@mchler73 My understanding is that an AI shows what is labeled “significant” better outcomes than Tamoxifen but that they’re talking very minor differences in risk. In the scheme of things a half a percent of risk, while maybe scientifically significant, might not be important to me.
I agree with any heart issues an AI should be critically evaluated for how your entire health would be benefited or not.

I’m editing this before edit window closes - I’m leaving my original comment above. But I just searched about Tamoxifen and skin cancer - looks like it acts as an agonist to estrogen availability in the skin, and may increase the risk of developing skin cancer. I know this is your other concern right now.
The link for the info below - but you may want to investigate further. I’m sorry that the decision making is like a game of Jenga. Which block will hold it all up, and which will topple it.
https://www.tandfonline.com/doi/full/10.2147/cia.s798#d1e624