João Nelson Rodrigues Branco

Coronary artery bypass grafting without cardiopulmonary bypass

BACKGROUND Coronary artery bypass grafting without cardiopulmonary bypass is now an accepted technique of myocardial revascularization. We herein report our total experience with this procedure. METHODS In a consecutive series of 8,751 patients operated on in our institution for coronary artery disease from 1981 to 1994, 1,274 patients received coronary artery bypass grafting without cardiopulmonary bypass. RESULTS Results indicate that the operation can be performed with an acceptable mortality (2.5%), and that all types of arterial conduits can be used. Most commonly the left anterior descending and right coronary arteries were bypassed. The incidence of arrhythmias and of pulmonary and neurologic complications were significantly lower in this group of patients compared with patients receiving coronary artery bypass grafting with cardiopulmonary bypass. Most importantly, there was decreased cost when the procedure was used because no extracorporeal circulation, cardioplegia sets, or other cannulas were used. CONCLUSIONS We conclude that the continuing use of coronary artery bypass grafting without cardiopulmonary bypass is justified and that, with proper selection of patients, the procedure is safe and cost-effective.

Off-pump versus on-pump myocardial revascularization in low-risk patients with one or two vessel disease: perioperative results in a multicenter randomized controlled trial

BACKGROUND To evaluate hospital mortality and morbidity after myocardial revascularization in a prospective and multicenter study, comparing on-pump versus off-pump in a special subset of patients with lesions in the left descending artery, alone or associated with the right coronary artery. METHODS A multicenter prospective randomized study was performed. One hundred and sixty selected low-risk patients were enrolled; 80 patients were operated on-pump (coronary artery bypass grafting [CABG], group I) and 80 patients were operated off-pump (off-pump coronary artery bypass [OPCAB], group II). One hundred and five were male and ages ranged from 39 to 70 years old; mean 58.81 +/- 9.31 and median 59. Preoperative clinical characteristics were similar in both groups; only previous myocardial infarction was higher in the OPCAB group. Patients with severe left ventricular dysfunction (FE </= 35%), renal failure and lesions of the circumflex artery and its branches were excluded, as well as patients with significant comorbidities that were inappropriate for randomization because we selected them for OPCAB procedures. RESULTS Hospital mortality was 2.5%, three patients (3.7%) in group I (on-pump) and one patient (1.2%) in group II (off-pump) (ns). The number of grafts per patients in group I was 1.81 +/- 0.6, and 1.77 +/- 0.68 in group II (p = 0.833). There was no difference in the total operation time 205.10 +/- 54.30 minutes in group I and 189.50 +/- 55.44 in group II (ns). Six patients (7.5%) had myocardial infarction in group I and three (3.7%) in group II (ns). Bleeding in the postoperative period was 680.50 +/- 434.1 mL in the on-pump group and 678.6 +/- 357.0 mL in the off-pump group (ns). Three patients (3.7%) presented transient neurologic dysfunction in group I and six patients (7.5%) in group II (ns). Intensive care stay was 2.4 +/- 1.0 days in the CABG and 2.3 +/- 0.98 days in the OPCAB group (ns). CONCLUSIONS We did not find any statistical difference in hospital mortality and morbidity using on-pump or off-pump techniques for low-risk patients.

Myocardial revascularization without extracorporeal circulation. Seven-year experience in 593 cases.

The authors present the results of 593 consecutive and non-selected patients who underwent direct myocardial revascularization without extracorporeal circulation in the period September 1981 to December 1988. The results are compared with 3086 patients who underwent conventional bypass surgery over the same period of time. The ages varied from 33 to 80 years (mean = 56) with 40 patients older than 70. The overall mortality in the group without cardiopulmonary bypass (CPB) was 1.7% (10/593) compared with 3.8% for conventional revascularization. Our mortality in the last 3 years has been 0.5% and 0% in the last 203 patients revascularized without CPB. The number of grafts varied from 1 to 5 (average 1.6). The treated arteries were: anterior descending (557), right (282) marginal (5) and circumflex marginal (4). Immediate postoperative complications were fewer and hospital discharge was earlier in the group treated without CPB. The authors conclude that this tactical alternative has the advantages of: lower morbidity and mortality, lower cost and no need for blood transfusion. Drawbacks are the need for greater technical expertise and it seems to be possible in about 19% of all patients who undergo myocardial revascularization.

