Flashcards in PMT, Johnston - CAD: Angina-Stable/Unstable Deck (46):
What is the major underlying cause of CAD (and the cause of 90% of MI and most HF)
What is angina pectoris?
Chest discomfort, the most frequent expression of myocardial ischemia.
What is Chronic Stable Angina?
A consequence of imbalance between oxygen supply-demand.
Examples of supply angina
Decreased oxygen delivery to tissue leading to ischemia >> coronary vasoconstriction, platelets releasing 5HT and TXA2.
Examples of demand angina
Increase myocardial ocygen requirement and workload can lead to ischemia >> exercise, stress, emotion, fever, LVH due to AS, Anemia (low O2 carrying capacity).
The three disturbances/effects of ischemia.
1) Mechanical consequences
2) Biochemical consequences
3) Electrical consequences
Examples of MECHANICAL consequences caused by ischemia (3).
1) HF (LVF and/or RVF)
2) Angina, if ischemia is prolonged or develop coronary occlusion, may lead to myocardial necrosis.
3) Segmental akinesis, bulging (dyskinesis)
Examples of BIOCHEMICAL consequences caused by ischemia (3).
1) FA can't be oxidized
2) Increased lactate production
3) Reduced pH with metabolic acidosis
Higher lactate is associated with what?
Examples of ELECTRICAL consequences caused by ischemia (5).
1) T wave inversion
2) Transient displacement of ST segment
3) ST Depression - subendocardial (only inner infarcted)
4) ST Elevation - subepicardial (all infarcted)
5) Electrical instability - VT, Vfib
What will angina look like on ECG?
50% of the time the ECG will look normal.
See T wave inversion, think what?
Heaviness in retrosternal region. Pain radiates to base of neck and into jaw. Radiates to L shoulder and arm. Crescendo/decrescendo for 20 minutes.
PE in angina:
S3 gallop means what?
Systolic murmur over apex with radiation into left axilla means what?
S3 indicates LV dysfunction leading to HF
Murmur is likely mitral regurgitation due to impaired blood supply to papillary muscles.
Anginal systolic murmur in what locations is due to lesion of what vessel?
Inferior and inferior-posterior due to RCA impairment.
What are non-chest pain symptoms of chronic IHD (5)?
2. Non chest locations of discomfort (exertional or at rest), mid-epigastric or abdominal
4. Excessive fatigue and weakness
5. Dizziness and syncope.
Why does the threshold of activity level that provokes angina attacks vary among patients?
Fixed CA stenosis/fixed O2 supply; produces ischemia because of increased oxygen demand.
What is Levine's Sign - description and what it means.
Substernal discomfort, clinched fist - discomfort that goes along with ANGINA.
What situations may precipitate angina?
Eating a heavy meal or cold exposure.
FHx in angina
PE in angina; signs of risk factors
Often normal, BUT:
Diabetic skin lesions,
*Absent peripheral pulses!
What is xanthelasma and what does it indicate?
Soft, yellowish lipid deposits on eyelids. Indicative of angina.
What four things can MIMIC angina in absence of CAD?
3) Pulmonary HTN
4) Hypertrophic Cardiomyopathy
What is Acute Coronary Syndrome (ACS)?
UNSTABLE ANGINA and NSTEMI.
What is UA?
Unstable angina - new or worsening chest pain.
Pain lasting longer than 20 minutes, less effort to provoke (sometimes wakes from sleep), more meds to relieve, no evidence of myocyte necrosis (no cardiac enzyme elevation).
What is NSTEMI?
NSTEMI ACS - Non-ST Elevation Myocardial Infarction:
Chest pain WITH elevation of cardiac enzymes and WITHOUT ST elevation.
What is the pathology of ACS?
Most have an atherosclerotic plaque rupture or erosion; platelet aggregation and thrombus leading to partial occlusion of artery.
Is ST-elevation or depression more common in STABLE ANGINA?
ST-depression more common = subendocardial injury ischemia
How does the magnitude of ST-depression correlate with prognosis in UA/NSTE ACS?
1mm+ in 2 or more leads >> 4x as likely to die within 1 year.
2mm+ >> 6x as likely to die within 1 year.
2mm+ in more than 1 region of ECG >> mortality is 10 fold.
DDx of NSTE ACS?
PE - ECG changes, elevated troponin
Stress Cardiomyopathy (Takotsubo Syndrome) = deeply inverted T wave
Labs in CAD
Inc. Troponin w/in 2-4 hrs.
Inc. CK-MB w/in 3-6 hrs.
Inc. BNP = increased mortality
Fasting Lipid Profile
Prognosis: Signs of high risk for coronary event.
1) Postive stress test at low workload
2) ST depression greater than 5 min after completion of test
3) Decrease in BP - syst fall more than 10mmHg during exercise.
4) VT during exercise
5) Reduce dEF during exsercise (Stress echo)
Stress Testing CI
Recent MI or acute MI.
Tests for Coronary Event Prognosis
Pharmacological Stress Test
Nuclear Myocardial Perfusion Imaging (LBBB, LVH, digitalis effect)
*Coronary Angiography: (cardiac Cath)
*Percutaneous Coronary Intervention and Coronary Artery Bypass Graft (PCI and CABG)
What's coronary angioplasty used for?
Gld std for CAD if pt is considered for revascularization with PCI or CABG.
What is PCI?
What is CABG?
Both: Myocardial revascularization
PCI - 90% successful in 1 - 2 VESSEL DISEASE, followed by stent insertion.
CABG - for LAD or 3 VESSEL DISEASE
Pharmacologic interventions to prevent MI/Death/Reduce symptoms.
ACEi - good for DM/renal
Nitro/Nitrates - drug of choice! (SL)
CCB - use Verapamil cautiously in HF
Aspirin tx MOA
COX-i leading to TXA2-i platelet activation
BB tx MOA, special, CI
MAO - bind cats to beta-receptor to DECREASE HR, workload, contractibilty/O2 demand, ischemia and symptoms,
- DECREASES MI MORTALITY
CI - decompensated HF, hypoT, advanced AV block
ACEi tx MOA, special, uses
Blocks conversion of Ang1 to Ang2
- DECREASES MI MORTALITY
- Use in DIABETICS and LV systolic dysfunction
Nitrates tx MOA, special, uses
Vasodilators vascular smooth msucle.
Need 8-12 hours of nitrate free to dec. nitrate intolerance.
CI - DO NOT take with PDEi
CCB tx MOA, special, uses
- Dec. HR - verpamil has negative ionotropic effect.
Ranolazine inhibits inward Na during repol and dec. intracellular Ca
What is variant (prinzmetal) angina?
Transient ST elevation with spasms of coronary artery. Chest pain at rest. Relieved by nitro. Rx: DHP CCB (amlodipine)
Lipid profile goals for adults with prior events.
LDL-C less than 70mg/dl
HDL-C greater than 60mg/dl
TG high is 150mg/dl
Pharm tx of CAD/angina
Statins for hyperlipidemia.