What are the contraindications for coronary angiography?

Contraindications for Coronary Angiography

Coronary angiography should not be performed in patients with extensive comorbidities where risks of revascularization outweigh benefits, in patients with acute chest pain and low likelihood of acute coronary syndrome, or in patients who will not consent to revascularization regardless of findings. 1

Absolute Contraindications

• Patient refusal or lack of informed consent - Patients who explicitly refuse the procedure or are unable to provide informed consent 2
• Patients who will not consent to revascularization regardless of findings 1
• Patients with extensive comorbidities (e.g., liver or pulmonary failure) where risks of revascularization outweigh potential benefits 1

Relative Contraindications

Clinical Scenarios

• Acute chest pain with low likelihood of acute coronary syndrome 1
• Preserved left ventricular function (EF >50%) with low-risk criteria on noninvasive testing 1
• Asymptomatic patients with no evidence of ischemia on noninvasive testing 1
• Low-risk patients according to clinical criteria who have not undergone noninvasive risk testing 1

Patient-Related Factors (Higher Risk Groups)

• Advanced age (>70 years) - Not an absolute contraindication but increases risk 1
• Marked functional impairment - Canadian Cardiovascular Society class IV angina or NYHA class IV heart failure 1
• Severe left ventricular dysfunction 1
• Severe valvular disease 1
• Severe renal insufficiency - Especially with diabetes mellitus due to increased risk of contrast-induced nephropathy 1
• Severe hepatic or pulmonary disease 1
• Bleeding disorders - Increased risk of procedural complications 1
• History of allergic reaction to radiographic contrast material 1
• Active infective endocarditis with large mobile vegetations - Due to risk of vegetation dislodgement, though evidence suggests it may be performed with caution 3

Complications to Consider When Evaluating Contraindications

Coronary angiography carries a 1.5% incidence of procedural complications, including:

• Death
• Stroke (0.05-0.1% in diagnostic procedures) 4
• Myocardial infarction
• Bleeding
• Infection
• Contrast allergic or anaphylactoid reactions
• Vascular damage
• Contrast-induced nephropathy
• Arrhythmias
• Need for emergency revascularization 1

Special Considerations

Contrast Allergy

• For patients with severe contrast allergy to iodinated contrast, gadolinium-based contrast can be considered as an alternative, though with caution due to:
  • Reduced image quality
  • Potential for serious complications including malignant cardiac arrhythmias (21% risk of severe complications) 5

Renal Dysfunction

• Increased risk of contrast-induced nephropathy in patients with:
  • Pre-existing renal insufficiency
  • Diabetes mellitus 1
• Preventive measures should be considered (hydration, minimizing contrast volume)

Decision-Making Algorithm

1. Assess clinical necessity: Is coronary angiography indicated based on symptoms, noninvasive testing, or clinical presentation?
2. Evaluate risk-benefit ratio: Do potential benefits outweigh risks?
3. Consider patient preferences: Has the patient provided informed consent and is willing to undergo potential revascularization if indicated?
4. Assess contraindications: Are any absolute contraindications present?
5. Evaluate risk factors: Are relative contraindications present that might increase procedural risk?
6. Consider alternatives: Would CT coronary angiography or other noninvasive testing be more appropriate?

Key Pitfalls to Avoid

• Performing coronary angiography in patients who will not consent to revascularization regardless of findings
• Underestimating the risk of contrast-induced nephropathy in patients with renal dysfunction
• Failing to obtain proper informed consent discussing risks, benefits, and alternatives
• Performing angiography in patients with low likelihood of coronary artery disease without prior noninvasive testing
• Overlooking the increased risk in elderly patients with multiple comorbidities