Unstable angina / non ST elevation myocardial infarction additional management considerations for antiplatelet and anticoagulant therapy

Overview of Additional Management Considerations for Antiplatelet and Anticoagulant Therapy in UA / NSTEMI
==ACC / AHA Guidelines (DO NOT EDIT) == {{cquote|

Class I
1. For UA / NSTEMI patients in whom an initial conservative strategy is selected and no subsequent features appear that would necessitate diagnostic angiography (recurrent symptoms / ischemia, heart failure or serious arrhythmias), a stress test should be performed. (Level of Evidence: B).


 * a. If, after stress testing, the patient is classified as not at low risk, diagnostic angiography should be performed. (Level of Evidence: A)
 * b. If, after stress testing, the patient is classified as being at low risk, the following instructions should be used in preparation for discharge (Level of Evidence: A):


 * Continue ASA indefinitely. (Level of Evidence: A)
 * Continue clopidogrel for at least 1 month (Level of Evidence: A) and ideally up to 1 year. (Level of Evidence: B)
 * Discontinue intravenous GP IIb/IIIa inhibitor if started previously. (Level of Evidence: A)
 * Continue UFH for 48 hours (Level of Evidence: A) or administer enoxaparin (Level of Evidence: A) or fondaparinux (Level of Evidence: B) for the duration of hospitalization, up to 8 days, and then discontinue anticoagulant therapy. (Level of Evidence: A)

2. For UA / NSTEMI patients in whom CABG is selected as a postangiography management strategy, the instructions noted below should be followed.


 * a. Continue ASA. (Level of Evidence: A)
 * b. Discontinue clopidogrel 5 to 7 d before elective CABG. (Level of Evidence: B) More urgent surgery, if necessary, may be performed by experienced surgeons if the incremental bleeding risk is considered acceptable. (Level of Evidence: C)
 * c. Discontinue intravenous GP IIb/IIIa inhibitor (eptifibatide or tirofiban) 4 h before CABG. (Level of Evidence: B)
 * d. Anticoagulant therapy should be managed as follows:


 * Continue UFH. (Class I Level of Evidence: B)
 * Discontinue enoxaparin 12 to 24 h before CABG and dose with UFH per institutional practice. (Level of Evidence: B)
 * Discontinue fondaparinux 24 h before CABG and dose with UFH per institutional practice. (Level of Evidence: B)
 * Discontinue bivalirudin 3 h before CABG and dose with UFH per institutional practice. (Level of Evidence: B)

3. In patients taking a thienopyridine in whom CABG is planned and can be delayed, it is recommended that the drug be discontinued to allow for dissipation of the antiplatelet effect (Level of Evidence: B). The period of withdrawal should be at least 5 days in patients receiving clopidogrel (Level of Evidence: B) and at least 7 days in patients receiving prasugrel (Level of Evidence: C) unless the need for revascularization and/or the net benefit of the thienopyridine outweighs the potential risks of excess bleeding. (Level of Evidence: C)

4. For UA / NSTEMI patients in whom PCI has been selected as a postangiography management strategy, the instructions noted below should be followed:
 * a. Continue ASA. (Level of Evidence: A)
 * b. Administer a loading dose of a thienopyridine if not started before diagnostic angiography. (Level of Evidence: A)
 * c. See Class IIa, #1, in this section.
 * d. Discontinue anticoagulant therapy after PCI for uncomplicated cases. (Level of Evidence: B)

5. For UA / NSTEMI patients in whom medical therapy is selected as a management strategy and in whom no significant obstructive CAD on angiography was found, antiplatelet and anticoagulant therapy should be administered at the discretion of the clinician (Level of Evidence: C). For patients in whom evidence of coronary atherosclerosis is present (e.g., luminal irregularities or intravascular ultrasound demonstrated lesions), albeit without flow-limiting stenoses, long-term treatment with ASA and other secondary prevention measures should be prescribed. (Level of Evidence: C)

6. For UA / NSTEMI patients in whom medical therapy is selected as a postangiography management strategy and in whom CAD was found on angiography, the following approach is recommended:


 * a. Continue ASA. (Class I Level of Evidence: A)
 * b. Administer a loading dose of clopidogrel if not given before diagnostic angiography. (Level of Evidence: B)
 * c. Discontinue intravenous GP IIb/IIIa inhibitor if started previously. (Level of Evidence: B)
 * d. Anticoagulant therapy should be managed as follows:


 * Continue intravenous UFH for at least 48 h or until discharge if given before diagnostic angiography. (Level of Evidence: A)
 * Continue enoxaparin for duration of hospitalization, up to 8 d, if given before diagnostic angiography. (Level of Evidence: A)
 * Continue fondaparinux for duration of hospitalization, up to 8 d, if given before diagnostic angiography. ( Level of Evidence: B)
 * Either discontinue bivalirudin or continue at a dose of 0.25 mg per kg per h for up to 72 h at the physician’s discretion, if given before diagnostic angiography. (Level of Evidence: B)

7. For UA / NSTEMI patients in whom a conservative strategy is selected and who do not undergo coronary angiography or stress testing, the instructions noted below should be followed:


 * a. Continue ASA indefinitely. (Class I Level of Evidence: A)
 * b. Continue clopidogrel for at least 1 month and ideally up to 1 year. (Level of Evidence: B)
 * c. Discontinue IV GP IIb/IIIa inhibitor if started previously. (Level of Evidence: A)
 * d. Continue UFH for 48 h or administer enoxaparin or fondaparinux for the duration of hospitalization, up to 8 d, and then discontinue anticoagulant therapy. (Level of Evidence: A)

8. For UA / NSTEMI patients in whom an initial conservative strategy is selected and in whom no subsequent features appear that would necessitate diagnostic angiography (recurrent symptoms / ischemia, HF, or serious arrhythmias), Left Ventricular Ejection Fraction should be measured. (Level of Evidence: B)

Class IIa
1. For UA / NSTEMI patients in whom PCI has been selected as a postangiography management strategy, it is reasonable to administer an IV GP IIb/IIIa inhibitor (abciximab, eptifibatide, or tirofiban) if not started before diagnostic angiography, particularly for troponin-positive and/or other high-risk patients. (Level of Evidence: A)

2. For UA / NSTEMI patients in whom PCI is selected as a post angiography management strategy, it is reasonable to omit administration of an intravenous GP IIb/IIIa antagonist if bivalirudin was selected as the anticoagulant and at least 300 mg of clopidogrel was administered at least 6 h earlier. (Level of Evidence: B)

3. If Left Ventricular Ejection Fraction is ≤40%, it is reasonable to perform diagnostic angiography. (Level of Evidence: B)

4. If Left Ventricular Ejection Fraction is >40%, it is reasonable to perform a stress test. (Level of Evidence: B)

Class IIb
1. Platelet function testing to determine platelet inhibitory response in patients with UA / NSTEMI (or, after ACS and PCI) on thienopyridine therapy may be considered if results of testing may alter management. (Level of Evidence: B)

2. Genotyping for a CYP2C19 loss of function variant in patients with UA / NSTEMI (or, after ACS and with PCI) on clopidogrel therapy might be considered if results of testing may alter management. (Level of Evidence: C)

Class III
1. Intravenous fibrinolytic therapy is not indicated in patients without acute ST segment elevation, a true posterior MI, or a presumed new left bundle branch block (LBBB). (Level of Evidence: A)}}