Acute Coronary Syndrome

Question 1

Define acute coronary syndrome

Answer 1

symptoms from underlying acute myocardial ischemia

Question 2

Causes of ACS

Answer 2

1) atherosclerotic plaque rupture + thrombus = MOST COMMON
2) coronary embolism
3) congenital
4) coronary trauma/aneurysm
5) cocaine (spasm)
6) incr blood viscosity
7) spotaneous coronary dissection
8) incr myocardial O2 demand

Question 3

partial occlusion

Answer 3

decr blood flow in artery distal to occlusion

decr O2 supply to myocardium

ischemia

Question 4

complete occlusion

Answer 4

no blood flow and O2 to entire myocardium supplied by artery = ischemia

Question 5

Pathophys of ACS

Answer 5

1) inflamm + risk factors incr atherosclerosis
2) dysfunctional endothelium
3) inflamm mediators weaken atherosclerotic fibrous cap
4) if cap bursts, thrombogenic tissue factor released –> platelet aggreg
5) dysfunctional endo + coag + PLT aggreg = coronary thrombosis

Question 6

define STEMI

Answer 6

1) complete coronary vessel occlusion

Question 7

what is a complete coronary vessel occlusion called

Answer 7

STEMI

Question 8

define NSTEMI

Answer 8

partial coronary vessel occlusion with myocardial necrosis

Question 9

what is a partial coronary vessel occlusion with myocardial necrosis

Answer 9

NSTEMI

Question 10

define unstable angina

Answer 10

partial coronary vessel occlusion and ESCALATING SX without myocardial necrosis

don’t need troponin elev

Question 11

what is partial coronary occlusion WIthout MYOCARDIAL NECROSIS

Answer 11

unstable angina

Question 12

define transmural ischemia

Answer 12

spans entire thickness of myocardium assoc with COMPLETE coronary OCCLUSION

ST ELEVATION

Question 13

define subendocardial ischemia

Answer 13

involves innermost layer of myocardium due to PARTIAL coronary occlusion

ST DEPRESSION

Question 14

if ischemia is prolonged, ____

Answer 14

results in myocyte death + tissue necrosis (STEMI or NSTEMI)

Question 15

ecg changes of STEMI and NSTEMI

Answer 15

STEMI = ST elevation

NSTEMI = ST depression

Question 16

___ is very sensitive and specific for myocardium

Answer 16

Cardiac troponin

Question 17

Describe angina

Answer 17

discomfort due to myocadial ischemia

chest pain/pressure/tightness

Question 18

symptoms of angina

Answer 18

1) substernal chest pain/tightness
or
2) left arm pain, SOB, N/V, weakness,

Question 19

Stable angina define

Answer 19

when incr demand for myocardial oxygen in REPRODUCIBLE fashion

Question 20

Unstable angina define

Answer 20

no myocyte death but ischemia is occurring

new onset OR

increased duration, freq, intensity of discomfort with less exertion

or
less provocation/discomfort at rest

Question 21

which of the angina’s is on the spectrum of ACS?

Answer 21

UNSTABLE ANGINA

Question 22

Treatment of ACS (2 golas)

Answer 22

1) relieve ischemia
- open artery or prevent further occlusion
- reduce myocardial O2 demand

2) prevent adverse outcomes

Question 23

how to treat STEMI

Answer 23

1) if artery occluded, open !!!
primary PCI

if >90 min, use fibrinolytics and transfer

if >90 + heme/BP stable, use oral beta blockers/nitrates (reduce LV filling) to decr myocardial O2 demand

Question 24

how to treat NSTEMI/unstable angina

Answer 24

1) artery partially occlude–> give anticoag + anti platelet to STOP PROPAGATION OF CLOT TO BECOME STEMI

reduce myocardial O2 demand using beta blockers, nitrates
or
cath lab for PCI

Question 25

anticoags to use for NSTEMI/unstable angina

Answer 25

1) unfractionated heparin
2) low-molecular weight heparin,
3) fondaparinux

Question 26

antiplatelets to use for NSTEMI/unstable angina

Answer 26

2 platelet AGENTs (1 ASA + EITHER
1) P2Y12 inhibitors (clopidogrel, prasugrel, ticagrelor)

2) GpIIb/IIIa inhibitors

Question 27

how to treat NSTEMI/unstable angina + heme stable

Answer 27

use oral beta blockers or nitrates to decr myocardial O2 demand

Question 28

ST segment

Answer 28

depolarization of ENTIRE VENTRICLE

Question 29

ECG with partial occlusion no infarct

if during sx

Answer 29

ECG may be same as NSTEMI

Question 30

ECG with partial occlusion no infarct

if obtained when no sx (less O2 demand)

Answer 30

ECG look normal

Question 31

Troponin I and T

Answer 31

sensitive and specific for myocardium

rise 3-4 hrs after pain onset

peak at 18-36 hrs

Question 32

Creatine Kinse - MB isoenzyme

Answer 32

not as specific

rise 3-8 hrs after pain onset

Peaks at 24 hrs