Acute Coronary Syndromes Flashcards
What is coronary artery disease (CAD)?
Narrowing of coronary arteries due to atherosclerosis
What characterizes chronic coronary syndrome?
Patients with stable angina or no symptoms managed in an outpatient setting
What is the main pathophysiology of chronic coronary syndrome?
Fixed narrowing
What conditions are included in acute coronary syndrome?
Myocardial infarction (STEMI or NSTEMI) and unstable angina
What is the main pathophysiology of acute coronary syndrome?
Sudden occlusion
What does the acronym DIABETES stand for in coronary artery disease risk factors?
- D: Diabetes
- I: Inactivity and obesity/metabolic syndromes
- A: Age (older) and gender (men)
- B: Blood pressure high (hypertension)
- E: Elevated cholesterol (hypercholesterolemia)
- T: Tobacco smoking
- E: Ethnicity and family history
- S: Stress
Which group has a significantly higher risk of coronary artery disease?
Postmenopausal women compared to premenopausal women
What is the QRISK2 Cardiovascular risk score used for?
Screening tool that measures risk of patient having a heart attack or stroke within the next 10 years
What are the risk categories for the QRISK2 score?
- Low risk: Less than 10% (1 in 10 chance)
- Moderate risk: Between 10-20% (1 in 2 in 10 chance)
- High risk: More than 20% (over 1 in 5 chance)
What is the primary cause of coronary artery disease pathophysiology?
Mostly due to atherosclerosis affecting large and medium arteries, especially at branch points and bifurcations
What damages or dysfunctions the artery endothelium?
Due to tobacco or drug toxins, hyperlipidemia, hypertension, trauma
What happens to Low-density Lipoprotein (LDL) cholesterol in coronary artery disease?
Accumulates within dysfunctional tunica intima
What is fatty streak formation?
LDL accumulation causes monocyte recruitment, converting to macrophages and producing foam cells
What is atheroma formation?
Well-defined lipid core with macrophage debris and fibrous connective tissue
Describe atheroma morphology.
Raised lesion with soft yellow lipid core covered by white fibrous cap
What signals smooth muscle cell migration from tunica media during plaque progression?
Macrophage apoptosis
What are the effects of smooth muscle cell migration during plaque progression?
- Secretion of elastin and collagen
- Calcium deposition
- Neovascularization signals
What condition does plaque progression cause?
Chronic coronary syndrome
What is plaque disruption and thrombus formation?
It is the process where clot formation occurs due to endothelial dysfunction, leading to artery occlusion.
What causes clot formation in arteries?
Endothelial dysfunction causes loss of antithrombotic properties and inappropriate vasoconstriction.
What are the consequences of weakened plaques in arteries?
They can lead to aneurysm formation and rupture.
What conditions are caused by artery occlusion?
Acute coronary syndromes.
What is angina?
Chest pain that occurs due to myocardial ischaemia.
What causes myocardial ischaemia in angina?
Atherosclerotic plaques partially block coronary arteries.
What are the four characteristics of angina?
- Retrosternal pain that can spread to other areas
- Feelings of crushing pressure and tightness
- Precipitating factors (4 Es): Exertion, eating, emotional distress, extreme temperatures
- Attacks last a few minutes
What is the typical location of pain in angina?
Retrosternal area, arms, neck, lower jaw, and upper abdomen.
What feelings are associated with angina?
Crushing pressure and tightness in the chest.
What are the relieving factors for angina?
Rest and/or nitrates provide relief within 2 minutes.
How long do attacks of angina typically last?
A few minutes.
What is Class I angina severity classification?
Ordinary activity doesn’t cause angina.
What is Class II angina severity classification?
Slight limitation of ordinary activity.
What is Class III angina severity classification?
Marked limitation of ordinary activity.
What is Class IV angina severity classification?
Inability to carry on any physical activity without discomfort.
What is stable angina?
Stable atherosclerotic plaque narrows lumen, causing angina when oxygen demand exceeds supply during exertion or stress.
What are the two approaches to treating stable angina?
Symptomatic treatment and prognostic benefit.
What does symptomatic treatment for stable angina include?
Lifestyle management: Regular exercise, smoking cessation, psychosocial stress management, diet.
What are the medical management options for stable angina?
- Anti-anginals: Beta-blockers, calcium channel blockers, nitrates. 2. Vasculoprotective agents: Aspirin, statins, ACE inhibitors.
What are first-line anti-anginals?
Beta-blockers and calcium channel blockers, which slow heart rate and increase coronary perfusion in diastole.
