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BACKGROUND: Bleeding into the chest is a life-threatening complication of cardiac surgery. Blood transfusion has been implicated as an important cause of harm associated with bleeding, based largely on studies demonstrating an independent association between transfusion and mortality. These studies did not, however, consider the possibility that bleeding may in itself be harmful, inasmuch as drains are inefficient at clearing blood from the chest and retained blood may compromise cardiac and lung function. STUDY DESIGN AND METHODS: We undertook a multivariate logistic regression analysis of the risk factors associated with mortality in 2599 consecutive patients undergoing cardiac surgery. Unlike previous studies the risk factors examined included the volume of chest tube drainage at 24 hours. A stratified analysis was also undertaken that compared the adjusted risk of death for patients exposed or not exposed to a postoperative blood transfusion. RESULTS: Blood transfusion was not an independent predictor of mortality (p = 0.4). Chest tube drainage was the strongest independent predictor of mortality (p < 0.001). In the stratified analysis, chest tube drainage remained an independent predictor of mortality for patients not exposed to a blood transfusion (p < 0.01). Furthermore, the risk of death of these patients was no different from patients exposed to a blood transfusion (p = 0.7 for interaction). CONCLUSIONS: Our results argue that for patients undergoing cardiac surgery bleeding contributes to mortality through mechanisms unrelated to blood transfusion. [ABSTRACT FROM AUTHOR]

Background: Reoperative coronary artery bypass grafting (redo CABG) shows improving outcomes, but with varying degrees of improvement. We assessed contemporary outcomes after redo CABG to determine if redo status is still a risk factor for early postoperative complications and midterm survival. Methods: Isolated CABG procedures (June 1, 2001 to May 31, 2008) within the Australasian Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database were included. Redo status as a predictor for early outcomes was assessed with logistic regression analysis. Midterm survival was determined from the National Death Index. Effect of redo status on midterm survival was assessed using a Cox proportional hazards model. Results: Inclusion criteria were met by 13,436 patients, and 458 (3.4%) underwent redo CABG. Operative mortality was 4.8% for redo CABG and 1.8% for first-time CABG (p < 0.001). After adjustment, redo status remained a predictor for operative mortality (odds ratio [OR], 2.1; 95% confidence interval [CI], 1.3 to 3.6), myocardial infarction (OR, 2.8; 95% CI, 1.6 to 6.0), and prolonged ventilation (OR, 1.5; 95% CI, 1.1 to 2.0). Unadjusted survival was lower for the redo CABG group vs the first-time CABG group at up to 6 years (p = 0.01, log-rank test. After adjusting for differences in patient variables, redo status was not a predictor of midterm survival (OR, 1.03; 95% CI, 0.78 to 1.35; p = 0.85). Conclusions: Early postoperative outcomes of redo CABG are encouraging. Midterm survival is excellent; however, redo remains a significant risk factor for operative mortality in contemporary practice. [Copyright &y& Elsevier]

The purpose of the present paper was to assess the performance of the European system for cardiac operative risk evaluation (EuroSCORE) model in an Australian adult cardiac surgical population. The additive and logistic EuroSCORE models were retrospectively applied to predict operative mortality in 2106 consecutive patients undergoing cardiac surgery at St Vincent's Hospital, Melbourne between June 2001 and August 2003, and at Geelong Hospital between June 2001 and April 2004. The entire cohort and a subset of patients undergoing isolated coronary artery bypass graft (CABG) surgery were analysed. Model discrimination and calibration was tested by determining the area under the receiver operating characteristic (ROC) curve and Hosmer−Lemeshowχ2, respectively. There were significant differences in the prevalence of risk factors between the Australian and European cardiac surgical populations. There were 81 deaths (observed mortality 3.85%) in the entire cohort and 39 deaths in the isolated CABG group (observed mortality 2.60%). The EuroSCORE models overestimated mortality (entire cohort: additive predicted 5.75%, logistic predicted 9.93%; isolated CABG: additive predicted 4.87%, logistic predicted 7.71%). Discriminative power was very good for the entire cohort (area under ROC curve, 0.81 (additive) and 0.82 (logistic)). Calibration of both models was poor. The additive and logistic EuroSCORE model of risk prediction was not validated in the present population of cardiac surgical patients. The models may not accurately predict outcomes of patients undergoing cardiac surgery in Australia. [ABSTRACT FROM AUTHOR]

