DSA: Clinical Approach to Stable Angina, Acute Coronary Syndrome, Aortic Dissection (Selby) Flashcards
What is Stable Angina?
- chest/pain pressure for at least 2 months that is worse with exertion or emotional stress
- has not worsened during that time
What are the 3 classifications of Acute Coronary Syndrome?
Unstable Angina
- new onset angina, angina at rest, inc. in freq/sever.
- normal cardiac enzymes, possible ST seg. depress
NSTEMI
- ST segment depression or T-wave inversions
- ABNORMAL cardiac enzymes
STEMI
- ST segment ELEVATION; abnormal cardiac enzyme
- new LBBB or posterior MI
What lipoproteins are seen as risk factors for Coronary Artery Disease (CAD)?
- low HDL < 40 mg/dL and HIGH LDL
- high non-HDL
What are 3 common NON-traditional risk factors for CAD development? (C/P/IS)
- Chronic Kidney Disease
- Proteinuria
- Inflammatory States (HIV, Rheumatoid Arteritis, etc)
What is the classical presentation of Acute Coronary Syndrome?
What patient populations do painless AMIs occur in? (3)
CP: chest pain, dyspnea, nausea/vomiting, fatigue, diaphoresis (sweating)
- silent AMIs more common in ELDERLY, FEMALE, and DIABETIC patients
- be suspicious of atypical presentations
What are the 3 classic components of Angina Pectoris as defined by the Diamond-Forrester Criteria?
What are the 3 classifications of Angina based on this criteria?
CC:
- substernal chest pain or discomfort
- provoked by exertion or emotional stress
- relieved by rest and nitroglycerin
Classifications:
- Typical Angina = has all 3 components
- Atypical Angina = has 2 of 3 components
- Non-Angina CP = has 1 or less of these components
How is Stable Angina (CAD) diagnosed? (4)
What are 3 examples of Cardiac Stress tests?
- use pt. presentation, resting ECG (look for ST segment changes, T-waves, LBBB, post. MI), Cardiac Stress Testing, and Invasive Coronary Angiography
Cardiac Stress Tests: Exercise ECG, Exercise/Dobutamine ECHO, and MPI (use vasodilators to stress the heart)
Who should receive a Cardiac Stress Test and what happens when pts. findings are positive?
- use stress tests for pts. with intermediate pretest probability of CAD (10-90% or 25-75%)
- patients with positive stress tests should proceed to invasive coronary angiography
What is the difference between Exercise and Pharmacological Stress ECGs?
What do Stress ECHOs and Stress MPIs look for?
Exercise: performed on treadmill
Pharm:
- vasodilators: dilate coronary arteries (less blood flow)
- dobutamine: inc. oxygen demand (inc. HR/contract.)
ECHO: regional wall motion abnormalities or LV dilation
MPI: perfusion defects during rest and stress
- use IV radioisotope (technetium/thallium)
When can Stress ECG tests NOT be used?
- cannot be used when patients already have baseline ECG abnormalities
How is Coronary Angiography performed?
- catheter is inserted into femoral artery and snaked up to the coronary arteries, where a dye is injected allowing X-Ray imaging to visualize stenosis
- usually do not treat unless stenosis is > 70% (significant stenosis)
How is Acute Coronary Syndrome (CAD) diagnosed? (3)
What are the criteria for diagnosing STEMI vs NSTEMI looking at an ECG?
- resting ECG, cardiac biomarkers, invasive coronary angiography
STEMI: ST segment elev. >2 mm in continuous leads or new LBBB (cannot diagnose if known LBBB already)
NSTEMI: new ST depression >0.5 mm in two contiguous leads or T-wave inversion > 1mm in two contiguous leads with R/S ration >1
What causes a STEMI and NSTEMI to develop?
What is the difference between Type 1 and Type 2 variants?
STEMI: from COMPLETE occlusion of blood flow
NSTEMI: from partial occlusion of blood flow or in presence of complete occlusion w/collateral circulation
Type 1: infact. due to coronary atherothrombosis
Type 2: infact. due to supply-demand mismatch not the result of atherothrombosis
How is Stable Angina Treated? (LM/A/S/AAD)
What drugs are used for Chronic (4) vs Acute angina?
- lifestyle modifications, aspirin, statin, anti-anginal drugs
Chronic: B-blockers (1st line), CCBs, nitrates (long-acting), and ranolazine
- CCB/nitrates can be used with B-blockers
- Ranolazine for refractory angina
Acute: nitrates (short-acting)
What are 3 indications for the use of Coronary Artery Bypass Grafting (CABG)?
