RESUMEN
We report the case of an 8-month-old female infant with Uhl's anomaly, who underwent successful cardiac transplantation. The clinical findings, complementary laboratory tests, anatomic findings, and differential diagnosis of the anomaly are discussed.
Asunto(s)
Cardiopatías Congénitas/diagnóstico , Trasplante de Corazón/métodos , Ventrículos Cardíacos/anomalías , Diagnóstico Diferencial , Femenino , Cardiopatías Congénitas/patología , Cardiopatías Congénitas/cirugía , Humanos , LactanteRESUMEN
We report two cases of congenital atresia of the ostium of the left coronary artery. Case 1: a six-month-old infant presenting with serious cardiac insufficiency. A noninvasive diagnosis of dilated myocardiopathy was established and the clinical picture was pharmacologically compensated. When the patient was nine months of age, a hemodynamic study was performed that revealed congenital atresia of the ostium of the left coronary artery; the infant immediately underwent a successful anastomosis of the internal mammary artery with the left coronary artery. Case 2: an eleven-year-old asymptomatic boy with a history of heart murmur from the age of six months on, was referred for surgery with a diagnosis of anomalous origin of the left coronary artery from pulmonary trunk. A definitive diagnosis of atresia of the left coronary ostium was only established during surgery. Successful surgical revascularization with the left internal mammary artery, and left ventricular aneurysmectomy were performed.
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Anomalías de los Vasos Coronarios/cirugía , Anastomosis Interna Mamario-Coronaria , Niño , Anomalías de los Vasos Coronarios/diagnóstico , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Electrocardiografía , Estudios de Seguimiento , Humanos , Lactante , Masculino , Radiografía , Resultado del TratamientoRESUMEN
OBJECTIVE: To assess intermediate-term outcome in children who have undergone orthotopic heart transplantation. METHODS: We carried out a longitudinal and prospective study between October '92 and June '99 comprising 20 patients with ages ranging from 12 days to 7 years (mean of 2.8 years). We employed a double immunosuppression protocol with cyclosporine and azathioprine and induction therapy with polyclonal antithymocyte serum. Survival and complications resulting from the immunosuppression protocol were analyzed. RESULTS: The double immunosuppression protocol and the induction therapy with polyclonal antithymocyte serum resulted in an actuarial survival curve of 90% and 78.2% at 1 and 6 years, respectively, with a mean follow-up period of 3.6 years. One patient died due to acute rejection 40 days after transplantation; another patient died 2 years after transplantation due to lymphoproliferative disorder; a third patient died because of primary failure of the graft; and a fourth patient died due to bronchopneumonia. The major complications were as follows: acute rejection, infection, nephrotoxicity, and systemic hypertension. The means of rejection and infection episodes per patient were 2.9 and 3.4, respectively. After one year of transplantation, a slight reduction in the creatinine clearance and systemic hypertension were observed in 7 (38.9%) patients. CONCLUSION: Heart transplantation made life possible for those patients with complex congenital heart diseases and cardiomyopathies in refractory congestive heart failure constituting a therapeutical option for this group of patients in the terminal phase.
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Trasplante de Corazón/mortalidad , Cardiomiopatías/cirugía , Niño , Preescolar , Femenino , Estudios de Seguimiento , Rechazo de Injerto/diagnóstico , Cardiopatías Congénitas/cirugía , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/efectos adversos , Humanos , Terapia de Inmunosupresión/efectos adversos , Terapia de Inmunosupresión/métodos , Lactante , Recién Nacido , Estudios Longitudinales , Masculino , Estudios Prospectivos , Análisis de SupervivenciaRESUMEN
In this report we describe the twelfth case in the literature of absence of the aortic valve cusps, associated with hypoplastic left-sided heart syndrome in a neonate. Clinical and hemodynamic conditions in our patient resemble the classical features of this syndrome except for a greater development of the ascending aorta and the left ventricular cavity, due to aortic insufficiency. A patch was unsuccessfully inserted at the aortic annulus to exclude the left ventricle from the circulation. In addition the Norwood operation was performed.
