Salicylates
Salicylates have antiplatelet properties.
Aspirin (Ecotrin, Ascriptin, Bayer Aspirin, Bayer Aspirin Extra Strength, Tri-Buffered Aspirin)
Aspirin is an odorless white powdery substance that is available in 81-mg, 325-mg, and 500-mg tablets for oral use. When exposed to moisture, it hydrolyzes into salicylic acid and acetic acids. Aspirin is a stronger inhibitor of both prostaglandin synthesis and platelet aggregation than other salicylic acid derivatives are. Its acetyl group is responsible for inactivation of cyclooxygenase via acetylation. Aspirin is hydrolyzed rapidly in plasma, and elimination follows zero-order pharmacokinetics.
Aspirin irreversibly inhibits platelet aggregation by inhibiting platelet cyclooxygenase. This, in turn, inhibits conversion of arachidonic acid to prostaglandin I2 (PGI2, a potent vasodilator and inhibitor of platelet activation) and thromboxane A2 (TXA2, a potent vasoconstrictor and platelet aggregator). Platelet inhibition lasts for the life of cell (approximately 10 days).
Aspirin may be used in low doses to inhibit platelet aggregation and improve complications of venous stasis and thrombosis. It reduces the likelihood of myocardial infarction (MI) and is also very effective in lowering the risk of stroke. Early administration of aspirin in patients with acute MI may reduce cardiac mortality in the first month.
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This ECG represents a patient who came in to the emergency department with 8/10 chest pain. The patient had old right bundle-branch block (RBBB) and left ventricular hypertrophy (LVH), and this compared similarly to his previous ECGs.
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Classic Wellens syndrome T-wave changes. ECG was repeated on a patient who came in to the emergency department with 8/10 chest pain after becoming pain free secondary to medications. Notice the deep T waves in V3-V5 and slight biphasic T wave in V6 in this chest pain– free ECG. The patient had negative cardiac enzyme levels and later had a stent placed in the proximal left anterior descending (LAD) artery.
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A 57-year-old with 4/10 pressurelike chest pain. Improvement with treatment by EMS. The patient had this ECG on arrival. Notice perhaps the beginning of a small biphasic T wave in V2.
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Pain-free ECG of a 57-year-old patient who presented with 4/10 pressurelike chest pain. Notice after the patient was treated with medications and pain subsided, the ECG shows T-wave inversion in V2 and biphasic T waves in V3-V5. This more closely resembles the less common presentation of Wellens syndrome with a biphasic T-wave pattern. This patient had a cardiac catheterization that showed a subtotal occlusion of the proximal left anterior descending (LAD) artery, which was stented, and the patient did well.
