Risk stratification scores for predicting mortality in coronary artery bypass surgery.

BACKGROUND: Four risk-stratification scores (RSSs - Euro, French, CCS/Higgins, Parsonnet) were tested as predictors of mortality in coronary artery bypass grafting (CABG) surgery. METHODS: From March to April 2000, the perioperative courses of 245 consecutive CABG patients were compared to the predictions according to the RSSs. Sensitivity and specificity were determined with receiver operating characteristics (ROC) curves. RESULTS: CCS/Higgins uses the most easily acquired patient data, and rates emergency conditions as high-risk. Euro focuses on advanced age and septal rupture. French uses the smallest number of patient parameters and rates rare critical situations as high-risk. Parsonnet is partially based on the physician's subjective assessment of a "catastrophic state," making the scoring arbitrary. All RSSs gave similar (not significant) areas under the ROC curves regarding mortality (Euro 0.826 +/- 0.080, French 0.783 +/- 0.094, CCS/Higgins 0.820 +/- 0.060, Parsonnet 0.831 +/- 0.042). Predicted risk levels for the 11 patients who died differed between the RSSs--Higgins placed these patients in 3 of 5 risk levels with ascending distribution. The other RSSs placed these patients in the highest risk level except for one and two patients, respectively, who were placed in the lowest Euro and French risk level. Euro and Parsonnet placed about half of all patients with non-lethal outcome in the highest risk level. CONCLUSIONS: All RSSs satisfactorily estimated the group risk for mortality. No RSS expressed sufficient validity to predict individuals with lethal outcome. In clinical use, CCS/Higgins proved the most practicable.

Risk scores currently used in German heart surgery.

BACKGROUND: Risk scores (RS) in heart surgery assess mortality and morbidity and mirror the degree of severity of disease of the patients when presented for surgery. We examined the use and dissemination of RS in Germany. MATERIAL AND METHODS: Our survey included 79 German heart surgery institutes in Fall 1999 and Winter 2000. RESULTS: Four institutes did not respond. Out of 75 (ad 100 %) responders 56 (75 %) institutes did not use RS, 17 (22 %) institutes used one RS method and 2 (3 %) institutes used two RS methods. The most frequently applied RS methods were the Cleveland Clinic Score and the Euro Score (n = 7, each) followed by institution-specific, internally developed RS methods (n = 5), Parsonnet's RS (n = 1) and the RS from the STS database (n = 1). Fourteen institutes used RS for internal quality control. Of these, 2 institutes publish their RS data for external quality control. The patient-related individual procedure risk was used in 6 institutes. CONCLUSIONS: A quarter of the German heart surgery institutes use one or more RS methods. The most commonly used were the Cleveland Clinic Score and the Euro Score, followed by internally developed RS methods. RS methods were most frequently used for internal quality control. The degree of the severity of disease of the patients who presented for surgery could only be compared between a small number of institutes using the same RS.