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Válvula Aórtica/anomalías , Síndrome del Corazón Izquierdo Hipoplásico/diagnóstico , Resultado Fatal , Humanos , Síndrome del Corazón Izquierdo Hipoplásico/cirugía , Recién Nacido , MasculinoRESUMEN
OBJECTIVE: We sought to assess the rapid hypertrophy of the right ventricle of young goats submitted to progressive pressure load by a balloon catheter. METHODS: The hearts of 6 young goats were assessed by means of echocardiography and cell morphology during and after right ventricular hypertrophy had been produced by a balloon catheter. Myocardial samples of the right ventricular outflow tract were harvested for microscopic studies. The external diameter of longitudinally sectioned myocytes was measured at the nucleus level. The volume density of mitochondria was also determined. A balloon catheter was then placed through the right ventricular outflow tract in the pulmonary trunk and progressively inflated every 2 days. Postoperative serial echocardiography was performed at intervals of 1 to 2 days. The animals were killed after 2 to 3 weeks of right ventricular training for morphologic analysis. RESULTS: Under optical microscopy, there was a 20.5% increase in the mean diameter of the myocyte of the trained right ventricle. However, under electron microscopy, there was no significant change in the mean volume density of mitochondria from the trained right ventricle. Serial echocardiography showed equalization of the ventricular thickness over a short interval of 6 to 10 days of progressive balloon inflation. CONCLUSIONS: The balloon catheter permits the manipulation of the pressure load over the right ventricle, causing rapid hypertrophy in a 6- to 10-day period. This study suggests that nonsurgical preparation of the "pulmonary ventricle" in patients with transposition of great arteries with intact ventricular septum beyond the neonatal period could probably be accomplished within a very few days.
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Cateterismo , Hipertrofia Ventricular Derecha/etiología , Arteria Pulmonar , Animales , Gota , Hipertrofia Ventricular Derecha/diagnóstico por imagen , Hipertrofia Ventricular Derecha/patología , Factores de Tiempo , UltrasonografíaAsunto(s)
Coartación Aórtica/cirugía , Coartación Aórtica/diagnóstico , Coartación Aórtica/fisiopatología , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Hipertensión/etiología , Lactante , Imagen por Resonancia Magnética , Persona de Mediana Edad , Complicaciones Posoperatorias , Recurrencia , Función Ventricular IzquierdaRESUMEN
OBJECTIVE: The objective of this paper is to report our experience with biventricular repair of double-outlet right ventricle with noncommitted ventricular septal defect by means of multiple patches that simplify and render feasible the intraventricular correction of this complex anomaly. METHODS: From April 1987 to April 1999, in 18 patients with double-outlet right ventricle and noncommitted ventricular septal defect, a technical modification that used multiple patches of bovine pericardium was used to construct an intraventricular tunnel connecting the left ventricle to the aorta. Ages ranged from 2 months to 13 years (mean age 4.73 +/- 3.41 years). RESULTS: The early mortality was of 11.1% (2 patients). Surviving patients were followed up for a mean of 2.65 years. Three late deaths (16.6%) occurred: 5 months, 7 months, and 7 months after the operation. All but 1 patient are in New York Heart Association class I. CONCLUSION: The use of multiple patches for biventricular correction of this anomaly simplifies and renders feasible the intraventricular repair in cases in which the 1-patch technique was deemed impossible.
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Ventrículo Derecho con Doble Salida/cirugía , Defectos del Tabique Interventricular/cirugía , Pericardio/trasplante , Adolescente , Animales , Aorta/cirugía , Bovinos , Niño , Preescolar , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Cardiopatías Congénitas/complicaciones , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Complicaciones Posoperatorias , Arteria Pulmonar/cirugía , Estudios Retrospectivos , Tasa de Supervivencia , Trasplante Heterólogo , Válvula Tricúspide/cirugíaRESUMEN
OBJECTIVE: Anomalous origin of the left coronary artery from the right pulmonary artery (AOLCARPA), is a rare entity that is usually associated with other defects. Of the 20 cases of AOLCARPA reported in the literature, 14 (70%) had associations. We describe four patients with AOLCARPA without associated defects, but with a peculiar intramural aortic trajectory. METHODS: Fifty-five patients with anomalous origin of the left coronary artery were operated upon at INCORFMUSP. Four of the patients had the anomalous origin from the right pulmonary artery (RPA) without associated defects but with intramural aortic trajectory. Clinical and laboratory examinations were analyzed, as well as surgical findings. RESULTS: All patients had congestive heart failure (CHF) and 3 also had angina pectoris. Two patients had a murmur of mitral regurgitation, signs of myocardial infarction on the ECG and cardiomegaly. The shortening fraction varied from 9% to 23%. The hemodynamic study confirmed the diagnosis of anomalous origin of the coronary artery, but the intramural trajectory and the origin from the RPA were established only at surgery. In 3 patients, the technique of side-to-side anastomosis was performed with a good outcome. One patient, who underwent end-to-side anastomosis, died 6 months after the surgery. CONCLUSION: Association with other defects usually occurs in the AOLCARPA, and the intramural aortic trajectory is difficult to clinically diagnose but easy to surgically correct.
