Chest Pain Assessment Reimagined: When to Use Coronary CT vs. Stress Testing

A practical guide for primary care on risk stratification, imaging selection, and referral decisions.

Author: Norton Healthcare

Published: December 18, 2025

Chest pain is one of the most common presenting complaints in primary care, yet determining which patients need specialist referral versus reassurance remains challenging. Recent guidelines have fundamentally changed the approach to these patients, and understanding the current evidence can help primary care physicians make more informed decisions about testing and referral.

The initial step in evaluating any patient with chest pain is risk stratification. While multiple models exist, including the classic Diamond-Forrester model, most incorporate:

  • Type of chest pain (nonanginal, atypical or typical)
  • Age (a major driver of risk)
  • Cardiovascular risk factors (family history, smoking, inflammatory disease, dyslipidemia, hypertension, diabetes)

The quality of pain matters significantly. Central pressure, squeezing or heaviness is a red flag for ischemia and urgent evaluation. Sharp, fleeting or pleuritic pain is less likely to be cardiac in origin.

The paradigm shift: Anatomic vs. functional testing

For decades, functional stress testing was the primary tool. Now, there are two distinct pathways: functional testing (traditional stress tests) and anatomic imaging (coronary CT angiography). Understanding when to use each is crucial.

Functional testing options

Exercise treadmill stress testing remains useful for lower-risk patients. It’s low-cost, highly available, provides prognostic data and doesn’t expose patients to radiation. However, sensitivity and specificity hover around 70%, dropping to approximately 50% in women. It’s less accurate in patients with known coronary disease, in those with baseline electrocardiogram (EKG) changes or those unable to exercise.

Stress echocardiography improves sensitivity and specificity to around 80% without radiation exposure. However, it’s technically difficult and not recommended for patients with poor echocardiographic windows (chronic obstructive pulmonary disease, breast implants, obesity) or paced rhythm.

Nuclear SPECT imaging has been the workhorse for years, offering improved sensitivity over treadmill testing. It works well for patients with known coronary disease, prior bypass or stents. The main limitation is that multivessel disease can lead to false negatives due to balanced ischemia. It does expose patients to radiation.

PET imaging offers improved sensitivity and specificity over SPECT, particularly for patients with body mass index (BMI) over 40 or previous false-positive SPECT tests. However, availability is limited, costs are higher and insurance approval can be challenging.

The rise of coronary CT angiography- anatomicimaging

Two landmark trials — PROMISE (2015) and SCOT-HEART— fundamentally changed our approach to chest pain evaluation. The SCOT-HEART trial demonstrated that patients receiving coronary CT had significantly lower risk of death from myocardial infarction on long-term follow-up, likely because more patients received aggressive lipid-lowering therapy, aspirin and antianginals based on CT findings.

Based on this evidence, the 2021 chest pain guidelines now give coronary CT angiography a Class 1A recommendation for intermediate to high-risk patients, compared to a 1B recommendation for functional testing. This is a significant endorsement of anatomic imaging.

Advantages of coronary CT

Coronary CT offers several compelling benefits:

  • Anatomic assessment detecting both symptomatic and presymptomatic disease
  • Superior negative predictive value — a normal coronary CT provides a “warranty period” of at least two years versus one year for stress testing
  • Higher sensitivity, particularly in women
  • Ability to identify multivessel disease without the balanced ischemia problem
  • Plaque quantification and characterization

“The diagnostic power of coronary CT has transformed how we approach chest pain,” said Arpit Agrawal, M.D., a cardiologist specializing in cardiac imaging with Norton Heart & Vascular Institute. “We’re not just identifying obstructive disease anymore — we’re catching presymptomatic atherosclerosis that allows us to intervene earlier with aggressive medical therapy. This is where we see the real mortality benefit.”

Dr. Agrawal presented “Evaluation of Chest Pain: Outpatient Assessment” at the 2025 Norton Heart & Vascular Institute Symposium continuing medical education opportunity.

When not to use coronary CT

Despite its advantages, coronary CT isn’t appropriate for all patients:

  • IV contrast allergies or significant renal dysfunction (generally GFR less than 45)
  • Frequent arrhythmias (PVCs, PACs, atrial fibrillation, significant sinus arrhythmia)
  • Previous coronary interventions (stents or bypass grafts — current technology can’t adequately image through stents)
  • BMI greater than 40 (be cautious even above 35 due to decreased diagnostic accuracy)
  • Previously elevated coronary calcium scores (some institutions use greater than 1,000 as a cutoff)
  • Inability to tolerate exam protocols (breath-holding, nitroglycerin, beta blockade, heart rate control to ~60 bpm)

For these patients, functional stress testing remains the better option.

The role of CT-FFR

For patients with intermediate stenosis (40% to 90%) on coronary CT, CT fractional flow reserve (CT-FFR) has become a game-changer. This technology uses computational fluid dynamics to simulate invasive FFR without additional testing, helping determine which lesions are functionally significant.

