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Background: The availability of two contemporary sources of information about coronary artery bypass graft (CABG) interventions, allowed 1) to verify the feasibility of performing outcome evaluation studies using administrative data sources, and 2) to compare hospital performance obtainable using the CABG Project clinical database with hospital performance derived from the use of current administrative data., Methods: Interventions recorded in the CABG Project were linked to the hospital discharge record (HDR) administrative database. Only the linked records were considered for subsequent analyses (46% of the total CABG Project). A new selected population "clinical card-HDR" was then defined. Two independent risk-adjustment models were applied, each of them using information derived from one of the two different sources. Then, HDR information was supplemented with some patient preoperative conditions from the CABG clinical database. The two models were compared in terms of their adaptability to data. Hospital performances identified by the two different models and significantly different from the mean was compared., Results: In only 4 of the 13 hospitals considered for analysis, the results obtained using the HDR model did not completely overlap with those obtained by the CABG model. When comparing statistical parameters of the HDR model and the HDR model + patient preoperative conditions, the latter showed the best adaptability to data., Conclusions: In this "clinical card-HDR" population, hospital performance assessment obtained using information from the clinical database is similar to that derived from the use of current administrative data. However, when risk-adjustment models built on administrative databases are supplemented with a few clinical variables, their statistical parameters improve and hospital performance assessment becomes more accurate.

Objectives: To compare the risk-adjustment model empirically derived from the 'Italian CABG Outcome Project' with that of the additive and logistic EuroSCORE in terms of accuracy, predictive power and ability to rank hospital performances., Methods: The Italian CABG model, the logistic and additive EuroSCORE were applied to the Italian CABG population; the observed deaths/expected deaths (O/E) ratios, as obtained by the three models, were computed for each Italian cardiac surgery centre and for six classes of risk-stratified patients. The performance of the three models in predicting the 30-day mortality was formally assessed for calibration (Hosmer-Lemeshow test) and discrimination (ROC area). According to the three models, risk-adjusted mortality rates (RAMR = O/E x Italian CABG population mortality rate) were estimated for each centre; possible differences were detected in the identification of hospitals with mortality rates higher and lower than average., Results: The Italian CABG model uses fewer variables than the EuroSCORE system (14 vs 17) and exhibits the best performance in terms of discrimination and calibration. Contrary to the other tested models, the logistic EuroSCORE shows a significant Hosmer-Lemeshow test (chi(H-L)(2)=19.30, p<0.0001), indicating unsatisfactory calibration, and a clear predicted death overestimation in each of the considered risk classes (O/E = 0.4). When a proper recalibration procedure is applied, the logistic EuroSCORE performance parameters achieve acceptable levels. The Italian CABG model identified seven centres as having higher than average mortality, while the EuroSCORE identified the same seven centres plus one other. The Italian CABG model identified eight centres with lower than average mortality, five of which were identified by the additive EuroSCORE and four of which were identified by the logistic EuroSCORE. The additive EuroSCORE identified four more and the logistic EuroSCORE three more low mortality centres., Conclusions: Although this analysis reveals a satisfactory concordance between results from the three models, a detailed comparison shows that the Italian CABG model uses fewer variables and performs better than the others. Nevertheless, when properly recalibrated, the EuroSCORE model can be exported to the Italian population and used to rank hospital performance and evaluate preoperative risk of patients undergoing open-heart surgery.

