Alexandre Varela

Increased Calcification and Protein Nitration in Arteries of Chronic Kidney Disease Patients

Background: Cardiovascular disease in chronic kidney disease (CKD) has peculiar characteristics. The aim of this study was to analyze atherosclerosis, vascular calcification and nitration in arteries from CKD patients. Methods: External iliac and renal artery segments from 27 stage 5 CKD patients and 25 donor controls, respectively, were collected during the transplantation procedure. Results: CKD patients presented a significantly higher degree of lesion. In a large proportion (72%) of CKD patients, we observed vascular calcifications. Immunohistochemistry for nitrotyrosine revealed a significant increase in nitrotyrosine production in arteries from CKD patients compared with control donors. In addition, within CKD patients, nitrotyrosine staining was significantly stronger in arteries with media calcification when compared with arteries without media calcification. Conclusion: The arteriopathy in the CKD patients appears in an early age and seems to be distinct from the arteriopathy of the general population, especially due to intense calcification and vascular oxidative stress.

Avaliação e manejo da doença cardiovascular em pacientes com doença renal crônica

Cardiovascular disease is the leading cause of death in the set of chronic kidney disease (CKD) patients, whether on renal replacement therapy or conservative treatment. A better understanding of cardiovascular risk factors, diagnostic approach and management are central keys to develop strategies to reduce cardiovascular mortality among those patients. This review article discusses some aspects of pathophysiology, investigation methods and current treatment of cardiovascular disease in CKD patients.

Revascularização do miocárdio sem circulação extracorpórea em pacientes submetidos à hemodiálise

OBJECTIVE To analyze the hospital outcomes of patients, with chronic renal insufficiency in the hemodialysis, submitted to OPCAB. METHOD Fifty-one patients with chronic renal insufficiency were submitted to OPCAB. Hemodialysis was performed on the day before and the day after the operation. Myocardial revascularization was performed using LIMAs suture and suction stabilization. RESULTS Fifty-one patients, with an average of 61.28+/-11.09 years, were analyzed. Thirty patients (58.8%) were female. The predominant functional class was IV in 21 (41.1%) of the patients. The left ventricle ejection fraction was dire in 21 (41.1%) patients. The mean EUROSCORE of this series was 7.65+/-3.83 and the mean number of distal anastomosis was 3.1+/-0.78 per patient. The average time of mechanical ventilation was 3.78+/-4.35 hours and the mean ICU stay was 41.9+/-13.8 hours, while the average hospitalization was 6.5+/-1.31 days. In respect to complications, nine (17.6%) of the patients developed atrial fibrilation, and one (1.9%) patient presented with a case of ischemic stroke but had a good recovery during hospitalization. There were no deaths in this series. CONCLUSION Chronic renal patients submitted to hemodialysis were always a high risk population for myocardial revascularization. In this series, the absence of extracorporeal circulation appeared to be safe and efficient in this special subgroup of patients. The operations were performed with low indices of complications, absence of deaths and relatively low stays in the ICU and in hospital.

Revascularização total do miocárdio sem circulação extracorpórea: cinco anos de experiência

