Cold email press release lead gen

I built a B2B SaaS product. Unfortunately, most of my potential clients are engineering managers. This means I have to resort to cold email.

Lately, I found a decent way to generate leads. I search through a PR database for keywords related to my niche. From there I do my best to find the email for the appropriate decision maker.

Does anyone have experience with this lead gen tactic? I don’t see much when I google around. Are there any pitfalls I should be aware of? Are there any better ways to automate this process that could help me out?