What is the management approach for a patient presenting with symptoms suggestive of angina equivalent?

Management of Angina Equivalents

Symptoms suggestive of angina equivalents should be evaluated and treated with the same urgency and thoroughness as typical angina, as they represent potential manifestations of myocardial ischemia and require prompt diagnostic assessment and appropriate management. 1

What Are Angina Equivalents?

Angina equivalents are symptoms that occur due to myocardial ischemia but present differently from typical chest pain. According to the 2024 ESC guidelines, these include:

• Dyspnea or dizziness on exertion
• Pain in the arms, jaw, neck, or upper back
• Fatigue
• Emotional stress-triggered symptoms 1

Other presentations, particularly common in women, older adults, and non-white patients, include:

• Isolated unexplained new-onset or worsened exertional dyspnea
• Nausea and vomiting
• Diaphoresis
• Unexplained fatigue 1

Diagnostic Approach

Initial Assessment

1. Detailed symptom assessment:

   • Onset, duration, type, location, triggers, relieving factors, time of day 1
   • Relationship to exertion, stress, or relief with rest/nitroglycerin 1

2. Risk factor assessment:

   • Cardiovascular risk factors
   • Medical history
   • ECG (should be performed immediately, within 10 minutes of presentation) 1, 2

3. Laboratory testing:

   • Basic biochemistry
   • High-sensitivity C-reactive protein and/or fibrinogen plasma levels 1
   • Cardiac biomarkers (high-sensitivity troponin) 2, 3

Risk Stratification

Calculate pre-test likelihood of obstructive coronary artery disease (CAD) using the Risk Factor-weighted Clinical Likelihood model 1. Adjust this estimate using:

• Examination of peripheral arteries
• Resting ECG findings
• Resting echocardiography
• Presence of vascular calcifications on previous imaging tests 1

Further Diagnostic Testing

Based on pre-test likelihood:

• Very low likelihood (≤5%): Consider deferring further diagnostic tests 1
• Low likelihood (>5%-15%): Consider coronary artery calcium scoring (CACS) to reclassify risk 1
• Moderate to high likelihood: Proceed with non-invasive or invasive testing based on clinical presentation 1

For suspected vasospastic angina, consider ambulatory ECG monitoring 1.

Management Approach

Pharmacological Therapy

First-line medications for symptom control:

• Beta-blockers (e.g., metoprolol): Reduce heart rate, blood pressure, and myocardial oxygen demand 4, 5
• Calcium channel blockers: Alternative first-line therapy, especially when beta-blockers are contraindicated 5
• Short-acting nitrates: For acute symptom relief 5

Second-line medications (if symptoms persist despite first-line therapy):

• Ranolazine: Particularly effective for chronic stable angina, with minimal effects on heart rate and blood pressure 6, 5
• Long-acting nitrates: For prevention of angina episodes 5

Special Considerations

Angina with Normal Coronary Arteries (ANOCA/INOCA)

For patients with symptoms suggestive of ischemia but no obstructive CAD on angiography:

• Consider microvascular angina, which requires specific diagnostic testing for coronary microvascular dysfunction 7
• Treatment may include beta-blockers, ACE inhibitors, and statins 8
• This condition is more common in women and carries a worse prognosis than previously thought 8

High-Risk Features

For patients with high-risk features:

• Prolonged (>20 min) ongoing rest pain
• New or worsening heart failure symptoms
• Hemodynamic instability
• Dynamic ECG changes

Consider urgent invasive coronary angiography and potential revascularization within 24-48 hours 1, 3

Follow-up Recommendations

• Evaluate every 4-6 months during the first year of therapy
• Annual evaluations after the first year if the patient is stable 1
• Assess for:
  • Changes in physical activity level
  • Changes in symptom frequency or severity
  • Medication tolerance
  • Success in risk factor modification
  • Development of new comorbidities 1

Common Pitfalls to Avoid

1. Dismissing atypical symptoms: Angina equivalents are often misdiagnosed, especially in women, older adults, and non-white patients 8

2. Inadequate risk stratification: Failing to properly assess risk can lead to delayed diagnosis and treatment 1

3. Assuming benign prognosis with normal coronaries: Patients with symptoms but normal coronary arteries may have microvascular dysfunction with increased risk of adverse events 8

4. Abrupt discontinuation of beta-blockers: This can lead to severe exacerbation of angina, myocardial infarction, or ventricular arrhythmias 4

5. Overlooking non-atherosclerotic causes: Consider vasospastic angina, microvascular dysfunction, or other non-obstructive causes when typical CAD is not found 7