Pros
The life-saving mission of HeartFlow is hard to beat in terms of finding motivation on a daily basis. You get to make a real difference, and your impact is tangible, not hidden behind layers of business. There are serious, challenging problems to work on in multiple fields (Medical Research, Physics, Backend & Frontend, UI/UX, Machine Learning, Analytical Geometry, Graphics & Rendering). More of it is cutting-edge than not. HeartFlow has a genuine commitment to helping patients, doctors, and hospitals. There's no lack of integrity here. Management listens to you and chases transparency ruthlessly.
Cons
FDA compliance is a complex burden for any medical company, and HeartFlow is no exception. It's a team effort, and you will have to do your part. The company mission is incredibly motivating, so it can be hard to force yourself away from work at times. The company culture doesn't promote overwork, but you may need to make a real effort to keep yourself in check and take the personal time you need.