Maurício de Nassau Machado

Prognostic value of acute kidney injury after cardiac surgery according to kidney disease: improving global outcomes definition and staging (KDIGO) criteria.

Objectives The definition of acute renal failure has been recently reviewed, and the term acute kidney injury (AKI) was proposed to cover the entire spectrum of the syndrome, ranging from small changes in renal function markers to dialysis needs. This study was aimed to evaluate the incidence, morbidity and mortality associated with AKI (based on KDIGO criteria) in patients after cardiac surgery (coronary artery bypass grafting or cardiac valve surgery) and to determine the value of this feature as a predictor of hospital mortality (30 days). Methods From January 2003 to June 2013, a total of 2,804 patients underwent cardiac surgery in our service. Cox proportional hazard models were used to determine the association between the development of AKI and 30-day mortality. Results A total of 1,175 (42%) patients met the diagnostic criteria for AKI based on KDIGO classification during the first 7 postoperative days: 978 (35%) patients met the diagnostic criteria for stage 1 while 100 (4%) patients met the diagnostic criteria for stage 2 and 97 (3%) patients met the diagnostic criteria for stage 3. A total of 63 (2%) patients required dialysis treatment. Overall, the 30-day mortality was 7.1% (2.2%) for patients without AKI and 8.2%, 31% and 55% for patients with AKI at stages 1, 2 and 3, respectively. The KDIGO stage 3 patients who did not require dialysis had a mortality rate of 41%, while the mortality of dialysis patients was 62%. The adjusted Cox regression analysis revealed that AKI based on KDIGO criteria (stages 1–3) was an independent predictor of 30-day mortality (P<0.001 for all. Hazard ratio = 3.35, 11.94 and 24.85). Conclusion In the population evaluated in the present study, even slight changes in the renal function based on KDIGO criteria were considered as independent predictors of 30-day mortality after cardiac surgery.

Effects of the use of mechanical ventilation weaning protocol in the Coronary Care Unit: randomized study

OBJECTIVE To compare mechanical ventilation weaning based on a protocol using the spontaneous breathing trial against mechanical ventilation weaning without a standardized protocol in heart patients. METHODS Prospective, open, randomized study. In 2006, 36 patients undergoing mechanical ventilation for over 24 hours were randomized into two groups: control group - eighteen patients whose mechanical ventilation weaning was performed according to the different procedures adopted by the multidisciplinary team; and experimental group - eighteen patients weaned according to previously established protocol. RESULTS Control group patients started the weaning process sooner than experimental group patients (74.7 ± 14.7 hours vs. 185.7 ± 22.9 hours, P=0.0004). However, after the experimental group patients were ready for weaning, the extubation was carried out more rapidly than in the control group (149.1 ± 3.6 min vs. 4179.1 ± 927.8 min, P < 0.0001) with significantly lower reintubation rates (16.7% vs. 66.7%, P = 0.005). CONCLUSION The use of a specific protocol based on the spontaneous breathing trial for mechanical ventilation weaning in heart patients had better outcomes than weaning carried out without a standardized protocol, with shorter weaning times and lower reintubation rates.

Elevated Troponin Levels after Prolonged Supraventricular Tachycardia in Patient with Normal Coronary Angiography

The European Society of Cardiology and the American College of Cardiology redefined the concept of myocardial infarction in the presence of highly positive markers of myocardial injury associated with at least one of the following: ischemic symptoms; development of pathologic Q waves on the ECG or ECG changes indicative of ischemia (positive or negative deviation of the ST segment), making troponins one of the most important aspects in the evaluation and stratification of patients with chest pain in the emergency room. However, although troponin gives excellent accuracy in the identification of myocardial necrosis, it is known that it can also be elevated in a series of nonatherosclerotic heart diseases. We present the case of a 49-year-old female patient admitted to the Chest Pain Unit with a history of supraventricular tachycardia associated with chest discomfort, nausea and diaphoresis. During risk stratification, the patient presented with a high serum troponin T level (0.143 ng/ml) but with a normal coronary angiography.

