ACS - NSTEMI

Question 1

Caused by an IMBALANCE between myocardial oxygen supply and demand resulting from one or more of the following 3 processes –> coronary arterial thrombosis

1. plaque fissure w/ inflammation - inflammatory response reflected by an increased activity of effector T cells as part of an adaptive immunity dysregulation
2. plaque fissure w/o inflammation
3. plaque erosion - (+) in at least ⅓ of ACS; recognized w/ increasing frequency

Answer 1

NSTEMI

Question 2

Characteristic of VULNERABLE PLAQUE responsible for ACS

Answer 2

LIPID RICH CORE with a THIN fibrous cap

coronary angiography - ECCENTRIC stenosis with SCALLOPED or overhanging edges and a narrow neck

Question 3

HEART

Answer 3

History
ECG
Age
Risk Factors
Troponin

Figure 274-3

Question 4

TIMI Risk Score

Answer 4

Age >65
Known CAD >50% stenosis
ST deviation >0.5 mm on ECG
⬆️cardiac markers
>2 original episodes in prior 24 h
prior angina
>3 CAD risk factors

Question 5

Characteristic chest pain of NSTEMI

Answer 5

SEVERE CHEST DISCOMFORT and has at least 1 of 3 features:

• occurrence at rest (or with minimal exertion), lasting >10 min
• relatively recent onset (i.e., within the prior 2 weeks)
• CRESCENDO pattern - distinctly more severe, prolonged, or frequent than previous episodes

Question 6

VASODILATORS with peripheral and coronary vascular effects

↓ preload (by venodilation) and afterload (arterial dilation)

Answer 6

NITRATES

Question 7

↓ HR, contractility and BP –> MVO2

Answer 7

Beta Blockers

target HR - 50-60

Question 8

Contraindications of Beta blockers

Answer 8

presence of ACUTE or SEVERE heart failure

LOW cardiac output

PR interval ≥ 0.24 s (high degree AV block)

HYPOtension

Question 9

Recommended for patients who have persistent symptoms or ECG signs of ischemia AFTER treatment with FULL DOSE NITRATES and BETA BLOCKERS and in patients with contraindications to either class of these agents

Answer 9

Calcium Channel Blockers

Question 10

Shown to ↓ periprocedural MI and recurrences of ACS

Answer 10

STATINS (HIGH DOSE)

Question 11

For patients who do not have an adequate response to maximally tolerated statin (i.e., <50% ↓ in LDL-C from untreated baseline or LDL-C on treatment >70 mg/dL)

Answer 11

EZETIMIBE

shown to ↓ future cardiovascular events

10 mg daily to reduce further the LDL-C

Question 12

Cyclooxygenase inhibitor –> blocks synthesis and release of thromboxane A2 (platelet activator) –> ⬇️ platelet aggregation and thrombus formation

Answer 12

Aspirin

INITIAL TREATMENT

Question 13

Thienopyridine - an inactive prodrug that is converted into an active metabolite that causes IRREVERSIBLE blockade of the platelet P2Y12 receptor

Answer 13

Clopidogrel

loading dose - 600 or 300 mg

maintenance dose - 75 mg daily

Question 14

Thienopyridine - achieves a more rapid onset and higher level of platelet inhibition than clopidogrel

Answer 14

Prasugrel

approved for ACS patients following angiography when PCI is planned

Question 15

Potent, REVERSIBLE platelet P2Y12 inhibitor

↓ the risk of cardiovascular death, total mortality or MI compared to clopidogrel across a broad-spectrum patient with ACS

Answer 15

Ticagrelor

Question 16

Should be considered in patients with NSTE-ACS who DEVELOP a NEW coronary event while receiving clopidogrel and aspirin

Answer 16

P2Y 12 blockers (PRASUGREL or TICAGRELOR)

Question 17

Anticoagulants

Answer 17

UFH - mainstay of therapy
LMWH - Enoxaparin
DTI - Bivalirudin
Indirect Factor XA inhibitor - Fondaparinux

Question 18

Carried out within ~48 h of presentation, followed by coronary revascularization (PCI or coronary artery bypass grafting) depending on the coronary anatomy

Answer 18

Coronary arteriography

Question 19

VERY HIGH –> VERY HIGH

Answer 19

immediate transfer to PCI center
intermediate invasive (<2 hr)

Question 20

HIGH –> HIGH

Answer 20

same day transfer
early invasive <24 hr

Question 21

INTERMEDIATE –> INTERMEDIATE

Answer 21

transfer
invasive <72 hr

Question 22

LOW –> LOW

Answer 22

transfer optional
invasive <72 hr
non invasive testing if appropriate

Question 23

LONG TERM MANAGEMENT

Answer 23

beta blockers
intensive lipid lowering therapies - LDL<55
ACE (-) or ARBs
SGLT2 or GLP1 agonists - DM Type 2
antiplatelet therapy

Question 24

Patients at HIGH ISCHEMIC RISK (e.g., those with prior MI, diabetes mellitus, coronary vein graft, heart failure) who are also at low risk of bleeding and not on an anticoagulant

Answer 24

continuation of DAPT to 3 years has been shown to be beneficial

Question 25

**Syndrome of severe ischemic pain that usually occurs at rest** Associated with **ST segment elevation**

Answer 25

**PRINZMETAL ANGINA** ## Footnote minority of patients have a **generalized vasospastic disorder associated with migraine and/or Raynaud’s phenomenon**

Question 26

**Pathophysiology of Prinzmetal Angina**

Answer 26

**FOCAL SPASM of an EPICARDIAL CORONARY ARTERY with resultant transmural ischemia and abnormalities in left ventricular function -- acute MI, ventricular tachycardia or fibrillation, and sudden cardiac death**

Question 27

**Diagnostic hallmark of Prinzmetal Angina**

Answer 27

**coronary angiography - TRANSIENT coronary spasm**

Question 28

**The main therapeutic agents of PVA**

Answer 28

**NITRATES and CCB**

Question 29

**Patients with PVA who have had ischemia-associated ventricular fibrillation despite maximal medical therapy should receive**

Answer 29

**implantable cardioverter-defibrillator (ICD)**

Question 30

**Mechanism contributing to the pathophysiology of NSTE-ACS**

Answer 30

**Coronary plaque fissure with ⬆️ T cell activity causing obstructive thrombosis**

Question 31

**Elevations of cTn >99th percentile WITHOUT a clear clinical history of ECG features of acute myocardial ischemia**

Answer 31

**Myocardial INJURY** Table 274-2

Question 32

Have been used to **provoke focal coronary stenosis** on angiography or to **provoke rest angina with ST-segment elevation to establish the diagnosis of Prinzmetal Angina**

Answer 32

**hyperventilation and intracoronary acetylcholine**