Transplante cardíaco e infecção

Objective: To evaluate the incidence of infection, the etiological agents, to present the clinical aspects and the surgical morbi-mortality in patients who underwent cardiac transplant at Federal University of Sao Paulo. Material and Methods: From November 1966 to June 1998, a total of 97 patients were operated by the UNIFESP Cardiovascular Surgery team and survived longer than 1 week after the transplantation and were studied retrospectively as far as infections. The age of the patients ranged from 3 to 63 years (average 44.4 ± 13 years). Most of the patients had dilated myocardiopathy (46), or Chagas (24) or ischemis (23). The follow up ranged from 0.33 to 119 months (36 ± 30.7 months) Results: Of the 97 patients, 16 (16.4%) had infection as the main cause of death, followed by rejection in 10 (10.3%). The causes of infection were: bacterial sepsis in 6 patients, pneumonia in 6, intra-abdominal infection in 2, toxoplasmosis in 1 and cytomegalovirus infection in 1. There were 142 infection episodes, bacterial 76 (52.5%), viral 34 (28.8%), fungi 20 (17.5%) and protozoa 12 (12.4%). There were 8 episodes of the reactivation were treated successfully with alopurinol. Conclusions: Our data showed the predominance of bacterial infections as the cause of most mortality. In transplanted patients suffering from Chagas´disease, the reactivation of the disease may be adequately controlled by means of alopurinol. Such data serve as orientation in our community for our programs of transplants, since they show particular aspects of our enviroment.

Cytokines and pediatric open heart surgery with cardiopulmonary bypass

It is well known that, subsequent to cardiopulmonary bypass, and particularly in children, an inflammatory response within the body can often result in a characteristic syndrome. Recently, it has been suggested that this phenomenon is due to a systemic inflammatory response, with significant involvement of cytokines. With this in mind, we investigated the behavior of tumour necrosis factor-alpha and interleukin-6 during the operative and in the immediate postoperative period in a group of children submitted to open heart surgery. We investigated any possible relation between the levels of these cytokines in the serum and the length of cardiopulmonary bypass, with the serum levels of lactate, and with the extent of use of inotropic drugs in postoperative period. The cytokines were measured in samples withdrawn after induction of anesthesia, after 10 minutes of cardiopulmonary bypass, after re-establishment of circulation, and then 2 and 24 hours after the end of cardiopulmonary bypass. The levels of tumour necrosis factor-alpha and interleukin-6 increased between the beginning and at two hours of the end of cardiopulmonary bypass. There was no correlation between the levels of these cytokines in the serum and the length of cardiopulmonary bypass, although there was a positive relation between levels of interleukin-6 and lactate in samples withdrawn at two hours of the end of bypass, and the measured levels of the cytokines correlated with the extent of inotropic drugs employed in the postoperative period.

Estimulação elétrica nervosa transcutânea de curta duração no pós-operatório de cirurgia cardíaca

BACKGROUND: Respiratory muscle strength has been related to the postoperative outcome of cardiac surgeries. The main documented therapeutic purpose of transcutaneous electrical nerve stimulation (TENS) is the reduction of pain, which could bring secondary benefits to the respiratory muscles and, consequently, to lung capacities and volumes. OBJECTIVES: The objective of the present study was to evaluate the effectiveness of short-duration transcutaneous electrical nerve stimulation (TENS) in the reduction of pain and its possible influence on respiratory muscle strength and lung capacity and volumes of patients in the postoperative period of cardiac surgery. METHODS: Twenty five patients with mean age of 59.9 ± 10.3 years, of whom 72% were men, and homogeneous as regards weight and height, were randomly assigned to two groups. One group received therapeutic TENS (n = 13) and the other, placebo TENS (n = 12), for four hours on the third postoperative day of cardiac surgery. Pain was analyzed by means of a visual analogue scale, and of respiratory muscle strength as measured by maximum respiratory pressures and lung capacity and volumes before and after application of TENS. RESULTS: Short-duration TENS significantly reduced pain of patients in the postoperative period (p < 0.001). Respiratory muscle strength (p < 0.001), tidal volume (p < 0.001) and vital capacity (p < 0.05) significantly improved after therapeutic TENS, unlike in the placebo group. CONCLUSION: Short-duration TENS proved effective for the reduction of pain and improvement of respiratory muscle strength, as well as of lung volumes and capacity. (Arq Bras Cardiol 2010; 94(3):325-331)

