Scoring Systems for Risk Stratification in Patients Undergoing Cardiac Surgery

Published:March 06, 2021DOI:
      Cardiac surgery is associated with significant mortality rates. Careful selection of surgical candidates is, therefore, vital to optimize morbidity and mortality outcomes. Risk scores can be used to inform this decision-making process. The European System for Cardiac Operative Risk Evaluation Score and the Society of Thoracic Surgeons score are among the most commonly used risk scores. There are many other scoring systems in existence; however, no perfect scoring system exists, therefore, additional research is needed as clinicians strive toward a more idealized risk stratification model.
      The purpose of this review is to discuss the advantages and limitations of some of the most commonly used risk stratification systems and use this to determine what an ideal scoring system might look like. This includes not only the generalizability of available scores but also their ease of use and predictive power.

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      1. The National Institute for Cardiovascular Outcomes Research. National adult cardiac surgery audit. 2019 summary report. Available at: Accessed August 9, 2020.

        • Bouchard T
        • Subichin M
        • Firstenberg MS.
        Fifty years of cardiac surgery: Innovation, evolution, and revolution in cardiovascular therapies.
        IJAM. 2019; 5: 156-164
        • Aneman A
        • Brechot N
        • Brodie D
        • et al.
        Advances in critical care management of patients undergoing cardiac surgery.
        Intensive Care Med. 2018; 44: 799-810
        • Bridgewater B
        • Keogh B
        • Kinsman R
        • et al.
        Sixth National Adult Cardiac Surgical Database report 2008.
        The Society for Cardiothoracic Surgery in Great Britain and Ireland, 2020 (Available at:) (Accessed August 9)
        • Nicolini F
        • Agostinelli A
        • Vezzani A
        • et al.
        The evolution of cardiovascular surgery in elderly patient: A review of current options and outcomes.
        Biomed Res Int. 2014; 736298
        • Hote M.
        Cardiac surgery risk scoring systems: In quest for the best.
        Heart Asia. 2018; 10e011017
        • Prins C
        • Jonker IDV
        • Smit FE
        • et al.
        Cardiac surgery risk-stratification models.
        Cardiovasc J Afr. 2012; 23: 160-164
        • Sullivan PG
        • Wallach JD
        • Ioannidis JPA.
        Meta-analysis comparing established risk prediction models (EuroSCORE II, STS score, and ACEF score) for perioperative mortality during cardiac surgery.
        Am J Card. 2016; 118: 1574-1582
        • Parsonnet V
        • Dean D
        • Bernstein AD.
        A method of uniform stratification of risk for evaluating the results of surgery in acquired adult heart disease.
        Circulation. 1989; 79: I3-12
        • Krishna N
        • Varma PK.
        Risk stratification in cardiac surgery.
        Indian J Thorac Cardiovasc Surg. 2015; 31: 224-233
        • Giessler HJ
        • Holzl P
        • Marohl S
        • et al.
        Risk stratification in heart surgery: Comparison of six score systems.
        Eur J Cardiothorac Surg. 2000; 17: 400-406
        • Chung W
        • Chen C
        • Lee F
        • et al.
        Validation of scoring systems that predict outcomes in patients with coronary artery disease undergoing coronary artery bypass grafting surgery.
        Medicine. 2015; 94: e927
        • Lawrence DR
        • Valencia O
        • Smith EEJ
        • et al.
        Parsonnet score is a good predictor of the duration of intensive care unit stay following cardiac surgery.
        Heart. 2000; 83: 429-432
        • Gabrielle F.
        Is the Parsonnet's score a good predictive score of mortality in adult cardiac surgery: Assessment by a French multicentre study.
        Eur J Cardiothorac Surg. 1997; 11: 406-414
        • Geissler H.
        Risk stratification in heart surgery: Comparison of six score systems.
        Eur J Cardiothorac Surg. 2000; 17: 400-406
        • Dupuis JY
        • Wang F
        • Nathan H
        • et al.
        The cardiac anesthesia risk evaluation score: A clinically useful predictor of mortality and morbidity after cardiac surgery.
        Anesthesiology. 2001; 94: 194-204
        • Hsieh C
        • Peng S
        • Tsai T
        • et al.
        Prediction for major adverse outcomes in cardiac surgery: Comparison of three prediction models.
        JFMA. 2007; 106: 759-767
        • Higgins TL
        • Estafanous FG
        • Loop FD
        • et al.
        Stratification of morbidity and mortality outcome by preoperative risk factors in coronary artery bypass patients. A clinical severity score.