OBJECTIVE: To evaluate the immediate postoperative results of off-pump myocardium revascularization surgery by analyzing complications and mortality. METHOD: A total of 1440 patients were submitted to off-pump myocardium revascularization. The surgical technique is consisted in proximal occlusion of the approached artery, the application of the LIMA graft in the posterior pericardial deflection and stabilization of the target artery with a suction stabilizer. The distal anastomoses were performed first. RESULTS: Among the patients evaluated, 924 were male and 516 were female,with a mean age of 63.12 ± 8.76 years. The ejection fraction was normal in 749 patients, 740 (51.4%) patients had suffered previous myocardial infarction and 687 (47.6%) patients were in functional class III or IV. The mean EuroSCORE was 4.93 ± 3.32. The mean number of dial anastomoses was 3.12 ± 1.23 per patient. A total of 1173 (81.5%) patients remained less than 12 hours on mechanical ventilation and among them, 888 (61.7%) remained for less than six hours. The stay in the ICU was of one night for 330 (22.8%) patients, for two nights for 930 (64.6%) patients and 182 (12.4%) patients remained three or more nights. In regards to complications, three (0.2%) patients presented with renal insufficiency, six (0.4%) patients suffered stroke, 19 (1.3%) patients were reoperated for bleeding, 19 (1.3%) patients had mediastinitis, 18 (1.25%) patients suffered severe myocardial infarction and 212 (14.7%) presented atrial fibrillation. There were 50 (3.5%) deaths, 29 (2.5%) of them being among the 1148 operated electively, nine (4.7%) among 190 patients submitted to coronary re-operation and 12 (11.7%) among 102 patients undergoing emergency operations. CONCLUSION: With the evolution of biomedical technological, all the vessels of the heart are now approached. These data suggest that the operation for myocardial revascularization is safe and efficient. It can be applied to all patients who need coronary surgery, with low rates of complication and mortality.

Myocardial Revascularization without Extracorporeal Circulation in Patients Over 75 Years of Age. Analysis of Immediate Results

Results Arterial hypertension was present in 174 (90%), dyslipidemia in 115 (59%), smoking in 89 (46%), and diabetes in 57 (29%). Ninety-six (49.7%) patients had had a previous myocardial infarction, 53 of whom (27.4%) had experienced an acute ischemic event in a period < 30 days after surgery. Critical obstructive lesions in 3 or more coronary vessels were present in 156 (80.95%) patients, while 30 (15%) patients had an important obstruction of the left main coronary artery, and 30 (15%) patients had an ejection fraction < 30%. The score obtained according to the EUROSCORE ranged from 3 to 18, with an expected mortality rate for the group of 7.54±2.69%. The total number of distal anastomoses was 639. Seven (3.62%) patients died, 3 due to bronchopneumonia, 1 due to mediastinitis, 1 due to metabolic causes, 1 due to cardiogenic shock, and another died suddenly after refixation of a sternal dehiscence. Reoperation due to bleeding, orotracheal reintubation, and prolonged mechanical ventilation were factors associated with an increase in mortality.

Tratamento cirúrgico sem circulação extracorpórea de arteriopatia relacionada com arterite de Takayasu envolvendo aorta e vasos da base

We report the cases of 2 female patients with Takayasus arteritis referred to our service with lesions affecting the descending thoracic aorta and great vessels. One of the patients had a critical obstructive lesion in the left coronary ostium. Both patients underwent surgery without extracorporeal circulation, with full heparinization and autotransfusion.

Uso do ultrassom intracoronariano para a caracterização da doença arterial coronariana em pacientes com doença renal crônica

INTRODUCTION Chronic kidney disease patients present a very high cardiovascular mortality. Nevertheless, a comparative description of lesion characteristics, using intravascular ultrasound in dialysis patients, has not yet been reported. The objective of the present study was to analyze the plaque morphology through intravascular ultrasound in comparison to their counterparts with normal renal function. METHODS Patients were screened for coronary artery disease, and the coronary angiography was performed when indicated. Plaque morphology was evaluated by ultrasound, and findings were compared to a group of patients with coronary artery disease, who presented normal renal function, it carefully matched for all Framingham risk factors and lesion location at the coronary artery tree. RESULTS One hundred and thirty-nine patients from a single center of hemodialysis were screened for the study. Patients with coronary lesions confirmed at the angiography presented lower hemoglobin (10.8 ± 1.5 versus 12.0 ± 19; p < 0.046) levels and higher levels of low-density lipoprotein (110.6 ± 25.8 versus 75.5 ± 43.1; p < 0.004), when compared to the ones without coronary artery disease. The ultrasound revealed greater proximal reference diameter (4.1 ± 0.6 versus 3.7 ± 0.5; p < 0.007), smaller crossed sectional area (4.2±1.6 versus 5.2 ± 1.8; p < 0.02), and the calcification was located in a deeper arterial layer (69 versus 9%; p < 0.004) in patients with chronic kidney disease when compared to the Control Group. CONCLUSION Lesions of the patients with chronic kidney disease presented a larger proximal diameter and intense calcification in the deeper layer of the vessel, which suggest a greater positive remodeling effect in response to a more aggressive atherosclerotic process in the medial section of the artery.