Asunto(s)
Anomalías de los Vasos Coronarios/patología , Arteria Pulmonar/anomalías , Adolescente , Aorta Torácica/anomalías , Niño , Preescolar , Femenino , Humanos , Masculino , Arteria Pulmonar/cirugíaRESUMEN
OBJECTIVE: To assess neonates with aortic stenosis with early decompensation operated upon. (LCO) (CHF). METHODS: A and retrospective study analyzing 6 neonates with LCO, group I (GI), and 12 neonates with CHF, group II (GII). Clinical radiographic, electrocardiographic and echocardiographic findings also provided comparative bases for the study, as did surgical and evolutional findings. RESULTS: The mean ages at hospitalization and surgery (p = 0.0031) were 14.3 and 14.8 days in GI and 35.4 and 42.8 days in GII, respectively. Cardiac murmurs were more intense in GII (p = 0.0220). The aortic ring was smaller in GI (8.0 +/- 2.5mm) as compared to GII (11.4 +/ 1.4mm) (p = 0.2882). Ventricular function was reduced to 18 +/- 5.5% and 33.3 +/- 7.6% in GI and GII, respectively (p = 0.0162). Aortic atresia, however, was present only in 2 neonates in GI. Five of 6 patients in GI died but all patients in GII survived (p=0.0007). In the latter group, 84.6% of the patients were in functional class I (FC-I) in the long-term follow-up, with moderate residual lesions in 6 neonates, discrete residual lesions in 4, and reoperation in 2. CONCLUSION: Aortic stenosis is a severe anomaly of the neonate, whose immediate evolution depends on the pre-operative anatomic and functional findings, and the late evolution essentially depends on the anatomic features of the valve.
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Estenosis de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/congénito , Estenosis de la Válvula Aórtica/cirugía , Gasto Cardíaco Bajo/fisiopatología , Femenino , Insuficiencia Cardíaca/fisiopatología , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Estudios Retrospectivos , Estadísticas no Paramétricas , Resultado del TratamientoRESUMEN
OBJECTIVE: The aim of this work was the follow-up and evaluation of valve replacement in children under 12 years of age. METHODS: Forty-four children less than 12 years old were underwent valve replacement at INCOR-HCFMUSP between January 1986 and December 1992. Forty (91%) were rheumatic, 39 (88.7%) were in functional classes II or IV, 19 (43.2%) were operated upon on an emergency basis, and 6 (13.6%) had atrial fibrillation. Biological prostheses (BP) were employed in 26 patients (59.1%), and mechanical prostheses (MP) in 18 (40.9%). Mitral valves were replaced in 30 (68.7%), aortic valves in 8 (18.2%), a tricuspid valve in 1 (2.3%), and double (aortic and mitral) valves in 5 (11.4) of the patients. RESULTS: Hospital mortality was of 4.5% (2 cases). The mean follow-up period was 5.8 years. Re-operations occurred in 63.3% of the patients with BP and in 12.5% of those with MP (p=0.002). Infectious endocarditis was present in 26.3% of the BP, but in none of the cases of MP (p=0.049). Thrombosis occurred in 2 (12.5%) and hemorrhage in one (6.5%) of the patients with a MP. Delayed mortality occurred in 5 (11.9%) of the patients over a mean period of 2.6 years; four had had BP and one had a MP (NS). Actuarial survival and re-operation-free curves after 10 years were respectively, 82.5+/-7.7 (SD)% and 20.6+/-15.9%. CONCLUSION: Patients with MP required fewer re-operation, had less infectious endocarditis and lower late mortality rates compared with patients with bioprostheses. The former, therefore, appear to be the best valve replacement for pediatric patients.