        JAMA. 1992; 267: 2344-2348
        • Ranucci M
        • Castelvecchio S
        • Menicanti L
        • et al.
        Risk of assessing mortality risk in elective cardiac operations.
        Circulation. 2009; 119: 3053-3061
        • Thakar C
        • Arrigain S
        • Worley S
        • et al.
        A clinical score to predict acute renal failure after cardiac surgery.
        J Am Soc Nephrol. 2004; 16: 162-168
        • Jiang W
        • Teng J
        • Xu J
        • et al.
        Dynamic predictive scores for cardiac surgery–associated acute kidney injury.
        J Am Heart Assoc. 2016; 5
        • Kurki T.
        Performance of three preoperative risk indices; CABDEAL, EuroSCORE and Cleveland models in a prospective coronary bypass database.
        Eur J Cardiothorac Surg. 2002; 21: 406-410
        • Nashef SA
        • Roques F
        • Michel P
        • et al.
        European system for cardiac operative risk evaluation (EuroSCORE).
        Eur J Cardiothorac Surg. 1999; 16: 9-13
        • Roques F
        • Michel P
        • Goldstone AR
        • et al.
        Eur Heart J. 2003; 24: 882-883
        • Nashef SA
        • Roques F
        • Sharples LD
        • et al.
        EuroSCORE II.
        Eur J Cardiothorac Surg. 2012; 41: 734-745
        • Roques F
        • Nashef SA
        • Michel P
        • et al.
        Risk factors and outcome in European cardiac surgery: Analysis of the EuroSCORE multinational database of 19030 patients.
        Eur J Cardiothorac Surg. 1999; 15: 816-823
        • Grant SW
        • Hickey GL
        • Dimarakis I
        • et al.
        Performance of the EuroSCORE models in emergency cardiac surgery.
        Circ Cardiovasc Qual Outcomes. 2013; 6: 178-185
        • Yap CH
        • Reid C
        • Yii M
        • et al.
        Validation of the EuroSCORE model in Australia.
        Eur J Cardiothorac Surg. 2006; 29: 441-446
        • Nashef SA
        • Roques F
        • Hammill BG
        • et al.
        Validation of European System for Cardiac Operative Risk Evaluation (EuroSCORE) in North American cardiac surgery.
        Eur J Cardiothorac Surg. 2002; 22: 101-105
        • Pitkanen O
        • Niskanen M
        • Rehnberg S
        • et al.
        Intra-institutional prediction of outcome after cardiac surgery: Comparison between a locally derived model and the EuroSCORE.
        Eur J Cardiothorac Surg. 2000; 18: 703-710
        • Zingone B
        • Pappalardo A
        • Dreas L.
        Logistic versus additive EuroSCORE. A comparative assessment of the two models in an independent population sample.
        Eur J Cardiothorac Surg. 2004; 26: 1134-1140
        • Hogervorst EK
        • Rosseel PMJ
        • van de Watering LMG
        • et al.
        Prospective validation of the EuroSCORE II risk model in a single Dutch cardiac surgery centre.
        Neth Heart J. 2018; 26: 540-551
        • Parolari A
        • Pesce LL
        • Trezzi M
        • et al.
        Performance of EuroSCORE in CABG and off-pump coronary artery bypass grafting: Single institution experience and meta-analysis.
        Eur Heart J. 2009; 3: 297-304
        • Guida P
        • Mastro F
        • Scrascia G
        • et al.
        Performance of the European System for Cardiac Operative Risk Evaluation II: A meta-analysis of 22 studies involving 145,592 cardiac surgery procedures.
        J Thorac Cardiovasc Surg. 2014; 148: 3049-3057
        • Nishida T
        • Sonoda H
        • Oishi Y
        • et al.
        The novel EuroSCORE II algorithm predicts the hospital mortality of thoracic aortic surgery in 461 consecutive Japanese patients better than both the original additive and logistic EuroSCORE algorithms.
        Interact Cardiovasc Thorac Surg. 2014; 18: 446-450
      2. The Society of Thoracic Surgeons. Risk calculator. Available at: Accessed August 14, 2020.

        • Kirmani BH
        • Mazhar K
        • Saleh HZ
        • et al.
        External validity of the Society of Thoracic Surgeons risk stratification tool for deep sternal wound infection after cardiac surgery in a UK population.
        Interact Cardiovasc Thorac Surg. 2013; 17: 479-484
        • Shahian DM
        • O'Brien SM
        • Filardo G
        • et al.
        The Society of Thoracic Surgeons 2008 cardiac surgery risk models: Part 3—valve plus coronary artery bypass grafting surgery.
