Machine learning for the automatic assessment of aortic rotational flow and wall shear stress from 4D flow cardiac magnetic resonance imaging.

OBJECTIVE: Three-dimensional (3D) time-resolved phase-contrast cardiac magnetic resonance (4D flow CMR) allows for unparalleled quantification of blood velocity. Despite established potential in aortic diseases, the analysis is time-consuming and requires expert knowledge, hindering clinical application. The present research aimed to develop and test a fully automatic machine learning-based pipeline for aortic 4D flow CMR analysis. METHODS: Four hundred and four subjects were prospectively included. Ground-truth to train the algorithms was generated by experts. The cohort was divided into training (323 patients) and testing (81) sets and used to train and test a 3D nnU-Net for segmentation and a Deep Q-Network algorithm for landmark detection. In-plane (IRF) and through-plane (SFRR) rotational flow descriptors and axial and circumferential wall shear stress (WSS) were computed at ten planes covering the ascending aorta and arch. RESULTS: Automatic aortic segmentation resulted in a median Dice score (DS) of 0.949 and average symmetric surface distance of 0.839 (0.632-1.071) mm, comparable with the state of the art. Aortic landmarks were located with a precision comparable with experts in the sinotubular junction and first and third supra-aortic vessels (p = 0.513, 0.592 and 0.905, respectively) but with lower precision in the pulmonary bifurcation (p = 0.028), resulting in precise localisation of analysis planes. Automatic flow assessment showed excellent (ICC > 0.9) agreement with manual quantification of SFRR and good-to-excellent agreement (ICC > 0.75) in the measurement of IRF and axial and circumferential WSS. CONCLUSION: Fully automatic analysis of complex aortic flow dynamics from 4D flow CMR is feasible. Its implementation could foster the clinical use of 4D flow CMR. KEY POINTS: • 4D flow CMR allows for unparalleled aortic blood flow analysis but requires aortic segmentation and anatomical landmark identification, which are time-consuming, limiting 4D flow CMR widespread use. • A fully automatic machine learning pipeline for aortic 4D flow CMR analysis was trained with data of 323 patients and tested in 81 patients, ensuring a balanced distribution of aneurysm aetiologies. • Automatic assessment of complex flow characteristics such as rotational flow and wall shear stress showed good-to-excellent agreement with manual quantification.

Echocardiographic assessment of COVID19 sequelae in survivors with elevated cardiac biomarkers.

AIMS: We sought to determine, using advanced echocardiography, the prevalence and type of cardiovascular sequelae after COVID19 infection with marked elevation of cardiovascular biomarkers (CVB), and their prognostic implications. METHODS: All patients admitted from March 1st to May 25th, 2020 to a tertiary referral hospital were included. Those with cardiovascular diseases or dead during admission were excluded. Patients with hs-TnI > 45 ng/L, NT-proBNP>300 pg/mL, and D-dimer >8000 ng/mL were matched with COVID controls (three biomarkers within the normal range) based on intensive care requirements and age, and separately analyzed. RESULTS: From 2025 patients, 80 patients with significantly elevated CVB and 29 controls were finally included. No differences in baseline characteristics were observed among groups, but elevated CVB patients were sicker. Follow-up echocardiograms showed no differences among groups regarding LVEF and only slight differences between groups within the normal range. Hs-TnI patients had lower myocardial work and longitudinal strain. The presence of an abnormal echocardiogram was more frequent in the elevated CVB group compared to controls (23.8 vs 10.3%, P = 0.123) but mainly associated with mild abnormalities in deformation parameters. Management did not change in any case and no major cardiovascular events except deep vein thrombosis occurred after a median follow-up of 7 months. CONCLUSION: Minimal abnormalities in cardiac structure and function are observed in COVID19 survivors without previous cardiovascular diseases who presented a significant CVB rise at admission, with no impact on patient management or short-term prognosis. These results do not support a routine screening program after discharge in this population.

The valve uptake index: improving assessment of prosthetic valve endocarditis and updating [18F]FDG PET/CT(A) imaging criteria.