Uso de corticóide como inibidor da resposta inflamatória sistêmica induzida pela circulação extracorpórea

Cardiopulmonary bypass (CPB) induces the development of a systemic inflammatory response syndrome, with the release of cytokines that are responsible for many clinical manifestations. PURPOSE: The purpose of the study was to observe the release of the cytokines - tumor necrosis factor alpha (TNFa) and Interleukine-6 (IL-6), and to verify the clinical alterations produced in patients undergoing myocardial revascularization with CPB, with or without corticoids. MATERIAL AND METHODS: Thirty patients were studied - 15 used corticoid (methylprednisolone, 30 mg/kg -Group I) and 15 did not (Group II). Serial blood samples were collected and the TNFa and IL-6 release were analyzed, as well as the leukocyte count, erythrocyte sedimentation rate and glycemia. The blood pressure, cardiac rate, temperature, postoperative bleeding, orotracheal tubing time and inotropic drug requirement were also compared. Statistical significance was assumed when p £ 0.05. RESULTS: In Group I TNFa was not detected and IL-6 was detected in 13 patients, with levels ranging from 8.6 to 101.8 pg/ml. In Group II TNFa was detected in 13 patients, with levels between 5.4 and 231.0 pg/ml. The IL-6 in this group was detected in 15 patients, with higher levels than those in Group I, varying between 5.5 and 2569.0 pg/ml. The Group I patients had higher medium blood pressure (7.9 ± 0.5 vs 7.3 ± 0.4 mmHg) and lower inotropic drug requirement (5 vs 11). They evolved with less tachycardia (105.6 ± 5.9 vs 109.3 ± 7.2 bpm), lower temperature (36.5 ± 0.2 vs 37.3 ± 0.2°C), lower postoperative bleeding, (576.6 ± 119.5 vs 810.0 ± 176.2 ml), shorter orotracheal tubing time (11.0 ± 2.0 vs 14.6 ± 2.9 hs) and lower leukocytosis. The glycemia level was just significant (Group I > Grupo II) in the immediate postoperative and in the first postoperative samples. The erythrocyte sedimentation rate did not present significant statistical difference between the two groups. CONCLUSION: The methylprednisolone significantly inhibited the release of inflammatory cytokines mainly the TNFa. The systemic adverse effects caused by the inflammatory response after CPB were minimized by corticoid use.

Is the number of microembolic signals related to neurologic outcome in coronary bypass surgery

Coronary artery bypass surgery (CABG) without cardiopulmonary bypass (CPB) may potentially reduce the number of microembolic signals (MES) associated with aortic manipulation or generated by the pump circuit, resulting in a better neurologic outcome after surgery. Our aim was to compare the frequency of MES and neurologic complications in CABG with and without CPB. Twenty patients eligible to routine CABG without CPB were randomized to surgery with CPB and without CPB and continuously monitored by transcranial Doppler. Neurologic examination was performed in all patients before and after surgery. The two groups were similar with respect to demographics, risk factors, grade of aortic atheromatous disease and number of grafts. The frequency of MES in the nonCPB group was considerably lower than in CPB patients, however, we did not observe any change in the neurologic examination during the early postoperative period. Neurologic complications after CABG may be related to the size and composition of MES rather than to their absolute numbers. A large prospective multicentric randomized trial may help to elucidate this complex issue.

A new surgical approach for treating dilated cardiomyopathy with mitral regurgitation

OBJECTIVE To evaluate the early outcome of mitral valve prostheses implantation and left ventricular remodeling in 23 patients with end-stage cardiomyopathy and secondary mitral regurgitation (NYHA class III and IV). METHODS Mitral valvular prosthesis implantation with preservation of papillary muscles and chordae tendinae, and plasty of anteriun cuspid for remodeling of the left ventricle. RESULTS The surgery was performed in 23 patients, preoperative ejection fraction (echocardiography) varied from 13% to 44% (median: 30%). In 13 patients associated procedures were performed: myocardial revascularization (9), left ventricle plicature repair (3) and aortic prosthesis implantation (1). Early deaths (2) occurred on the 4th PO day (cardiogenic shock) and on the 20th PO day (upper gastrointestinal bleeding), and a late death in the second month PO (ventricular arrhythmia). Improvement occurred in NYHA class in 82. 6% of the patients (P<0.0001), with a survival rate of 86.9% (mean of 8.9 months of follow-up). CONCLUSION This technique offers a promising therapeutic alternative for the treatment of patients in refractory heart failure with cardiomyopathy and secondary mitral regurgitation.