What treatment should be considered if CABG or PCI is contraindicated?
- 3 vessels with stenosis > 70%
- left main disease
- left ventricular dysfunction
- either CABG or PCI w/stenting used if coronary anatomy is suitable; if not suitable –> use externally enhanced counterpulsation (put on LE and inflated during diastole) = EECP therapy
Treatment of Acute Coronary Syndrome
What is the “MONA” mnemonic and what drugs are typically given to these patients? (A/P/H/E)
What are 3 drugs shown to improve mortality in Myocardial Infarction? (A/B/A)
MONA = initial management of all ACS patients
- morphine, oxygen, nitrates, aspirin
Drugs: Dual Antiplatelet Therapy (aspirin and P2Y12 inhibitors) and Anticoags (unfractionated heparin and SubQ enoxaparin)
- aspirin, B-blockers, ACE inhibitors
How are STEMI patients managed in a PCI capable hospital vs a non-PCI capable hospital?
- always initiate therapy w/aspirin, B-blockers, nitrates, heparin
Capable: administer P2Y12 and perform PCI in < 90 mins; long-term medical therapy after
Non-Capable:
- transfer to PCI (if possible) within < 120 minutes
- no transfer? –> start thrombolytics < 30 minutes, then transfer to PCI capable hospital
How are Unstable Angina and NSTEMI patients managed? (A/B/N/S)
- initiate aspirin, B-blockers, nitrates, statin
- use TIMI (predicts risk of 14 day death, recurrent MI, or urgent revascularization)
High Risk (TIMI 5-7): early invasive strat (< 24 hrs) Mid Risk (TIMI 3-4): delayed invasive (25-72 hrs) Low Risk (TIMI 0-2): ischemia-guided therapy
What ECG leads and coronary arteries are associated with Myocardial Infarcts at the:
- Inferior Wall
- Septal Wall
- Anterior Wall
- Lateral Wall
- Posterior Wall
- leads II, III, aVF (Right Coronary Artery)
- leads V1-V2 (Left Anterior Descending Artery)
- leads V2-V4 (Left Anterior Descending Artery)
- leads V5/V6 or I/aVL (Left Circumflex Artery)
- tall R waves and ST depression in V1-V3
- 70% originate from the RCA
What is Dressler’s Syndrome?
- postmyocardial infarction syndrome that manifests as PERICARDITIS
- immunologically based syndrome typically occurring within weeks to months after an MI
How are Thoracic Aortic Dissections classified? (2)
Stanford: Type A and Type B (FOCUS ON THIS ONE)
- A = involve ascending aorta (67%)
- B = arise AFTER the Left Subclavian Artery (33%)
DuBakey: Types 1, 2, and 3
- 1: involves ascending and descending aorta
- 2: involves ascending aorta only
- 3: involves descending aorta only
What are 4 risk factors for Aortic Dissection in younger patients? (C/S/C/T)
- Connective Tissue Disorders (MARFAN)
- Syphilis
- Cocaine or meth use
- Trauma (fall or car accident)
- also large arteritis and bicuspid aortic valve (genetic)
What is the classic presentation of a patient suffering from Aortic Dissection?
How does Aortic Dissection affect the pts. Renal, Neuro, and GI systems?
CP: sudden onset chest pain (“tearing” or “ripping” that radiates to the back) and hypertension
- pulse deficits between limbs (asymm. btwn arms)
Renal: acute renal failure
Neuro: Horner’s Syndrome (droopy eyelid, no sweat)
GI: bleeding from aortoenteric fistula; ischemia
What are 4 ways that Aortic Dissection can be diagnosed?
- ECG/cardiac biomarkers (rule out MI)
- Chest X-Ray (wide mediastinum)
- CT ANGIOGRAPHY (most common method)
- Transesophageal ECHO (hemodynamically unstable)
- can see false lumen and true lumen
What is the medical management of Aortic Dissection? (AIT)
What 3 drugs are commonly used? (B/V/O)
- Acute Impulse Therapy to lower HR and diminish force of LV ejection
- *Goal is BP < 120 mmHg and HR < 60 BPM**
- first line therapy: B-blockers (labetalol/esmolol)
- can add vasodilators (nicardipine/nitroprusside)
- Opiates for PAIN
How should Type A and Type B Aortic Dissections be managed?
Type A: have a HIGHER mortality
- open surgery with synthetic graft
Type B: either medical or endovascular treatment
- Uncomplicated = medical treatment
- Complicated = endovascular (STENTING)
