Troponin I and T

Question 1

Troponin trend

Answer 1

Elevate at 4 hrs after MI
Peak at 44hrs
Remain elevated for 14 days

Question 2

Initial anti-ischemic measures for all patients with ACS

Answer 2

Continuous ECG monitoring, aspirin (162 or 325 mg), sublingual nitroglycerin and IV nitroglycerin for continued ischemia or hypertension, morphine if pain is not relieved by sublingual nitroglycerin, oral beta-blocker and ACE inhibitor if the patient still hypertensive or has LV dysfunction (EF <40%)

Question 3

Antiplatelet therapy

Answer 3

Clopidogrel (Plavix), Prasugrel (Effient), Ticagrelor (Brilinta)

Question 4

Clopidogrel

Answer 4

16-50% of patients are resistant, metabolizes by CYP2C19

Question 5

Prasugrel

Answer 5

Higher rate of significant bleeding than Plavix

Contraindicated in the elderly, weight less than 132 lb (60 kg), in patients with history of stroke.

Question 6

Ticagrelor

Answer 6

More effective than Clopidogrel without increased bleeding risk
Higher than aspirin 81 mg makes medication less effective.

Question 7

Dual antiplatelet therapy duration

Answer 7

After receiving a drug-eluting stent, at least 1 year
After MI without revascularization, at least 1 year
After bare-metal metal stent, at least 1 month, ideally up to a year.

Do not stop antiplatelet agent until 6 months after DES or 1 month after BMS placement. Early withholding of antiplatelet drugs associated with increased risk of death and in-stent thrombosis

Question 8

Glycoprotein 2A/3B inhibitors

Answer 8

Abciximab, Eptifibatide, Tirofiban, Lamifiban

Only IV therapy is effective.
Indicated for high risk ACS patients (elevated troponin, hemodynamic instability, dynamic EKG changes)
Used less since introduction of dual oral antiplatelet therapy.

Question 9

Fibrinolytic therapy

Answer 9

Used in ACS only with ST elevation (as in STEMI or new left bundle branch block) if percutaneous coronary intervention is not available, and there is no contraindication, otherwise increases mortality.