João Batista Petracco

Predictors of mediastinitis after cardiac surgery

OBJECTIVE: Mediastinitis is a serious complication of open-heart surgery, with an incidence that varies from 0.4% to 5%, mortality from 10% to 47% and a high morbidity rate. OBJECTIVE: To identify preoperative and trans-operative risk factors of mediastinitis after open-heart surgery in our hospital. METHOD: This was a prospective study of 1298 patients submitted to the open-heart surgery in Sao Lucas hospital in the period from March 1997 to May 2000. Nine potential risk factors associated with mediastinitis were studied (obesity, diabetes mellitus, chronic obstructive pulmonary disease -COPD-, internal mammary artery, cardiopulmonary bypass time, smoking, gender, ejection fraction and previous heart surgery) using univariate analysis, where necessary followed by multivariate logistic regression. RESULTS: Of the 1298 studied patients, 62.6% were men and 18.3 suffered from diabetes. Thirty-eight patients (2.9%) presented with mediastinitis postoperatively, and six (15.8%) of these died. Four variables identified as risk factors by univariate analysis (p<0.05) and were after analysed by logistic regression. Three variables were identified as independent predictors of mediastinitis: obesity (p=0.008), COPD (p=0.007) and diabetes mellitus (p= 0.009), even when gender and age were analysed. The internal mammary artery graft was observed as risk predictor only when associated to the obesity. CONCLUSION: In our hospital, mediastinitis occurs most frequently in patients suffering from obesity, diabetes, and/or COPD and in the obese patients in which internal mammary artery was used.OBJECTIVE: Mediastinitis is a serious complication of open-heart surgery, with an incidence that varies from 0.4% to 5%, mortality from 10% to 47% and a high morbidity rate. OBJECTIVE: To identify preoperative and trans-operative risk factors of mediastinitis after open-heart surgery in our hospital. METHOD: This was a prospective study of 1298 patients submitted to the open-heart surgery in Sao Lucas hospital in the period from March 1997 to May 2000. Nine potential risk factors associated with mediastinitis were studied (obesity, diabetes mellitus, chronic obstructive pulmonary disease -COPD-, internal mammary artery, cardiopulmonary bypass time, smoking, gender, ejection fraction and previous heart surgery) using univariate analysis, where necessary followed by multivariate logistic regression. RESULTS: Of the 1298 studied patients, 62.6% were men and 18.3 suffered from diabetes. Thirty-eight patients (2.9%) presented with mediastinitis postoperatively, and six (15.8%) of these died. Four variables identified as risk factors by univariate analysis (p<0.05) and were after analysed by logistic regression. Three variables were identified as independent predictors of mediastinitis: obesity (p=0.008), COPD (p=0.007) and diabetes mellitus (p= 0.009), even when gender and age were analysed. The internal mammary artery graft was observed as risk predictor only when associated to the obesity. CONCLUSION: In our hospital, mediastinitis occurs most frequently in patients suffering from obesity, diabetes, and/or COPD and in the obese patients in which internal mammary artery was used.

Naproxen as Prophylaxis against Atrial Fibrillation after Cardiac Surgery: The NAFARM Randomized Trial

PURPOSE We sought to assess the effect of naproxen versus placebo on prevention of atrial fibrillation after coronary artery bypass graft (CABG) surgery. METHODS In this randomized, double-blind, placebo-controlled, single-center trial of 161 consecutive patients undergoing CABG surgery, patients received naproxen 275 mg every 12 hours or placebo at the same dosage and interval over 120 hours immediately after CABG surgery. The primary outcome was the occurrence of atrial fibrillation in the first 5 postoperative days. RESULTS The incidence of postoperative atrial fibrillation was 15.2% (12/79) in the placebo versus 7.3% (6/82) in the naproxen group (P=.11). The duration of atrial fibrillation episodes was significantly lower in the naproxen (0.35 hours) versus placebo group (3.74 hours; P=.04). There was no difference in the overall days of hospitalization between placebo (17.23±7.39) and naproxen (18.33±9.59) groups (P=.44). Intensive care unit length of stay was 4.0±4.57 days in the placebo and 3.23±1.25 days in the naproxen group (P=.16). The trial was stopped by the data monitoring committee before reaching the initial target number of 200 patients because of an increase in renal failure in the naproxen group (7.3% vs 1.3%; P=.06). CONCLUSIONS Postoperative use of naproxen did not reduce the incidence of atrial fibrillation but decreased its duration, in a limited sample of patients after CABG surgery. There was a significant increase in acute renal failure in patients receiving naproxen 275 mg twice daily. Our study does not support the routine use of naproxen after CABG surgery for the prevention of atrial fibrillation.

