/M14-0027
6. Walker S, Girardin F, McKenna C, et al. Cost-effectiveness of cardiovascular magnetic resonance in the diagnosis of coronary heart disease: an economic evaluation using data from the CE-MARC study. Heart. May 2013;99:873-881. https://heart.bmj.com/content/99/12/873
7. Min JK, Gilmore A, Jones EC, et al. Cost-effectiveness of diagnostic evaluation strategies for individuals with stable chest pain syndrome and suspected coronary artery disease." Clinical Imaging. May 2017;43:97-105. https://www.clinicalimaging.org/article/S0899-7071(17)30015-3/fulltext
8. Bourque JM and Beller GA. Value of exercise ECG for risk stratification in suspected or known CAD in the era of advanced imaging technologies.
JACC: Cardiovascular Imaging. November 2015;8(11):1309-1321. https://www.jacc.org/doi/abs/10.1016/j.jcmg.2015.09.006