15. Acute Coronary Syndrome

Question 1

Results from disruption of a plaque with subsequent platelet aggregation and formation of an intracoronary thrombus (Jarzembowski lecture)

Answer 1

Acute Coronary Syndromes

Question 2

Form of ACS that results depends on

Answer 2

the degree of coronary obstruction and associated ischemia

Question 3

Following are examples of: – Unstable angina (UA) – Non-ST-Elevation Myocardial Infarction (NSTEMI)

Answer 3

Partially occlusive thrombus:

Question 4

ST-Elevation Myocardial Infarction (STEMI) is:

Answer 4

• Complete obstruction:

Question 5

Most important distinction to make is between ACS are:

Answer 5

causes of ST elevation on the ECG (STEMI) and those that do not (UA, NSTEMI)

Question 6

Severity of symptoms and laboratory findings progress from

Answer 6

UA through NSTEMI to STEMI

Question 7

Presents as an acceleration of ischemic symptoms – Sudden increase in frequency, duration, and/or intensity of ischemic episodes – Episodes of angina at rest – New onset of angina episodes – Not relieved by usual doses of nitroglycerin

Answer 7

Unstable Angina

Question 8

Does nitroglycerin help with unstable angina?

Answer 8

NO

Question 9

Acute Myocardial Infarction 1. Characteristic pain: 2. Sympathetic effect: 3. Parasymp. 4. Inflammatory response

Answer 9

• Severe, persistent, typically substernal • Diaphoresis and Cool and clammy skin *vagal effect ~ Nausea, vomiting, Weakness • Mild fever

Question 10

Cardiac findings in Acute MI

Answer 10

• S4(and S3if systolic dysfunction present) gallop • Dyskinetic bulge (in anterior wall MI) • Systolic murmur (if mitral regurgitation or VSD)

Question 11

Where may these findings be present? • Pulmonary rales (if heart failure present) • Jugular venous distention (if heart failure or right ventricular MI)

Answer 11

In acute MI

Question 12

How do you make diagnosis and distinction among ACS?

Answer 12

– Presenting symptoms – Acute ECG abnormalities – Detection of specific biomarkers of myocardial necrosis

Question 13

ECG abnormalities in Non-STEMI

Answer 13

ST segment depression and/or T wave inversions • May be transient and correlate with chest pain (UA) or persist (NSTEMI)

Question 14

Evolution of ECG in STEMI

Answer 14

Initial ST segment elevation, followed over the
course of hours by inversion of the T wave and
Q wave development

Question 15

Necrosis of myocardial tissue causes
disruption of the sarcolemma and the
release of intracellular molecules into the
bloodstream; we see this rise above threshold in:

Answer 15

NSTEMI and STEMI

Question 16

Cardiac troponins (cTn)
Rise at:

Peak at:

Answer 16

– Assays for cTnI and cTnT detect cardiac
forms and provide a specific measure of
cardiac injury
– Begin to rise at 3-4 h
– Peak 18-36 h

Question 17

Serum marker: Creatine Kinase (CK)

Rise at:

Peak at:

Answer 17

– CK-MB isozyme localized mainly in the
heart
– Begins to rise at 3-8 h
– Peaks at 24 h

Question 18

Typical symptoms of unstable angina

Answer 18

Crescendo, rest,
or new-onset
severe angina

Question 19

When do we see elevated serum biomarkers

Answer 19

in nonSTEMI and STEMI

NOT unstable angina

Question 20

What do we expect to see on ECG for unstable angina?

Answer 20

ST depression and/or T wave inversion

Question 21

Prolonged “crushing” chest pain,
more severe and wider radiation
than usual angina

Answer 21

Symptoms for NonSTEMI and STEMI

Question 22

What do we see on ECG for

nonSTEMI

STEMI

Answer 22

ST depression and/or T wave inversion

ST elevation (and Q waves later)

Question 23

What are requirements of ACS tx?

Answer 23

Requires rapid initiation of therapy to limit
myocardial damage and minimize complications
• Therapy must:
– Address the intracoronary thrombus
– Provide anti-ischemic measures to restore the oxygen supply/demand balance

Question 24

What is the difference in approach to tx STEMI compared to UA/NSTEMI?

Answer 24

– Patients with STEMI typically have total coronary
occlusion and benefit from immediate reperfusion
therapies whereas patients with NSTEMI do not

Question 25

Big list of complications from MI

Answer 25

Recurrent ischemia (angina)
• Arrhythmias
– Ventricular fibrillation, supraventricular arrhythmias,
conduction blocks
• Myocardial dysfunction
– Congestive heart failure, cardiogenic shock
• Mechanical complications
– Papillary muscle rupture, free wall rupture, ventricular
septal rupture, ventricular aneurysm
• Pericarditis
• Thromboembolism

Question 26

Most important predictor of post-MI outcome is the

Question 27

Standard post-discharge therapy after STEMI

Answer 27

– Aspirin
– b blocker
– HMG-CoA reductase inhibitor
– ACE inhibitor (if LV dysfunction)

Question 28

High risk of sudden cardiac death if LV ejection
fraction is _____

Answer 28

< 30%

****Prophylactic implantation of implantable cardiofibrillator

Question 29

What anti ischemic therapies shoud be used after STEMI/NSTEMI

Answer 29

B-blockers

nitrates

Ca+ channel blockers