Autoantibodies to the Atheroma Component Beta2-Glycoprotein I and Risk of Symptomatic Peripheral Artery Disease

Peripheral artery disease (PAD) is mostly related to atherosclerosis. Autoimmunity and, in particular, antibodies to cardiolipin (aCL) and phospholipid cofactors such as beta2-glycoprotein I (beta2-gpI) might influence the development of atheroma. Beta2-glycoprotein I (beta2-gpI) has been found in atheroma. It has previously been shown that immunoglobulin A (IgA) anti-beta2-gpI antibodies are associated with a risk of cerebral ischemia and myocardial infarction. This case control study aimed to determine whether elevated levels of aCL/anti-beta2-gpI antibodies are associated with a risk of symptomatic PAD (sPAD). Cases comprised a nonselected population of patients with sPAD (intermittent claudication or critical ischemia). Patient recruitment was based on arteriography changes. Controls were selected from patients admitted to orthopedic wards as a result of fractures or muscle-ligamentous disorders. Age, sex, race, hypertension, smoking, diabetes mellitus, and hypercholesterolemia were evaluated as risk factors in both groups. IgG/IgM/IgA aCL and anti-beta2-gpI were detected by enzyme-linked immunoabsorbant assays (ELISA). To estimate the grade of association of antibodies with sPAD, odds ratios (OR) were calculated. Logistic regression was utilized for adjustment of confounding factors. Seventy-seven cases and 93 controls were studied. The mean age was 61.5 years for cases and 47.5 years for controls (p <0.001). Among the risk factors evaluated, the presence of hypertension showed the strongest association with sPAD (OR 12.1; 95%CI 5.8—30). The presence of IgA anti-beta2-gpI was independently associated with sPAD (OR 5.4; 95%CI 1.8—15.8; p = 0.01). IgA aCL was strongly associated with the outcome (nonadjusted OR 11.5 after Agresti correction). IgA aCL and IgA anti-beta2-gpI antibodies were not associated with any known risk factors for sPAD or with arteriography changes. The occurrence of these autoantibodies might represent one of the links between autoimmunity and atherosclerosis in patients with sPAD.

The use of inhibitors of angiotensin-converting enzyme and its relation to events in the postoperative period of CABG

BACKGROUND Angiotensin-converting enzyme (ACE) inhibitors reduce the chance of death, myocardial infarction (MI) and cerebrovascular accident (CVA) in patients with coronary disease. However there is no consensus as to its indication in patients undergoing coronary artery bypass grafting (CABG). OBJECTIVE To assess the relationship between preoperative use of ACE inhibitors and clinical outcomes after CABG. METHODS Retrospective cohort study. We included data from 3,139 consecutive patients undergoing isolated CABG in Brazilian tertiary care hospital between January 1996 and December 2009. Follow-up was until discharge or death. Clinical outcomes after surgery were analyzed between users and nonusers of ACE inhibitors preoperatively. RESULTS Fifty-two percent (n=1,635) of patients received ACE inhibitors preoperatively. The use of ACE inhibitors was an independent predictor of need for inotropic support (OR 1.24, 95% CI 1.01 to 1.47, P = 0.01), acute renal failure (OR 1.23, 95% CI 1.01 to 1.73, P = 0.04) and progression to atrial fibrillation (OR 1.32, 95% CI 1.02 to 1.7, P = 0.03) postoperatively. The mortality rate among patients receiving or not preoperative ACE inhibitors was similar (10.3% vs. 9.4%, P = 0.436), as well as the incidence of myocardial infarction and stroke (15.6% vs. 15.0%, P = 0.694 and 3.4% vs. 3.5%, P = 0.963, respectively). CONCLUSION The use of preoperative ACE inhibitors was associated with increased need for inotropic support and higher incidence of acute renal failure and postoperative atrial fibrillation, not associated with increased rates of myocardial infarction, stroke or death.

