Acute Coronary Syndromes (STEMI, NSTE-ACS)

Question 1

Unstable angina

Answer 1

Normal cardiac biomarkers

May have nonspecific ECG changes, ST-segment depression, or T-wave inversion

Question 2

NSTEMI

Answer 2

ST-segment elevation of ≥1 mm in ≥2 contiguous limb or chest leads, although ST-segment elevation in leads V2 and V3 must be ≥2 mm in men and ≥1.5 mm in women

ST-elevation equivalents include new LBBB or posterior MI (tall R waves and ST depressions in V1-V4)

Question 3

Immediate indications for angiography in unstable angina/NSTEMI

Answer 3

hemodynamic instability
HF
recurrent rest angina despite therapy
new or worsening MR murmur
sustained VT

Question 4

ST-segment elevation causes

Answer 4

acute pericarditis, LV aneurysm, stress (takotsubo) cardiomyopathy, coronary vasospasm, acute stroke, or normal variant

Question 5

Key concepts

Answer 5

if ischemic symptoms less than 12 hours, PCI should be performed to improve survival.

Question 6

Key concepts

Answer 6

If cardiogenic shock or hemodynamic instability, PCI or CABG (when PCI is not feasible) is indicated to improve survival, irrespective of the time from MI onset.

Question 7

key concepts

Answer 7

PCI should be performed as soon as possible, with first medical contact to PCI time ≤90 minutes in a PCI-capable hospital and ≤120 minutes if transferred from a non–PCI-capable hospital to a PCI-capable hospital.

Question 8

Other indications for PCI

Answer 8

failure of thrombolytic therapy

new HF or cardiogenic shock

Question 9

Aspirin indications

Answer 9

ASAP for all patients with ACS
Continue indefinitely as secondary prevention

Question 10

P2Y12 inhibitor indications (clopidogrel, ticagrelor, or prasugrel in patients with ACS treated with PCI)

Answer 10

ASAP for all patients with ACS

Prasugrel contraindicated in patients age ≥75 years or history of CVA/TIA

Continue for at least 1 year following MI in most patients

Question 11

β-Blockers indications (metoprolol, carvedilol)

Answer 11

Administer for ACS within 24 hours

Continue indefinitely as secondary prevention

Question 12

Anticoagulant indications (UFH, LMWH, fondaparinux)

Answer 12

ASAP for definite or likely ACS. Choice depends on reperfusion strategy. Any can be used with thrombolytic therapy. UFH is preferred for PCI, and fondaparinux should be avoided.

Question 13

ACE inhibitors indications

Answer 13

Administer within 24 hours

Continue indefinitely in patients with reduced LVEF or clinical HF, diabetes, hypertension, or CKD

Question 14

ARB indications

Answer 14

Administer if intolerant of ACE inhibitor

Question 15

Nitroglycerin indications

Answer 15

Administer in presence of ongoing chest pain or HF

Question 16

Statin indications

Answer 16

Administer high-intensity statin early, even in patients with low LDL levels

Continue indefinitely as secondary prevention

Question 17

Eplerenone indications

Answer 17

Administer 3 to 14 days after MI if LVEF ≤40% and clinical HF or diabetes

Question 18

Recommendations for temporary pacing acute MI

Answer 18

symptomatic bradycardia (including complete heart block)
alternating LBBB and RBBB
new or indeterminate-age bifascicular block with first-degree AV block

Question 19

Right ventricular infarction

Answer 19

may present with hypotension or may develop hypotension following the administration of nitroglycerin or morphine. Look for JVD with clear lungs, hypotension, and tachycardia. The most predictive ECG finding is ST-segment elevation on right-sided ECG lead V4R. Treat with IV fluids.

Question 20

Mechanical complications (VSD, papillary muscle rupture, and LV free wall rupture)

Answer 20

may occur 2 to 7 days after an MI. Emergency echocardiography -initial diagnostic test.

VSD or papillary muscle rupture -> abrupt pulmonary edema or hypotension and a loud holosystolic murmur and thrill.

LV free wall rupture causes sudden hypotension or cardiac death associated with pulseless electrical activity.

Patients with papillary muscle rupture and VSD should be stabilized with an intra-aortic balloon pump, afterload reduction with sodium nitroprusside, and diuretics followed by emergency surgical intervention.

Question 21

Cardiogenic shock

Answer 21

Emergency revascularization supported by intra-aortic balloon pump and LVAD may be necessary.

Question 22

Postinfarction angina

Answer 22

Cardiac catheterization is indicated.

Question 23

ICDs indications in post-MI patients

Answer 23

> 40 days since MI or >3 months since PCI or CABG
LVEF ≤35% and NYHA functional class II or III or LVEF ≤30% and NYHA functional class I