External validation of modified EuroSCORE.

BACKGROUND: EuroSCORE is an adult cardiac surgery risk scoring method that is used worldwide, which has been shown to significantly overestimate the operative risk. We derived a new risk scoring method by modifying some of the risk factors included in the EuroSCORE algorithm and we validated it in an external database. METHODS: This study included 4,014 patients who underwent adult cardiac surgery at the Heart Centre, Tampere University Hospital, Finland. Operative risk was estimated by EuroSCORE and its modified version. RESULTS: In-hospital postoperative mortality rate was 3.2%. EuroSCORE (AUC for logistic EuroSCORE 0.82; 95% confidence interval (CI), 0.79-0.85) and modified score (AUC for logistic modified score 0.79; 95% CI, 0.75-0.83) performed well in predicting in-hospital mortality in this series. The mean logistic EuroSCORE was 8%, and the mean logistic modified score was 2.2%. Thus, the observed to expected ratio for in-hospital mortality was 0.4 for logistic EuroSCORE and 1.5 for logistic modified score. The difference between observed and predicted mortality rate matched correctly for increasing additive modified score, but not for EuroSCORE. The observed to predicted ratio in high-risk patients (within the 90th percentile of each risk algorithm) was 0.36 (13.2%/36.2% in 402 patients) for logistic EuroSCORE and 0.99 (14.7%/14.9% in 395 patients) for logistic modified score. CONCLUSIONS: This modified and simplified score, which includes most of EuroSCORE variables, seems to provide a more realistic estimation of postoperative mortality risk of patients undergoing any adult cardiac surgery.

Coronary artery bypass surgery in octogenarians: long-term outcome can be better than expected.

BACKGROUND: We have reviewed our experience with octogenarians undergoing coronary artery bypass grafting. METHODS: A consecutive series of 274 patients age 80 years or greater out of 3,474 patients who underwent isolated coronary artery bypass grafting. We have assessed the intrinsic risk aged 80 years or greater by comparing them with a propensity score-matched cohort of younger patients with similar operative risk (other than age). RESULTS: Thirty-day mortality (4.7% vs 1.3%, p<0.0001), combined adverse event rates (13.1% vs 6.6%, p<0.0001), and five-year survival (76.6% vs 90.4%, p<0.0001) were significantly poorer among patients aged 80 years or greater as compared with younger patients. These figures were, however, better than estimates of a recent systematic review by McKellar and colleagues (McKellar SH, Brown ML, Frye RL, Schaff HV, Sundt TM III. Comparison of coronary revascularization procedures in octogenarians: a systematic review and meta-analysis. Nat Clin Pract Cardiovasc Med 2008;5:738-46) (30-day mortality 7.2%, and five-year survival, 68%). When octogenarians were compared with 273 propensity score-matched patients aged less than 80 years, the 30-day mortality (4.8% vs 2.6%, p=0.17) and combined adverse event rates (13.2% vs 10.6%, p=0.36) did not significantly differ. Five-year survival, despite statistical significance, was not remarkably lower than that of propensity-matched patients aged less than 80 years (77.0% vs 81.3%, p=0.009). The decrease in survival of octogenarians was evident only during the first few months after surgery, but not later on. CONCLUSIONS: The results of this study suggest that immediate and five-year survival of octogenarians undergoing coronary artery bypass grafting may be even better than previously estimated. Survival of octogenarians may be suboptimal only during the first few months after surgery, whereas at five years may not differ remarkably from younger patients with otherwise similar operative risk.

Miniaturized versus conventional cardiopulmonary bypass in high-risk patients undergoing coronary artery bypass surgery.

OBJECTIVE: To review our results with the use of miniaturized cardiopulmonary bypass (Mini-CPB) versus conventional cardiopulmonary bypass (C-CPB) in high-risk patients (additive EuroSCORE>or=6) who have undergone coronary artery bypass graft surgery (CABG). PATIENTS AND METHODS: This study includes a consecutive series of 236 patients with an additive EuroSCORE>or=6 who underwent CABG, employing either C-CPB or Mini-CPB. Propensity score analysis was performed. RESULTS: The study groups had similar EuroSCOREs. Stroke rate was significantly higher among C-CPB patients (5.4% vs. 0%, p=0.026). In-hospital mortality (4.8% vs. 3.4%, p=0.75) and combined adverse end-point rate were higher in C-CPB patients (20.4% vs. 13.5%, p=0.18). Postoperative bleeding and need for transfusion were similar in the study groups, but re-sternotomy for bleeding was more frequent among C-CPB patients (4.8% vs. 1.1%, p=0.26). Seventy-four propensity matched pairs had similar immediate postoperative results: C-CPB patients had higher mortality (6.8% vs. 4.1%, p=0.72), stroke (5.4% vs. 0%, p=0.12) and combined adverse end-point rates (27.0% vs. 16.2%, p=0.11), but such differences failed to reach statistical significance. CONCLUSIONS: Mini-CPB achieved somewhat better results than C-CPB in these high-risk patients undergoing isolated CABG. This study confirmed that cerebral protection could be the main benefit associated with the use of Mini-CPB.