Predictors of stroke in patients undergoing cardiac surgery

Objective To determine the risk factors related to the development of stroke in patients undergoing cardiac surgery. Methods A historical cohort study. We included 4626 patients aged > 18 years who underwent coronary artery bypass surgery, heart valve replacement surgery alone or heart valve surgery combined with coronary artery bypass grafting between January 1996 and December 2011. The relationship between risk predictors and stroke was assessed by logistic regression model with a significance level of 0.05. Results The incidence of stroke was 3% in the overall sample. After logistic regression, the following risk predictors for stroke were found: age 50-65 years (OR=2.11 - 95% CI 1.05-4.23 - P=0.036) and age >66 years (OR=3.22 - 95% CI 1.6-6.47 - P=0.001), urgent and emergency surgery (OR=2.03 - 95% CI 1.20-3.45 - P=0.008), aortic valve disease (OR=2.32 - 95% CI 1.18-4.56 - P=0.014), history of atrial fibrillation (OR=1.88 - 95% CI 1.05-3.34 - P=0.032), peripheral artery disease (OR=1.81 - 95% CI 1.13-2.92 - P=0.014), history of cerebrovascular disease (OR=3.42 - 95% CI 2.19-5.35 - P<0.001) and cardiopulmonary bypass time > 110 minutes (OR=1.71 - 95% CI 1.16-2.53 - P=0.007). Mortality was 31.9% in the stroke group and 8.5% in the control group (OR=5.06 - 95% CI 3.5-7.33 - P<0.001). Conclusion The study identified the following risk predictors for stroke after cardiac surgery: age, urgent and emergency surgery, aortic valve disease, history of atrial fibrillation, peripheral artery disease, history of cerebrovascular disease and cardiopulmonary bypass time > 110 minutes.

Alta dose de amiodarona em curto período reduz incidência de fibrilação atrial e flutter atrial no pós-operatório de cirurgia de revascularização miocárdica

OBJECTIVE To investigate whether oral amiodarone administered before surgery for a short period in high dose would reduce the incidence of postoperative atrial fibrillation or atrial flutter and reduces the length of hospital stay. METHODS In the double-blind, randomized study, 93 patients were given either oral amiodarone (46 patients) or placebo (47 patients). Therapy consisted of 600 mg of amiodarone three times a day, started at minimum 30 hours and at maximum 56 hours before surgery. RESULTS Postoperative atrial fibrillation or atrial flutter occurred in 8 of 46 patients in the amiodarone group (17.4%) and 19 of the 47 patients in the placebo group (40.4%) (p=0.027). The mean dose of amiodarone was 2.8 g. Patients in the amiodarone group were hospitalized for 8.9+/-3.1 days and patients in the placebo group were hospitalized for 11.4+/-8.7 days (p=0.07). The hospital length were significantly prolonged in patients who developed atrial arrhythmias after surgery, despite the treatment received.(p<0.001). CONCLUSION This new alternative way of using amiodarone in high dose and in a short-term period before surgery reduce the incidence of postoperative atrial fibrillation or atrial flutter in coronary artery bypass graft surgery.

Predictors of perioperative myocardial infarction in surgical myocardial revascularization

Objective: To evaluate which preoperative and transoperative variables are predictors for the occurrence of myocardial infarction in the perioperative period of surgical myocardial revascularization in a general hospital in Porto Alegre, Brazil. Method: A retrospective cohort study was made of the database of heart surgery in the Hospital Sao Lucas of the Pontificia Universidade Catolica in Rio Grande do Sul analyzing 1471 consecutive patients who underwent on-pump surgical myocardial revascularization from January 1998 to December 2002. Results: Fourteen percent of the patients presented with perioperative myocardial infarction. The variables that proved to be independent predictors of perioperative myocardial infarction in surgical myocardial revascularization in this study were: prior surgical myocardial revascularization (OR: 2.070 – p=0.036), left main coronary artery lesion (OR: 1.692 – p=0.006), female (OR: 1.572 – p=0.034), preoperative unstable angina (OR: 1.533 – p=0.011), high number of grafts (OR: 1.336 – p=0.001) and prolonged cardiopulmonary bypass time (OR: 1.013 – p<0.001). Conclusions: Prior surgical myocardial revascularization, left main coronary artery lesion, female, preoperative unstable angina, high number of grafts and prolonged cardiopulmonary bypass time proved to be independent predictors of perioperative myocardial infarction in surgical myocardial revascularization in this study of patients from a general hospital from Porto Alegre, Brazil.

Fibrinogênio sérico pré-operatório como preditor de infarto do miocárdio na cirurgia de revascularização miocárdica

OBJECTIVE Determine the predictive level of preoperative serum fibrinogen level for the occurrence of MI in perioperative surgical myocardial revascularization (SMR), as well as for other impacting outcomes, such as stroke, pulmonary thromboembolism (PTE), and death, separately or in combination. METHODS A retrospective cohort study based on the heart surgery database analysis from São Lucas Hospital, at Rio Grande do Sul Catholic University with 1,471 consecutive patients submitted to extracorporeal SMR between January, 1998 and December, 2002. RESULTS Perioperative MI occurred in 14% of sample patients. No association was shown between preoperative fibrinogen and perioperative MI (410.60 +/- 148.83 mg/dl for the study group x 401.57 +/- 135.23 mg/dl for control group--p = 0.381--RC = 1.000--CI95%: 0.998-1.002--p = 0.652), combined outcome for MI, stroke, PTE, and death (411.40 +/- 153.52 mg/dL for the group reporting outcome x 400.31 +/- 131.98 mg/dL for the group with no outcome--p = 0.232) and neither separately. CONCLUSION In that sample, preoperative serum fibrinogen level did not show any association with the occurrence of perioperative MI in SMR, neither with other impacting outcomes, stroke, PTE, and mortality, whether separately or as composite endpoints.

