Table 1 Diagnostic criteria of Traditional Chinese Medicine (TCM) syndromes

Main symptoms

1. Chest pain

2. Sense of suppression in the chest

The included patients need to have one of the main symptoms

Qi deficiency syndrome

1. Palpitation and shortness of breath

2. Fatigue

3. Spontaneous sweating

4. Pale complexion

5. Pale tongue

6. Corpulent tender tongue with indentations in the margin of the tongue

7. Weak pulse

The included patients need to have two or more of the above symptoms

Blood stasis syndrome

1. Dark purple lips, complexions or claws

2. Purple, dark or bruised tongue

3. Enlarged sublingual venation

4. Uneven pulse

The included patients need to have two or more of the above symptoms

Phlegm turbidity syndrome

1. Being overweight

2. Thick and greasy tongue

3. Slippery pulse

The included patients need to have two or more of the above symptoms