AIMS: Diagnosis of prosthetic valve endocarditis (PVE) by positron emission computed tomography angiography (PET/CTA) is based on visual and quantitative morpho-metabolic features. However, the fluorodeoxyglucose (FDG) uptake pattern can be sometimes visually unclear and susceptible to subjectivity. This study aimed to validate a new parameter, the valve uptake index [VUI, maximum standardized uptake value (SUVmax)-mean standardized uptake value (SUVmean)/SUVmax], designed to provide a more objective indication of the distribution of metabolic activity. Secondly, to re-evaluate the utility of traditionally used PVE imaging criteria and determine the potential value of adding the VUI in the diagnostic algorithm of PVE. METHODS AND RESULTS: Retrospective analysis of 122 patients (135 prosthetic valves) admitted for suspicion of endocarditis, with a conclusive diagnosis of definite (N = 57) or rejected (N = 65) PVE, and who had undergone a cardiac PET/CTA scan as part of the diagnostic evaluation. We measured the VUI and recorded the SUVmax, SUVratio, uptake pattern, and the presence of endocarditis-related anatomic lesions. The VUI, SUVmax, and SUVratio values were 0.54 ± 0.1 vs. 0.36 ± 0.08, 7.68 ± 3.07 vs. 3.72 ± 1.11, and 4.28 ± 1.93 vs. 2.16 ± 0.95 in the 'definite' PVE group vs. the 'rejected' group, respectively (mean ± SD; P < 0.001). A cut-off value of VUI > 0.45 showed a sensitivity, specificity, and diagnostic accuracy for PVE of 85%, 88%, and 86.7% and increased diagnostic ability for confirming endocarditis when combined with the standard diagnostic criteria. CONCLUSIONS: The VUI demonstrated good diagnostic accuracy for PVE, even increasing the diagnostic power of the traditionally used morphometabolic parameters, which also confirmed their own diagnostic performance. More research is needed to assess whether the integration of the VUI into the PVE diagnostic algorithm may clarify doubtful cases and thus improve the diagnostic yield of PET/CTA.

Cost-effectiveness of implantable cardioverter-defibrillators for primary prevention of sudden cardiac death.

INTRODUCTION AND OBJECTIVES: Implantable cardioverter-defibrillators (ICD) are a cost-effective alternative for secondary prevention of sudden cardiac death, but their efficiency in primary prevention, especially among patients with nonischemic heart disease, is still uncertain. METHODS: We performed a cost-effectiveness analysis of ICD plus conventional medical treatment (CMT) vs CMT for primary prevention of cardiac arrhythmias from the perspective of the national health service. We simulated the course of the disease by using Markov models in patients with ischemic and nonischemic heart disease. The parameters of the model were based on the results obtained from a meta-analysis of clinical trials published between 1996 and 2018 comparing ICD plus CMT vs CMT, the safety results of the DANISH trial, and analysis of real-world clinical practice in a tertiary hospital. RESULTS: We estimated that ICD reduced the likelihood of all-cause death in patients with ischemic heart disease (HR, 0.70; 95%CI, 0.58-0.85) and in those with nonischemic heart disease (HR, 0.79; 95%CI, 0.66-0.96). The incremental cost-effectiveness ratio (ICER) estimated with probabilistic analysis was €19 171/quality adjusted life year (QALY) in patients with ischemic heart disease and €31 084/QALY in those with nonischemic dilated myocardiopathy overall and €23 230/QALY in patients younger than 68 years. CONCLUSIONS: The efficiency of single-lead ICD systems has improved in the last decade, and these devices are cost-effective in patients with ischemic and nonischemic left ventricular dysfunction younger than 68 years, assuming willingness to pay as €25 000/QALY. For older nonischemic patients, the ICER was around €30 000/QALY.

Registration-based semi-automatic assessment of aortic diameter growth rate from contrast-enhanced computed tomography outperforms manual quantification.

