Lecture on Angina
Introduction to Angina
- Angina = Chest pain due to limited blood flow to the heart.
- Indicates a warning sign of inadequate blood supply to heart muscles (myocardium).
- Prolonged limited blood flow can lead to heart sections dying.
Blood Supply to the Heart
- Coronary Arteries: Primary source of blood supply to the heart.
- Left and Right Coronary Arteries originate from the Aorta.
- Act as main suppliers, branching out to further deliver oxygenated blood.
Left Coronary Artery
- Branches into the Left Anterior Descending and Left Circumflex arteries.
- Feeds the left atrium, left ventricle, and interventricular septum.
- Blockage can lead to reduced cardiac output and heart failure.
Right Coronary Artery
- Branches into Right Marginal and Right Posterior Descending arteries.
- Supports the right atrium, right ventricle, and important electrical nodes (SA node, AV node).
- Blockage can affect heart rhythm (dysrhythmias).
Types of Angina
1. Stable Angina
- Known as exertional angina, triggered by physical/emotional stress.
- Due to fatty plaque in arteries causing stiffness and limited dilation.
- Use of nitroglycerin (vasodilator) for relief.
- Key characteristics: predictable, short-lived, resolved with rest/nitroglycerin.
- Troponin levels usually negative; ECG normal at rest but may show changes with exertion.
- Lifestyle changes recommended: low-fat/low-sodium diet, quit smoking, manage diabetes.
2. Unstable Angina
- Known as pre-infarction angina, can lead to a myocardial infarction (heart attack).
- Occurs with minimal activity or at rest.
- Caused by ruptured plaque leading to clot formation (thrombus).
- Key characteristics: unexpected, no relief with rest, lasts >15 minutes.
- Immediate medical treatment required; troponin usually negative; ECG may show transient changes.
3. Variant Angina (Prinzmetal Angina)
- Caused by vasospasm of coronary arteries.
- Occurs at rest, often at night or morning.
- Risk factors: vasoconstrictive drugs, smoking, alcohol, certain vascular disorders.
- Treated with nitroglycerin and calcium channel blockers.
Diagnostic and Treatment Considerations
- Troponin levels and ECG for assessing angina.
- Use of nitroglycerin for stable and variant angina.
- Medications: beta-blockers, calcium channel blockers, ACE inhibitors, ARBs, and aspirin.
- Heart catheterization for severe cases.
Lifestyle and Preventative Measures
- Low-fat, low-sodium diet.
- Quit smoking; manage blood glucose and blood pressure.
- Statins for cholesterol management.
- Antiplatelet therapy to prevent clot formation.
Conclusion: Understanding the types of angina, their causes, and treatment options is crucial for effective management and prevention of further cardiovascular complications.