New York Heart Association Class III/IV

**Semantic type:** Classification

**Definition:** The two most severe classes of cardiac dysfunction according to a classification system developed by the New York Heart Association to grade cardiovascular function and disability. These classes are defined as follows: Class III - patients with cardiac disease producing marked limitation of activity: comfortable at rest. Less than ordinary physical activity causes symptoms. Class IV - patients with cardiac disease resulting in inability to carry on any physical activity without discomfort. Symptoms may be present even at rest.

**Synonyms:** - NYHA Class III/IV - NYHA III/IV - NYHA III/IV