Background: Hierarchical modelling represents a statistical method used to analyze nested data, as those concerning patients afferent to different hospitals. Aim of this paper is to build a hierarchical regression model using data from the "Italian CABG outcome study" in order to evaluate the amount of differences in adjusted mortality rates attributable to differences between centres., Methods: The study population consists of all adult patients undergoing an isolated CABG between 2002-2004 in the 64 participating cardiac surgery centres.A risk adjustment model was developed using a classical single-level regression. In the multilevel approach, the variable "clinical-centre" was employed as a group-level identifier. The intraclass correlation coefficient was used to estimate the proportion of variability in mortality between groups. Group-level residuals were adopted to evaluate the effect of clinical centre on mortality and to compare hospitals performance. Spearman correlation coefficient of ranks (rho) was used to compare results from classical and hierarchical model., Results: The study population was made of 34,310 subjects (mortality rate = 2.61%; range 0.33-7.63). The multilevel model estimated that 10.1% of total variability in mortality was explained by differences between centres. The analysis of group-level residuals highlighted 3 centres (VS 8 in the classical methodology) with estimated mortality rates lower than the mean and 11 centres (VS 7) with rates significantly higher. Results from the two methodologies were comparable (rho = 0.99)., Conclusion: Despite known individual risk-factors were accounted for in the single-level model, the high variability explained by the variable "clinical-centre" states its importance in predicting 30-day mortality after CABG.

The aim of the study was to determine the value of brain natriuretic peptide for the identification of diastolic dysfunction status in congestive heart failure. We studied 204 patients with stable heart failure. Brain natriuretic peptide plasma levels were correlated with echocardiographic parameters of diastolic dysfunction. Diastolic dysfunction was classified as mild (abnormal echocardiographic relaxation pattern) and severe (pseudo-normal or restrictive pattern). A significant correlation between brain natriuretic peptide levels and the other parameters was detected. Brain natriuretic peptide dosage, then, seems to be a reliable tool for the assessment of diastolic dysfunction status in patients with congestive heart failure.

Background: Whether brain natriuretic peptide (BNP), a neurohormone marker of ventricular dysfunction, correlates with an enhanced ventilatory response (EVR) during cardiopulmonary exercise test, a well-known predictor of prognosis, in systolic heart failure (HF) is currently unknown., Material/methods: Resting BNP was measured in 134 consecutive stable outpatients aged 69 +/- 11 years with mild to moderate HF and LV ejection fraction (LVEF) < 40% who performed a maximal exercise test. EVR was assessed as the slope of the relation between minute ventilation and carbon dioxide production (VE/VCO2 slope) > or = 35., Results: LVEF averaged 33 +/- 7%, BNP 350 +/- 396 pg/ml, and the VE/VCO2 slope 36 +/- 8. Fifty-six of 123 patients (45%) had EVR. BNP correlated with VE/VCO2 slope (r = 0.453; p < 0.01). By multivariate logistic regression, plasma BNP was the only independent predictor of EVR (RR: 1.004 per unit increment, 95% CI: 1.002-1.006, p < 0.0001). A BNP > or = 160 pg/ml had 86% sensitivity, 67% specificity, and 76% overall accuracy for the prediction of EVR (chi square: 37.4, RR 12.2, 95% CI: 4.96-30.3, p < 0.0001, AUC 0.815 (95%CI. 0.738-0.892))., Conclusions: In systolic HF, plasma BNP is related to an enhanced ventilatory response to exercise and offers a simple and reliable alternative to the cardiopulmonary exercise test in patients with inability or contraindications to exercise.

Objective: During the last decade, a worldwide growing interest in evaluating performance of health services through 'outcome studies' took place. This study started in early 2002 and represents the first National Health System (NHS) experience to evaluate adjusted performance indicators at national level. The aim of this study was to compare 30 days mortality after coronary artery bypass graft (CABG) between cardiac surgery centres, adjusting by confounding risk factors., Methods: All patients, aged 15-99 years, undergoing a CABG intervention after 1st January 2002 in 82 participating centres were eligible for this observational longitudinal study. For each patient, data on severity and risk factors were collected (type of procedure, haemodynamic condition, co-morbidities, recent myocardial infarction and unstable angina, ventricular function, emergency condition, vital status at 30 days). Using a multiple logistic regression analysis the best predictive model was developed for risk-adjustment; a cross-validation procedure was applied; specific risk adjusted mortality rates (RAMR) were estimated. The overall study population was used as reference standard., Results: 34,310 isolated CABG were performed in 64 of the 82 participating centres. Thirty days mortality resulted 2.61%, ranging from 0.33 to 7.63%; eight centres presented a RAMR significantly lower and seven significantly higher than the reference., Conclusions: The study provides valid measures of the heterogeneity between outcomes of the Italian cardiac surgery centres, to support decision-making by NHS management and individual patients. Although not statistically significant, RAMR dropped from year 2002 to 2004 (2.8-2.4%) suggesting that this comparative outcome assessment can contribute to the improvement of performances in cardiac surgery.

