There are real time live-streaming as well as on demand options for the AHA 2019 meeting that would allow one to view AHA presentations including the late-breakers. Not free though.
https://professional.heart.org/professional/EducationMeetings/MeetingsLiveCME/ScientificSessions/UCM_488605_Sessions-LIVE.jsp
https://aha.ondemand.org/aha/live/34/page/294