GRACE score

GRACE (Global Registry of Acute Coronary Events) score is used for risk assessment in ACS (acute coronary syndrome) which includes  nstemi, stemi and unstable angina. This score is more accurate because it is derived from a multinational registry of unselected patients and includes hospitals in Europe, Asia, North America, South America, Australia and New Zealand. Risk assessment should be performed at the time of hospital admission and is important because it gives an idea about probability of in-hospital death and also guides the appropriate treatment plan in nstemi and unstable angina .

Calculation of GRACE score:

Eight parameters are used for calculating GRACE score that include patient’s age, heart rate, systolic blood pressure, Killip class, serum creatinine level, cardiac arrest at hospital admission, ST-segment deviation in ECG and elevated cardiac marker.

1. Age:

Age (years) Score
≤ 30 0
30-39 8
40-49 25
50-59 41
60-69 58
70-79 75
80-89 91
≥ 90 100

2. Heart rate:

Heart rate (beats/minute) Score
≤ 50 0
50-69 3
70-89 9
90-109 15
110-149 24
150-199 38
≥ 200 46

 3. Systolic blood pressure:

Systolic blood pressure (mm Hg) Score
≤ 80 58
80-99 53
100-119 43
120-139 34
140-159 24
160-199 10
≥ 200 0

4. Killip class:

Killip class Score  
I  (No heart failure) 0
II  (Crackles audible in lower half of lung field) 20
III  (Crackles audible in whole lung field) 39
IV  (Cardiogenic shock) 59

5. Serum creatinine level:

Serum creatinine (μmol/L) Serum creatinine (mg/dl) Score
0-34 0-0.38 1
35-70 0.39-0.79 4
71-105 0.80-1.19 7
106-140 1.20-1.58 10
141-176 1.59-1.90 13
177-353 2.0-3.99 21
≥ 354 ≥ 4 28

 6. Cardiac arrest at hospital admission:

Cardiac arrest at hospital admission Score
Absent 0
Present 39

 7. ST-segment deviation in ECG:

ST-segment deviation in ECG Score
Absent 0
Present 28

 8. Elevated serum cardiac marker (Troponin or CK-MB):

Elevated cardiac marker Score
Absent 0
Present 14

Risk assessment by GRACE score:

We can assess risk by summation of score for all eight parameters.

Total score Risk assessment
≤ 100 Low risk patients– In-hospital death rate less than 1%
101-170 Medium risk patients – In-hospital death rate 1-9%
≥ 171 High risk patients – In-hospital death rate more than 9%

Treatment plan according to GRACE risk stratification:

In low risk patients with nstemi or unstable angina, medical treatment is appropriate and surgical intervention is reserved for those who fail to settle with medical treatment. By contrast, medium and high risk patients with nstemi or unstable angina should be treated with multiple drugs and considered for early coronary angiography and revascularization.  Revascularization can be done either by percutaneous coronary intervention (PCI) or by coronary artery bypass grafting (CABG).

Treatment plan in stemi is not depend on risk stratification. All patients with stemi should be treated immediately with reperfusion therapy by primary percutaneous coronary intervention (PCI) along with multiple drugs. Where PCI cannot be achieved within 120 minutes of diagnosis or PCI is not available, thrombolytic therapy (streptokinase, alteplase, tenecteplase, or reteplase) may be given.

Probability of in-hospital death by GRACE score:

Total score In-hospital death (%)
≤ 60 ≤ 0.2
70 0.3
80 0.4
90 0.6
100 0.8
110 1.1
120 1.6
130 2.1
140 2.9
150 3.9
160 5.4
170 7.3
180 9.8
190 13
200 18
210 23
220 29
230 36
240 44
≤ 250 ≤ 52

Example:

A male patient with nstemi is 60 years of age, has heart rate of 85 beats/minute, systolic blood pressure of 110 mm Hg, Killip class I , serum creatinine level of 50 μmol/L, did not have a cardiac arrest at admission but did have ST-segment depression in ECG and elevated serum cardiac marker. His GRACE score would be: 58 + 9 + 43 + 0 + 4 + 0 + 28 + 14 = 156. He is a medium risk patient and has about a 5% risk of having an in-hospital death.

Reference:

Newby DE, Grubb NR, Bradbury A. Cardiovascular disease. In: Colledge NR, Walker BR, Ralston SH, Penman ID eds. Davidson’s Principles & Practice of Medicine. 22st ed. China: Churchill Livingstone, 2014: 542, 591.