Aim: Aim of the study was to evaluate if brain natriuretic peptide (BNP) levels, a cardiac neurohormone well correlated with prognosis in chronic heart failure (CHF), are associated with enhanced ventilatory response to exercise, in ambulatory patients with intermediate peak oxygen uptake (PVO2)., Methods: Resting BNP was measured in 129 consecutive stable CHF patients with mild to moderate heart failure (90% New York Heart Association (NYHA) class II or III) and intermediate (10-18 mL/kg/min) PVO2, assessed during cardiopulmonary exercise test. Mean (SD) left ventricular ejection fraction (EF) and pulmonary systolic pressure (PAP) were 41 +/- 3% and 47 +/- 14 mmHg, respectively. The enhanced ventilatory response to exercise (EVR) was assessed as a slope of the relation between minute ventilation and carbon dioxide production (VE/VCO2 slope) > 35., Results: Thirty-three over 129 patients (26%) had EVR. Mean BNP plasma level was 394 +/- 347 pg/mL. A significant correlation between BNP and EVR (r = 0.310; p < 0.01), was observed. In the logistic multivariate model, a BNP plasma level > 100 pg/mL had an independent predictive value for EVR (95% IC 1.68 to 10.5, Odds Ratio 4.23, p = 0.02). We found a significant correlation between BNP and PAP (r = 0.390; p < 0.001), and between PAP and EVR (r = 0.511; p < 0.01)., Conclusions: In CHF patients with intermediate PVO2, plasma BNP is clearly related to the enhanced ventilatory response to exercise. In this subset, BNP levels could represent an effective alternative tool for the clinical assessment in patients with unreliable cardiopulmonary exercise test.

Background: The assessment of the burden of disease (BOD) is necessary for sensibly allocating limited health-related resources. No such assessment is available currently for Italy., Methods: Global burden of disease (GBD) methods were used to analyse in detail the years of life lost (YLLs) component of BOD for the most important diseases contributing to premature mortality in Italy in 1998. YLLs were computed with and without age-weighting and discounting. YLLs were also analysed by gender, for Italy vs. the Euro-A region (a group of 26 European countries) defined in the 2000 update of the GBD Study, and for northern, central and southern Italy, the three traditionally demarcated regions of the country., Results: The use of YLLs yields a ranking of diseases by their relative contribution to mortality burden which differs from a ranking based purely on death counts. Although males contributed 58.5% and females 41.5% of the total mortality burden in terms of YLLs, using death counts the percentages for males and females were similar (50.6% M, 49.4% F). The leading cause of mortality burden, both in terms of YLLs and death counts, was ischaemic heart disease, followed by stroke and lung cancer. Several other conditions, however, had rankings that varied depending on the measure used. While cardiovascular diseases accounted for 31.7% and 'all cancers' for 34.1% of YLLs, they were responsible, respectively, for 44.7 and 27.9% of death counts. The results for Italy generally corresponded with those obtained in GBD 2000 for EURO-A, but the proportion of the total mortality burden explained by the four leading causes is higher in Italy. For within Italy comparisons, there was a decreasing trend from north to south for 'all cancers' and for several specific cancers. Conversely, a consistent increase in YLL rates from north to south was observed for stroke and hypertensive disease., Conclusions: This analysis of Italy's mortality burden represents the first phase in identifying Italy's total BOD. Simply establishing death counts and rates is no longer sufficient for a full understanding of a country's health status.