Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
87 Cards in this Set
- Front
- Back
|
What are the 5 steps in the pathogenesis of an acute MI?
|
1. Atherosclerotic plaque forms
2. Plaque fissures/ruptures 3. Clotting cascade/platelet aggregn 4. Decreased myocardial perfusion 5. Ischemic infarct in muscle tissue |
|
|
What is the classic presentation of an acute MI?
|
ANGINA!
|
|
|
What are 3 symptoms commonly associated with an MI?
|
-Shortness of breath
-Nausea -Diaphoresis |
|
|
What are some atypical signs/sx of acute MI?
|
-SOB/exertional dyspnea
-Generalized weakness (70% women) -Fatigue -Pleuritic chest pain -Confusion |
|
|
What are 7 Risk factors for acute MI?
|
-Age >55
-Family hx of CAD <55 -Personal history of CAD -Diabetes, HTN, Hypercholesterolemia -Tobacco use |
|
|
What does chronobiology refer to?
|
The risk factor of 3-5AM, when cortisol surges - most likely time to have an acute MI
|
|
|
What is the CLASSIC ECG finding in an acute MI?
|
STEMI - ST elevation in 2 or more contiguous leads
-Q waves also often develop |
|
|
What are some NON-ST elevation MI findings on EKG?
|
-Normal EKG (rare)
-ST depression -T wave inversion -New left BBB |
|
|
Why does the ST segment become elevated in acute MI?
|
Bc there is delayed repolarization due to slowed conduction thru the infarcted tissue
|
|
|
How can you tell when ST segment elevation is NOT an acute MI?
|
Lack of reciprocal changes
|
|
|
Why should we see reciprocal changes in an acute MI ecg?
|
Bc the abnormal conduction in the infarcted areas further disrupts conduction in healthy tissue too
|
|
|
What are 3 other things that can cause ST elevation?
|
-Pericarditis
-LV Hypertrophy -Benign early repolarization |
|
|
What 2 cardiac enzymes are used in diagnosing acute MI?
|
-Creatinine kinase MB
-Troponin I |
|
|
How long does it take for CK MB to rise?
|
4-8 hrs
|
|
|
When does Troponin I elevate relative to CKMB?
|
Sooner, and stays elevated longer too
|
|
|
What 4 meds should be administered immediately if an AMI is suspected?
|
-Aspirin
-Betablockers -Nitrates -Heparin |
|
|
What else should you assess if an AMI is suspected?
|
Reperfusion eligibility
-PTCA or thrombolytics |
|
|
What EKG leads will show ST elevation in a LATERAL wall MI?
|
I, aVL, V5/V6
|
|
|
What EKG leads will show ST elevation in an Inferior wall MI?
|
II, III, aVf
|
|
|
What EKG leads will show ST elevation in an Anterior wall MI?
|
V1-V4
|
|
|
What EKG leads will show ST elevation in a Posterior wall MI?
|
V8/v9
|
|
|
What EKG leads will show ST elevation in a Right Ventricular wall MI?
|
V3R/V4R
|
|
|
So what artery is occluded usually in isolated lateral wall AMI?
|
Circumflex artery
|
|
|
What artery occlusion will cause an inferior wall MI?
|
RCA
|
|
|
What artery occlusion will cause an anterior wall AMI?
|
Proximal LAD
|
|
|
In a Lateral wall MI, what EKG leads will show ST elevation again?
|
I, aVL, V5, V6
|
|
|
What leads will show reciprocal ST depression in a lateral wall AMI?
|
II, III, and aVf (the inferior leads)
|
|
|
What leads will show an inferior wall MI ST elevation and reciprocal depression?
|
2, 3, aVf - elevation
I, aVL, and anterior V1-V4 - depression |
|
|
What artery occlusion is usually the cause of inferior wall AMI?
|
RCA
|
|
|
What should you NOT give for a Right Ventricle infarct? Why?
|
Nitroglycerin - will cause a dramatic BP drop!
|
|
|
What are 5 meds that you can save a life with in AMI?
|
-Aspirin
-B-blockers -Heparin -tPA -ACE-inhibitors |
|
|
What EKG should be obtained in all inferior wall MI's? why?
|
Right ventricular MI - V3R/V4R are the most sensitive and specific for an RV MI
|
|
|
In what leads will you see ST elevation and reciprocal depression in an ANTERIOR wall MI?
|
Elev - V1-V4
Depr - Inferior leads II, III, aVf |
|
|
What artery occlusion causes an anterior wall MI?
|
LAD
|
|
|
What degree of dysfunction often results from LAD occlusion and anterior wall MI?
|
More Left Ventricular dysfunction
|
|
|
So what condition is more often seen in anterior wall MI?
|
Cardiogenic shock due to the LV disruption
|
|
|
What type of AMI would you want to give fluid? nitrates?
|
Right side - Fluid
Left side - nitrates |
|
|
Why don't you give nitrates for a RV MI?
|
Bc the right heart is unable to pump blood into the lungs, so blood pools on the venous side of circulation; nitrates are vasodilators and would increase the pooling; give fluid to increase preload
|
|
|
Why don't you give fluid for a LV MI?
|
Because the left side can't pump the fluid out, thus is fills up the lungs and causes pulmonary edema
|
|
|
What leads show ST elevation and depression in a POSTERIOR wall MI? What else is seen in a posterior MI?
|
ST Elev - V8/V9
Depr - V1-V3 ALSO - large R wave in V1/V2 |
|
|
What is the first step in initial management of AMI?
|
Oxygen
|
|
|
What does oxygen do?