OBJECTIVES: Manual assessment of aortic diameters on double-oblique reformatted computed tomography angiograms (CTA) is considered the current standard, although the reproducibility for growth rates has not been reported. Deformable registration of CTA has been proposed to provide 3D aortic diameters and growth maps, but validation is lacking. This study aimed to quantify accuracy and inter-observer reproducibility of registration-based and manual assessment of aortic diameters and growth rates. METHODS: Forty patients with ≥ 2 CTA acquired at least 6 months apart were included. Aortic diameters and growth rate were obtained in the aortic root and the entire thoracic aorta using deformable image registration by two independent observers, and compared with the current standard at typical anatomical landmarks. RESULTS: Compared with manual assessment, the registration-based technique presented low bias (0.46 mm), excellent agreement (ICC = 0.99), and similar inter-observer reproducibility (ICC = 0.99 for both) for aortic diameters; and low bias (0.10 mm/year), good agreement (ICC = 0.82), and much higher inter-observer reproducibility for growth rates (root: ICC = 0.96 vs 0.68; thoracic aorta: ICC = 0.96 vs 0.80). Registration-based growth rate reproducibility over a 6-month-long follow-up was similar to that obtained by manual assessment after 2.7 years (LoA = [- 0.01, 0.33] vs [- 0.13, 0.21] mm/year, respectively). Mapping of diameter and growth rate was highly reproducible (ICC > 0.9) in the whole thoracic aorta. CONCLUSIONS: Registration-based assessment of aortic dilation on CTA is accurate and substantially more reproducible than the current standard, even at follow-up as short as 6 months, and provides robust 3D mapping of aortic diameters and growth rates beyond the pre-established anatomic landmarks. KEY POINTS: • Registration-based semi-automatic assessment of progressive aortic dilation on CTA is accurate and substantially more reproducible than the current standard. • The registration-based technique allows robust growth rate assessment at follow-up as short as 6 months, with a similar reproducibility to that obtained by manual assessment at around 3 years. • The use of image registration provides robust 3D mapping of aortic diameters and growth rates beyond the pre-established anatomic landmarks.

Diagnostic value of quantitative parameters for myocardial perfusion assessment in patients with suspected coronary artery disease by single- and dual-energy computed tomography myocardial perfusion imaging.

PURPOSE: To compare performance of visual and quantitative analyses for detecting myocardial ischaemia from single- and dual-energy computed tomography (CT) in patients with suspected coronary artery disease (CAD). METHODS: Eighty-four patients with suspected CAD were scheduled for dual-energy cardiac CT at rest (CTA) and pharmacological stress (CTP). Myocardial CT perfusion was analysed visually and using three parameters: mean attenuation density (MA), transmural perfusion ratio (TPR) and myocardial perfusion reserve index (MPRI), on both single-energy CT and CT-based iodine images. Significant CAD was defined in AHA-segments by concomitant myocardial hypoperfusion identified visually or quantitatively (parameter < threshold) and coronary stenosis detected by CTA. Single-photon emission CT and invasive coronary angiography were used as reference. Perfusion-parameter cut-off values were calculated in a randomly-selected subgroup of 30 patients. RESULTS: The best-performing thresholds for TPR, MPRI and MA were 0.96, 23 and 0.5 for single-energy CT and 0.97, 47 and 0.3 for iodine imaging. For both CT-imaging modalities, TPR yielded the highest area under receiver operating characteristic curve (AUC) (0.99 and 0.97 for single-energy CT and iodine imaging, respectively, in vessel-based analysis) compared to visual analysis, MA and MPRI. Visual interpretation on iodine imaging resulted in higher AUC compared to that on single-energy CT in per-vessel (AUC: 0.93 vs 0.86, respectively) and per-patient (0.94 vs 0.93) analyses. CONCLUSION: Transmural perfusion ratio on both CT-imaging modalities is the best-performing parameter for detecting myocardial ischaemia compared to visual method and other perfusion parameters. Visual analysis on CT-based iodine imaging outperforms that on single-energy CT.

The impact of waiting for intervention on costs and effectiveness: the case of transcatheter aortic valve replacement.

OBJECTIVES: The economic crisis in Europe might have limited access to some innovative technologies implying an increase of waiting time. The purpose of the study is to evaluate the impact of waiting time on the costs and benefits of transcatheter aortic valve replacement (TAVR) for the treatment of severe aortic stenosis. METHODS: This is a cost-utility analysis from the perspective of the Spanish National Health Service. Results of two prospective hospital registries (158 and 273 consecutive patients) were incorporated into a probabilistic Markov model to compare quality adjusted life years (QALYs) and costs for TAVR after waiting for 3-12 months, relative to immediate TAVR. We simulated a cohort of 1000 patients, male, and 80 years old; other patient profiles were assessed in sensitivity analyses. RESULTS: As waiting time increased, costs decreased at the expense of lower survival and loss of QALYs, leading to incremental cost-effectiveness ratios for eliminating waiting lists of about 12,500 € per QALY. In subgroup analyses prioritization of patients for whom higher benefit was expected led to a smaller loss of QALYs. Concerning budget impact, long waiting lists reduced spending considerably and permanently. CONCLUSIONS: A shorter waiting time is likely to be cost-effective (considering commonly accepted willingness-to-pay thresholds in Europe) relative to 3 months or longer waiting periods. If waiting lists are nevertheless seen as unavoidable due to severe but temporary budgetary restrictions, prioritizing patients for whom higher benefit is expected appears to be a way of postponing spending without utterly sacrificing patients' survival and quality of life.