Prevalence of Chlamydia Pneumoniae and Mycoplasma Pneumoniae in different forms of coronary disease

Irineu Luiz Maia1,2, José Carlos Nicolau3, Maurício de Nassau Machado1,2, Lília Nigro Maia1,2, Isabela Thomaz Takakura2, Paulo Ricardo de Fernando Rocha2, José Antônio Cordeiro1, José Antônio Franchini Ramires3 Faculdade de Medicina de São José do Rio Preto (Famerp)1, Hospital de Base de São José do Rio Preto2, Instituto do Coração Faculdade de Medicina da Universidade de São Paulo (InCor USP)3, São José do Rio Preto, SP; São Paulo, SP BrasilBACKGROUND Several infectious agents have been investigated since the association between atherosclerosis and infection was demonstrated; however, the results of these studies are contradictory. OBJECTIVE To test the association between serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in different forms of acute coronary syndromes (ACS). METHODS One hundred and twenty-six patients were divided in 4 groups: ACS with ST-segment elevation (32 patients), ACS without ST-segment elevation (30 patients), chronic coronary artery disease (30 patients) and blood donors without known coronary disease (34 patients--control group). In the two first groups, serum samples were collected at hospital admission (first 24 hours of hospitalization) and after a 6-month follow-up. In the other two groups, only a basal sample was collected. Anti-Chlamydia and anti-Mycoplasma antibodies were measured by indirect immunofluorescence in all samples. RESULTS Significant differences were observed between the basal sample and the one measured after a 6-month follow-up in patients with myocardial infarction with ST-segment elevation for Chlamydia (650+/-115.7 versus 307+/-47.5, p=0.0001) as well as Mycoplasma (36.5+/-5.0 versus 21.5+/-3.5, p=0.0004). The groups with ACS had higher anti-Chlamydia and anti-Mycoplasma serum antibody levels in the basal measurement, when compared to the patients with chronic coronary disease and the control group, but the differences were not statistically significant. CONCLUSION The present study showed an association between the serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in the acute phase of patients with unstable angina or myocardial infarction.

Predicting reintubation, prolonged mechanical ventilation and death in post-coronary artery bypass graft surgery: a comparison between artificial neural networks and logistic regression models.

Introduction In coronary artery bypass (CABG) surgery, the common complications are the need for reintubation, prolonged mechanical ventilation (PMV) and death. Thus, a reliable model for the prognostic evaluation of those particular outcomes is a worthwhile pursuit. The existence of such a system would lead to better resource planning, cost reductions and an increased ability to guide preventive strategies. The aim of this study was to compare different methods – logistic regression (LR) and artificial neural networks (ANNs) – in accomplishing this goal. Material and methods Subjects undergoing CABG (n = 1315) were divided into training (n = 1053) and validation (n = 262) groups. The set of independent variables consisted of age, gender, weight, height, body mass index, diabetes, creatinine level, cardiopulmonary bypass, presence of preserved ventricular function, moderate and severe ventricular dysfunction and total number of grafts. The PMV was also an input for the prediction of death. The ability of ANN to discriminate outcomes was assessed using receiver-operating characteristic (ROC) analysis and the results were compared using a multivariate LR. Results The ROC curve areas for LR and ANN models, respectively, were: for reintubation 0.62 (CI: 0.50–0.75) and 0.65 (CI: 0.53–0.77); for PMV 0.67 (CI: 0.57–0.78) and 0.72 (CI: 0.64–0.81); and for death 0.86 (CI: 0.79–0.93) and 0.85 (CI: 0.80–0.91). No differences were observed between models. Conclusions The ANN has similar discriminating power in predicting reintubation, PMV and death outcomes. Thus, both models may be applicable as a predictor for these outcomes in subjects undergoing CABG.

Prevalência de Chlamydia Pneumoniae e Mycoplasma Pneumoniae em diferentes formas da doença coronariana

Irineu Luiz Maia1,2, José Carlos Nicolau3, Maurício de Nassau Machado1,2, Lília Nigro Maia1,2, Isabela Thomaz Takakura2, Paulo Ricardo de Fernando Rocha2, José Antônio Cordeiro1, José Antônio Franchini Ramires3 Faculdade de Medicina de São José do Rio Preto (Famerp)1, Hospital de Base de São José do Rio Preto2, Instituto do Coração Faculdade de Medicina da Universidade de São Paulo (InCor USP)3, São José do Rio Preto, SP; São Paulo, SP BrasilBACKGROUND Several infectious agents have been investigated since the association between atherosclerosis and infection was demonstrated; however, the results of these studies are contradictory. OBJECTIVE To test the association between serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in different forms of acute coronary syndromes (ACS). METHODS One hundred and twenty-six patients were divided in 4 groups: ACS with ST-segment elevation (32 patients), ACS without ST-segment elevation (30 patients), chronic coronary artery disease (30 patients) and blood donors without known coronary disease (34 patients--control group). In the two first groups, serum samples were collected at hospital admission (first 24 hours of hospitalization) and after a 6-month follow-up. In the other two groups, only a basal sample was collected. Anti-Chlamydia and anti-Mycoplasma antibodies were measured by indirect immunofluorescence in all samples. RESULTS Significant differences were observed between the basal sample and the one measured after a 6-month follow-up in patients with myocardial infarction with ST-segment elevation for Chlamydia (650+/-115.7 versus 307+/-47.5, p=0.0001) as well as Mycoplasma (36.5+/-5.0 versus 21.5+/-3.5, p=0.0004). The groups with ACS had higher anti-Chlamydia and anti-Mycoplasma serum antibody levels in the basal measurement, when compared to the patients with chronic coronary disease and the control group, but the differences were not statistically significant. CONCLUSION The present study showed an association between the serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in the acute phase of patients with unstable angina or myocardial infarction.

