Anderson Benício

Perspectivas da evolucão clínica de pacientes com cardiomiopatia chagásica listados em prioridade para o transplante cardíaco

INTRODUCTION: Heart failure is responsible for high mortality rates of patients on heart transplantation waiting lists. In Chagas cardiomyopathy, the presence of biventricular dysfunction increases the severity of this situation. METHOD: One hundred and forty-one patients suffering from cardiogenic shock, listed as high priority for heart transplantation, were studied. Forty-six patients presented with Chagas cardiomyopathy and 95 with other cardiomyopathies. Heart failure was treated using intravenous inotropic drugs and intra-aortic balloon pump implantation. Five patients with Chagas disease underwent paracorporeal left ventricular assist device implantation. RESULTS: During a mean follow-up of 2.8 months, 58 (41.1%) of the 141 patients were transplanted, while 73 (53.7%) died and 10 were removed from the waiting list. The mortality rates in chagasic and non-chagasic patients were 45.6% and 54.7%, respectively. The mean expected survival of patients with Chagas disease, who did not undergo heart transplantation, was only 1.5 months, with these patients presenting a relative risk for death of 1.6 compared to patients with other heart diseases (p<0.05). The five chagasic patients submitted to left ventricular assist device implantation were maintained on support for a mean of 22 days, with two of them undergoing transplantation, two died due to multiple organ failure and one remains on circulatory support. None of these patients presented right ventricular dysfunction and there were no device related complications. CONCLUSION: The evolution of heart failure seems to be rapid in patients with Chagas cardiomyopathy. Therefore, an early indication of mechanical circulatory support is important as a bridge to heart transplantation in these patients.

Reevaluation of long-term outcomes of dynamic cardiomyoplasty.

BACKGROUND Palliative procedures have been proposed for treatment of dilated cardiomyopathies. This study analyzes long-term outcomes of 43 patients who underwent dynamic cardiomyoplasty. METHODS Patients were in New York Heart Association class III (n = 35) or IV (n = 8) before the procedure. Hospital mortality was 2.2%, and patients were followed for 44 +/- 33 months. Thirty-nine patients completed the skeletal muscle adaptation period, and the muscle flaps were stimulated to contract in concert with every cardiac beat (n = 27) or with every other beat (n = 12). RESULTS One-year event-free survival was 81.3% +/- 5.9%; 2-year, 65.1% +/- 7.2%; 5-year, 34.7% +/- 7.2%; and 9-year, 10.8% +/- 5.3%. Causes of late deaths were equally divided between progressive heart failure and arrhythmia-related events. Multivariable Cox proportional hazard regression identified that functional class IV, high pulmonary vascular resistance, and muscle flap stimulation synchronized to every cardiac beat were independent predictors of poor event-free survival. The same factors were associated with the occurrence of progressive heart failure, but none was a predictor of arrhythmia-related deaths. Five-year survival of patients maintained with the muscle flap stimulated at every other cardiac beat was 58.3% +/- 14.2%. Skeletal muscle stimulation protocols also influenced the long-term behavior of left ventricular ejection fraction. CONCLUSIONS Long-term results of dynamic cardiomyoplasty are limited by the patients preoperative condition and by a high incidence of sudden cardiac death. These results may be improved using modified skeletal muscle stimulation protocols and cardioverter-defibrillator implantation, while maintaining dynamic cardiomyoplasty as an option for selected patients.

Ischemic preconditioning and spinal cord function monitoring in the descending thoracic aorta approach

OBJECTIVES To evaluate the effectiveness of acute ischemic preconditioning (IP), based on somatosensory evoked potentials (SSEP) monitoring, as a method of spinal cord protection and to asses SSEP importance in spinal cord neuromonitoring. METHODS Twenty-eight dogs were submitted to spinal cord ischemic injury attained by descending thoracic aorta cross-clamping. In the C45 group, the aortic cross-clamping time was 45 min (n=7); in the IP45 group, the dogs were submitted to IP before the aortic cross-clamping for 45 min (n=7). In the C60 group, the dogs were submitted to 60 min of aortic cross-clamping (n=7), as in the IP60 group that was previously submitted to IP. The IP cycles were determined based on SSEP changes. RESULTS Tarlov scores of the IP groups were significantly better than those of the controls (p = 0.005). Paraplegia was observed in 3 dogs from C45 and in 6 from C60 group, although all dogs from IP45 group were neurologically normal, as 4 dogs from IP60. There was a significant correlation between SSEP recovery time until one hour of aortic reperfusion and the neurological status (p = 0.011), showing sensitivity of 75% and specificity of 83%. CONCLUSION Repetitive acute IP based on SSEP is a protection factor during spinal cord ischemia, decreasing paraplegia incidence. SSEP monitoring seems to be a good neurological injury assessment method during surgical procedures that involve spinal cord ischemia.