Estudo comparativo das estimulações ventricular direita e biventricular no pós-operatório de revascularização miocárdica

OBJETIVO: Nos anos recentes, a ressincronizacao ventricular tem sido proposta como adjuvante no tratamento da insuficiencia cardiaca congestiva. O objetivo deste estudo e comparar as alteracoes eletrocardiograficas e o efeito hemodinâmico imediato das estimulacoes ventricular direita (EVD) e biventricular (EBV), no pos-operatorio de operacao de revascularizacao miocardica (CRM) com circulacao extracorporea (CEC). CASUISTICA E METODOS: Em um ensaio clinico cruzado, 13 pacientes com doenca coronaria multiarterial, e fracao de ejecao inferior a 50%, foram submetidos a estimulacao epicardica temporaria univentricular direita e biventricular, no 5° dia de pos-operatorio. As variaveis analisadas foram duracao do complexo QRS, dimensoes do atrio esquerdo (AE) e ventriculo esquerdo (VE), fracao de encurtamento do VE (delta D) e fracao de ejecao do VE. Os grupos foram comparados atraves do teste de t de Student para amostras pareadas, considerando-se nivel de significância de 0,05. RESULTADOS: A duracao media do complexo QRS foi de 185±26 ms durante a EVD, e de 126±37 ms com a EBV (p<0,001). O diâmetro medio do AE com a EVD foi de 40±4 mm, e de 35±4 mm na EBV (p<0,001). As medias dos diâmetros diastolico e sistolico finais do VE foram, respectivamente, de 49±13 mm e 59±11 mm com a EVD, e de 42±12 mm e 52±10 mm durante a EBV (p<0,001). A delta D media do VE determinada pela EVD foi de 18±7%, e de 22±8% com a EBV (p=0,017). A fracao de ejecao media do VE com a EVD foi de 33±14%, e de 46±17% durante a EBV (p<0,001). CONCLUSAO: No modelo estudado, a estimulacao biventricular temporaria determinou melhora significativa do desempenho hemodinâmico, em comparacao a estimulacao ventricular direita, e um complexo QRS com duracao proxima a fisiologica.

Avaliação da Relação do Índice Tornozelo-Braquial com a Gravidade da Doença Arterial Coronária

Introducao: A Doenca Arterial Periferica (DAP) esta associada a eventos cardiovasculares podendo ser diagnosticada e estimada atraves do Indice Tornozelo-Braquial (ITB). Esta bem estabelecido que o ITB e fator agravante na estratificacao de risco cardiovascular, mas sua contribuicao para definir a gravidade do acometimento arterial coronariano nao esta bem estabelecida. Objetivo: O estudo comparou o valor do ITB com a gravidade da doenca aterosclerotica coronariana pelo Escore de Syntax (ES) em pacientes com Sindrome Coronariana Aguda (SCA). Metodos: Estudo prospectivo com a medida do ITB de todos pacientes internados com SCA no Hospital Sao Lucas da PUCRS, consecutivamente, de maio a setembro de 2016, e a comparacao de seu valor com o ES destes pacientes e as respectivas formas de apresentacao da SCA. Resultados: Estudamos 101 pacientes, com media de idade de 62,6±12,0 anos, 58 (57,4% ) masculinos, 74 (82,2% ) hipertensos, 33 (45,8%) diabeticos e 46 (45,5% ) apresentaram infarto agudo do miocardio com infradesnivel do segmento ST (IAMCSST). A gravidade da DAP nao teve relacao com a gravidade anatomica da doenca coronariana. Encontramos uma associacao significativa dos pacientes com ES intermediario com o infarto agudo do miocardio sem supradesnivel do segmento ST (IAMSSST) e de ES baixo com angina instavel (AI) OR (IC95%): 1,11 (1,03-1,20) (P=0,004), que se manteve apos analise multivariada, ajustada para idade, tabagismo, historia familiar de doenca arterial coronaria (DAC) e DAC previa OR (IC95%): 1,13 (1,02-1,25) (P=0,019). Conclusoes: A analise dos nossos resultados, demonstram que pacientes com ITB menor que 0,9 nao apresentaram associacao com maior complexidade de doenca aterosclerotica coronariana determinados pelo ES em pacientes com SCA. Os pacientes com IAMSSST estiveram mais associados com ES intermediario.