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Enfermedades de las Válvulas Cardíacas/cirugía , Prótesis Valvulares Cardíacas/efectos adversos , Fibrilación Atrial/cirugía , Bioprótesis , Niño , Preescolar , Femenino , Estudios de Seguimiento , Enfermedades de las Válvulas Cardíacas/etiología , Enfermedades de las Válvulas Cardíacas/mortalidad , Humanos , Masculino , Reoperación , Estudios Retrospectivos , Fiebre Reumática/complicaciones , Resultado del TratamientoRESUMEN
OBJECTIVE: Aortopulmonary window (APW) is an uncommon congenital malformation. Its clinical presentation is dependent on the size of the defect and on the associated lesions. We evaluated our experience with this anomaly and compared it with 296 cases reported in the literature. METHODS: Retrospective study of 18 patients diagnosed as having APW (age range from 13 days to 31 years, 13 (72.2%) females), divided into two groups: Group A (GA): 10 patients with isolated APW, and Group B (GB): 8 patients with associated lesions. RESULTS: Heart failure occurred in 14 patients, and cyanosis in 3:2 from GB (tetralogy of Fallot--TF, and double outlet right ventricle--DORV), and one from GA with pulmonary hypertension. In 5 patients from GA the diagnosis of mitral regurgitation was made based on a systolic murmur and LV hypertrophy on the EKG. In GB, clinical findings were determined by the associated defect. Diagnosis was established by echocardiography in 11 (61.2%) of the patients. In 3 patients, a wrong diagnosis of mitral regurgitation was made, in 1 a patent ductus arteriosus was diagnosed and in 3 others, the diagnosis of APW was masked by other important associated defects (2 cases of DORV and 1 case of TF). The diagnosis was made by catheterization in 3 (16.6%) patients, by surgery in 3 (16.6%) and by necropsy in 1 (5.5%). Corrective surgery was performed in 14 (77.7%) patients, with one immediate death and good long-term follow-up in the remaining patients. CONCLUSION: APW can be confused with other defects. Clinical findings, associated with an adequate echocardiogram can provide the information for the correct diagnosis.
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Defecto del Tabique Aortopulmonar , Adolescente , Adulto , Defecto del Tabique Aortopulmonar/diagnóstico , Defecto del Tabique Aortopulmonar/fisiopatología , Defecto del Tabique Aortopulmonar/cirugía , Niño , Preescolar , Ecocardiografía Doppler en Color , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Eleven children, 4-48 months old, with congenital cyanotic heart defects developed choreoathetoid movements 2-12 days after cardiac surgery with hypothermia and extracorporeal circulation (ECC). The abnormal movements mainly involved the limbs, facial musculature, and tongue, leading to a severe dysphagia. The symptoms had an acute onset, after a period of apparent neurologic normality, and had a variable outcome. Of the nine children that survive, three had abnormal movements when last seen (41 days to 12 months of follow-up). The other six children had a complete regression of the choreoathetoid movements 1-4 weeks after onset. No specific finding was observed in the CT scans, cerebrospinal fluid examination, or EEG that could be related to the abnormal movements. Symptomatic therapy with haloperidol with or without benzodiazepines led to symptomatic improvement in six children, although there was no evidence that this treatment modified the evolution of the disease. The authors conclude that the choreoathetoid syndrome after cardiac surgery with deep hypothermia and ECC is an ill-defined entity requiring additional study to better understand its pathogenesis so that preventive measures can be taken to avoid a condition that can lead to permanent and incapacitating neurologic sequelae.
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Atetosis/etiología , Procedimientos Quirúrgicos Cardíacos , Corea/etiología , Circulación Extracorporea , Hipotermia Inducida , Complicaciones Posoperatorias , Adolescente , Antidiscinéticos/uso terapéutico , Atetosis/tratamiento farmacológico , Benzodiazepinas/uso terapéutico , Corea/tratamiento farmacológico , Electroencefalografía , Femenino , Haloperidol/uso terapéutico , Humanos , Lactante , Masculino , Cuidados Posoperatorios , Complicaciones Posoperatorias/mortalidad , Periodo PosoperatorioRESUMEN
BACKGROUND: Interest in minimally invasive procedures has recently increased because it results in less surgical trauma, decreased patient discomfort, short hospital stay, reduced costs, and better cosmetic appearance. Based on these facts, we have been using the transxiphoid process approach without sternotomy for the correction of atrial septal defects. METHODS: From July 1996 to January 1997, the xiphoid process window approach was performed in 10 patients with ostium secundum atrial septal defect. Ages ranged from 6 months to 14 years (mean, 5.3 years). In all patients, extracorporeal circulation was carried out by means of cannulation of the femoral artery and both caval veins and of aortic cross-clamping. Videothoracoscopy was used to improve visualization of the aorta. RESULTS: There were no intraoperative or postoperative complications, and in all but 1 patient, extubation was possible while in the operating room. CONCLUSIONS: The xiphoid process window, with no median sternotomy, permitted closure of the atrial septal defects with good results and could be used as a less invasive technique for their correction.
