Does sleeping late cause any heart problems even if you still get 8+ hours of sleep?

It should not: Sleeping late means getting up out of bed later than one's peers or family members. For a healthy, young adult who gets a typical amount of good sleep, sleeping late would just reflect a later time of going to bed. That may be due to working the late shift, or doing other daily activities that take up the late evening hours. That alone should not change one's heart disease risk or symptoms.