Does this patient with rectal cancer and exertional chest pain require immediate follow-up after an inconclusive stress test?

This Patient Requires Follow-Up Testing

This stress test is incomplete and requires follow-up with coronary CT angiography (CCTA) to definitively exclude obstructive coronary artery disease. 1, 2

Why This Test is Inadequate

The stress test failed on multiple technical grounds that prevent any meaningful clinical conclusion:

• Suboptimal heart rate achievement: The patient reached only 87% of maximum predicted heart rate (152 bpm of 174 bpm target), and stress images were obtained at an even lower range of 85-120 bpm (48-68% of age-predicted maximum). 2 Achieving <85% of age-predicted maximal heart rate significantly reduces sensitivity for detecting ischemia and renders the test non-diagnostic. 2

• Poor endocardial definition: This technical limitation completely prevents accurate assessment of regional wall motion abnormalities, making the echocardiographic component non-diagnostic. 2

• Baseline ECG artifact: The stress ECG was uninterpretable at peak exercise due to artifact, further limiting diagnostic value. 1

Guideline-Directed Next Step

The 2021 ACC/AHA Chest Pain Guidelines provide a Class 2a, Level C-EO recommendation for CCTA in patients with inconclusive prior stress testing to exclude atherosclerotic plaque and obstructive CAD. 1, 2

The report itself explicitly states: "Consider an alternative imaging modality for further evaluation." 2

Why CCTA is the Optimal Choice

CCTA offers several advantages over repeating stress testing in this scenario:

• Does not depend on achieving target heart rate, eliminating the limitation that made the initial test inconclusive. 2

• Provides definitive anatomic information with high negative predictive value for excluding obstructive coronary disease. 2

• Avoids repeating the same test modality that already proved technically inadequate. 1

Clinical Context Supporting Follow-Up

This patient has multiple factors warranting definitive evaluation:

• Symptomatic presentation: History of exertional and non-exertional chest pain, though currently resolved. 1

• Cancer diagnosis with planned chemoradiation: Certain cancer therapies increase cardiovascular risk, and baseline cardiac assessment is important. 3

• No known cardiac history: This is a de novo evaluation requiring definitive exclusion or confirmation of coronary disease to guide future management. 1

• Good functional capacity: The patient achieved 11.8 METs with excellent exercise tolerance, suggesting ability to undergo further testing safely. 4

Risk of No Follow-Up

Without definitive testing, this patient faces:

• Uncertain risk for undiagnosed obstructive coronary disease that could lead to acute coronary syndrome. 2

• Inappropriate medical management without knowing true coronary anatomy. 2

• Potential for sudden cardiac death if significant disease is present but undetected. 2

• Inability to risk-stratify before proceeding with cancer treatment that may have cardiovascular toxicity. 3

Common Pitfall to Avoid

Do not simply repeat the same stress test modality. 1 The 2021 guidelines specifically recommend CCTA after an inconclusive stress test to avoid the potential for another inconclusive result and to enable more definitive rule-out of obstructive CAD. 1

Recommended Action Plan

1. Order CCTA as the next diagnostic test to definitively assess for coronary atherosclerosis and obstructive disease. 1, 2

2. If CCTA shows intermediate stenosis (40-90%), consider FFR-CT to assess hemodynamic significance. 1

3. If CCTA shows obstructive disease (≥50% stenosis), proceed to invasive coronary angiography or optimize medical therapy based on symptom burden and ischemia assessment. 1

4. If CCTA is normal, the patient can be reassured and managed with guideline-directed preventive therapies. 5