[Influence of the referring health care systems and other factors on the results of mitral valve replacement]. / Influencia del sistema de salud de procedencia y otros factores en el resultado del reemplazo valvular mitral.

BACKGROUND: There is no consensus regarding which risk factors influence the outcome of mitral valve replacement. AIM: To study the effects of the referring health care system and other factors on the results of mitral replacement. PATIENTS AND METHODS: We included 632 patients operated between 1990 and 2010 receiving the St Jude prosthesis. Patients were divided into three groups, group 1 composed by 180 patients coming from the Public System, group 2 composed by 182 patients coming from the University System and group 3 composed by 270 patients coming from the Private System. RESULTS: Overall operative mortality was 4.3%. There was no difference between groups in mortality. Factors responsible for operative mortality were: emergency operation (Odds Patio (OR): 5.6 P < 0.01) and left ventricular function (according to ejection fraction) grade III to IV (OR: 2.5 p = 0.048). Actuarial survival rates at 1, 5, 10, 15 and 20 years were 95%, 87%, 76%, 61% and 41%, respectively. Risk factors for long-term mortality were diabetes (OR: 3.3 p < 0.01), left ventricular function grades III-IV (OR: 2.6 p < 0.01), New York Heart Association functional class III to PV (OR: 2.1 p < 0.005) and male sex (OR: 1.5 p < 0.032). CONCLUSIONS: Referring health care system and type of surgery do not constitute a risk factor for mitral replacement. Risk factors were: emergency surgery, ventricular function grades III-IV, diabetes, functional capacity class III-IV and male sex. Integration of public and private health care systems in a university hospital setting achieves excellent outcomes for complex pathology.

Influencia del sistema de salud de procedencia y otros factores en el resultado del reemplazo valvular mitral / Influence of the referring health care systems and other factors on the results of mitral valve replacement

Background: There is no consensus regarding which risk factors influence the outcome of mitral valve replacement. Aim: To study the effects ofthe referring health care system and other factors on the results of mitral replacement. Patients and Methods: We included 632 patients operated between 1990 and 2010 receiving the St Jude prosthesis. Patients were divided into three groups, group 1 composed by 180 patients coming from the Public System, group 2 composed by 182 patients coming from the University System and group 3 composed by 270 patients coming from the Private System. Results: Overall operative mortality was 4.3%. There was no difference between groups in mortality. Factors responsible for operative mortality were: emergency operation (Odds Patio (OR): 5.6 P < 0.01) and left ventricular function (according to ejection fraction) grade III to IV (OR: 2.5 p = 0.048). Actuarial survival rates at 1, 5, 10, 15 and 20 years were 95%, 87%, 76%, 61% and 41%, respectively. Risk factors for long-term mortality were diabetes (OR: 3.3 p < 0.01), left ventricular function grades III-IV (OR: 2.6 p < 0.01), New York Heart Association functional class III to PV (OR: 2.1 p < 0.005) and male sex (OR: 1.5 p < 0.032). Conclusions: Referring health care system and type of surgery do not constitute a risk factor for mitral replacement. Risk factors were: emergency surgery, ventricular function grades III-IV, diabetes, functional capacity class III-IV and male sex. Integration of public and private health care systems in a university hospital setting achieves excellent outcomes for complex pathology.

[Reducing the incidence of ventilator-associated pneumonia following heart surgery: 13-year experience of epidemiologic surveillance in a teaching hospital]. / Reducción de incidencia de neumonía asociada a ventilación mecánica post cirugía cardíaca: experiencia de 13 años de vigilancia epidemiológica en un hospital universitario.

OBJECTIVES: To report the results of 13 years worth of epidemiologic surveillance of ventilator-associated pneumonia (VAP) following heart surgery and the main interventions applied in order to reduce VAP incidence. METHODS: This is a retrospective and descriptive study of active epidemiologic surveillance of VAP. National diagnostic criteria were used. Interventions associated with a decrease in VAlP incidence in adults who underwent heart surgery are described. RESULTS: A significant and sustained reduction was observed in the rate of VAP; being 56.7 per 1,000 ventilator-days in 1998 vs 4.7 per 1,000 ventilator-days in 2010 (p < 0.001). The strongest reduction was observed following 2003 (34.4 to 14.8 per 1,000 ventilator-days in 2004, p < 0.001). The interventions with greatest impact were the implementation of an early-weaning protocol, the introduction of trained nurses to perform the mechanical ventilator equipment management and the routine use of alcohol-based hand rubs. CONCLUSION: Epidemiologic surveillance associated with the establishment of a multifactorial intervention program applied in collaboration with the attending team, have demonstrated a significant reduction of VAP incidence after heart surgery.