        Ann Thorac Surg. 2009; 88: S43-S62
        • Puskas J
        • Kilgo P
        • Thourani V
        • et al.
        The Society of Thoracic Surgeons 30-day predicted risk of mortality score also predicts long-term survival.
        Ann Thorac Surg. 2012; 93: 26-35
        • Lancaster T
        • Schill M
        • Greenberg J
        • et al.
        Long-term survival prediction for coronary artery bypass grafting: Validation of the ASCERT model compared with the Society of Thoracic Surgeons predicted risk of mortality.
        Ann Thorac Surg. 2018; 105: 1336-1343
        • Balan P
        • Nguyen T
        • Estrera A
        • et al.
        STS risk score as a predictor of 30 day mortality in transcatheter versus surgical aortic valve replacement.
        J Am Coll Cardiol. 2016; 67: 248
        • Bouabdallaoui N
        • Stevens S
        • Doenst T
        • et al.
        Society of Thoracic Surgeons risk score and EuroSCORE-2 appropriately assess 30-day postoperative mortality in the STICH trial and a contemporary cohort of patients with left ventricular dysfunction undergoing surgical revascularization.
        Circulation. 2018; 11
        • Ad N
        • Holmes SD
        • Patel J
        • et al.
        Comparison of EuroSCORE II, original EuroSCORE, and the Society of Thoracic Surgeons risk score in cardiac surgery patients.
        Ann Thorac Surg. 2016; 102: 573-579
        • Wendt D
        • Osswald B
        • Kayser K
        • et al.
        Society of Thoracic Surgeons score is superior to the EuroSCORE determining mortality in high risk patients undergoing isolated aortic valve replacement.
        Ann Thorac Surg. 2009; 88: 468-475
        • Mullen MG
        • Michaels AD
        • Mehaffey JH
        • et al.
        Risk associated with complications and mortality after urgent surgery vs elective and emergency surgery: Implications for defining “quality” and reporting outcomes for urgent surgery.
        JAMA Surg. 2017; 152: 768-774
        • Ranucci M
        • Di Dedda U
        • Castelvecchio S
        • et al.
        In search of the ideal risk-scoring system for very high-risk cardiac surgical patients: A two-stage approach.
        J Cardiothorac Surg. 2016; 11: 13
        • Aalberts JJ
        • Boonstra PW
        • van den Berg MP
        • et al.
        In-hospital mortality and three-year survival after repaired acute type A aortic dissection.
        Neth Heart J. 2009; 17: 226-231
        • Barmettler H
        • Immer FF
        • Berdat PA
        • et al.
        Risk-stratification in thoracic aortic surgery: Should the EuroSCORE be modified?.
        Eur J Cardiothorac Surg. 2004; 25: 691-694
        • Ghoreishi M
        • Wise ES
        • Croal-Abrahams L
        • et al.
        A novel risk score predicts operative mortality after acute type A aortic dissection repair.
        Ann Thorac Surg. 2018; 106: 1759-1766
        • Williams JB
        • Peterson ED
        • Zhao Y
        • et al.
        Contemporary results for proximal aortic replacement in North America.
        J Am Coll Cardiol. 2012; 60: 1156-1162
        • Wagner MA
        • Wang H
        • Benrashid E
        • et al.
        Risk prediction model for major adverse outcome in proximal thoracic aortic surgery.
        Ann Thorac Surg. 2019; 107: 795-801
        • Bashir M
        • Shaw MA
        • Grayson AD
        • et al.
        Development and validation of elective and nonelective risk prediction models for in-hospital mortality in proximal aortic surgery using the National Institute for Cardiovascular Outcomes Research (NICOR) database.
        Ann Thorac Surg. 2016; 101: 1670-1676
        • Peguero JG
        • Lo Presti S
        • Issa O
        • et al.
        Simplified prediction of postoperative cardiac surgery outcomes with a novel score: R2CHADS2.
        Am Heart J. 2016; 177: 153-159
        • Brown JR
        • MacKenzie TA
        • Dacey LJ
        • et al.
        Using biomarkers to improve the preoperative prediction of death in coronary artery bypass graft patients.
        J Extra Corpor Technol. 2010; 42: 293-300
        • Merchant ML
        • Brier ME
        • Slaughter MS
        • et al.
        Biomarker enhanced risk prediction for development of AKI after cardiac surgery.
        BMC Nephrol. 2018; 19: 102
        • Shahian DM
        • Grover FL.
        Biomarkers and risk models in cardiac surgery.
        Circulation. 2014; 130: 932-935