ABC | Volume 114, Nº3, March 2020

Short Editorial Prognostic Scores for Mortality in Cardiac Surgery for Infective Endocarditis Alexandre Bahia Barreiras Martins 1 and Cristiane da Cruz Lamas 2,3, 4 Unidade Cardiointensiva - Clínica São Vicente da Gávea, 1 Rio de Janeiro, RJ -Brazil Coordenação de Ensino e Pesquisa - Instituto Nacional de Cardiologia, 2 Rio de Janeiro, RJ - Brazil Escola de Ciências da Saúde - Universidade do Grande Rio (Unigranrio), 3 Rio de Janeiro, RJ - Brazil Centro Hospitalar - Instituto Nacional de Infectologia Evandro Chagas - Fiocruz, 4 Rio de Janeiro, RJ – Brazil Short Editorial related to the article: Analysis of Risk Scores to Predict Mortality in Patients Undergoing Cardiac Surgery for Endocarditis Mailing Address: Cristiane da Cruz Lamas • Instituto Nacional de Cardiologia - Coordenação de Ensino e Pesquisa - Rua das Laranjeiras, 374 5º andar. Postal Code 22240-006, Rio de Janeiro, RJ – Brazil Email: cristianelamas@gmail.com Keywords Endocarditis/surgery; Hospital Mortality; Cardiac Surgery/ mortalidade; Prognosis; Scores. The article by Pivatto F Jr et al. 1 allows us to discuss the important issue of prognostic scores in patients who have cardiac surgery for infective endocarditis (IE). 1 The management of left- sided IE often involves surgery during the index admission, and the main challenge is to rapidly and correctly identify patients at high risk and to transfer them to institutions with a surgical team with expertise in endocarditis surgery. Prognostic scores are important for several reasons: a reasonable estimate of the risk of death is important in clinical decision-making regarding surgical indication; the estimate is necessary to inform patients and their families of the surgical risk; risk stratification permits a fair comparison of cardiac surgery results, so that surgeons and hospitals treating high-risk patients will not appear to have worse results than others. 2 For operative mortality to remain a valid measure of quality of care, it must be related to the risk profile of the patients receiving surgery. 2 Euroscore I, published in 1999, evaluated 19,030 patients submitted to cardiac surgery in 8 countries in Europe, studying 97 risk factors for death, and among those, the ones that significantly affected surgical prognosis were selected. 2 These variables are presented in Table 1. In this study, only 30% were submitted to valve surgery, and the number of individuals who had endocarditis is not mentioned. 2 Euroscore II, published in 2012, 3 had the goal of updating the first model by evaluating 22,381 patients from 43 countries in the world, including sites outside Europe, so as to create a more reliable score, incorporating new variables and adjusting others (Table 1). At this time, it was already known that the Euroscore 2 superestimated the surgical risk as technical progress in cardiac surgery along the previous decade had been made, with a mortality decrease adjusted by risk. Improvements to Euroscore were: creatinine clearance as a better measure of renal function than serum creatinine values; unstable angina defined by the use of intravenous nitrates was outdated; weight of intervention was not properly assessed in the previous model (for example, aortic valve replacement with or without concurrent coronary artery bypass grafting had the same weight) and some continuous variables, such as number of previous cardiac surgeries and pulmonary artery systolic pressures were treated as a dichotomic variable. 3 The receiving operator curve (ROC) of the scores showed an area under the curve (AUC) of 0.78 for the logistic and additive Euroscore and of 0.80 for Euroscore II. A criticism to the model is, that although non-European countries were included, the vast majority of patients were from Spain, France, Italy and the United Kingdom, who contributed with 19, 16, 15 and 12 sites respectively. 3 As for Latin America, Brazil contributed with data from 4 centers, Argentina 1 and Uruguay 1. Also, the model did not analyze valve surgery separately. In fact, only 2.2% of patients (497 in absolute numbers) with active IE had been included. 4 A limitation outlined in the study was that all centers participated voluntarily, what introduces selection bias to the data. 3 Patients with IE must be thoroughly assessed. If we consider the usual profile of a patient with IE who is operated at Instituto Nacional de Cardiologia, for example, he or she will have a serum creatinine above normal, scoring 2 points; active disease (under antibiotic treatment for IE at the time of surgery), scoring 3 points, and at least moderate left ventricular dysfunction, scoring 1, that is, with a total Euroscore of 6 and anticipated mortality of over 11%. Not infrequently, this patient previously had cardiac surgery (as over a third have rheumatic valvopathy and about 10% previously had IE), which adds 3 points to the total score. 4-6 Therefore, Euroscore I does not discriminate well this subset of patients, as most will probably fall into the 6+ score. Patrat-Delon et al., 7 studying 149 patients operated for IE in France, between 2002 and 2013, of which in-hospital mortality was 21%, came to a similar conclusion regarding EuroSCORE II: it underestimated mortality in patients with predicted mortality over 10%. 7 The Society of Thoracic Surgeons–Infective Endocarditis (STS-IE) score, published in 2011, 8 has its variables shown schematically in Table 1. In the subset of North American patients with IE studied in its development, of the 13,617 patients, only over half had active endocarditis at the time of surgery. 8 Overall mortality was 8.2%, although multiple valve surgery had an operative mortality of 13%. Postoperative complications were present in more than half the patients, most common of which were prolonged ventilation in over a quarter. DOI: https://doi.org/10.36660/abc.20200070 525