Aspirin is known to have certain benefits for heart health, but the speed at which it improves heart health is not precisely defined. The cardioprotective effects of aspirin are generally associated with its ability to prevent blood clots, which can cause heart attacks and strokes [2].

According to the Mayo Clinic, aspirin therapy can help prevent heart attacks in people who have already had one, and it can also help prevent a first heart attack in some people [2]. However, the timeline for these benefits is not specified because the process of preventing blood clots and subsequent heart issues is gradual and depends on various factors, including the individual's health condition and the dosage of aspirin [2].

Johns Hopkins Medicine also explains that aspirin's antiplatelet properties can help prevent blood clots from forming, which is beneficial for heart health [3]. Nonetheless, the source does not provide information on the speed at which aspirin improves heart health [3].

In summary, while aspirin has established cardioprotective effects, the available information does not provide a clear answer to how quickly aspirin improves heart health. The benefits of aspirin on heart health are generally associated with its ability to prevent blood clots, but the timeline for these benefits is not explicitly defined [1][2][3].

Sources:
[1] DrugPatentWatch. (n.d.). Aspirin. Retrieved from <https://www.drugpatentwatch.com/p/tradename/ASPIRIN>
[2] Mayo Clinic. (2021, April 22). Daily aspirin therapy: Understand the benefits and risks. Retrieved from <https://www.mayoclinic.org/diseases-conditions/heart-disease/in-depth/daily-aspirin-therapy/art-20046797>
[3] Johns Hopkins Medicine. (n.d.). Is taking aspirin good for your heart? Retrieved from <https://www.hopkinsmedicine.org/health/wellness-and-prevention/is-taking-aspirin-good-for-your-heart>