What is the management of chronic stable angina?

Management of Chronic Stable Angina

The management of chronic stable angina requires a combination of pharmacological therapy, lifestyle modifications, and selective revascularization, with beta-blockers, aspirin, statins, and ACE inhibitors forming the cornerstone of treatment to reduce mortality and morbidity. 1, 2

First-Line Pharmacotherapy

Medications to Prevent MI and Death

1. Antiplatelet Therapy

   • Aspirin 75-150 mg daily 1, 2
   • Clopidogrel when aspirin is absolutely contraindicated 1

2. Beta-Blockers

   • First-line therapy for symptom control 1, 2
   • Particularly beneficial in post-MI patients 2
   • Target heart rate: 50-60 bpm 2

3. Lipid-Lowering Therapy

   • High-intensity statin therapy targeting LDL-C <70 mg/dL 1, 2

4. ACE Inhibitors

   • Recommended for all patients with documented CAD 1, 2
   • Particularly important for patients with hypertension, diabetes, or LV dysfunction 2

Medications for Symptom Relief

1. Immediate Relief

   • Sublingual nitroglycerin or nitroglycerin spray 1, 2

2. Maintenance Therapy

   • Beta-blockers (first-line) 1, 2
   • Long-acting calcium channel blockers when beta-blockers are contraindicated or as add-on therapy 1, 2
   • Long-acting nitrates as add-on therapy (with a daily nitrate-free interval of 10-12 hours to prevent tolerance) 2
   • Ranolazine as add-on therapy for patients who remain symptomatic despite other antianginal medications 3, 4

Revascularization Options

Indications for Coronary Angiography

• Symptoms not adequately controlled by medical therapy 2
• Marked limitation of ordinary activity (Canadian Cardiovascular Society class III) despite maximal medical therapy 1

Revascularization Approaches

1. Percutaneous Coronary Intervention (PCI)

   • Effective for symptom relief when medical therapy fails 2
   • No evidence for mortality reduction compared to medical therapy 2

2. Coronary Artery Bypass Grafting (CABG)

   • Highly effective for symptom relief 2
   • Reduces mortality in specific subgroups (left main stem stenosis, proximal LAD stenosis, three-vessel disease with impaired LV function) 2

Alternative Therapies for Refractory Angina

For patients who cannot be managed adequately by medical therapy and are not candidates for revascularization:

1. Surgical Laser Transmyocardial Revascularization (TMR)

   • Class IIa recommendation (Level of Evidence: A) 1
   • Creates transmural endomyocardial channels to improve myocardial revascularization 1

2. Enhanced External Counterpulsation (EECP)

   • Class IIb recommendation (Level of Evidence: B) 1
   • Decreases angina frequency and improves time to exercise-induced ischemia 1
   • Generally well tolerated with improvement in symptoms in 75-80% of patients 1

3. Spinal Cord Stimulation (SCS)

   • Class IIb recommendation (Level of Evidence: B) 1
   • Provides analgesia for refractory chronic angina 1
   • Requires accurate placement of stimulating electrode in the dorsal epidural space 1

Risk Factor Modification

1. Metabolic Syndrome Management

   • Weight reduction and increased physical activity 1
   • Control of associated risk factors:
     • Abdominal obesity (waist circumference >103 cm in men, >88 cm in women)
     • Hypertension (target <130/85 mmHg)
     • Dyslipidemia (triglycerides >150 mg/dL, low HDL)
     • Hyperglycemia (fasting glucose ≥110 mg/dL) 1

2. Smoking Cessation

   • Critical for reducing cardiovascular risk 2, 4

Follow-up and Monitoring

• Every 4-6 months during the first year of therapy 1, 2
• Annually thereafter if stable 1, 2
• Monitor:
  1. Changes in physical activity level
  2. Anginal symptoms (frequency, severity)
  3. Medication tolerance and adherence
  4. Success in risk factor modification
  5. Development of new comorbidities 1

Clinical Pearls and Pitfalls

• Avoid dipyridamole and chelation therapy as they are not recommended for preventing MI or death or reducing symptoms 1
• Antioxidant supplements (vitamins C, E) have shown no benefit in preventing or treating CAD 1
• Hormone replacement therapy is not recommended for CAD prevention in postmenopausal women 1
• Ranolazine may be particularly effective for patients with microvascular angina and endothelial dysfunction 4
• Nitrate tolerance can develop; ensure a daily nitrate-free interval of 10-12 hours 2
• Percutaneous TMR is still considered experimental therapy and is not FDA-approved 1

The management of chronic stable angina requires a comprehensive approach that addresses both symptom relief and prevention of cardiovascular events. While newer antianginal agents have emerged, traditional therapies like beta-blockers, nitrates, and calcium channel blockers remain the foundation of treatment, with aspirin, statins, and ACE inhibitors providing crucial cardiovascular protection.