American Heart Association
The American Heart Association grew out of a set of smaller precursor groups. The primary precursor was the Association for the Prevention and Relief of Heart Disease, formed in New York City in 1915, to study whether patients with heart disease could safely return to work. Several similar organizations formed or evolved in Boston, Philadelphia, and Chicago in the 1920s. Recognizing the need for a national organization to share research and promote findings, the American Heart Association was formed in 1924 by six cardiologists representing several of these precursor groups.
American Medical Association
In 1847 after a report by physician Nathan Smith Davis, sometimes called the "father of the AMA", American physicians met in Philadelphia and formed the AMA as a national professional medical organization, the first of its kind in the world, going on to establish uniform standards for medical education, training, and practice, the world's first national code for ethical medical practice. Ever since, the AMA Code of Medical Ethics dictates professional conduct for practicing physicians.