Review Question - QID 108168

Clopidogrel is indicated for patients with coronary stents. It is an ADP receptor antagonist.

Percutaneous coronary intervention (PCI) is the first choice for the treatment of ST segment elevation myocardial infarctions (STEMIs). The goal is to open the occluded artery within 90 minutes of arriving to the emergency department. Depending on the type of stent placed, patients may need to be started on an antiplatelet agent, such as clopidogrel. Clopidogrel irreversibly blocks ADP receptors, which prevents activation of the GPIIb/IIIa receptor complex, thereby reducing platelet aggregation.

Campbell-Scherer and Green discuss the guidelines for STEMI management. Early recognition and prompt initiation are crucial for treating STEMIs. Patients are usually loaded with aspirin and clopidogrel after diagnosis and prior to PCI, unless there is a concern that the patient may need cardiac surgery. Beta-blockers are typically avoided because they can increase the risk of cardiogenic shock and death.

Brener et al. compare clopidogrel to prasugrel in patients undergoing PCI for STEMIs who are also receiving bivalirudin. Prasugrel is also an ADP receptor blocker, and is more potent than clopidogrel. Outcomes measured were infarct size at 30 days, procedural success and death at 1 year. The study showed that prasugrel was associated with improved efficacy and a similar safety profile compared to clopidogrel.

Figure 1 is an electrocardiogram with ST elevations in the precordial leads, concerning for a STEMI.

Incorrect answers:
Answer 1: Aspirin irreversibly inhibits cyclooxygenase.
Answer 3: Abciximab inhbits the GIIb/IIIa receptor complex.
Answer 4: Dipyridamole inhibits phosphodiesterase.
Answer 5: Bivalirudin is a direct thrombin inhibitor.