Antônio Carlos Brandi

Oxigenação extracorpórea por membrana e alterações hematológicas em estudo experimental

Extra-corporeal membrane oxygenation is a technique of prolonged cardiopulmonary support, with the objective of assisting the lungs and/or heart when they start to fail and do not respond to conventional non-invasive treatment. The aim of this study was to evaluate hematological alterations during 12 hours of extra-corporeal membrane oxygenation in animals. Eleven sheep, six males and five females, of the Santa Ines breed with weights ranging from 5.4 to 15kg (12.2±3.1kg) were studied. With the first five animals, Ringer solution with sodium lactate (Ringer - Lactato Glicolabor - Ribeirao Preto - SP) and a 3.5% gelatine solution (Hisocel - Campinas -SP) were used to prime the extra-corporeal circuit in the proportion of 2:1 making a total of 750ml. In the sixth animal the volume of the circuit primer was reduced to 450ml, composed of 250ml of Ringer solution with sodium lactate and 200ml of 3.5% gelatine solution. In the other 5 animals 250ml of total fresh blood anticoagulated with sodium citrate and 200ml of Ringer solution with sodium lactate were employed. The blood tests performed were: hematocrit, haemoglobin, leukocytes, platelets, albumin and globulin. Mann-Whitney and variation analysis tests were used for statistical evaluation and, in the case that the variation analysis gave a significant difference (p < 0.05), the Tukey test was applied. A reduction of all the elements analysed was observed with a significant statistical difference in the values of hematocrit and leukocytes between the two groups. The hematological alterations seen in this study were exclusively due to the excessive supply of fluid volumes.

Revascularização do miocárdio com cirurgia minimamente invasiva (MIDCAB): resultados em 46 pacientes

Objective: To present the experience with myocardial revascularization by Minimally Invasive Direct Coronary Artery Bypass Graft via left anterior minithoracotomy without extracorporeal circulation (MIDCAB). Material and Methods: 46 patients were submitted to MIDCAB from February 1997 to January 1998. Everyone has obstructive disease in the proximal portion of the interventricular descending artery (IDA). The technique consisted of a small transverse incision, of about 8.0 cm, traverse, in the left infra-mammary area, allowing good visibility and easy access for dissection of the thoracic internal artery (TIA) and anastomosis with IDA. The evaluation of the results was made by clinical, laboratory and angiographic control. Results: The mean duration of operation was 2 hours with about 18 hours of permanence in ICU and 5 days of maximum hospital stay. There were no intra-operative deaths. There was a case of sudden death after discharge (15o post-operative day). The patients followed did not refer anginal pain. Four cases of TIA occlusion and 2 AIA stenoses were documented, probably secondary to vessel banding during the procedure. There was no correlation between troponin-I blood levels and occlusion of the graft. It was verified that the levels of troponin-I in patients submitted to MIDCAB were significantly lower than in the conventional procedure. There was no significant clinical complication. Conclusions: MIDCAB has proved to be a useful procedure with low morbidity and mortality, with the possibility of shorter hospital stay and consequent lower cost. The low Troponin-I blood levels indicate reduced myocardial injury during the procedure.

Modes of induced cardiac arrest: hyperkalemia and hypocalcemia--literature review.

The entry of sodium and calcium play a key effect on myocyte subjected to cardiac arrest by hyperkalemia. They cause cell swelling, acidosis, consumption of adenosine triphosphate and trigger programmed cell death. Cardiac arrest caused by hypocalcemia maintains intracellular adenosine triphosphate levels, improves diastolic performance and reduces oxygen consumption, which can be translated into better protection to myocyte injury induced by cardiac arrest.

The importance of troponin I in the diagnosis of myocardial infarction in the postoperative of coronary artery bypass graft surgery

OBJECTIVE The aim of this study is to establish a cut-off value for troponin I by correlating it to occurrence of postoperative myocardial infarction. METHODS 180 consecutive patients with coronary disease referred for surgery were included. The mean age of the patients were 60.6 (+/-9.3) years, with 119 (66.1%) males and 61 (33.9%) females. The patients were divided into two groups: group without myocardial infarction (A)--170 patients--and with myocardial infarction (B)--10 patients.The troponin I was collected from each patient at the beginning of anesthesia and on the second postoperative day by correlating it to presence or not of postoperative myocardial infarction. StatsDirect 1.6.0 for Windows was used for statistical analysis. RESULTS Preoperative troponin I was 1.0 (+/-6) ng/ml as mean. Univariate logistic regression showed correlation of troponin I of the second postoperative day with myocardial infarction (P=0.0005). ROC curve was used to define the cutoff value, and 6.1 ng/ml (sensitivity=90.0%, specificity=82.1%, OR=49.8 with CI=95% 6.1- 410.4, P<0.0001) were found. CONCLUSION The chance of a patient with postoperative myocardial infarction to present troponin I equal to or higher than 6.1 ng/ml is 49.8-fold higher than the chance of a patient without infarction to present troponin I higher than this value.