Analysis of the immediate outcomes of a comparative randomized study between aorto-saphenous mechanical anastomosis versus conventional anastomosis

OBJECTIVE To evaluate the immediate results of mechanical aorto-saphenous anastomosis compared with conventional anastomosis. METHOD We evaluated 12 patients. The mean age ranged from 62.33 +/- 7.30 years. Of 12 patients submitted to surgery without extracorporeal circulation, 10 (83.3%) patients were male. Thirty-three proximal anastomoses were evaluated, 21 of them being performed through the conventional manner and 12 with the St. Jude Symmetry aortic connector. The time spent on anastomosis, and free flow and patency on the 4th day postoperative were analysed. RESULTS The mechanical anastomosis was successfully performed in all patients. Electrocardiographic alteration compatible with myocardial infarctation (MI) on the 2nd day postoperative was observed only in one patient. The patient was referred to angiographic restudy, becoming evident a conventional proximal anastomosis occlusion for the marginal branch. Three patients had atrial fibrillation. The average time spent to perform the mechanical anastomosis was 44.08 +/- 9.26 seconds against 3.86 +/- 0.61 minutes of the conventional anastomosis (p = 0.0022). The average blood free flow observed in the mechanical anastomosis was 302.75 +/- 82.76 mL/min versus 190.75 +/- 51.53 mL/min (p = 0.0022). In the angiographic restudy performed on the 4th postoperative day, it was detected the occlusin of three mechanical anastomosis. There was no new conventional anastomosis (p = 0.2500). CONCLUSION The present study showed a statistically significant superiority for mechanical anastomosis of the saphenous vein with the aorta when evaluated the blood free flow and the time to perform the anastomosis. In relation to the artery condition in the postoperative angiography, one cannot say there was statistically significant difference between the procedures studied.

Pode a correção cirúrgica de cardiopatias pediátricas e congênitas conviver com baixa mortalidade?: revisão de 10 anos de experiência com 1088 cirurgias

Em um periodo de 10 anos, de novembro de 1976 a novembro de 1986, foram realizadas 1088 cirurgias, em pacientes com cardiopatias pediatricas, com menos de 15 anos de idade, e em pacientes com cardiopatias congenitas. Foram corrigidos, com o auxilio da CEC, 670 casos e, com cirurgia classica, 418 casos. Foram reoperados 111 pacientes (10,2%). Pacientes com lesoes valvares adquiridas e com menos de 15 anos de Idade, analisados neste trabalho, compreenderam 120 casos (11,1%). A mortalidade hospitalar global foi de 10,4%, sendo 11,2% com auxilio de CEC e 9,1% sem CEC. Foi observada uma queda de mortalidade, nos anos de 1985 e 1986, correspondendo a 6,8% e 5,7%, respectivamente. Nesse periodo de 2 anos, foram realizadas 179 cirurgias, sendo corrigidas 54 cardiopatias congenitas cianoticas, com 7 obitos (12,9%), e 125 acianoticas, com 2 obitos (1,6%). A maior mortalidade ocorreu no primeiro ano de vida (20,7%), havendo uma diminuicao do numero de obitos nas outras faixas etarias, especialmente acima do quarto ano de vida. A analise dos fatores que influiram na diminuicao da mortalidade revelou: indicacao mais frequente de cirurgias pediatricas no primeiro ano de vida, analise cuidadosa da anatomia cirurgica, definicoes precisas do momento da intervencao e tecnicas de cirurgia, melhor protecao miocardica, condicoes fisicas e medicas no pos-operatorio e maior experiencia cirurgica.