• Logo
  • SBMUJournals

Validation of the North American Chest Pain Rule in Prediction of Very Low-Risk Chest Pain; a Diagnostic Accuracy Study

Somayeh Valadkhani, Mohammad Jalili, Elham Hesari, Hadi Mirfazaelian




Introduction: Acute coronary syndrome accounts for more than 15% of the chest pains. Recently, Hess et al. developed North American Chest Pain Rule (NACPR) to identify very low-risk patients who can be safely discharged from emergency department (ED). The present study aimed to validate this rule in EDs of two academic hospitals.

Methods: A prospective diagnostic accuracy study was conducted on consecutive patients 24 years of age and older presenting to the ED with the chief complaint of acute chest pain, during March 2013 to June 2013. Chest pain characteristics, cardiac history, electrocardiogram findings, and cardiac biomarker measurement of patients were collected and screening performance characteristics of NACPR with 95% confidence interval were calculated using SPSS 21.

Results: From 400 eligible patients with completed follow up, 69 (17.25 %) developed myocardial infarction, 121 (30.25%) underwent coronary revascularization, and 4 (2%) died because of cardiac or unidentifiable causes. By using NACPR, 34 (8.50%) of all the patients could be considered very low- risk and discharged after a brief ED assessment. Among these patients, none developed above-mentioned adverse outcomes within 30 days. Sensitivity, specificity, positive prediction value, and negative prediction value of the rule were 100% (95% CI: 87.35 - 100.00), 45.35 (95% CI: 40.19 - 50.61), 14.52 (95% CI: 10.40 – 19.85), and 100 (95% CI: 97.18 - 100.00), respectively.

Conclusions: The present multicenter study showed that NACPR is a good screening tool for early discharge of patients with very low-risk chest pain from ED.


Acute coronary syndrome; decision support techniques; emergency service, hospital


Niska R, Bhuiya F, Xu J. National hospital ambulatory medical care survey: 2007 emergency department summary. Natl Health Stat Report. 2010;26(26):1-31.

Jalili M, Hejripour Z, Honarmand AR, Pourtabatabaei N. Validation of the Vancouver Chest Pain Rule: a prospective cohort study. Academic Emergency Medicine. 2012;19(7):837-42.

Pope JH, Aufderheide TP, Ruthazer R, Woolard RH, Feldman JA, Beshansky JR, et al. Missed diagnoses of acute cardiac ischemia in the emergency department. New England Journal of Medicine. 2000;342(16):1163-70.

Schull MJ, Vermeulen MJ, Stukel TA. The risk of missed diagnosis of acute myocardial infarction associated with emergency department volume. Annals of emergency medicine. 2006;48(6):647-55.

Pines JM, Szyld D. Risk tolerance for the exclusion of potentially life-threatening diseases in the ED. The American journal of emergency medicine. 2007;25(5):540-4.

Laupacis A, Sekar N. Clinical prediction rules: a review and suggested modifications of methodological standards. Jama. 1997;277(6):488-94.

Stiell IG, Wells GA. Methodologic standards for the development of clinical decision rules in emergency medicine. Annals of emergency medicine. 1999;33(4):437-47.

Hess EP, Brison RJ, Perry JJ, Calder LA, Thiruganasambandamoorthy V, Agarwal D, et al. Development of a clinical prediction rule for 30-day cardiac events in emergency department patients with chest pain and possible acute coronary syndrome. Annals of emergency medicine. 2012;59(2):115-25. e1.

Mahler SA, Miller CD, Hollander JE, Nagurney JT, Birkhahn R, Singer AJ, et al. Identifying patients for early discharge: performance of decision rules among patients with acute chest pain. International journal of cardiology. 2013;168(2):795-802.

Clancy M. Chest pain units: evidence of their usefulness is limited but encouraging.(Editorials). British Medical Journal. 2002;325(7356):116-8.

Selker HP, Beshansky JR, Griffith JL, Aufderheide TP, Ballin DS, Bernard SA, et al. Use of the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI) to assist with triage of patients with chest pain or other symptoms suggestive of acute cardiac ischemia: a multicenter, controlled clinical trial. Annals of Internal Medicine. 1998;129(11_Part_1):845-55.

Selker HP, Griffith JL, Patil S, Long WJ, d'Agostino R. A comparison of performance of mathematical predictive methods for medical diagnosis: identifying acute cardiac ischemia among emergency department patients. Journal of investigative medicine: the official publication of the American Federation for Clinical Research. 1995;43(5):468-76.

Hess EP, Thiruganasambandamoorthy V, Wells GA, Erwin P, Jaffe AS, Hollander JE, et al. Diagnostic accuracy of clinical prediction rules to exclude acute coronary syndrome in the emergency department setting: a systematic review. Cjem. 2008;10(04):373-82.

Steurer J, Held U, Schmid D, Ruckstuhl J, Bachmann LM. Clinical value of diagnostic instruments for ruling out acute coronary syndrome in patients with chest pain: a systematic review. Emergency Medicine Journal. 2010:emj. 2010.092619.

Christenson J, Innes G, McKnight D, Thompson CR, Wong H, Yu E, et al. A clinical prediction rule for early discharge of patients with chest pain. Annals of emergency medicine. 2006;47(1):1-10.

Keller T, Zeller T, Peetz D, Tzikas S, Roth A, Czyz E, et al. Sensitive troponin I assay in early diagnosis of acute myocardial infarction. New England Journal of Medicine. 2009;361(9):868-77.

Toll D, Janssen K, Vergouwe Y, Moons K. Validation, updating and impact of clinical prediction rules: a review. Journal of clinical epidemiology. 2008;61(11):1085-94.

DOI: https://doi.org/10.22037/emergency.v5i1.12325


  • There are currently no refbacks.