Is chest pain not located at the coronary artery bypass graft (CABG) surgical site normal after CABG?

Chest Pain Not at the Insertion Site After CABG: Causes and Management

Chest pain away from the surgical site after coronary artery bypass graft (CABG) surgery is common and can have multiple causes, with musculoskeletal pain being the most frequent etiology. 1

Common Causes of Non-Insertion Site Chest Pain Post-CABG

Musculoskeletal Causes

• Post-sternotomy pain syndrome, defined as discomfort persisting for at least 2 months after thoracic surgery without apparent cause, affects between 7% and 66% of patients 1
• Women experience higher prevalence of post-sternotomy pain within the first 3 months (51.4% vs 31.3% in men), though this difference disappears after 3 months 1
• Sternal wire dehiscence can cause retrosternal chest pain even years after CABG 2

Ischemic Causes

• Graft failure due to:
  • Technical issues at anastomotic sites 1
  • Thrombosis within grafts 1
  • Graft intimal hyperplasia 1
  • Vasospasm within arterial grafts 1
• Progressive atherosclerosis in bypass grafts or native vessels 1
• Saphenous vein graft failure rates: 10-20% at 1 year, approximately 50% by 10 years 1
• Internal mammary artery grafts have better longevity with 90-95% patency at 10-15 years 1

Other Causes

• Sympathetically mediated chest pain (rare) presenting with hyperalgesia to light touch 3
• Coronary steal syndrome due to fistula formation 4, 5
• Pericarditis 1
• Pulmonary embolism 1
• Sternal wound infection 1

Evaluation of Post-CABG Chest Pain

For Non-ACS Presentation:

• Stress imaging is recommended to evaluate for myocardial ischemia 1
• Coronary CT angiography (CCTA) is effective for evaluating graft stenosis or occlusion with 99% sensitivity and specificity for detecting complete graft occlusions 1
• CCTA is particularly useful for assessing bypass grafts due to:
  • Larger vessel size
  • Decreased vessel calcification
  • Decreased motion compared to native vessels 1

For Indeterminate/Nondiagnostic Stress Test:

• Invasive coronary angiography (ICA) is recommended 1
• ICA is particularly useful when angiographic findings would likely impact therapeutic decisions 1

High-Risk Features Warranting ICA:

• New resting left ventricular systolic dysfunction (EF <35%) not explained by non-coronary causes 1
• Significant ST-segment depression at low workload or persisting into recovery 1
• Exercise-induced ST-segment elevation 1
• Exercise-induced ventricular tachycardia/fibrillation 1
• Severe stress-induced left ventricular systolic dysfunction 1
• Stress-induced perfusion abnormalities involving ≥10% of myocardium 1

Management Considerations

For Ischemic Causes:

• Emergency CABG is recommended after failed PCI in the presence of ongoing ischemia or threatened occlusion with substantial myocardium at risk 1
• For patients with resuscitated sudden cardiac death or sustained ventricular tachycardia thought to be caused by significant CAD and resultant myocardial ischemia, CABG is recommended 1

For Musculoskeletal Pain:

• Pain modulators and analgesics 3
• For sympathetically mediated chest pain, stellate ganglion block may be effective 3

For Post-Sternotomy Pain Syndrome:

• Recognition that this is a common complication affecting up to 39.3% of patients following cardiac surgery 6
• Risk factors include younger age (55% in those under 60 years vs 34% in those over 70), pre-operative angina, and being overweight or obese at time of surgery 6

Key Points to Remember

• Chest pain not at the insertion site is common after CABG and has multiple potential causes 1
• Musculoskeletal pain from sternotomy is the most common cause 1
• Patients should be evaluated for both ischemic and non-ischemic causes 1
• Graft failure rates increase over time, with saphenous vein grafts having significantly higher failure rates than arterial grafts 1
• Chronic post-CABG pain can significantly impact quality of life and should be addressed appropriately 6