Examples: Diltiazem, amlodipine.
What do nitrates do in the treatment of stable angina?
Reduce left ventricular end-diastolic pressure (LVEDP) and increase coronary vasodilation.
Example: Long-acting oral nitrates such as isosorbide mononitrate.
What is surgical management for stable angina?
Revascularization with Percutaneous coronary intervention (PCI) or Coronary Artery Bypass Graft (CABG).
When is PCI indicated?
If angina isn’t controlled on 2 anti-anginals, also used to treat NSTEMI MI urgently and emergency treatment of STEMI MI.
When is CABG indicated?
If angina isn’t controlled on 2 drugs, indicated in left main stem, proximal 3 vessel diseases, and for more complicated disease and higher risk.
What is unstable angina?
Atherosclerotic plaque becomes unstable and ruptures, causing partial occlusion of the artery due to bleeding and thrombosis.
What are the symptoms of unstable angina?
Angina at rest or minimal exertion and is prolonged.
What is variable/prinzmetal angina?
Coronary artery has intense vasospasm and suddenly narrows at night and during rest.
What are the most significant acute coronary syndromes?
STEMI, NSTEMI, unstable angina
What is STEMI?
Complete thrombus occlusion of artery, which causes myocardial infarction.
What is NSTEMI?
Partial thrombus occlusion of artery, which causes myocardial infarction.
What is unstable angina?
Athersclerotic plaque occlusion of artery becomes unstable and ruptures, causing partial occlusion of artery.
What are common presentations of acute coronary syndromes?
Angina, nausea/stomach pain, shortness of breath (SOB).
What is the first line investigation for acute coronary syndromes?
ECG findings.
What is the second-line investigation for acute coronary syndromes?
Cardiac biomarkers in blood test.
What does ST elevation indicate in ECG findings?
ST elevation, reciprocal ST depression in leads of other areas of heart.
What are elevated cardiac biomarkers in NSTEMI?
Creatine kinase-myocardial band (CK-MB) and Troponin.
What are the treatment components for acute coronary syndromes?
MONARCH BASIC.
What does ‘M’ stand for in MONARCH BASIC?
Morphine.
What does ‘O’ stand for in MONARCH BASIC?
Oxygen.
What does ‘N’ stand for in MONARCH BASIC?
Nitrates, e.g., Glyceryl trinitrate spray.
What does ‘A’ stand for in MONARCH BASIC?
Aspirin, an antiplatelet drug.
What does ‘R’ stand for in MONARCH BASIC?
Reperfusion with PCI or thrombolysis.
What is primary percutaneous coronary intervention (PCI)?
Balloon is threaded through a blood vessel to the blockage site and inflated to compress the plaque.
What is the first-line thrombolytic for thrombolysis?
Alteplase.
What does ‘C’ stand for in MONARCH BASIC?
Clopidogrel, but prasugrel or ticagrelor is preferred.
What does ‘H’ stand for in MONARCH BASIC?
Heparin.
What is the first step in secondary prevention for a patient?
Start beta-blocker as soon as the patient is hemodynamically stable.
When should beta-blockers be discontinued?
Beta-blockers can be discontinued after 12 months if LVEF is not reduced; otherwise, continue indefinitely.
What anticoagulant therapy should be used in secondary prevention?
Use anticoagulant or dual antiplatelet therapy (aspirin with another antiplatelet).
How long should aspirin be continued?
Aspirin should continue indefinitely.
How long can dual antiplatelet therapy be continued?
Dual antiplatelet therapy can be continued up to 12 months.
What is included in secondary prevention besides medications?
Statin and inhibitors (e.g., ACE inhibitor) should be started as soon as the patient is hemodynamically stable and continued indefinitely.
What is the goal of correcting risk factors in secondary prevention?
Correction of risk factors has an effectiveness of 83%.
What are some cardiac causes of chest pain?
Angina and pericarditis.
What are some gastrointestinal causes of chest pain?
GERD, peptic ulcers, biliary coeliac, esophageal spasms.
What are some musculoskeletal causes of chest pain?
Cervical radiculitis and costochondral syndrome.
What are the further investigations for coronary artery disease?
- Stress tests (Exercise ECG, Myocardial perfusion imaging, Dobutamine stress echocardiography, Stress MRI)
- Echocardiogram
- Angiography (Non-invasive CT coronary angiogram or invasive coronary angiogram)
- FBC
What does blue coloring indicate in myocardial perfusion imaging?
Blue coloring indicates extreme myocardial ischaemia on stress.