Agreements between Industry and Academia on Publication Rights: A Retrospective Study of Protocols and Publications of Randomized Clinical Trials.

BACKGROUND: Little is known about publication agreements between industry and academic investigators in trial protocols and the consistency of these agreements with corresponding statements in publications. We aimed to investigate (i) the existence and types of publication agreements in trial protocols, (ii) the completeness and consistency of the reporting of these agreements in subsequent publications, and (iii) the frequency of co-authorship by industry employees. METHODS AND FINDINGS: We used a retrospective cohort of randomized clinical trials (RCTs) based on archived protocols approved by six research ethics committees between 13 January 2000 and 25 November 2003. Only RCTs with industry involvement were eligible. We investigated the documentation of publication agreements in RCT protocols and statements in corresponding journal publications. Of 647 eligible RCT protocols, 456 (70.5%) mentioned an agreement regarding publication of results. Of these 456, 393 (86.2%) documented an industry partner's right to disapprove or at least review proposed manuscripts; 39 (8.6%) agreements were without constraints of publication. The remaining 24 (5.3%) protocols referred to separate agreement documents not accessible to us. Of those 432 protocols with an accessible publication agreement, 268 (62.0%) trials were published. Most agreements documented in the protocol were not reported in the subsequent publication (197/268 [73.5%]). Of 71 agreements reported in publications, 52 (73.2%) were concordant with those documented in the protocol. In 14 of 37 (37.8%) publications in which statements suggested unrestricted publication rights, at least one co-author was an industry employee. In 25 protocol-publication pairs, author statements in publications suggested no constraints, but 18 corresponding protocols documented restricting agreements. CONCLUSIONS: Publication agreements constraining academic authors' independence are common. Journal articles seldom report on publication agreements, and, if they do, statements can be discrepant with the trial protocol.

Effectiveness, safety and costs of thromboembolic prevention in patients with non-valvular atrial fibrillation: phase I ESC-FA protocol study and baseline characteristics of a cohort from a primary care electronic database.

PURPOSE: Atrial fibrillation is the most common arrhythmia. Its management aims to reduce symptoms and to prevent complications through rate and rhythm control, management of concomitant cardiac diseases and prevention of related complications, mainly stroke. The main objective of Effectiveness, Safety and Costs in Atrial Fibrillation (ESC-FA) study is to analyse the drugs used for the management of the disease in real-use conditions, particularly the antithrombotic agents for stroke prevention. The aim of this work is to present the study protocol of phase I of the ESC-FA study and the baseline characteristics of newly diagnosed patients with atrial fibrillation in Catalonia, Spain. PARTICIPANTS: The data source is System for the Improvement of Research in Primary Care (SIDIAP) database. The population included are all patients with non-valvular atrial fibrillation diagnosis registered in the electronic health records during 2007-2012. FINDINGS TO DATE: A total of 22,585 patients with non-valvular atrial fibrillation were included in the baseline description. Their mean age was 72.8 years and 51.6% were men. The most commonly prescribed antithrombotics were vitamin K antagonists (40.1% of patients) and platelet aggregation inhibitors (32.9%); 25.3% had not been prescribed antithrombotic treatment. Age, gender, comorbidities and co-medication at baseline were similar to those reported for previous studies. FUTURE PLANS: The next phase in the ESC-FA study will involve assessing the effectiveness and safety of antithrombotic treatments, analysing stroke events and bleeding episodes' rates in our patients (rest of phase I), describing the current management of the disease and its costs in our setting, and assessing how the introduction of new oral anticoagulants changes the stroke prevention in non-valvular atrial fibrillation.

Transfemoral transcatheter aortic valve replacement compared with surgical replacement in patients with severe aortic stenosis and comparable risk: cost-utility and its determinants.

