Ischemic Heart Disease Flashcards
Exam 2 content
Treatment for Prinzmetal angina?
CCB -> Verapamil
2 most important risk factors for IHD (ischemic heart disease)?
Male and age
what percentage of surgical patients have IHD?
30%
How much of an occlusion does stable angina indicate?
70%
What condition is the most common cause of impaired coronary flow resulting in angina pectoris?
Atherosclerosis
Angina can radiate through what dermatomes?
C8-T4
Stable vs unstable angina?
S - CP that does not change over 2 months
U - angina at rest lasting longer than 10 minutes
Describe the acute and long term trends of a troponin level
Acute: remains elevated for 3-4 hours
Long term: elevated ~2 weeks
What is the relationship between ST depression and angina?
ST depression is usually indicative of subendocardial ischemia. The larger the ST depression the greater the likelihood of significant CAD.
Is a stress test or nuclear stress imaging more sensitive for detection of IHD?
Nuclear stress imaging
What tracers and chemicals are used in nuclear stress imaging?
Tracers: Thallium and technetium
Chemical stressors: atropine, dobutamine, pacing, adenosine and dipyridamole
What does coronary angiography NOT tell us about IHD? What could provide a hint?
The stability of the plaque (old vs new). Presence of collateral circulation
What are Thienopyridines (P2Y inhibitors)
Examples: clopidogrel (Plavix) and prasugrel (Effient)
These inhibit ADP receptor P2Y inhibiting platelet aggregation
Effient is more potent than Plavix and has a higher risk of bleeding
What anti-platelet is a prodrug?
Plavix (clopidogrel)
What affects do platelet glycoprotein IIb/IIIa antagonists do? Name a few…
these inhibit platelet activation, adhesion and aggregation. Abciximab, eptifibatide, tirofiban.
What drugs are nitrates synergistic?
BBs and CCBs
What is a core measure for anesthesia providers r/t to beta blockers? Why?
All patients previously on BB should receive a BB during the case.
BBs are the only drugs that prolong the lifespan of patients with CAD.
What conditions are nitrates contraindicated?
Aortic stenosis and hypertrophic cardiomyopathy
Only drug that prolongs life in CAD?
BBs
Which BBs have bronchospasm concerns?
Propranolol and Nadolol
Advantage of being on an ACE? Cons?
A = prevent remodeling and stabilize electrical activity, reduce myocardial workload/oxygen demand
C = loss of RAAS means they don’t handle hypotension as well
When is revascularization indicated in L main, all other coronaries and EF changes?
L main = 50% occlusion
Other coronaries = 70% occlusion
EF: less than 40%
What are the two interventions we have for coronary revascularization?
PCI and CABG.
What coronary occlusions is a CABG generally preferred over PCI?
L main disease, triple vessel disease or a patient with DM with 2 or more vessel disease
How would you differentiate unstable angina vs a NSTEMI?
12-lead and troponins. 12-lead is +/- with + troponin = NSTEMI
negative 12-lead with negative troponin = unstable angina
What is the criteria to diagnose an MI?
+ troponin, s/sx of ischemia, ECG changes, pathologic Q waves, imaging evidence (wall motion abnormality) or direct identification via angiography
What is the relationship of depth of ST changes to likelihood of ACS?
The greater the degree of depression = the higher chance of significant coronary disease
If an EKG suggests an MI, is an echo required?
No. It can be helpful if they have a BBB or if AMI is uncertain such as suspected aortic dissection.
Contraindications to starting a BB?
Heart failure, low CO state and not at risk of cardiogenic shock
When should thrombolytics be given? Cutoff time?
Within 30 - 60 minutes, and no later than 12 hours
Timeframe to start angioplasty?
Within 90 minutes and within 12 hours of symptom onset
When is PCI preferred over thrombolytics?
Heart failure, pulmonary edema, symptoms present for at least 2-3 hours or when the clot becomes more mature. Also if patient cannot receive systemic thrombolytics.
Treatment for unstable angina?
Bed rest, oxygen, analgesia and BBs. Nitro and CCBs can help if ischemia persists.
Other helpful agents: ASA, plavix, heparin
Thrombolytics = contraindicated
How long is a patient at risk for thrombosis after balloon angioplasty, bare metal/drug eluding stent placement?
Balloon = 2-3 weeks
Bare stent = 12 weeks minimum (longer preferred)
Drug eluding stent = a full year
What are our 2 major concerns with a stent placement?
Thrombosis and increased risk of bleeding
Downside of ASA/Plavix relative to heparin?
No reversal agent, all you can do is give platelets
How long should a patient wait for surgery after angioplasty, bare metal stent, CABG and drug eluding stent placement?
Angio = 2 -4 weeks
Bare = 4 - 12 weeks
CABG = 6 - 12 weeks
Drug = 6 - 12 months
When do you stop an ACE?
24 hours
What is the preferred agent to treat bradycardia in the OR?
Glycopyrrolate > atropine
What other drug do we give with glycopyrrolate?
Neostigmine–> the effects balance each other out
What tool do we use to quantify risk stratification of surgery? What’s considered low risk? Elevated risk?
revised cardiac risk index (RCRI).
Low risk: RCRI</= 1
Elevated: RCRI > 2
Goal for METs?
Greater than 4, which is climbing a flight of stairs or better
Ideal time to wait for surgery after an MI?
Generally greater than 60 days
Hard cardiac stops to the administration of anesthesia?
Unstable angina, decompensated HF, severe valve disease, significant dysrhythmias
Most important goal to achieve if a patient has heart disease when going to the OR? Other factors to try and control?
Must avoid tachycardia. Other goals = prevent HTN, SNS stimulation, arterial hypoxemia and hypotension. Go slow.
What anesthetics are good to use to prevent tachycardia?
Sux, Vec, Roc, cisatracurium, lidocaine, esmolol, fentanyl, remifentanil and Dex
With severely impaired LV function, what would be a good choice of anesthesia for induction?
High dose opioid only
Assuming appropriate anesthetic depth, good drug of choice to treat tachycardia? Brady?
T = esmolol
B = Glyco > atropine
II, III and AVF changes indicate what kind of occlusion?
RCA occlusion
I, AVL indicate changes indicate what kind of occlusion?
Circumflex occlusion
V3-5 indicate changes indicate what kind of occlusion?
LAD occlusion
