In a patient with a 2 cm ground‑glass opacity in the left upper lobe, multiple nodules in the right lower lobe, mild‑to‑moderate emphysema, atherosclerotic disease with a 4 cm ascending‑aortic ectasia, and probable cysts in the left liver lobe and left kidney, who has dyspnea on exertion, should the initial evaluation be a coronary computed tomography angiography (CCTA) or a pharmacologic stress test with imaging?

Proceed with CCTA as the initial test for this patient with dyspnea on exertion

In this patient with known atherosclerotic disease, coronary calcification, and dyspnea on exertion, CCTA is the recommended first-line diagnostic test to rule out obstructive coronary artery disease (CAD), given the moderate pre-test likelihood of disease. 1

Rationale for CCTA Over Stress Testing

Pre-test Likelihood Assessment

This patient has multiple features suggesting moderate pre-test likelihood of obstructive CAD:

• Known atherosclerosis with coronary artery calcification
• Aortic atherosclerotic disease with 4 cm ectasia
• Dyspnea on exertion (though atypical for angina)
• Likely older age given the CT findings

According to the 2024 ESC Guidelines, in patients with moderate (>5%–50%) pre-test likelihood of obstructive CAD, CCTA is recommended as the preferred diagnostic modality to rule out obstructive disease 1. The guidelines specifically state that CCTA is the test of choice for ruling out obstructive CAD in this likelihood range.

Why CCTA is Superior in This Case

1. Anatomical clarity: CCTA will definitively assess the severity of coronary atherosclerosis already evident on the non-contrast CT, providing precise anatomical information about stenosis severity 1

2. High negative predictive value: A normal CCTA effectively rules out obstructive CAD with very low post-test likelihood (approximately 2%), allowing you to confidently pursue alternative explanations for dyspnea 1

3. Sequential testing strategy: If CCTA shows CAD of uncertain functional significance (typically 40-70% stenosis), functional testing can then be performed sequentially to determine hemodynamic significance 1. This approach is more efficient than starting with functional testing, which would still require anatomical assessment if positive.

4. Comprehensive evaluation: CCTA can simultaneously assess the ascending aortic ectasia more precisely and evaluate for other structural abnormalities

When Functional Testing Would Be Preferred

Stress testing (pharmacologic given the pulmonary disease) would be more appropriate if:

• Pre-test likelihood were high (>50-60%), where a positive functional test alone could have sufficient post-test likelihood to guide management 1
• CCTA were contraindicated (severe renal dysfunction, contrast allergy)
• CCTA showed intermediate stenoses requiring functional correlation 1

Critical Caveat: The Pulmonary Findings

The 2 cm ground-glass opacity and multiple nodules require urgent attention and may actually be the primary cause of dyspnea. The recommended 6-month follow-up for a 2 cm GGO is potentially inadequate—this size lesion warrants closer surveillance or tissue diagnosis, particularly given the multiple additional nodules 2, 3. The emphysema itself can cause exertional dyspnea independent of cardiac disease 4.

Practical Algorithm:

1. Obtain CCTA first to definitively rule out obstructive CAD 1
2. If CCTA shows no obstructive disease or only mild non-obstructive plaque, the dyspnea is likely pulmonary in origin
3. If CCTA shows intermediate stenoses (50-70%), proceed to pharmacologic stress imaging (vasodilator stress preferred over dobutamine given emphysema) with SPECT or PET to assess functional significance 1, 5
4. If CCTA shows severe disease (≥70% stenosis in proximal LAD, left main ≥50%, or three-vessel disease), proceed directly to invasive angiography with FFR/iFR capability 1

Do not delay addressing the pulmonary nodules—consider multidisciplinary discussion regarding the GGO management timeline, as malignancy remains a significant concern that may be contributing to symptoms.