|
-Limits ischemic injury/size of infarct
-Decreases ST elevation -Limits hypoxia in CHF patients |
|
|
What should you do if just supplemental oxygen fails to help, or the patient gets too tired to breathe?
|
Intubate
|
|
|
What's the 2nd step in initial AMI management?
|
IV Access - multiple lines
|
|
|
What can you do with a central line?
|
Pace or Swan
|
|
|
What type of meds are best administered through a central access?
|
Pressors
|
|
|
What can happen if you give pressors through a peripheral line?
|
Tissue necrosis dt extravasation
|
|
|
What are the 4 cardiac meds you should adminiser through the IV line?
|
-Aspirin
-Nitrates/nitroglycerin -Beta-blockers -Morphine for pain |
|
|
What does nitroglycerin do?
|
-Dilates coronary vessels
-Decreases preload |
|
|
Who is nitroglycerin especially
-good for -bad for |
Good - CHF patients (decr preload)
Bad - RV MI - causes venous pooling |
|
|
So in what 2 cases should you NOT give nitroglycerin?
|
-RV MI
-Systolic BP <100 |
|
|
What are 3 ways Nitroglycerin can be administered?
|
-Transcutaneous
-Sublingual -IV |
|
|
When should you NOT give nitroglycerin transcutaneously?
|
Acute setting - takes too long
|
|
|
How is Nitroglycerin dosed sublingually?
|
.4mg every 5 min for pain up to 3X total
|
|
|
How is Nitroglycerin given IV? Why is this better than sublingual?
|
Start at 10-20 mcg/min, tritate up for pain as BP allows - better control, short half life, smaller doses
|
|
|
When is Morphine indicated in an AMI?
|
When pain is unresponsive to nitrates
|
|
|
How does Morphine help in AMI?
|
-Reduces preload
-Reduces anxiety -Reduces Myocardial O2 requirements |
|
|
What are 2 adverse effects Morphine can cause?
|
-Hypotension
-Bronchospasm |
|
|
How does Aspirin work in treating AMI?
|
Inhibits platelet aggregation by inhibiting TxA2, reduces coronary RE-occlusion after TPA
|
|
|
How should aspirin be dosed/given in an AMI situation?
|
324 mg (4 baby aspirins) CHEWED!
|
|
|
How do B-blockers work in treating AMI?
|
-Decrease ventricular dysrythmias
-Reduce infarct size |
|
|
In what 3 conditions should you AVOID beta blockers?
|
-CHF
-COPD -Heart Block |
|
|
How do you determine the immediate treatment indicated for an AMI?
|
By looking at the ECG
-ST depression or dynamic TW inversion -ST elevation or new LBBB |
|
|
What immediate treatment should begin for patients with ST depression or dynamic TW inversion?
|
-Begin Heparin
-Stable -> CCU -Unstable -> cath lab |
|
|
What immediate treatment should begin for patients with ST elevation or new LBBB ?
|
-Begin heparin, prepare for cath lab
-Is Time of onset <12 hrs? |
|
|
What patients should receive heparin?
|
-All patients undergoing PCI
-All patients getting fibrinolytic therapy |
|
|
How much is mortality reduced when heparin is used alone?
|
17%
|
|
|
What are the 3 eligibility criteria for thrombolytic therapy in AMI?
|
-Ischemic type pain (angina)
-ST seg elevation >1mm in 2 contiguous leads -Onset <12 hrs prior |
|
|
What are the 2 types of reperfusion strategies that can be used for AMI?
|
-Fibrinolytic therapy
-Direct Coronary angioplasty (if cath lab team available) |
|
|
When does Fibrinolytic therapy have the greatest benefit?
|
When started w/in 3 hrs of pain onset
|
|
|
How helpful is fibrinolysis when given in the 1st HOUR?
|
50% reduction!
|
|
|
For what type of AMI is fibrinolysis less effective?
|
Inferior MI - unless it's a RV infarct
|
|
|
What is the RISK of giving fibrinolytic therapy?
|
Bleeding - esp ICH
|
|
|
What are 3 factors that increase a patient's risk of bleeding on fibrinolytic TPA?
|
-Age >65
Low body weight Initial HTN 180/110 |
|
|
What is a better treatment for those patients with risk factors for bleeding on TPA?
|
Angioplasty
|
|
|
How do Angioplasty and TPA compare?
|
Angioplasty is superior
|
|
|
In what % of patients is Angioplasty successful?
|
90%
|
|
|
Why is Angioplasty superior to TPA?
|
-Higher rates of coronary bloodflow
-Lower rates of reocclusion |
|
|
What is the risk of angioplasty?
|
Dissecting the coronary artery being cathed
|
|
|
What is the most common complication of AMI?
|
Arrythmia - usually ventricular
|
|
|
How should ventricular arrythmias be treated?
|
With ACLS algorithms
|
|
|
What is NOT indicated for post-MI arrythmias?
|
Prophylactic lidocaine - no shown benefits
|
|
|
What other complication are post-MI patients at risk for?
|
Cardiogenic shock
|
|
|
What are some signs that a patient is in cardiogenic shock?
|
-Lung fluid
-Hypotension -Hypoperfusion |
|
|
What is the treatment for cardiogenic shock?
|
-Diuretics
-Pressors -Intraaortic balloon pump |
|
|
What do pressors do? What 2, and when?
|
Increase inotropy of the heart
-Dopamine - normo/mildly hypotensive -Dobutamine - severely hypotensive |
|
|
What should be started along with the treatment for cardiogenic shock?
|
Invasive monitoring!
|
