Final answer:
The purpose of the aspirin treatment is to reduce the levels of thromboxanes.
Step-by-step explanation:
The purpose of the 81 mg daily aspirin treatment for the 52-year-old man who suffered a heart attack is to reduce the levels of thromboxanes. Thromboxanes are substances that promote blood clotting, and by inhibiting their formation, aspirin helps prevent the formation of blood clots that can lead to another heart attack.