What is the initial admitting workup for a patient presenting with stable angina?

Initial Workup for Stable Angina

The initial admitting workup for a patient presenting with stable angina should include a thorough clinical assessment, ECG, cardiac biomarkers, and risk stratification followed by appropriate functional testing. 1

Clinical Assessment

• Determine the characteristics of chest pain to classify it as typical angina, atypical angina, or non-cardiac chest pain based on:

  • Quality, location, and duration of pain
  • Factors that trigger and relieve the pain
  • Response to nitroglycerin 1

• Typical angina meets all three criteria:

  • Substernal chest discomfort of characteristic quality and duration
  • Provoked by exertion or emotional stress
  • Relieved by rest and/or nitroglycerin 1

• Assess severity of symptoms using the Canadian Cardiovascular Society Classification:

  • Class I: Ordinary activity does not cause angina
  • Class II: Slight limitation of ordinary activity
  • Class III: Marked limitation of ordinary activity
  • Class IV: Inability to carry out any physical activity without discomfort 1

• Evaluate cardiovascular risk factors:

  • Smoking, hyperlipidemia, diabetes mellitus, hypertension
  • Family history of premature CAD
  • Postmenopausal status in women 1

Initial Diagnostic Testing

• Obtain a 12-lead ECG at rest 1

  • Look for ST-segment depression, T-wave inversions, or Q waves suggesting previous MI

• Laboratory tests:

  • Complete blood count (hemoglobin and total white cell count provide prognostic information)
  • Fasting blood glucose and HbA1c
  • Fasting lipid profile
  • Serum creatinine for renal function
  • Thyroid function tests if clinically indicated 1

• Cardiac biomarkers (troponin or CK-MB) to exclude acute myocardial injury 1

• Chest X-ray (particularly in patients with suspected heart failure, valvular disease, or pulmonary disease) 1

Risk Stratification

• After initial assessment, patients should be categorized into low, intermediate, or high-risk groups based on clinical features, ECG findings, and biomarker results 1

• High-risk features requiring prompt coronary angiography:

  • Abnormal ECG consistent with ischemia
  • Positive cardiac biomarkers
  • Hemodynamic instability
  • Severe symptoms (CCS class III) despite maximal medical therapy 1, 2

Functional Testing

• Exercise ECG testing is the standard initial test for patients with:

  • Normal resting ECG
  • Ability to exercise
  • No digoxin use 1

• Stress imaging (echocardiography, nuclear, or MRI) is preferred for patients with:

  • Abnormal resting ECG (LBBB, LVH, ST-T abnormalities)
  • Previous revascularization
  • Inability to exercise
  • Equivocal exercise ECG results 1

• Coronary CT angiography may be appropriate for patients with:

  • Intermediate pretest probability of CAD
  • Normal or nondiagnostic ECG
  • Normal cardiac biomarkers 1

Echocardiography

• Echocardiography is indicated for:
  • Assessment of left ventricular function
  • Evaluation of suspected heart failure
  • Assessment of valvular disease
  • Patients with abnormal ECG, prior MI, or clinical evidence of heart failure 1

Coronary Angiography

• Direct referral for coronary angiography is indicated for patients with:
  • High-risk features on non-invasive testing
  • Severe symptoms (CCS class III) despite maximal medical therapy
  • Survivors of sudden cardiac death
  • Congestive heart failure
  • Special occupational requirements 1, 2

Common Pitfalls to Avoid

• Failing to distinguish between stable and unstable angina, as management pathways differ significantly 1

• Overlooking comorbid conditions that may precipitate "functional" angina:

  • Increased myocardial oxygen demand: hyperthyroidism, severe uncontrolled hypertension, aortic stenosis
  • Decreased myocardial oxygen supply: anemia, hypoxemia 1

• Performing unnecessary repeat testing in patients with known stable CAD and no change in symptoms 1

• Neglecting to assess for non-coronary causes of chest pain that may mimic angina 1