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Defectos del Tabique Interatrial/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Adolescente , Niño , Preescolar , Circulación Extracorporea/métodos , Femenino , Humanos , Lactante , Masculino , Apófisis XifoidesAsunto(s)
Tronco Arterial Persistente/cirugía , Factores de Edad , Prótesis Vascular , Preescolar , Prótesis Valvulares Cardíacas , Mortalidad Hospitalaria , Humanos , Lactante , Selección de Paciente , Pronóstico , Factores de Riesgo , Tronco Arterial Persistente/clasificación , Tronco Arterial Persistente/complicaciones , Tronco Arterial Persistente/mortalidadRESUMEN
OBJECTIVE: Introduce a new surgical technique for biventricular correction of double-outlet right ventricle with noncommitted ventricular septal defect. METHODS: From April 1987 to February 1996, 15 patients with double-outlet right ventricle with noncommitted ventricular septal defect were operated on using a new technique for biventricular repair with multiple bovine pericardial patches to create a tunnel between the left ventricle and the aorta. Ages ranged from two months to 13 years (mean age 4.8 years). Thirteen patients had situs solitus and levocardia, one patient had situs inversus and dextrocardia, and one patient had situs solitus and dextrocardia. Construction of the tunnel began at the right atrium. The ventricular septal defect (VSD) was enlarged anteriorly, if restrictive or small, and the first patch was sutured in the infero-posterior edge of the VSD. The second, third and sometimes the fourth patches were sutured in sequence, through the right ventriculotomy, directing the tunnel to the aortic annulus. RESULTS: Overall mortality was 20%, with two early and one late death. The surviving patients were followed-up for a period ranging from ten months to nine years (mean 33 months), and all were in functional class I (NYHA). Minimal residual ventricular septal defect was observed in one patient, stenosis in two patients and moderate pulmonary insufficiency in one. There was no obstruction of the intraventricular tunnel between the LV and the aorta. CONCLUSION: Based on these data, we conclude that this technical modification for the biventricular repair of the double-outlet right ventricle with noncommitted VSD allows for the construction of a tunnel with adequate internal diameter, respecting the spatial changes between the VSD and aorta. In addition, the intraventricular bovine pericardial tunnel takes up less space, thus reducing the incidence of right ventricle outlet obstruction.
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Procedimientos Quirúrgicos Cardíacos/mortalidad , Procedimientos Quirúrgicos Cardíacos/métodos , Ventrículo Derecho con Doble Salida/cirugía , Defectos del Tabique Interventricular/cirugía , Colgajos Quirúrgicos , Adolescente , Cateterismo Cardíaco , Niño , Preescolar , Ventrículo Derecho con Doble Salida/complicaciones , Ventrículo Derecho con Doble Salida/diagnóstico , Ecocardiografía Transesofágica , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Defectos del Tabique Interventricular/complicaciones , Defectos del Tabique Interventricular/diagnóstico , Humanos , Lactante , Masculino , Estudios Retrospectivos , Sensibilidad y Especificidad , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
PURPOSE: Heart transplantation has offered children with complex congenital heart diseases and severe cardiomyopathies a chance for survival. The present article was written to show the three year experience of this procedure at the Instituto do Coração-HCFMUSP. METHODS: The methodology used was based on heart transplant indication criteria, inclusion criteria for donors, postoperative management, immunosuppression and prophylaxis as well as treatment of potential complications. RESULTS: From November 1992 to November 1995, 11 children, aged 12 days old to six years (mean 2.5 years) underwent transplantation. Sixty percent of recipients were male; weight ranged from 3.5 to 17.8 kg (mean 10.3 kg). The mean age of donors was 4.4 years (a range of three weeks to ten years), 80% male, weight ranging from 3.8 to 20 kg (median 14.3 kg). The survival rate was 91% and the remaining 10 children are doing well. The most important complications were systemic hypertension, acute rejection and infection. The number of rejections and infections per patient were 3.5 and 4.7 episodes, respectively. The follow-up was between one month to three years (average 16 months). CONCLUSION: In this experience, heart transplantation has given an additional opportunity for children with complex congenital heart diseases and cardiomyopathies, with a survival rate of 91% in three years.
