1. Acute Coronary Syndrome & Acute Myocardial Infarction
NURS 241
Chapter 34 (p.760)

2. Progression of Atherosclerosis
Fatty Streak
Earliest Lesions (Age 15 and greater)
Reversible with LDL lowering therapies
Fibrous Plaque (Beginning of progressive endothelial changes)
LDLs thicken arterial wall (Age 30 and greater)
Inability of endothelium to normally repair self, fibrous plagues narrow artery walls
Complicated Lesion
Final, most dangerous stage
Plaque instability/ulceration/rupture, platelets adhere and form thrombi, further narrowing of artery lumen

3. Collateral Circulation
Factors affecting development:
-Angiogenesis (genetic predisposition to develop new vessels)
-Presence of CHRONIC ischemia
Rapid-onset CAD or coronary spasm patients…
Not enough time for collateral development…
= More severe ischemia and/or infarction

4. CAD Risk Factors Review
Non-Modifiable
Modifiable
Age
Gender
-Onset typically 10 yrs. earlier in men
-Kills more women onset, more co-morbidities, atypical s/s)
Ethnicity
Family History
-Familial Hypercholesterolemia
Hyperlipidemia (sometimes somewhat non-modifiable)
HTN
Tobacco use
Physical inactivity
Obesity
Diabetes
Metabolic Syndrome
Psychologic stress*
Elevated homocysteine levels

5. What is Angina?
Chest pain representative of REVERSIBLE myocardial ischemia
Demand for myocardial O2 exceeds supply
Atherosclerotic ischemia- artery 75% or more stenosis/obstruction

6. Types of Angina Chronic Stable -Controlled w/ meds, more predictable
Silent Ischemia
-More common in Diabetics
Nocturnal
Decubitus
Prinzmetal’s
-Coronary spasm (may be no Hx CAD), ST changes
Microvascular
-Abnormal microcirculation, more common in women

7. Rx Therapy for Angina Short-acting nitrates (NTG SL)
Long-acting nitrates (Imdur or NTG paste)
β-adrenergic blockers (carvedilol, metoprolol)
-First choice for chronic stable
Ca Channel Blockers
-Alternative to β-blockers
ACE Inhibitors (Captopril, Vasotec)
-Along with a β-blockers if pt. is high risk for cardiac event
-ARBs (Cozaar) alternate if ACE inhibitors not tolerated

8. What is ACS? Acute Coronary Syndrome
Prolonged ischemia NOT immediately reversible
Encompasses
-Unstable angina
-NSTEMI
-STEMI
Pg. 777 (fig. 34-8)

9. Unstable Angina
New in onset, occurs at rest, or has a worsening pattern
Often unprovoked & unpredictable
Unrelieved by usual Tx modalities (i.e. SL NTG doesn’t work)
MEDICAL EMERGENCY!

10. Acute Myocardial Infarction (AMI)
Sustained ischemia → Irreversible myocardial cell death (aka necrosis)
80-90% AMIs result of thrombus formation
Cardiac cells begin dying 20 minutes after start of ischemia
Subendocardium first to die
If untreated… 4-6hrs until entire thickness of myocardium necrosed

11. Main Coronary Arteries

12. Damage Location RCA occlusion = Inferior wall MI
leads II, III, AVF
LAD occlusion = Anterior wall MI
leads V1-V4
Left Circumflex occlusion = Lateral wall MI
leads I, AVL, V5, V6

13. Where is the STEMI?

14. AMI Clinical Manifestations
Chest Pain- unrelieved by rest, nitrates
Atypical discomfort
-Women = SOB, fatigue
-Elderly = Confusion, SOB, dizziness
SNS stimulation- diaphoretic, pale from vasoconstriction
Initial HTN, Tachycardia eventually drops d/t low CO
N/V- vasovagal reflex or pain response
Fever- inflammatory response

15. Diagnostics for AMI 12 lead EKG* Serum cardiac markers (Troponin)
Coronary Angiogram

16. Immediate Interventions for AMI Patient
Morphine, NTG, ASA, O2 PRN
Emergent percutaneous coronary intervention (PCI)
-Angioplasty
-Stenting (Typically drug-eluting, but may be bare metal)
-Administration of IIb/IIIa inhibitors (ReoPro, Integrilin)
-Placement of IABP PRN
Fibrinolytics (if indicated)
Emergent CABG if indicated

18. Coronary Artery Bypass Graft (CABG)
May be done if multi-vessel disease found during coronary angiogram
MUST be done if dissection of artery occurs in cath lab

19. Intra-Aortic Balloon Pump (IABP)
May be inserted if pt. is developing cardiogenic shock OR
If extensive myocardial damage sustained following ACS
Increases coronary artery perfusion d/t inflation on diastole & Decreases afterload d/t deflation on systole

20. Complications of AMI Dysrhythmias (80% pts.)
-RCA supplies blood to SA/AV node
-Life threatening dysrhythmias most common following anterior wall MI
-Ventricular ectopy from ischemia
-AFib
Cardiogenic shock- may need IABP
(Congestive) Heart Failure
Pericarditis
Ventricular wall aneurysm and/or rupture
Dressler Syndrome- pericarditis, fever, pericardial effusion

21. Medications for the AMI Patient
Nitroglycerin gtt- ↓ preload & afterload, ↑myocardial O2 supply
Morphine- ↓ myocardial O2 consumption, HR, BP, contractility
β-adrenergic Blockers- reduce risk re-infarction & VFib
ACE Inhibitors- prevent or slow development of HF
Antidysrhythmics
Cholesterol-lowering drugs- prevent re-occlusion
Stool Softeners- prevent strain & resultant dysrhythmias