Safe time limits of aortic cross-clamping and cardiopulmonary bypass in adult cardiac surgery.

OBJECTIVES: We evaluated the impact of aortic cross-clamping time (XCT) and cardiopulmonary bypass time (CPBT) on the immediate and late outcome after adult cardiac surgery and attempted to identify their safe time limits. METHODS: This study includes 3280 patients who underwent adult cardiac surgery of various complexities. Myocardial protection was achieved with tepid continuous antegrade/retrograde blood cardioplegia. RESULTS: Receiver operating characteristics (ROC) curve analysis showed that XCT (area under the curve, AUC: 0.66), CPBT (AUC: 0.73) and CPBT with unclamped aorta (AUC: 0.77) were significantly associated with 30-day postoperative mortality. XCT of increasing 30-minute intervals (Odds Ratio (OR) 1.21, 95%C.I. 1.01-1.52) and CPBT of increasing 30-minute intervals (OR 1.47, 95%C.I. 1.27-1.71) were independent predictors of 30-day mortality. The best cutoff value for XCT was 150 min (30-day death: 1.8% vs. 12.2%, adjusted OR 3.07, 95%C.I. 1.48-6.39, accuracy 91.5%) and for CPBT 240 min (30-day death: 1.9% vs. 31.5%, adjusted OR 8.78, 95%C.I. 4.64-16.61, accuracy 96.0%). These parameters were significantly associated also with postoperative morbidity, particularly with postoperative stroke. CONCLUSIONS: XCT and CPBT are predictors of immediate postoperative morbidity and mortality. In our experience, cardiac procedures with CPBT<240 min and XCT<150 min were associated with a rather low risk of immediate postoperative adverse events independently of the complexity of surgery patient's operative risk.

Pulmonary function and immediate outcome of patients undergoing aortic valve replacement.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate whether pulmonary function, as assessed by spirometry, affects immediate outcome after aortic valve replacement (AVR). METHODS: Data relating to the preoperative percentages of predicted forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were retrieved from a series of 453 patients who underwent AVR, with or without coronary artery bypass surgery. RESULTS: The percentage of predictive FVC (odds ratio (OR) 0.952; 95% CI 0.914-0.990; AUC 0.749; p = 0.019), but not of predicted FEV1, nor any history of pulmonary disease, proved to be independent predictors of in-hospital mortality, even when adjusted for the logistic EuroSCORE. A percentage predictive FVC of < 80% proved to be the best cut-off (in-hospital mortality 6.3% versus 1.3%; p = 0.005; OR 5.100; 95% CI 1.544-16.849; specificity 69%, sensitivity 69%). The percentage of predictive FVC was found to be an independent predictor of stroke (OR 0.956; 95% CI 0.923-0.989; p = 0.009). Patients with a percentage of predictive FVC < 80% had a risk of postoperative stroke of 6.9% versus 1.9% among those patients with better FVC values (OR 3.769; 95% CI 1.342-10.581; p = 0.012). Patients with a percentage of predictive FVC < 80% (10.4% versus 4.2%; OR 2.648; 95% CI 1.225-5.724; p = 0.011) and a history of pulmonary disease (13.1% versus 5.1%; OR 2.808; 95% CI 1.117-6.694; p = 0.016) had a significantly higher risk of an intensive care unit stay of five or more days. Postoperative pneumonia was not associated with either spirometric parameters, nor with any history of pulmonary disease. CONCLUSION: Pulmonary disease, as indicated by decreased preoperative values of FVC and FEV1, is an important comorbidity factor in patients undergoing AVR surgery. Further studies are required to demonstrate whether the identification and treatment of these patients could improve their outcome after AVR.

