Skip to main content
. Author manuscript; available in PMC: 2011 Jun 17.
Published in final edited form as: Prog Pediatr Cardiol. 2009 Dec;27(1):4–11. doi: 10.1016/j.ppedcard.2009.09.003

Table 2.

WHO functional classification in pulmonary hypertension.

World Health Organization Functional Assessment (Class)
I Patients with PH but without resulting limitation of physical activity. Ordinary
physical activity does not cause undue dyspnea or fatigue, chest pain, or near
syncope.
II Patients with PH resulting in slight limitation of physical activity. Comfortable
at rest; ordinary physical activity causes undue dyspnea or fatigue, chest pain,
or near syncope.
III Patients with PH resulting in marked limitation of physical activity.
Comfortable at rest; less than ordinary activity causes undue dyspnea or
fatigue, chest pain, or near syncope.
IV Patients with PH with inability to carry out any physical activity without
symptoms. These patients manifest signs of right-heart failure. Dyspnea and/or
fatigue may even be present at rest. Discomfort is increased by any physical
activity

PH = pulmonary hypertension.