What is the workup for chest pain post percutaneous coronary intervention (PCI) with stent placement?

Workup for Chest Pain Post Stent Placement

The workup for chest pain after percutaneous coronary intervention (PCI) with stent placement should begin with a 12-lead ECG and assessment of cardiac biomarkers to rule out ischemic complications, followed by appropriate diagnostic testing based on clinical presentation and risk factors. 1, 2

Initial Assessment

Immediate Evaluation

• Obtain a 12-lead ECG to compare with pre-discharge ECG 2
• Assess vital signs and perform targeted physical examination
• Administer sublingual nitroglycerin for symptom relief 2
• Consider cardiac biomarkers (troponin) if pain is severe or persistent 2

Key Clinical Features to Differentiate Causes

• Timing: Immediate post-PCI vs. delayed onset
• Character: Positional vs. exertional vs. continuous
• Response to nitroglycerin
• Associated symptoms: dyspnea, diaphoresis, nausea
• ECG changes: ST-segment deviation, new Q waves, T-wave changes

Diagnostic Algorithm

High-Risk Features (Require Urgent Evaluation)

• New ST-segment changes on ECG
• Hemodynamic instability
• Severe, persistent, or recurrent pain
• Elevated cardiac biomarkers
• Pain unresponsive to nitroglycerin

For Patients with High-Risk Features

1. Immediate cardiology consultation
2. Consider repeat coronary angiography to evaluate for:
   • Stent thrombosis
   • Coronary dissection
   • Side branch occlusion
   • Coronary spasm

For Patients with Low-Risk Features

1. Non-invasive testing:
   • Stress testing with imaging (after appropriate time post-PCI)
   • CT coronary angiography (if appropriate)
2. Consider other causes:
   • Non-ischemic "stretch pain" (common after stenting) 3
   • Pericarditis
   • Musculoskeletal pain
   • Gastrointestinal causes

Evidence-Based Considerations

The American Heart Association guidelines note that ST-segment monitoring for 4-8 hours post-PCI is beneficial for evaluating chest pain in the immediate post-intervention period 1. This monitoring helps distinguish ischemic from non-ischemic causes of chest pain.

Studies have shown that chest pain is common after coronary interventions, occurring in approximately 23% of patients within 72 hours 4. However, only a minority of these patients have true ischemic events. Non-ischemic chest pain appears to be more common after stent implantation compared to balloon angioplasty alone (41% vs. 12%), likely due to continuous stretching of the arterial wall by the stent 3.

Important Clinical Pearls

• ECG changes are a sensitive marker for angiographic abnormalities and confer a higher risk of non-Q-wave myocardial infarction 4
• Patients with chest pain but no ECG changes after successful stent placement may not require urgent recatheterization 4
• Coronary vasoreactivity may be enhanced after stent placement, causing chest pain in approximately 20% of patients without in-stent restenosis 5
• Post-stent chest symptoms can persist up to 10 weeks after discharge and are often recurrent 6

Common Pitfalls to Avoid

1. Dismissing chest pain as non-cardiac without appropriate evaluation
2. Failing to obtain an ECG during symptoms
3. Not considering stent thrombosis in patients on inadequate antiplatelet therapy
4. Overlooking non-coronary causes of chest pain
5. Performing unnecessary invasive testing in patients with typical non-ischemic post-stent pain

Remember that premature discontinuation of antiplatelet therapy increases the risk of stent thrombosis, myocardial infarction, and death 7. Ensure patients are maintaining adherence to prescribed dual antiplatelet therapy.