Mixoma de átrio direito com origem na veia cava inferior: uma localização rara com implicações diagnósticas e terapêuticas

The myxomas are the most frequent primary cardiac tumors. They are usually located in the left atrium but can be found in other places. This is a case report of a 71 year old patient with diagnosis of a tumor arising from the right atrium, submitted to a surgical resection of the tumor. The operation was realized and the diagnosis confirmed. Resection was successful and the procedure uneventful. Four months postoperatively a standard two-dimensional echocardiogram revealed a residual mass that seemed to arise from the inferior vena cava. He was reoperated and the myxoma originating from the inferior vena cava and extending to the interior of the right atrium was resected. At the basis of the tumor implantation, a portion of the inferior vena cave was resected. The present report shows an unusual location of the myxoma as well as the complications regarding the diagnosis and the approach to surgical treatment.

Assistência circulatória mecânica: uma grande lacuna na cirurgia cardíaca brasileira

Devices for mechanical circulatory support have become, over recent years, the main parts in the treatment of cardiogenic shock and in the maintenance of circulatory support for patients with terminal heart failure. The use of these devices has been widely indicated as a bridge for subsequent heart transplantation, as supportive treatment for the recovery of the heart in acute myocardial infarction and postoperative cardiac surgery, or even to allow for ventricular recovery during rest obtained by prolonged mechanical circulatory support in patients with cardiomyopathies [1,2]. Additionally, mechanical devices to assist the left ventricle have been deployed in some countries, as destination therapy in the treatment of patients with terminal heart failure with contraindications to cardiac transplantation [1,2]. The development of cardiac surgery in Brazil has always been characterized by the incorporation of latest technologies and treatments in many different fields. In addition, the specialty currently includes a large number of procedures performed, mainly in the treatment of coronary disease [3,4]. Moreover, the use of mechanical assist devices has been limited in our country to support postoperative patients undergoing cardiac surgery by use of centrifugal pumps and some unique experiments with the use of cardiopulmonary bypass with membrane oxygenator (ECMO) in the postoperative period of pediatric cardiac surgery [5] or the treatment of cardiogenic shock after myocardial infarction [6]. Similarly, the use of mechanical assist devices as bridge to heart transplantation also can be summed up in few cases performed [7,8]. Despite the long history of heart transplantation in Brazil [9] and the promising results observed with this therapy, especially in the treatment of Chagas’ heart disease [10], a major limitation noted for the results of this procedure is the high mortality observed in the waiting list. Data from the State System of Transplantation of São Paulo showed that 50% of patients listed for heart transplantation over the past five years died on the waiting list. The incidence of cardiogenic shock due to progressive circulatory failure Luiz Felipe Pinho MOREIRA1, Anderson BENÍCIO2

Avaliação do desempenho hemodinâmico do dispositivo de assistência ventricular InCor como substituto do coração esquerdo

BACKGROUND: The mechanical circulatory assistance is a therapeutic option in cases of cardiogenic shock refractory to the pharmacological treatment, and is frequently used as a bridge for heart transplantation. OBJECTIVE: To evaluate the action of the Ventricular Assist Device (VAD) developed by the Bioengineering Division of the Instituto do Coracao, implanted as a substitute of the left heart. PATIENTS AND METHODS: Ten Girolando calves with medium weight of 73 kg were studied. The VAD-InCor implant was accomplished with the drainage cannula positioned in the left atrium (LA) or in the apex of the left ventricle and the replacement cannula implanted in the descending thoracic aorta. The pressures of the right and left heart, cardiac output and the flow of VAD were determined before and after the pharmacological induction of myocardial failure, at different levels of vacuum of the drainage system. RESULTS: Values of the flow of VAD with the drainage in LA were of 2.2 ± 0.5 l/min without vacuum, of 3.7 ± 0.4 with vacuum of 10 mmHg, of 4.3 ± 0.4 with vacuum of 20 mmHg and of 4.8 ± 0.6 with vacuum of 30 mmHg. The values of the pressure of LA were: 11.7 ± 6; 9.8 ± 5.3; 8.5 ± 4.4 and 5.6 ± 3.3 mmHg under the same conditions, respectively. With the ventricular cannula, the VAD flow was 4.2 ± 0.6 without vacuum and of 4.4 ± 0.7 with vacuum of 10 mmHg, with of LA pressure of 11.1 ± 2 and 10.3 ± 3.5 mmHg in the two conditions. Those results were observed in similar hemodynamic conditions, with the VAD flow responsible for a greater percentile of the total cardiac output according to the level of vacuum. That percentile was of 86 ± 13% with the atrial cannula and vacuum of 30 mmHg and of 97 ± 3% with the ventricular drainage and vacuum of 10 mmHg. CONCLUSIONS: The VAD-InCor demonstrated its effectiveness as a substitute of the left heart. The performance of this device was proportional to the level of vacuum of the drainage system and was better with the ventricular cannula.

