Christenson et al developed a clinical prediction rule for identifying a patient with chest pain who can be discharged from the Emergency Department. This can help reduce health care costs without jeopardizing patient safety. The authors are from the University of British Columbia and several community hospitals in Vancouver, Canada.

Patient selection:

(1) adult with chest pain

(2) normal ECG or T-wave flattening only

(3) no prior history of ischemic chest pain, myocardial infarction, angina, therapy with nitroglycerin, or clear-cut effort-related angina

(4) no suspicion of pulmonary embolus, aortic dissection or other serious condition


Low risk characteristics for chest pain:

(1) pain not radiating to arm, neck and/or jaw

(2) pain that increases with a deep breath

(3) pain that increases with palpation


Suitable for early discharge - any of the following:

(1) age < 40 years of age

(2) age >= 40 AND low risk characteristics AND initial CK-MB < 3 micrograms/L

(3) age >= 40 AND low risk characteristics AND initial CK-MB >= 3 micrograms/L AND no change in ECG AND no rise in CK-MB within 2 hours of arrival AND no rise in troponin within 2 hours after arrival



• For criterion #3, a percent CK-MB might be safer.

• A person meeting criterion #3 might be worth closer scrutiny before discharging.

• Troponins may take a few hours to increase after a myocardial injury.

• A person with an anomalous coronary artery could present for the first time before age 40 years. Doing serum chemistries (and a drug screen) on a person with criterion #1 might be prudent.

• Combining the low risk characteristics requires absence of pain radiation.

• For criterion #2, any rise in CK-MB or troponin while in the ED would be reason to continue monitoring.

To read more or access our algorithms and calculators, please log in or register.