OBJECTIVE: To evaluate cost-effectiveness of transfemoral TAVR vs surgical replacement (SAVR) and its determinants in patients with severe symptomatic aortic stenosis and comparable risk. METHODS: Patients were prospectively recruited in 6 Spanish hospitals and followed up over one year. We estimated adjusted incremental cost-effectiveness ratio (ICER) (Euros per quality-adjusted life-year [QALY] gained) using a net-benefit approach and assessed the determinants of incremental net-benefit of TAVR vs SAVR. RESULTS: We analyzed data on 207 patients: 58, 87 and 62 in the Edwards SAPIEN (ES) TAVR, Medtronic-CoreValve (MC) TAVR and SAVR groups respectively. Average cost per patient of ES-TAVR was €8800 higher than SAVR and the gain in QALY was 0.036. The ICER was €148,525/QALY. The cost of MC-TAVR was €9729 higher than SAVR and the QALY difference was -0.011 (dominated). Results substantially changed in the following conditions: 1) in patients with high preoperative serum creatinine the ICERs were €18,302/QALY and €179,618/QALY for ES and MC-TAVR respectively; 2) a 30% reduction in the cost of TAVR devices decreased the ICER for ES-TAVR to €32,955/QALY; and 3) imputing hospitalization costs from other European countries leads to TAVR being dominant. CONCLUSIONS: In countries with relatively low health care costs TAVR is not likely to be cost-effective compared to SAVR in patients with intermediate risk for surgery, mainly because of the high cost of the valve compared to the cost of hospitalization. TAVR could be cost-effective in specific subgroups and in countries with higher hospitalization costs.

Prevalence, characteristics, and publication of discontinued randomized trials.

IMPORTANCE: The discontinuation of randomized clinical trials (RCTs) raises ethical concerns and often wastes scarce research resources. The epidemiology of discontinued RCTs, however, remains unclear. OBJECTIVES: To determine the prevalence, characteristics, and publication history of discontinued RCTs and to investigate factors associated with RCT discontinuation due to poor recruitment and with nonpublication. DESIGN AND SETTING: Retrospective cohort of RCTs based on archived protocols approved by 6 research ethics committees in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics and planned recruitment from included protocols. Last follow-up of RCTs was April 27, 2013. MAIN OUTCOMES AND MEASURES: Completion status, reported reasons for discontinuation, and publication status of RCTs as determined by correspondence with the research ethics committees, literature searches, and investigator surveys. RESULTS: After a median follow-up of 11.6 years (range, 8.8-12.6 years), 253 of 1017 included RCTs were discontinued (24.9% [95% CI, 22.3%-27.6%]). Only 96 of 253 discontinuations (37.9% [95% CI, 32.0%-44.3%]) were reported to ethics committees. The most frequent reason for discontinuation was poor recruitment (101/1017; 9.9% [95% CI, 8.2%-12.0%]). In multivariable analysis, industry sponsorship vs investigator sponsorship (8.4% vs 26.5%; odds ratio [OR], 0.25 [95% CI, 0.15-0.43]; P < .001) and a larger planned sample size in increments of 100 (-0.7%; OR, 0.96 [95% CI, 0.92-1.00]; P = .04) were associated with lower rates of discontinuation due to poor recruitment. Discontinued trials were more likely to remain unpublished than completed trials (55.1% vs 33.6%; OR, 3.19 [95% CI, 2.29-4.43]; P < .001). CONCLUSIONS AND RELEVANCE: In this sample of trials based on RCT protocols from 6 research ethics committees, discontinuation was common, with poor recruitment being the most frequently reported reason. Greater efforts are needed to ensure the reporting of trial discontinuation to research ethics committees and the publication of results of discontinued trials.

Patterns of use and effectiveness of early invasive strategy in non-ST-segment elevation acute coronary syndromes: an assessment by propensity score.