Background: Prosthesis-patient mismatch (PPM) occurs when the valve prosthesis implanted at surgery is too small in relation to patient''s body size, causing high transvalvular gradients. We investigated if severe PPM is related to early morbidity and mortality after aortic valve replacement (AVR). Methods: We analysed prospectively collected data of 701 consecutive patients undergoing AVR between June 2001 and February 2006 at two Australian public hospitals. The indexed valve effective orifice area (IEOA) was estimated for each valve prosthesis implanted. PPM was defined as ≤0.65cm2 m−2. PPM was correlated with operative mortality, stroke, prolonged ventilation, new renal failure, prolonged intensive care stay, prolonged hospital stay and readmission to hospital within 30 days by univariate and multivariate methods. Results: PPM was present in 6.6% of patients. Overall operative mortality was 4.1%. Isolated AVR was performed in only 38.4% of patients. For patients with PPM, the univariate and multivariate odds ratio for mortality were 5.2 (P =0.002) and 6.1 (P =0.006), respectively. The other multivariate predictors of mortality were age, pre-operative serum creatinine, emergency status, pulmonary artery pressure and bypass time. PPM was not associated with stroke, prolonged ventilation, new renal failure, prolonged intensive care or hospital stay, or readmission within 30 days. Conclusion: PPM was associated with increased operative mortality. PPM should be avoided where possible as it may reduce operative mortality following AVR. [Copyright &y& Elsevier]

Abstract: Objective: There is an important role for accurate risk prediction models in current cardiac surgical practice. Such models enable benchmarking and allow surgeons and institutions to compare outcomes in a meaningful way. They can also be useful in the areas of surgical decision-making, preoperative informed consent, quality assurance and healthcare management. The aim of this study was to assess the performance of the European System for Cardiac Operative Risk Evaluation (EuroSCORE) model on the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) patient database. Methods: The additive and logistic EuroSCORE models were applied to all patients undergoing cardiac surgery at six institutions in the state of Victoria between 1st July 2001 and 4th July 2005 within the ASCTS database who have complete data. The entire cohort and a subgroup of patients undergoing coronary artery bypass grafting (CABG) only were analysed. Observed and predicted mortalities were compared. Model discrimination was tested by determining the area under the receiver operating characteristic (ROC) curve. Model calibration was tested by the Hosmer–Lemeshow chi-square test. Results: Eight thousand three hundred and thirty-one patients with complete data were analysed. There were significant differences in the prevalence of risk factors between the ASCTS and European cardiac surgical populations. Observed mortality was 3.20% overall and 2.00% for the CABG only group. The EuroSCORE models over estimated mortality (entire cohort: additive predicted 5.31%, logistic predicted 8.76%; CABG only: additive predicted 4.25%, logistic predicted 6.19%). Discriminative power of both models was very good. Area under ROC curve was 0.83 overall and 0.82 for the CABG only group. Calibration of both models was poor as mortality was over predicted at nearly all risk deciles. Hosmer–Lemeshow chi-square test returned P-values less than 0.05. Conclusions: The additive and logistic EuroSCORE does not accurately predict outcomes in this group of cardiac surgery patients from six Australian institutions. Hence, the use of the EuroSCORE models for risk prediction may not be appropriate in Australia. A model, which accurately predicts outcomes in Australian cardiac surgical patients, is required. [Copyright &y& Elsevier]

Objectives: Controversy continues over the optimal revascularisation strategy for patients with multi-vessel coronary artery disease. Clinical characteristics, risk profile, and mortality of patients undergoing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) are thought to differ but there are limited contemporary comparative data. Methods: We compared clinical characteristics, in-hospital and 30-day mortality of 3841 consecutive patients undergoing isolated CABG and 4417 undergoing PCI. Independent predictors of 30-day mortality were determined by multiple logistic regression analysis. Results: CABG patients were older (p <0.01). The CABG group had a higher incidence of diabetes, heart failure, left ventricular ejection fraction <45%, multi-vessel coronary artery, peripheral vascular and cerebro-vascular disease (all p <0.01). Patients undergoing PCI had a higher incidence of recent myocardial infarction (MI) as the indication for revascularisation (p <0.01). In-hospital and 30-day mortality was 1.8% and 1.7% in the CABG group, and 1.4% and 1.8% in the PCI group, respectively. Independent predictors of 30-day mortality after CABG were age (odds ratio 1.1 per year, 95% confidence interval 1.0–1.1), cardiogenic shock (4.10, 1.7–10.5) and previous CABG (6.6, 2.4–17.7). Predictors after PCI were diabetes (2.7, 1.4–5.1), female gender (3.0, 1.6–5.5), renal failure (3.2, 1.2–8.0), MI<24h (4.0, 2.2–7.6), left main intervention (5.4, 1.0–27.7), heart failure (6.0, 2.6–14.0) and cardiogenic shock (11.7, 5.4–25.2). Conclusions: In contemporary clinical practice, CABG is preferred in patients with multi-vessel coronary and associated non-coronary vascular disease, while PCI is the dominant strategy for acute MI. Despite this, in-hospital and 30-day mortality rates were similar. Predictors of early mortality after CABG differ to those of PCI. [Copyright &y& Elsevier]