Risk factors for mortality of patients undergoing coronary artery bypass graft surgery

Introduction Coronary artery bypass grafting is a safe procedure performed worldwide with low rates of mortality and morbidity in general population. Objective To investigate risk factors for mortality of patients undergoing coronary artery bypass grafting coronary artery bypass grafting surgery. Methods A total of 1,628 consecutive patients undergoing on-pump coronary artery bypass grafting were retrospectively studied from December 1999 to February 2012. Data analysis involved paired Student t test, Mann-Whitney test and Fisher’s exact test for the categorical data. Logistic regression, Odds Ratio and 95%CI were used for definition of risk factors for mortality. Results Of a total of 1,628 patients undergoing on-pump coronary artery bypass grafting, 141 (8.7%) died. The following risk factors for mortality were identified after logistic regression: dialysis (OR=7.61; 95%CI 3.58-16.20), neurologic dysfunction type I (OR=4.42; 95%CI 2.48-7.81), use of IABP (OR=3.38; 95%CI 1.98-5.79), cardiopulmonary bypass time (OR=3.09; 95%CI 2.04-4.68), serum creatinine on admission and peak values > 0.4mg/dL (OR=2.67; 95%CI 1.79-4.00), age > 65 years (OR=2.31; 95%CI 1.55-3.44), and time between hospital admission and and surgical procedure (OR=1.53; 95%CI 1.03-2.27). Conclusion Dialysis, type I neurologic dysfunction, use of IABP, cardiopulmonary bypass time (> 115 minutes), serum creatinine on admission and peak values>0.4mg/dL, age > 65 years and time between hospital admission and surgical procedure were considered as risk factors for mortality in patients undergoing on-pump coronary artery bypass grafting surgery.

The calcium paradox - What should we have to fear?

The calcium paradox was first mentioned in 1966 by Zimmerman et al. Thereafter gained great interest from the scientific community due to the fact of the absence of calcium ions in heart muscle cells produce damage similar to ischemia-reperfusion. Although not all known mechanisms involved in cellular injury in the calcium paradox intercellular connection maintained only by nexus seems to have a key role in cellular fragmentation. The addition of small concentrations of calcium, calcium channel blockers, and hyponatraemia hypothermia are important to prevent any cellular damage during reperfusion solutions with physiological concentration of calcium.

Comparison of fractal dimension and Shannon entropy in myocytes from rats treated with histidine-tryptophan-glutamate and histidine-tryptophan cetoglutarate

Introduction Solutions that cause elective cardiac arrest are constantly evolving, but the ideal compound has not yet been found. The authors compare a new cardioplegic solution with histidine-tryptophan-glutamate (Group 2) and other one with histidine-tryptophan-cetoglutarate (Group 1) in a model of isolated rat heart. Objective To quantify the fractal dimension and Shannon entropy in rat myocytes subjected to cardioplegia solution using histidine-tryptophan with glutamate in an experimental model, considering the caspase markers, IL-8 and KI-67. Methods Twenty male Wistar rats were anesthetized and heparinized. The chest was opened, the heart was withdrawn and 40 ml/kg of cardioplegia (with histidine-tryptophan-cetoglutarate or histidine-tryptophan-glutamate solution) was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter placed in the Langendorff apparatus for 30 min with Ringer-Locke solution. Analyzes were performed for immunohistochemical caspase, IL-8 and KI-67. Results The fractal dimension and Shannon entropy were not different between groups histidine-tryptophan-glutamate and histidine-tryptophan-acetoglutarate. Conclusion The amount of information measured by Shannon entropy and the distribution thereof (given by fractal dimension) of the slices treated with histidine-tryptophan-cetoglutarate and histidine-tryptophan-glutamate were not different, showing that the histidine-tryptophan-glutamate solution is as good as histidine-tryptophan-acetoglutarate to preserve myocytes in isolated rat heart.

Correção de aneurisma de ventrículo esquerdo em paciente chagásico empregando prótese de pericárdio bovino

The authors describe the surgical correction of left ventricle aneurysm in a female patient with Chagas disease that presented heart failure. A prosthesis of bovine pericardium was used to reconstruct the aneurysmatic wall of the left ventricle, thus obtaining marked reduction of symptoms. They believe that the benefits of this type of surgery in patients with left ventricle aneurysm of ischemic etiology, can be extended to patients with Chagas disease.

Surgical Treatment for Thrombus Straddling a Patent Foramen Ovale

We present a case of a 41-year-old female with deep vein thrombosis after abdominal surgery. The patient quickly developed severe pulmonary embolism and stroke representative of paradoxical embolism. Echocardiography showed a thrombus straddling a patent foramen ovale, which was confirmed intraoperatively. An accurate diagnosis and rapid treatment decisions are crucial for preventing patient deterioration in the form of new pulmonary embolisms or stroke.

Endnote Web tutorial for BJCVS/RBCCV

At present, many useful tools for reference management are available for use. They can be either off-line softwares or accessible Websites to all users in the internet. Their target is to facilitate the production of scientific text. But, to accomplish that, the featured bibliographic style should be effectively inserted, and the program has to be free. Here in this tutorial, we present Endnote Web®, a bibliographic reference management program comprising these two requirements: it contains the Brazilian Journal of Cardiovascular Surgery reference format and its use is free for charge after sign-in in IP registered terminal in Web of Science®.