BACKGROUND: The patterns of use and the benefit of an early invasive strategy (EIS) in patients with non-ST-segment elevation acute coronary syndrome in a real-life population are not well established. METHODS: All consecutive patients hospitalized because of non-ST-segment elevation acute coronary syndrome between November 2004 and June 2005 in 32 randomly selected hospitals were prospectively included. Patients were stratified by their baseline risk profile using the Global Registry of Acute Coronary Events (GRACE) risk score in 2 groups. Inhospital mortality and 1- and 6-month mortality or rehospitalization for acute coronary syndromes were analyzed. To ensure optimal adjustment propensity score, conventional logistic regression and Cox regression were used. RESULTS: Of 2,856 patients analyzed, 1,616 (56%) had low/intermediate risk (GRACE140). Patients who underwent EIS had lower risk than those who did not (GRACE score 128.2+/-41 vs 138.5+/-43, P<.001). Coronary angiography facility emerged as the strongest predictor of EIS (odds ratio [OR] 13.7 [95% CI 7.1-25]). Patients who underwent EIS had lower rate of the 6-month outcome in both the whole population (9% [95% CI 6.6-11.9] vs 14% [95% CI 12.5-15.6], P=.003) and in high-risk patients (16.5% [95% CI 11-23] vs 23.6% [95% CI 20.8-26.5], P=.04). However, this benefit of EIS was not apparent after statistical adjustment in the whole population (OR 0.8, CI 0.55-1.1, P=.17) or in high-risk patients (OR 0.7, CI 0.46-1.1, P=.16). CONCLUSIONS: In a real-life population, EIS was mainly performed in patients of low/intermediate risk. An obvious benefit of this strategy could not be found.

Outcomes in off-pump vs. on-pump coronary artery bypass grafting stratified by pre-operative risk profile: an assessment using propensity score.

AIMS: To assess the benefit of off-pump coronary surgery stratified by the pre-operative risk profile. METHODS AND RESULTS: Prospective and multicentric cohort study. All consecutive patients undergoing a first coronary bypass procedure between November 2001 and November 2003 were potentially eligible. Pre-operative EuroSCORE and in-hospital outcomes were prospectively collected using strictly standardized criteria. To ensure optimal adjustment, a propensity score was constructed using clinically relevant variables and incorporating individual centres. Of 1602 patients who underwent a first coronary bypass, EuroSCORE could be calculated in 1585: 787 were of moderate/high pre-operative risk profile (EuroSCORE > 3), of which 347 underwent off-pump procedures, and 798 were of low pre-operative risk profile (EuroSCORE < or = 3), of which 349 underwent off-pump procedures. After risk adjusting for propensity score, off-pump patients had less major events (post-operative death, myocardial infarction, and need for reoperation). This benefit was higher in the low-risk stratum (OR ranged between 0.27 and 0.4; P = 0.02-0.07) than in the high-risk stratum (OR between 0.4 and 0.7; P, not significant). CONCLUSION: In real-life conditions, off-pump coronary surgery may be more effective than on-pump surgery. In contrast with previous reports, our results suggest that this benefit may be higher in patients with low pre-operative risk.

[Evaluation of risk-adjusted hospital mortality after coronary artery bypass graft surgery in the Catalan public healthcare system. Influence of hospital management type (ARCA Study)]. / Evaluación de la mortalidad hospitalaria ajustada al riesgo de la cirugía coronaria en la sanidad pública catalana. Influencia del tipo de gestión del centro (estudio ARCA).

INTRODUCTION AND OBJECTIVES: Previous studies suggest that the effectiveness of coronary surgery is influenced by the type of management at the healthcare centre where the intervention is performed. The present study assessed the risk-adjusted hospital mortality of coronary surgery in the Catalan healthcare system in hospitals under either private or public management. METHODS: We carried out a prospective study of all consecutive patients receiving a first coronary artery bypass graft, with public financial support, in a period of 2 years at 5 hospitals under either public or private management. Preoperative risk was assessed using the EuroSCORE and Catalan Agency for Health Technology Assessment (CAHTA) predictive models. RESULTS: Overall, 1605 patients underwent interventions, 21% of which were at private hospitals. The percentage of patients undergoing non-elective surgery was higher at private hospitals (64% vs 50%), as was the percentage needing intravenous nitrates (17% vs 11%) and the percentage in functional class IV (20% vs 11%). The odds ratio for in-hospital mortality in private compared with public hospitals was 0.56 (95% CI, 0.29-1.06) when adjusted for EuroSCORE, 0.56 (95% CI, 0.29-1.07) when adjusted for CAHTA score, and 0.43 (95% CI, 0.21-0.87) when adjusted for patient characteristics. The mortality observed, 4.8% (95% CI 3.8-5.6), was not significantly higher than that predicted. CONCLUSIONS: a) Hospital mortality was equivalent to or lower than that expected after adjustment for the 2 risk scores; b) after adjustment for baseline patient characteristics, the results favored privately managed centers; and c) comparison with previous results suggests that coronary surgery effectiveness has improved in recent years.