Is it possible to improve the accuracy of EuroSCORE?

OBJECTIVE: We derived a new risk-scoring method by modifying some of the risk factors included in the EuroSCORE algorithm. METHODS: This study includes 3613 patients who underwent cardiac surgery at the Vaasa Central Hospital, Finland. The EuroSCORE variables, along with modified age classes (< 60 years, 60-69.9 years, 70-79.9 years and > or = 80 years), eGFR-based chronic kidney disease classes (classes 1-2, class 3 and classes 4-5) and the number of cardiac procedures, were entered into the regression analysis. RESULTS: An additive risk score was calculated according to the results of logistic regression by adding the risk of the following variables: patients' age classes (0, 2, 4 and 6 points), female (2 points), pulmonary disease (3 points), extracardiac arteriopathy (2 points), neurological dysfunction (4 points), redo surgery (3 points), critical preoperative status (8 points), left ventricular ejection fraction (> 50%: 0; 30-50%: 2 and < 30%: 3 points), thoracic aortic surgery (8 points), postinfarct septal rupture (9 points), chronic kidney disease classes (0, 3 and 6 points), number of procedures (1: 0; 2: 2 and 3 or more: 7 points). The modified score had a better area under the receiver operating characteristic curve (additive: 0.867; logistic: 0.873) than the EuroSCORE (additive: 0.835; logistic: 0.840) in predicting 30-day postoperative mortality. The modified score, but not EuroSCORE, correctly estimated the 30-day postoperative mortality. CONCLUSION: EuroSCORE still performs well in identifying high-risk patients, but significantly overestimates the immediate postoperative mortality. This study shows that the score's accuracy and clinical relevance can be significantly improved by modifying a few of its variables. This institutionally derived risk-scoring method represents a modification and simplification of the EuroSCORE and, likely, it would provide a more realistic estimation of the mortality risk after adult cardiac surgery.

Postoperative delirium and health related quality of life after coronary artery bypass grafting.

OBJECTIVES: We wanted to identify determinants for postoperative delirium and its influence on health related quality of life (HRQoL) during 36-month follow-up of coronary artery bypass (CABG) patients. DESIGN: A total of 302 patients were retrospectively analyzed. HRQoL was assessed prospectively by the 15D instrument. Delirium was diagnosed clinically. RESULTS: The incidence of delirium was 6.0%. The cumulative survival (all-cause death) in 36 months was 96.1% in patients without delirium and 77.8% in patients with delirium. Age, cerebral disease, chronic heart failure, male gender, postoperative pneumonia and low output syndrome were predictors for delirium. Delirium patients needed more resources i.e. intensive care or total duration of hospitalization and experienced no positive change in HRQoL. Moreover patients with high preoperative 15D score tended to suffer fairly severe but reversible impairment during the first 6 months after the operation. CONCLUSIONS: Preoperatively older and sicker patients with complicated postoperative course are at higher risk of developing delirium after CABG. Preoperative status and operative complications together with delirium may exert negative influence on forthcoming HRQoL, which is seen especially in patients with a relatively high preoperative level of HRQoL.

EuroSCORE predicts health-related quality of life after coronary artery bypass grafting.

Three hundred and two patients were evaluated for the EuroSCORE risk and health-related quality of life (HRQoL) during three years after CABG as assessed by the 15D instrument. Both additive and logistic EuroSCORE correlated significantly with the 15D score at 6, 18 and 36 months. A clinically important increase > or =0.03 in the 15D score was achieved by 50.6% of patients at 6 months, 40.0% at 18 months and 35.9% at 36 months. The rates were similar among patients with increasing EuroSCORE at 6 and 18 months, but tended to decrease at 36 months in the highest EuroSCORE group (EuroSCORE 0-2: 46.8%; 3-5: 34.8%; and 6-14: 33.3%, respectively, P=0.13). Both additive (area under the receiver operating characteristic curve, AUC: 0.582, P=0.024) and logistic EuroSCORE (AUC: 0.575, P=0.039) were predictors of a significant increase of the 15D score. The best cut-off value of the additive EuroSCORE for prediction of a clinically important improvement of the 15D score during 3-year follow-up was 3, as 46.7% of patients with EuroSCORE 0-3 and 30.1% of patients with a score >3 (P=0.006) improved clinically. The present study showed that the EuroSCORE also predicts long-term HRQoL after CABG.