Intrathecal injection of human umbilical cord blood stem cells attenuates spinal cord ischaemic compromise in rats

OBECTIVES Spinal cord ischaemia with resulting paraplegia remains a devastating and unpredictable complication after thoraco-abdominal aortic surgery. With the advent of stem cell therapy and its potential to induce nervous tissue regeneration processes, the interest in the use of these cells as a treatment for neurological disorders has increased. Human stem cells, derived from the umbilical cord, are one of the strong candidates used in cell therapy for spinal cord injury because of weak immunogenicity and ready availability. We sought to evaluate the use of human umbilical cord blood stem cells (HUCBSCs) to attenuate the neurological effects of spinal cord ischaemia induced by high thoracic aorta occlusion. METHODS Forty Wistar rats were randomized to receive intrathecal injection of 10 µl phosphate buffered saline (PBS) solution containing 1 × 10(4) HUCBSCs, 30 min before (Tpre group: n = 10) and 30 min after (Tpos group: n = 10) descending thoracic aorta occlusion by intraluminal balloon during 12 min. Control groups received only PBS solution (Cpre group: n = 10; and Cpos group: n = 10). During a 28-day observational period, motor function was assessed by a functional grading scale (Basso, Beattie and Bresnahan). Segments of thoracolumbar spinal cord specimens were analysed for histological and immunohistochemical assessment for detection and quantification of human haematopoietic cells (CD45(+)) and apoptosis (transferase-mediated deoxyuridine triphosphate-biotin nick-end labelling). RESULTS Overall mortality was 12 animals (30%). Therefore, the observational sample was composed of 28 animals. All groups showed similar incidence of paraplegia and mortality. The mean motor function scores showed no difference during time between the animals of each group, excepting for the Tpos group, which improved from 8.14 (±8.6) to 14.28 (±9.8) (P < 0.01). A treatment-by-time interaction was detected among animals that received HUCBSCs 30 min after ischaemia, with BBB scores higher from Days 14 to 28 compared with the first observational day with statistical difference (P = 0.01). Number of viable neurons was higher in the Tpos group (P = 0.14) and the incidence of apoptosis was lower in the same animals (P = 0.048), but showed no difference with its respective control. We confirmed the presence of CD45(+) cells 4 weeks after intrathecal injection in both therapeutic groups but mainly in the Tpos group. CONCLUSIONS Intrathecal transplantation of HUCBSCs is feasible, and it improved spinal cord function, when they were delivered 30 min after spinal cord ischaemia, in a model of endovascular descending thoracic aorta occlusion in rats. Human umbilical cord blood is one of the potentially useful sources of stem cells for therapy of spinal cord ischaemia.

Cirurgia robótica em Cardiologia: um procedimento seguro e efetivo

OBJECTIVE: To evaluate the short and medium-term outcomes of patients undergoing robotic-assisted minimally invasive cardiac surgery. METHODS: From March 2010 to March 2013, 21 patients underwent robotic-assisted cardiac surgery. The procedures performed were: mitral valve repair, mitral valve replacement, surgical correction of atrial fibrillation, surgical correction of atrial septal defect, intracardiac tumor resection, totally endoscopic coronary artery bypass surgery and pericardiectomy. RESULTS: The mean age was 48.39±18.05 years. The mean cardiopulmonary bypass time was 151.7±99.97 minutes, and the mean aortic cross-clamp time was 109.94±81.34 minutes. The mean duration of intubation was 7.52±15.2 hours, and 16 (76.2%) patients were extubated in the operating room immediately after the procedure. The mean length of intensive care unit stay was 1.67±1.46 days. There were no conversions to sternotomy. There was no in-hospital death or deaths during the medium-term follow-up. Patients mean follow up time was 684±346 days, ranging from 28 to 1096 days. CONCLUSION: Robotic-assisted cardiac surgery proved to be feasible, safe and effective and can be applied in the correction of various intra and extracardiac pathologies.ABSTRACT Objective: To evaluate the short and medium-term outcomes of patients undergoing robotic-assisted minimally invasive cardiac surgery. Methods: From March 2010 to March 2013, 21 patients underwent robotic-assisted cardiac surgery. The procedures performed were: mitral valve repair, mitral valve replacement, surgical correction of atrial fibrillation, surgical correction of atrial septal defect, intracardiac tumor resection, totally endoscopic coronary artery bypass surgery and pericardiectomy. Results: The mean age was 48.39±18.05 years. The mean cardiopulmonary bypass time was 151.7±99.97 minutes, and the mean aortic cross-clamp time was 109.94±81.34 minutes. The mean duration of intubation was 7.52±15.2 hours, and 16 (76.2%) patients were extubated in the operating room immediately after the procedure. The mean length of intensive care unit stay was 1.67±1.46 days. There were no conversions to sternotomy. There was no in-hospital death or deaths during the medium-term follow-up. Patients mean follow up time was 684±346 days, ranging from 28 to 1096 days. Conclusion: Robotic-assisted cardiac surgery proved to be feasible, safe and effective and can be applied in the correction of various intra and extracardiac pathologies.

