I

Ordinary physical activity does not cause undue fatigue, dyspnea, or palpitations.

None

Can complete any activity requiring ≤ 7 MET:

• Carry 11 kg up 8 steps

• Carry objects weighing 36 kg

• Shovel snow

• Spade soil

• Ski

• Play squash, handball, or basketball

• Jog or walk 8 km/hour

II

Ordinary physical activity causes fatigue, dyspnea, palpitations, or angina.

Mild

Can complete any activity requiring ≤ 5 MET:

• Sexual intercourse without stopping

• Garden

• Roller skate

• Walk 7 km/hour on level ground

• Climb one flight of stairs at a normal pace without symptoms

III

Comfortable at rest; less than ordinary physical activity causes fatigue, dyspnea, palpitations, or angina.

Moderate

Can complete any activity requiring ≤ 2 MET:

• Shower or dress without stopping

• Strip and make a bed

• Clean windows

• Play golf

• Walk 4 km/hour

IV

Symptoms occur at rest; any physical activity increases discomfort.

Severe

Cannot do or cannot complete any activity requiring ≥ 2 MET; cannot do any of the above activities