Chronic Treatment of CAD Flashcards
1
Q
Antiplatelet Drug Benefits
A
- Significantly reduce vascular events (especially MI) in patients with CAD with or without stents
- Prevent thrombotic complications following stent placements
2
Q
Stent Thrombosis
A
- Usually occurs in the first month after stent implantation
- Numerous cases of “late” stent thrombosis, especially those treated with DES, occuring months or years after stent
- Stent thrombosis usually catastrophic with life-threatening complications
3
Q
Predictors of Stent Thrombosis
A
- stenting of small vessels
- stenting multiple lesions
- use of long stents
- use of overlapping stents
- stenting ostial or bifurcation lesions
- suboptimal stent result (underexpansion, malapposition, or residual dissection)
- diabetes mellitus
- low ejection fraction
- advanced age
- acute coronary syndrome
- premature discontinuation of antiplatelet agents
- renal failure
4
Q
BMS + Drug Recommendation
A
- BMS: Bare-metal stent
- Recommended to place patient on aspirin + P2Y12 inhibitor to reduce stent thrombosis and cardiac events
- Duration of antiplatelet based on anticipated time for stent to be endothelialized
- Longer durations have fewer CV events but more bleeding
5
Q
DES
A
- Drug-eluting stents
- Shown to have delayed endothelialization
- Used more often in high-risk lesions
6
Q
Aspirin
A
- EC preparations usually are better tolerated than regular tablets
- No data suggesting 325 mg is better than lower dosages
- Increased risk of GI side effects when 325 mg given daily for chronic prophylaxis
- Monitor for bleeding/bruising GI upset
7
Q
P2Y12 Inhibitors Examples
A
- Clopidogrel (Plavix)
- Prasugrel (Effient)
- Ticagrelor (Brilinta)
8
Q
Clopidogrel
A
- Indications: ACS, recent MI/strok/PAD
- Only daily
- Take with 75-325 mg of aspirin daily
- Effected by pharmacogenomic variability
- No C/I
- Possible PPI interaction
- Cheapest option
9
Q
Prasugrel
A
- Indication: ACS with PCI
- Increased efficacy/bleeding risk than clopidogrel
- Once daily
- Take with 75-325 mg of aspirin per day
- C/I: prior transient ischemic attack or stroke
- Most expensive option
10
Q
Ticagrelor
A
- Indication: ACS, post-MI
- Increased clinical efficacy/bleeding compared to Clopidogrel
- Twice daily
- Use with =< 100 mg of aspirin per day
- C/I: prior intracranial hemorrhage, severe hepatic impairment
11
Q
Dipyridamole
A
- Unknown MoA
- Believed to inhibit platelet aggregation through phosphodiesterase inhibition which increases platelet cAMP
- NOT recommended as antiplatelet agent in patients with CAD
- Possible secondary prevention when used with aspirin for stroke
12
Q
Vorapaxar
A
- Zontivity
- PAR-1 antagonist which irreversibly inhibits thrombin-induced platelet aggregation
- Benefits: reduced the combined endpoint of CV death, MI, stroke, and urgent coronary revascularization in patients with a history of MI/PAD
- Risk: increased moderate-severe bleeding risk and intracranial bleeds
- C/I: history of stroke/TIA or active bleeding
- Expensive (~ the same as Ticagrelor)
- Role in therapy unresolved
13
Q
Clopidogrel + PPI Interaction
A
- Diminished effect when taken with PPI
- Omeprazole is primarily metabolized by CYP2C19 which is also part of Clopidogrel’s two step metabolization process
- Guidelines still recommend PPIs for those on dual platelet therapy who have prior upper GI bleed history (avoid omeprazole and esomeprazole)
- Use alternative PPI or H2 blocker
14
Q
Genetic Testing
A
- Not currently recommended under guidelines
- Might be considered in a patient at high risk for poor clinical outcomes to determine if he/she is predisposed to inadequate platelet inhibition with clopidogrel
- If identified to have such a predisposition, an alternative P2Y12 inhibitor MIGHT be considered
15
Q
Nitrates
A
- No data demonstrating efficacy at reducing cardiac events
- Primarily used to relieve chest discomfort
