Angina Pectoris is a clinical syndrome characterized by chest pain or discomfort due to myocardial ischemia (inadequate oxygen supply to the heart muscle). It is a hallmark symptom of Coronary Artery Disease (CAD) and often precedes myocardial infarction (heart attack).
While angina itself is not life-threatening, it serves as a warning sign of underlying cardiac pathology. Understanding its types, manifestations, and management strategies is crucial for timely intervention and prevention of complications.
Types of Angina
Angina is classified based on its pattern, severity, and underlying cause.
1. Stable Angina (“Predictable”)
- Triggered by exertion or emotional stress.
- Caused by increased myocardial oxygen demand in the setting of fixed coronary artery stenosis.
- Relieved by rest or nitroglycerin.
- Predictable in nature (patients often know what activities trigger their chest pain).
2. Unstable Angina (“Pre-infarction”)
- Occurs at rest and with increasing frequency or severity.
- Signals worsening ischemia due to plaque rupture and impending myocardial infarction.
- Considered a medical emergency.
3. Prinzmetal’s / Variant Angina
- Caused by coronary artery vasospasm rather than fixed plaque.
- Occurs at rest, often at night or early morning.
- Associated with transient ST-segment elevation on ECG.
- Relieved by calcium channel blockers and nitrates.
Clinical Manifestations
The symptoms of angina are related to myocardial hypoxia.
- Chest pain: Heavy, squeezing, or pressure-like sensation, often radiating to neck, jaw, shoulders, or arms.
- Dyspnea (shortness of breath)
- Unusual fatigue and weakness
- Pallor (pale appearance)
- Diaphoresis (sweating)
- Nausea or dizziness in some patients
Key Point: Chest pain lasting more than 20 minutes at rest may indicate myocardial infarction, not just angina.
Diagnosis of Angina
Diagnosis involves a combination of clinical history, physical examination, and diagnostic tests.
1. Electrocardiogram (ECG)
- ST-segment depression in stable angina.
- Transient ST-elevation in Prinzmetal’s angina.
2. Exercise Stress Test
- Evaluates cardiac function during physical exertion.
3. Echocardiogram
- Detects wall motion abnormalities due to ischemia.
4. Coronary Angiography
- Gold standard for detecting coronary artery stenosis.
Treatment Goals
- Reduce myocardial oxygen demand.
- Improve oxygen supply to the heart muscle.
- Prevent complications such as myocardial infarction.
Interventions for Angina
Reperfusion Procedures
1. Percutaneous Coronary Intervention (PCI)
- Minimally invasive procedure using angioplasty and stent placement.
- Restores blood flow in blocked coronary arteries.
- Surgical procedure where blood is rerouted around blocked arteries using grafts.
- Recommended in severe multi-vessel CAD or when PCI is not feasible.
Drug Therapy
Several drug classes are used in combination to manage angina:
1. Nitrates
- Vasodilators that reduce myocardial oxygen demand.
- Rapidly relieve angina symptoms (usually given sublingually).
- Example: Nitroglycerin.
2. Calcium Channel Blockers
- Relax blood vessels, improving oxygen delivery.
- Reduce arterial spasm (useful in Prinzmetal’s angina).
- Examples: Amlodipine, Diltiazem, Verapamil.
3. Beta Blockers
- Decrease myocardial oxygen consumption.
- Reduce heart rate and contractility.
- Examples: Metoprolol, Atenolol.
4. Antiplatelet / Anticoagulants
- Prevent platelet aggregation and thrombus formation.
- Essential in unstable angina and after PCI.
- Examples: Aspirin, Clopidogrel, Heparin.
Lifestyle Modifications
In addition to medical and surgical interventions, lifestyle changes play a vital role in reducing angina frequency and severity.
- Quit smoking (reduces vasoconstriction and plaque buildup).
- Follow a heart-healthy diet (low sodium, low cholesterol, high fiber).
- Exercise regularly (as advised by physician).
- Manage hypertension and diabetes.
- Reduce stress through meditation, yoga, or relaxation techniques.
Comparative Table: Types of Angina
| Type | Trigger | Occurrence | ECG Findings | Relief |
|---|---|---|---|---|
| Stable Angina | Exertion, stress | Predictable | ST depression | Rest, nitrates |
| Unstable Angina | At rest, more frequent | Unpredictable, pre-MI | ST/T changes | Requires urgent care |
| Prinzmetal’s Angina | Coronary vasospasm | At rest, often night/early morning | Transient ST elevation | Nitrates, calcium channel blockers |
Conclusion
Angina Pectoris is not just chest pain—it is a warning sign of coronary artery disease. Identifying its type and initiating appropriate treatment is essential to prevent myocardial infarction and improve patient outcomes.
- Stable angina → Predictable, exertional, relieved by rest/nitrates.
- Unstable angina → Emergency, occurs at rest, precursor to heart attack.
- Prinzmetal’s angina → Vasospasm-induced, reversible with vasodilators.
Combining drug therapy, lifestyle modification, and possible revascularization procedures (PCI or CABG) ensures optimal care for angina patients.
FAQs on Angina Pectoris
Q1: How do I know if my chest pain is angina or a heart attack?
Angina usually lasts a few minutes and is relieved by rest or nitroglycerin. A heart attack lasts longer, occurs at rest, and is not relieved by medication.
Q2: Can angina go away permanently?
With proper treatment, lifestyle changes, and revascularization procedures, angina can be significantly reduced but underlying CAD often persists.
Q3: Why is unstable angina dangerous?
It indicates plaque rupture and risk of complete artery blockage, making it a medical emergency.
Q4: Can anxiety mimic angina?
Yes, anxiety can cause chest pain, but true angina is usually triggered by exertion and associated with ischemia.
Q5: Which type of angina is most responsive to calcium channel blockers?
Prinzmetal’s (variant) angina caused by vasospasm responds best to calcium channel blockers and nitrates.