Ultrafiltração convencional com modificação técnica no tratamento cirúrgico dos defeitos cardíacos congênitos

Objective: To compare patients submitted to conventional ultrafiltration (CUF) with and without a technical modification that allows the use of residual blood from the circuit tubes and oxygenator. Method: From March 2002 to January 2005, 301 patients undergoing congenital heart defect surgery with cardiopulmonary bypass (CPB) were retrospectively analyzed and divided into two groups: Group A - 130 submitted to CUF and Group B, 171 patients submitted to CUF with a technical modification that uses residual blood. Demographic data, diagnosis, surgical treatment, intra-operative and postoperative data, the need and amount of blood transfusions, laboratorial results and length of hospital stay were compared between the groups. Results: There was no differences in the initial hematocrit before CPB (p = 0.06), but in Group B, the values after ultrafiltration were higher (p <0.0001). Group B patients received more transfusions in the first 48 hours of the postoperative period (p <0.0001). There was no significant difference in the time of mechanical ventilation (p = 0.34), but the inotropic support (p <0.0001), antibiotic therapy (p = 0.0006), length of stay in the intensive care unit (p <0.0001) and length of hospital stay (p <0.0001) were greater for Group B. Conclusions: CUF with the technical modification was not better than conventional CUF, because in spite of elevating the hematocrit after CBP, it caused greater postoperative bleeding with a greater need of blood transfusions and longer hospital stays.

Artificial Neural Networks Prognostic Evaluation of Post-Surgery Complications in Patients Underwent to Coronary Artery Bypass Graft Surgery

In this paper we explore the applications of artificial neural networks in the field of heart surgery, more specifically in the prognostic evaluation of post-surgery complications, such as death, reintubation, prolonged mechanical ventilation and the need for extracorporeal circulation in patients who underwent coronary artery bypass graft surgery. Predictive variables were limited to information available before the procedure, and outcome variables were represented only by events that occurred postoperatively. We also employed the principal component analysis technique to further reduce the complexity of our input data set in an attempt to improve artificial neural network efficiency and reliability

Prevalencia de Chlamydia Pneumoniae y Mycoplasma Pneumoniae en diferentes formas de la enfermedad coronaria

Irineu Luiz Maia1,2, José Carlos Nicolau3, Maurício de Nassau Machado1,2, Lília Nigro Maia1,2, Isabela Thomaz Takakura2, Paulo Ricardo de Fernando Rocha2, José Antônio Cordeiro1, José Antônio Franchini Ramires3 Faculdade de Medicina de São José do Rio Preto (Famerp)1, Hospital de Base de São José do Rio Preto2, Instituto do Coração Faculdade de Medicina da Universidade de São Paulo (InCor USP)3, São José do Rio Preto, SP; São Paulo, SP BrasilBACKGROUND Several infectious agents have been investigated since the association between atherosclerosis and infection was demonstrated; however, the results of these studies are contradictory. OBJECTIVE To test the association between serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in different forms of acute coronary syndromes (ACS). METHODS One hundred and twenty-six patients were divided in 4 groups: ACS with ST-segment elevation (32 patients), ACS without ST-segment elevation (30 patients), chronic coronary artery disease (30 patients) and blood donors without known coronary disease (34 patients--control group). In the two first groups, serum samples were collected at hospital admission (first 24 hours of hospitalization) and after a 6-month follow-up. In the other two groups, only a basal sample was collected. Anti-Chlamydia and anti-Mycoplasma antibodies were measured by indirect immunofluorescence in all samples. RESULTS Significant differences were observed between the basal sample and the one measured after a 6-month follow-up in patients with myocardial infarction with ST-segment elevation for Chlamydia (650+/-115.7 versus 307+/-47.5, p=0.0001) as well as Mycoplasma (36.5+/-5.0 versus 21.5+/-3.5, p=0.0004). The groups with ACS had higher anti-Chlamydia and anti-Mycoplasma serum antibody levels in the basal measurement, when compared to the patients with chronic coronary disease and the control group, but the differences were not statistically significant. CONCLUSION The present study showed an association between the serum titers of anti-Chlamydia and anti-Mycoplasma antibodies in the acute phase of patients with unstable angina or myocardial infarction.