Cavo-pulmonary anastomosis associated with left ventricular in comparison with biventricular circulatory support in acute heart failure

OBJECTIVE Right ventricular (RV) failure during left ventricular assist device (LVAD) support can result in severe hemodynamic compromise with high mortality. This study investigated the acute effects of cavo-pulmonary anastomosis on LVAD performance and RV myocardial compromise in comparison with biventricular circulatory support, in a model of biventricular failure. METHODS LVAD support was performed by centrifugal pump in 21 pigs with severe biventricular failure obtained by FV induction. Animals were randomized to be submitted to cavo-pulmonary anastomosis, to biventricular circulatory support or to control group. They were maintained under circulatory support and hemodynamic monitoring for 3h. Venous lactate and cytokines serum levels were also obtained. Endocardium samples were analyzed by electronic microscopy. RESULTS FV maintenance was responsible for acute LVAD impairment after 180 min in the control group. cavo-pulmonary anastomosis resulted in non-significant improvement of LVAD pump flow in relation to control group (+55±14 ml/kg/min, P=0.072), while animals under biventricular support maintained higher LVAD flow (+93±17 ml/kg/min, P=0.012). Mean arterial pressure remained constant only in biventricular group (P<0.001), which also presented decrease of right atrial and ventricular pressures. Similar increases in lactate and cytokines levels were observed in the three groups. Ultra-structural analysis documented low levels of myocardial swelling in the biventricular group (P=0.017). CONCLUSION The concomitant use of cavo-pulmonary anastomosis during LVAD support in a pig model of severe biventricular failure resulted in non-significant improvement of hemodynamic performance and it did not effectively replace the use of biventricular support.

Lung Perfusion and Ventilation During Cardiopulmonary Bypass Reduces Early Structural Damage to Pulmonary Parenchyma.

BACKGROUND:It is unclear whether maintaining pulmonary perfusion and ventilation during cardiopulmonary bypass (CPB) reduces pulmonary inflammatory tissue injury compared with standard CPB where the lungs are not ventilated and are minimally perfused. In this study, we tested the hypothesis that maintenance of lung perfusion and ventilation during CPB decreases regional lung inflammation, which may result in less pulmonary structural damage. METHODS:Twenty-seven pigs were randomly allocated into a control group only submitted to sternotomy (n = 8), a standard CPB group (n = 9), or a lung perfusion group (n = 10), in which lung perfusion and ventilation were maintained during CPB. Hemodynamics, gas exchanges, respiratory mechanics, and systemic interleukins (ILs) were determined at baseline (T0), at the end of 90 minutes of CPB (T90), and 180 minutes after CPB (T180). Bronchoalveolar lavage (BAL) ILs were obtained at T0 and T180. Dorsal and ventral left lung tissue samples were examined for optical and electron microscopy. RESULTS:At T90, there was a transient reduction in PaO2/FIO2 in CPB (126 ± 64 mm Hg) compared with the control and lung perfusion groups (296 ± 46 and 244 ± 57 mm Hg; P < 0.001), returning to baseline at T180. Serum ILs were not different among the groups throughout the study, whereas there were significant increases in BAL IL-6 (P < 0.001), IL-8 (P < 0.001), and IL-10 (P < 0.001) in both CPB and lung perfusion groups compared with the control group. Polymorphonuclear counts within the lung tissue were smaller in the lung perfusion group than in the CPB group (P = 0.006). Electron microscopy demonstrated extrusion of surfactant vesicles into the alveolar spaces and thickening of the alveolar septa in the CPB group, whereas alveolar and capillary histoarchitecture was better preserved in the lung perfusion group. CONCLUSIONS:Maintenance of lung perfusion and ventilation during CPB attenuated early histologic signs of pulmonary inflammation and injury compared with standard CPB. Although increased compared with control animals, there were no differences in serum or BAL IL in animals receiving lung ventilation and perfusion during CPB compared with standard CPB.