Asunto(s)
Trasplante de Corazón , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Complicaciones Posoperatorias , Periodo PosoperatorioRESUMEN
PURPOSE: To evaluate the clinical and surgical experience with consecutive patients with isolated total anomalous pulmonary venous connection admitted to the Heart Institute, São Paulo, Brasil. METHODS: Hospital records of 70 consecutive patients (January 1985 to December 1993) were retrospectively reviewed. There were 28 girls and 42 boys whose ages ranged from two days to four years (mean 20.4 +/- 29 weeks). The following variables were selected for analysis: anatomic type, age at admission, clinical status, the presence of infection, restrictive atrial septal defect, and the presence of pulmonary venous obstruction. Univariate and multivariate analysis were used to identify possible risk factors for death. RESULTS: The abnormal anatomical connection was supracardiac in 63%, cardiac in 17%, infracardiac in 8.5% and mixed in 11.5% of the cases. Eighteen (25.7%) patients were admitted in poor clinical condition. Infection, mainly pulmonar, was present in 31 (44%) patients. Pulmonary venous obstruction was present in 21% of the patients. Atrial septostomy was performed in 38 patients, 13 of them admitted in a poor clinical status. The preoperative mortality was 15.7% and the operative, 17%. Statistical analysis demonstrated that infection, poor clinical status and age were risk factors for death. CONCLUSION: Surgical correction of total anomalous pulmonary venous drainage in infancy can be performed at low risk with good results. However early referral to a cardiac care center, agressive preoperative stabilization and postoperative care are important.
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Venas Pulmonares/anomalías , Distribución de Chi-Cuadrado , Preescolar , Femenino , Mortalidad Hospitalaria , Humanos , Lactante , Recién Nacido , Masculino , Complicaciones Posoperatorias , Venas Pulmonares/cirugía , Estudios Retrospectivos , Factores de Riesgo , Estadísticas no ParamétricasRESUMEN
The heart is the most commonly affected organ in chronic Chagas' disease, and lymphocytic myocarditis is often observed. However, the pathogenesis of chronic Chagas' heart disease is controversial. The purpose of this study was to determine whether in vivo T. cruzi antigens could be detected in hearts from patients with chronic Chagas' disease and to investigate whether a correlation between these antigens and the intensity of myocardial inflammation exists. We studied 16 patients with chronic Chagas' heart disease. Ten patients had severely impaired left ventricular function and refractory heart failure, and six had episodes of sustained ventricular tachycardia without severe left ventricular dysfunction. Eight patients underwent magnetic resonance imaging with gadolinium enhancement to guide endomyocardial and surgical biopsies to sites with more intense inflammatory processes. Myocardial specimens were studied with immunohistochemical techniques by using rabbit anti-T. cruzi immune serum to detect the presence of T. cruzi antigen. All patients had evidence of some myocarditis in at least one myocardial fragment. T. cruzi antigen was detected in 11 (69%) patients. T. cruzi antigens were detected in 10 (71%) of 14 regions with histopathologic evidence of moderate or severe myocarditis. In contrast, T. cruzi antigens were detected in 3 of 18 regions with only mild or absent myocarditis. There was a statistically significant correlation between the presence of T. cruzi antigens and moderate or severe myocarditis (chi-square = 5.169, p = 0.023). The results of this in vivo study demonstrate that T. cruzi antigens are frequently detected in chronic Chagas' heart disease. In addition, there is an association between the intensity of the inflammatory process and the presence of T. cruzi antigens. The presence of the T. cruzi antigen and its correlation with the severity of myocardial inflammatory process provide strong supportive evidence for the role of T. cruzi even in the chronic forms of Chagas' heart disease.