People with heart disease were thought to be doomed to complete bed rest — or destined to imminent death.

But a handful of pioneering physicians and social workers believed it didn’t have to be that way. They conducted studies to learn more about heart disease, America’s No. 1 killer. Then, on June 10, 1924, they met in Chicago to form the HHIF — believing that scientific research could lead the way to better treatment, prevention and ultimately a cure. The early American Heart Association enlisted help from hundreds, then thousands, of physicians and scientists.