CAD & angina Flashcards
What is Coronary Artery Disease (CAD)?
Insufficient perfusion of the coronary arteries due to decreased supply or increased demand.
What are the mechanical causes of decreased supply in CAD?
Atheroma, thrombosis, spasm, embolus, arteritis.
What are the causes of decreased blood flow in CAD?
Anemia, carboxy Hb, hypotension.
What is the most common cause of Coronary Artery Disease?
Obstruction (coronary atherosclerosis).
What triggers atherogenesis in CAD?
Initial endothelial injury/dysfunction due to mechanical shear stress, biochemical factors, immunological factors, inflammation, and genetic alteration.
What is the role of oxidized lipoproteins in CAD?
Increased permeability of endothelium to oxidized lipoproteins leads to accumulation taken up by macrophages, forming lipid-laden foam cells.
What are the components of a plaque in CAD?
Lipid core and fibrous cap.
What may a thrombus in CAD be adherent to?
Plaque due to superficial endothelial injury, endothelial denudation, or platelet adhesion.
What classification types fall under Acute Coronary Syndrome?
Unstable angina, Non-ST-elevation MI, ST-elevation MI.
What is a hemodynamically significant stenosis?
4 luminal cross-sectional area of ~ 70%.
What are some risk factors for CAD?
- Age (above 45 in men and above 55 in women)
- Male gender
- Family history of premature CAD
- Diabetes mellitus
- Hyperlipidemia
- Hypertension
- Smoking
- Obesity
- Sedentary lifestyle
- Hypercoagulability
- Homocysteinemia
- Certain drugs
- Heavy alcohol consumption
- Cocaine use.
Fill in the blank: A family history of premature CAD is defined as a 1st degree FH in male under ______ or female under ______.
55 years; 65 years.
True or False: Hyperlipidemia, especially T LDL, is a risk factor for CAD.
True.
How much does intermittent claudication increase the risk of CAD?
2-4 times.
How much does a myocardial infarction (MI) increase the risk of cerebrovascular accident (CVA) and heart failure (HF)?
3-6 times.
What cytokines are released by monocytes, macrophages, and damaged endothelium in CAD?
- PDGF
- TGF-B.
What is the significance of the fibrous cap in a plaque?
It is composed of smooth muscle and collagen, providing structural stability to the plaque.
What is the role of smooth muscle cells in plaque formation?
They migrate and proliferate, producing collagen that contributes to plaque formation.
What is angina?
Central/substernal heavy/tight/gripping chest pain that may radiate to jaw/arms caused by myocardial ischemia due to imbalance between blood supply and oxygen demand.
Angina can be categorized into stable and unstable types based on symptoms and triggers.
What characterizes stable angina?
Chest pain on exertion/emotion/stress, tight squeezing chest pain lasting 5-15 minutes, gradual onset, no pain at rest, occurs when oxygen demand exceeds perfusion, constant effort/duration, relieved by rest or GTN within minutes.
GTN refers to glyceryl trinitrate, a medication used to relieve angina.
What defines unstable angina?
Chest pain at rest, crescendo/deterioration in previously stable angina, or angina of recent onset (<24 h), due to reduced resting coronary blood flow, lasting more than 15 minutes, not relieved by rest.
Unstable angina is part of Acute Coronary Syndrome.
What are the components of the workup for angina?
Blood tests, chest x-ray, resting ECG, Holter monitoring, stress test, echocardiography.
Specific blood tests include CBC, coagulation profile, lipid profile, fasting glucose, HbA1c, TFT, RFT, and troponin.
What does a resting ECG typically show in angina?
Usually normal; may show ST depression and T-wave inversion during attack, normal between attacks.
ST depression indicates myocardial ischemia.
What should be done if a patient has unstable angina before a stress test?
Must be stabilized with medical treatment before stress testing due to risk of adverse events.
Stress testing is typically performed one month after the episode.
What does a positive ECG stress test reveal?
ST segment depression.
This indicates that the heart is not receiving enough blood during physical stress.
What are the indications for angiography in angina patients?
Severe angina or ischemic changes, ST depression >1mm at low workload within 6 minutes, or paradoxical fall in BP with exercise.