CT-FFR dramatically improves diagnostic performance (area under the curve 0.94 versus 0.83 for CT alone or 0.7 for SPECT) and changes management in approximately two-thirds of patients with intermediate stenosis. Perhaps most impressively, the FISH & CHIPS trial (2023) showed an 8% relative reduction in all-cause mortality and 14% relative reduction in cardiovascular mortality at two years in institutions with CT-FFR availability.

Using CT-FFR, the percentage of patients going to invasive angiography who actually need intervention jumps from 30% to 75%, significantly reducing unnecessary catheterizations.

Current recommendations by risk category

Low-risk patients: No testing is recommended (Class 1 recommendation), though exercise stress EKG or coronary calcium scoring can be considered if testing is deemed necessary.

Intermediate to high-risk patients: Coronary CT angiography is preferred, particularly for patients generally under age 65 with lower likelihood of obstructive disease. Stress testing remains preferred for those at higher risk or with contraindications to CT.

When stress testing still has a role

Despite the advantages of coronary CT, functional stress testing remains important for:

  • Older patients with very high probability of coronary disease
  • Patients with known coronary disease, stents or bypass grafts
  • Unstable heart rate or significant arrhythmias
  • Renal dysfunction or contrast allergy
  • Need for functional capacity assessment
  • BMI greater than 40

The future of chest pain evaluation

Several exciting developments are on the horizon:

Exercise PET imaging will become more available with the recent Food and Drug Administration approval of flurpiridaz, a new radiotracer that allows exercise PET stress testing, potentially driving down costs and increasing utilization.

Artificial intelligence-driven plaque analysis is revolutionizing coronary CT interpretation. Unlike calcium scoring, which captures only one type of plaque, CT can quantify noncalcified plaque, lipid-rich plaque and pericoronary fat — all markers of future cardiovascular events. Plaque analysis changes management in approximately 50% of patients, with a third of patients who have zero calcium scores receiving management changes based on comprehensive plaque assessment.

Photon-counting CT scanners eventually will allow adequate imaging through stents and bypass grafts, potentially expanding the population that can benefit from anatomic assessment.

Bottom line for primary care

Coronary CT angiography is now the only Class 1A recommendation for outpatient evaluation of chest pain in patients without known coronary artery disease. European guidelines have gone even further, recommending it as first-line treatment (not just equivalent to stress testing) for these patients.

The key advantage isn’t just diagnosing symptomatic disease — it’s identifying presymptomatic atherosclerosis that allows for aggressive secondary prevention measures, which appears to drive the mortality benefit seen in clinical trials.

However, patient selection matters. Know the contraindications, prepare patients appropriately (heart rate control is crucial), and recognize when functional stress testing remains the better choice.

“We’re moving toward a future where coronary CT functions more like cancer screening — identifying disease before it becomes symptomatic,” Dr. Agrawal said. “For primary care physicians, understanding which patients benefit from anatomic versus functional assessment is key to optimal cardiovascular risk management.”

Practical preparation tips for coronary CT

If you’re ordering coronary CT, ensure:

  • Patient fasts for about four hours before the test
  • Large bore IV access (preferably AC; PICCs not recommended)
  • Oral beta-blockers prescribed for the day before and day of test to achieve heart rate about 60 bpm (oral loading is more effective than IV)
  • In Epic, use the CT angiogram with 3D imaging order set, which includes beta-blocker and ivabradine options.
  • Consider ivabradine for patients with low blood pressure (though it can be expensive).
  • Patient can tolerate nitroglycerin, breath-holding and lying still

When in doubt about the appropriate test or interpretation of results, don’t hesitate to refer to cardiology. Early consultation can help ensure patients receive the most appropriate diagnostic pathway and timely intervention when needed.

Clinical pearls: key takeaways

  • Coronary CT is now 1A for intermediate to high-risk patients without known coronary artery disease — the strongest recommendation in the guidelines. A normal CT clears patients for at least two years versus only one year for stress testing.
  • Exercise treadmill testing has only about 50% sensitivity in women versus 70% to 80% in men. Consider coronary CT or imaging-based stress tests for better accuracy.
  • Heart rate control is critical for CT success: Load patients with oral metoprolol the day before and day of the test — oral loading works better than IV for steady control.
  • Don’t CT patients with stents, bypass grafts, significant arrhythmias, BMI greater than 40 or GFR less than 45. Use functional stress testing instead for these populations.
  • CT-FFR is a game-changer: It increases catheterization yield from 30% to 75% and has been associated with 8% reduction in all-cause mortality at two years.
  • The mortality benefit comes from catching presymptomatic disease: Early plaque detection allows aggressive medical therapy before events occur — this is where CT outperforms stress testing.