myocardial infarction

Question 1

What is the next step for a pt with reversible myocardial ischemia?

Answer 1

cardiac catheterization- must assess need for percutaneous transluminal coronary angiopalsty or CABG

Question 2

When are enzymes measured in acute MI?

Answer 2

q8 hrs over first 24 hrs- total of 3 troponin measurements

• CK-MB increases 2-12 hrs post-MI peaks, at 12-40 hrs, and is decreasing on days 1-3
• troponins rise fast (2-3 hrs), peak at 6 hrs, but stay high for 7 days

Question 3

what leads show anterior infarct? what is the vessel?

Answer 3

V2, V3, V4

LAD

Question 4

what leads show a septal infarct?

Answer 4

V1, V2, V3

Question 5

what leads show an interior infarct? coronary artery branch?

Answer 5

leads II, III, aVF

this is a posterior descending or marginal infarct

Question 6

What leads show a lateral infarct?

Answer 6

I, aVL, V4, V5, V6; usually LAD or left circumflex

Question 7

What leads show a posterior infarct?

Answer 7

V1, V2. usually there is a comorbid inferior MI due to occlusion of the posterior descending

Question 8

What is the treatment for acute MI?

Answer 8

-IV morphine, supplemental O2, nitroglycerine, ASA, heparin, BB, statin and antiplatelet like clopidogrel or ticagrelor

Question 9

What is the treatment for a STEMI?

Answer 9

• perform PCI (percutaneous coronary intervention) and give a GP IIb/IIIA inhibitor (like abiciximab, tirofiban, epifibatide)
• If PCI not possible in first 12 hrs post-MI, consider tPA or urokinase
• give K to keep >4 and magnesium to keep >2
• If emergent catheterization not performed, perform cardiac catheterization to measure vessel patency and consider PTCA or CABG

Question 10

What should be done for hypotensive pt with STEMI?

Answer 10

-Stop nitroglycerin, give IV fluids, give amiodarone for pts with Vtach

Question 11

What are long term treatments for post-MI pts?

Answer 11

risk reduction including ASA or clopidogrel, BB, ACE-I or ARB, statin, exercise, smoking cessation
consider aldosterone antagonist

Question 12

what are the common complications of MI?

Answer 12

infarct extension, arrhythmias, aneurysm, mural thrombus, pericarditis, dressler syndrome (fever, pericarditis, and incr. ESR seen 2-4 wks post MI)

Question 13

When is risk of ventricular wall rupture greatest?

Answer 13

6-8 days post-MI

Question 14

What medications decrease mortality after MI?

Answer 14

BBs and ACE-Is

Question 15

What are some draw-backs of BBs?

Answer 15

can have negative effects on patients with asthma, COPD, PVD (peripheral vascular disease), DM (can mask hypoglycemia), and depression