Baseline ECG changes like LBBB may require a myocardial perfusion scan.
What does stress echocardiography reveal if positive for ischemia?
Wall motion abnormalities.
This test assesses heart function under stress conditions.
Fill in the blank: Angina occurs when _______.
oxygen demand exceeds perfusion.
True or False: Stable angina can occur at rest.
False.
What is the role of Holter monitoring in angina workup?
To detect silent ischemia, particularly in diabetics and the elderly.
Silent ischemia may not present with typical symptoms.
What is the preferred initial treatment for stable angina?
BB (Beta Blockers)
Beta Blockers help reduce contractility, heart rate, and oxygen demand, leading to prolonged diastole and improved coronary perfusion.
Which medication is used for immediate angina relief?
Short-acting nitrates (GTN)
GTN stands for Glyceryl Trinitrate, a common short-acting nitrate used for angina.
What are dihydropyridines classified as?
CCB (Calcium Channel Blockers)
Dihydropyridines are a subclass of Calcium Channel Blockers used in angina treatment.
What should be avoided if a patient has low ejection fraction (EF)?
CCB (Calcium Channel Blockers)
The use of CCBs is discouraged in patients with low EF due to increased risk.
What medications are given to all patients with stable angina?
Aspirin & statins
These medications are crucial for cardiovascular event prevention.
List lifestyle modifications recommended for patients with stable angina.
- Smoking cessation
- Blood pressure control
- Weight control
- Exercise
- Optimal diabetes management
These modifications are essential for overall management of angina.
When is revascularization indicated in stable angina patients?
- Low EF
- LAD/Left main/3-vessel disease
- Severe angina despite maximum medical therapy
Revascularization options include PCI (Percutaneous Coronary Intervention) or CABG (Coronary Artery Bypass Grafting).
What is the acute treatment for unstable angina?
- Admit patient
- Oxygen (if <94)
- Morphine and nitrates
- Dual antiplatelets (aspirin + clopidogrel)
- Beta blockers
- LMWH (enoxaparin) for 48 hours
- Electrolyte replacement (K+ and Mg++)
These interventions aim to stabilize the patient and manage pain.
What is the maintenance treatment after acute unstable angina?
- Aspirin + clopidogrel for 6-9 months
- Beta blockers
- Nitrates (GTN)
- Statins
- Risk factor control
Long-term management is crucial to prevent recurrence and manage risk factors.
True or False: Revascularization is indicated if there is no improvement after 48 hours of medical therapy in unstable angina.
True
Revascularization may also be indicated if the patient is hemodynamically unstable or has a new murmur.
Fill in the blank: In patients with unstable angina, _______ is used for pain control.
Morphine
Morphine is a common analgesic used to manage pain in unstable angina.
What is the definition of variant angina?
Spontaneous episodes of angina with transient ischemic ST changes on ECG due to severe spasm of an epicardial coronary artery, usually near an atherosclerotic lesion.
This leads to a transient, abrupt, marked reduction in the luminal diameter and transient myocardial ischemia.
What is a characteristic pattern of episodes in variant angina?
Chronic pattern of episodes of angina, predominantly at rest, usually at night.
This condition is commonly found in young smokers.
What ECG changes are indicative of variant angina?
Ischemic ST-segment changes (ST elevation) during the episode, normal in between.
May be detected by Holter monitor.
What is the purpose of diagnostic coronary angiography in variant angina?
To exclude fixed obstructive coronary artery disease.
It may also include an acetylcholine provocation test to induce spasm.
What demographic is most commonly affected by variant angina?
Young smokers.
What lifestyle modifications are recommended for variant angina treatment?
Smoking cessation & lipid control.
What is the mainstay of therapy for variant angina?
Calcium channel blockers to reduce spasm.
What medication can be used to abort episodes of angina in variant angina?
Sublingual nitroglycerin.
This is to reduce the risk of life-threatening arrhythmias and myocardial infarction.
What is the role of long-acting nitrates in variant angina?
May help in controlling symptoms.
True or False: ACE inhibitors and beta blockers have a benefit in treating variant angina.
False.
Nonselective beta blockers should be avoided.
