Coronary Artery Disease Flashcards
What is the difference between stable & unstable angina?
Stable: on exertion -> increased oxygen demand
Unstable: supply is decreased -> oxygen demand is unchanged
What is the criteria for typical angina?
- retrosternal chest pain
- provoked by exertion
- relieved by rest or nitroglycerin
atypical: 2 of the above
nonanginal: one or non of the above
What is the most common cause of CAD?
atherosclerosis
1- stable atherosclerotic plaque 2- vascular stenosis 3- increased resistance to blood flow in coronary arteries 4- decreased myocardial blood flow 5- myocardial ischemia
What is Poiseuille’s law?
vascular stenosis increases vascular resistance
- 50% reduction in the radius -> 16-fold increase in resistance
What is coronary steal syndrome?
blood flow to ischemic area is decreased
blood flow to normal areas are increased significantly
What are the clinical features of stable angina?
- retrosternal chest pain -> may be absent in geriatric, women, or diabetics
- dyspnea
- dizziness, palpitations
- restlessness, anxiety
- autonomic symptoms -> diaphoresis, nausea, vomiting, syncope
What is the best initial test for angina?
ECG
- usually normal in stable CAD
- Q waves -> prior MI
- ST-segment depression
- T wave inversion or T wave flattening
When should a stress test be done?
in case of TYPICAL ANGINA
- women < 60 years
- men < 40 years
in case of ATYPICAL ANGINA
- women > 50
- men of all ages
in case of NON-ANGINAL PAIN
- men > 40 years
- women > 60 years
How should a stress test be preformed?
target 85% of maximal heart rate -> stress induced ischemia
maximum heart rate = 220 - age
When should a stress test be terminated?
- diagnostic endpoint -> symptoms appear, signs of ischemia (ST), abnormal HR, abnormal BP
- after reaching target HR
- significant arrhythmias
- patient inability to continue
What is the gold standard method of investigation for CAD?
CARDIAC CATHETERIZATION
indicated in
- positive stress test
- noninvasive tests are non diagnostic/contraindicated
- angina occurs inspite of medical therapy
- acute MI with intent of perforating angiogram & PCI
What are the other non-invasive tests for CAD?
- coronary CT angiography (CCTA)
- coronary artery calcium (CAC) scoring
How should CAD be managed?
ALL PATIENTS -> pharmacotherapy
- secondary prevention of CAD + management of comorbidites
- antianginal medication
SELECT PATIENTS -> revascularization
- percutaneous coronary intervention (PCI)
- coronary artery bypass grafting (CABG)
What are the types of medical therapy for CAD?
ANTIANGINAL -> second line
- nitrates
- CCB
- metabolic modulators
SECONDARY PREVENTION & ANTIANGINAL
- Beta blockers -> first line
SECONDARY PREVENTION
- ACEi or ARBs -> patients with HTN, DM, LVEF <40%, & chronic kidney disease
- lipid lowering agents -> statins first then PCSK9 inhibitors
- anti platelet agents -> aspirin, clopidogrel
What are the acute coronary syndromes?
- unstable angina -> no troponins
- NSTEMI -> positive troponin without ST elevation
- STEMI -> positive troponin & ST elevation
What are the clinical features of unstable angina?
- dull squeezing pressure
- precipitated by stress
- dyspnea
- pallor
- nausea
- vomiting
- diaphoresis, anxiety
- dizziness, lightheadedness, syncope
What is seen with right ventricular infarction?
- hypotension
- elevated JVP
- clear lung fields
DO NOT GIVE NITRATES
What should be preformed as soon as ACS is suspected?
1- ECG -> repeat every 15-30 mins in first hour
2- if ST elevation is present -> D2B 90 minutes or D2N 30 minutes
3- troponin is most sensitive
4- CK-MB for reinfarction
What are the ECG changes that occur in STEMI?
tomb-stone appearance
- ST-elevation in V1 - V2 -> anterior -> LAD
- ST-elevation in V3 - V4 -> anterior -> distal LAD
- ST elevation in I, aVL -> lateral -> lateral circumflex
- ST elevation in II, III, aVF -> inferior -> right coronary artery
- left bundle branch block
- QRS duration > 120ms
- dominant S wave in V1
- broad monophasic R wave in lateral leads -> I, aVL
What is the fibrinolytic therapy used in STEMI?
D2N 30 mins
- tenecteplase
- alteplase
- reteplase
- streptokinase
How should NSTEMI & STEMI be managed?
MONA BASHC
- Morphine
- Oxygen
- Nitrates
- ASA
- Beta blockers -> if not at risk for HF or shock
- ACEi
- Statin
- Heparin
- Clopidogrel
What are the ECG changes in NSTEMI?
- no ST elevation
- nonspecific signs of ischemia -> ST depression & T wave inversion
What are the indications for urgent revascularization in NSTEMI?
- hemodynamic instability
- life-threatening arrhythmias
- refractory ischemic pain despite medical treatment
- acute heart failure
- mechanical complications
What are the complications of MI?
0 - 24hrs post infarction
- arrhythmias
- sudden cardiac death
- acute left heart failure
- cardiogenic shock
1 - 3 days
- acute pericarditis
3 - 14 days
- papillary muscle rupture
- free wall rupture -> tamponade
- ventricular septal rupture
- left ventricle pseudo aneurysm
2 weeks to months
- post myocardial infarction syndrome (Dressler syndrome)
- atrial & ventricular aneurysms
- arrhythmias
- HF
What type of angina is caused by transient coronary spasm?
Prinzmetal angina
- not affected by exertion & can occur at rest
- typically early morning
- in young women
- cigarette smoking, stress, hyperventilation, & exposure to cold precipitates it
How is Prinzmetal angina managed?
- smoking cessation
- calcium channel blockers -> verapamil, diltiazem, nifedipine
BETA BLOCKERS CONTRAINDICATED because they cause vasoconstriction
