Heart, the American rock band, was formed in Seattle, Washington, in 1973. This pivotal year marked the beginning of their musical journey, evolving from previous projects by founding members Roger Fisher and Steve Fossen, including The Army (1967–1969), Hocus Pocus (1969–1970), and White Heart (1970–1973).
While the provided text mentions several instances of "heart" in relation to medical procedures and research (heart transplants, heart attacks, etc.), the question's context clearly points to the rock band Heart. Therefore, these other instances are irrelevant to answering the query.
