|I||No symptoms and no limitation in ordinary physical activity, e.g. shortness of breath when walking, climbing stairs etc.|
|II||Mild symptoms (mild shortness of breath and/or angina) and slight limitation during ordinary activity.|
|III||Marked limitation in activity due to symptoms, even during less-than-ordinary activity, e.g. walking short distances (20-100 m).
Comfortable only at rest.
|IV||Severe limitations. Experiences symptoms even while at rest. Mostly bedbound patients.|