Avaliação da segurança do teste de caminhada dos 6 minutos em pacientes no pré-transplante cardíaco

FUNDAMENTO: El test de marcha de 6 minutos (TM6m) ha sido utilizado como forma de evaluacion de la capacidad funcional, del estadiamiento clinico y el pronostico cardiovascular. La seguridad y el impacto metabolico son poco descritos en la literatura, principalmente en pacientes con insuficiencia cardiaca severa e indicacion clinica para transplante cardiovascular Objetivo: Evaluar la ocurrencia de arritmias y alteraciones cardiovasculares durante el TM6m. Correlacionar el desempeno en el TM6m con el estadiamiento clinico y el pronostico cardiovascular. METODOS: Un total de 12 pacientes, 10 varones, con edad de 52 ± 8 anos, fueron sometidos a evaluacion inicial. Realizaron el TM6m con monitoreo electrocardiografico por telemetria, senales vitales y lactato. Se siguieron a los individuos por 12 meses. RESULTADOS: Los pacientes recorrieron 399,4 ± 122,5 (D, m), alcanzando un esfuerzo percibido (EP) de 14,3 ± 1,5 y variacion del 34% en la frecuencia cardiaca basal. Dos pacientes presentaron arritmia de mayor severidad pre-TM6m y no mostraron empeoramiento ante el esfuerzo; cuatro tuvieron elevacion significativa en los niveles de lactato sanguineo (>5 mmol/dl), y tres interrumpieron el examen. La distancia recorrida evidencio correlacion con la fraccion de eyeccion (%) y la clasificacion funcional (NYHA). Tras 12 meses de seguimiento, tres pacientes murieron, y siete se reinternaron por descompensacion cardiaca. La relacion (D/EP) y frecuencia cardiaca de recuperacion en el segundo minuto (FCR2, lpm) fueron inferiores en el grupo obito. CONCLUSION: El comportamiento clinico y electrocardiografico sugiere que el metodo es seguro, pero se puede considerarlo de alta intensidad para algunos pacientes con insuficiencia cardiaca severa. Variables relacionadas al desempeno en el TM6m pueden estar asociadas con la mortalidad en el seguimiento de un ano.BACKGROUND The 6-minute walk test (6WT) has been used as a means of assessment of the functional capacity, clinical staging and cardiovascular prognosis. Its safety and metabolic impact have not been frequently described in the literature, especially in patients with severe heart failure with clinical indication for cardiovascular transplantation. OBJECTIVE To evaluate the occurrence of arrhythmias and cardiovascular changes during 6WT. To correlate 6WT performance with clinical staging and cardiovascular prognosis. METHODS Twelve patients, 10 of whom males, aged 52 +/- 8 years were evaluated at baseline. 6WT was performed with telemetry electrocardiography, vital signs and lactate monitoring. The patients were followed-up for 12 months. RESULTS The patients walked 399.4+/-122.5 (D, m), reaching a perceived exertion (PE) of 14.3+/-1.5 and a 34% baseline heart rate variation. Two patients presented more severe pre-6WT arrhythmia which did not worsen with the exercise, four patients presented a significant increase of blood lactate levels (>5 mmol/dl), and three interrupted the test. The distance walked correlated with the ejection fraction (%) and functional class (NYHA). After 12-month follow-up, three patients died and seven were rehospitalized for cardiac decompensation. The D/PE ratio and 2-minute heart rate recovery (HRR2, bpm) were lower in the death group. CONCLUSION The clinical and electrocardiographic behaviors suggest that the method is safe, but it may be considered too strenuous for some patients with severe heart failure. Variables related to 6WT performance may be associated with the one-year follow-up mortality.