Reducción de incidencia de neumonía asociada a ventilación mecánica post cirugía cardíaca: experiencia de 13 años de vigilancia epidemiológica en un hospital universitario / Reducing the incidence of ventilator-associated pneumonia following heart surgery: 13-year experience of epidemiologic surveillance in a teaching hospital

Objectives: To report the results of 13 years worth of epidemiologic surveillance of ventilator-associated pneumonia (VAP) following heart surgery and the main interventions applied in order to reduce VAP incidence. Methods: This is a retrospective and descriptive study of active epidemiologic surveillance of VAP. National diagnostic criteria were used. Interventions associated with a decrease in VAlP incidence in adults who underwent heart surgery are described. Results: A significant and sustained reduction was observed in the rate of VAP; being 56.7 per 1,000 ventilator-days in 1998 vs 4.7 per 1,000 ventilator-days in 2010 (p < 0.001). The strongest reduction was observed following 2003 (34.4 to 14.8 per 1,000 ventilator-days in 2004, p < 0.001). The interventions with greatest impact were the implementation of an early-weaning protocol, the introduction of trained nurses to perform the mechanical ventilator equipment management and the routine use of alcohol-based hand rubs. Conclusion: Epidemiologic surveillance associated with the establishment of a multifactorial intervention program applied in collaboration with the attending team, have demonstrated a significant reduction of VAP incidence after heart surgery.

Objetivos: Comunicar los resultados de 13 años de vigilancia epidemiológica de neumonía asociada a ventilación mecánica (NAVM) post cirugía cardíaca y las principales intervenciones implementadas para reducir su incidencia. Metodología: Estudio retrospectivo, descriptivo, de vigilancia epidemiológica activa de NAVM utilizando los criterios del ]Ministerio de Salud (MINSAL) y de las intervenciones asociadas con una disminución de la tasa de NAVM en adultos operados de cirugía cardíaca. Resultados: Se observó una reducción significativa y sostenida de la tasa de NAVM, siendo 56,7 por 1.000 días de ventilación mecánica (VM) en 1998 vs 4,7 por 1.000 días de VM en 2010 (p < 0,001). La mayor reducción fue observada a partir de 2003 (desde 34,4 a 14,8 por 1.000 días de VM en 2004, p < 0,001). Las intervenciones con mayor impacto fueron la implementación de un protocolo de extubación precoz, la incorporación de enfermeras capacitadas en el manejo de los equipos de VM y el uso rutinario de alcohol gel. Conclusión: La vigilancia epidemiológica asociada a un programa de intervención multifactorial aplicado en conjunto con el equipo tratante permitió reducir significativamente la incidencia de NAVM post cirugía cardíaca.

Práctica transfusional en pacientes adultos sometidos a cirugía cardíaca con circulación extracorpórea: experiencia de la Pontificia Universidad Católica de Chile / Prediction of blood transfusion need in patients undergoing open heart surgery: the experience of Catholic University Hospital, Chile

Antecedentes: La cirugía cardíaca se asocia a un alto consumo de sangre homóloga. Si conocemos los factores quepredicen una mayor necesidad de transfusión, podremos implementar mejores estrategias de ahorro sanguíneo. Objetivo: Describir la práctica transfusional en pacientes adultos sometidos a cirugía con circulación extracorpórea (CEC) en la Pontificia Universidad Católica de Chile. Materiales y métodos: Se recolectaron en forma retrospectiva los datos de 194 pacientes adultos sometidos a cirugía cardíaca con CEC, entre octubre de 2003 y marzo de 2004. Se realizó una descripción de la práctica transfusional y un análisis de riesgo uni y multivariado. Resultados: El 61,8 por ciento de los pacientes se transfundieron durante la hospitalización. La transfusión intraoperatoria se relacionó con sangrado y la transfusión postoperatoria con la corrección de un hematocrito bajo. Los factores predictores de transfusión fueron cirugía de urgencia, tiempo prolongado de CEC, edad avanzada y un menor hematocrito al momento de ingresar a la unidad de cuidado postoperatorio. El hematocrito bajo al inicio de la cirugía, una menor temperatura durante CEC y un mayor sangrado en el postoperatorio predijeron el uso de más de dos unidades de glóbulos rojos (GR).Los pacientes que recibieron más de 2 unidades de GR presentaron en forma significativa mayor incidencia de neumonía, insuficiencia respiratoria y sepsis. Conclusiones: La transfusión sanguínea en cirugía cardíaca se relaciona directamente con la complejidad de los pacientes y los procedimientos. Las técnicas de ahorro de sangre deben dirigirse hacia la disminución del sangrado, la hemodilución y a estrictos criterios de transfusión intra y postoperatorios.

Background: Cardiac surgery is associated with frequent use of homologous blood. The knowledge of factors that influence the need for transfusion might help us implement strategies to avoid unnecessary blood administration. Objective: To describe the current transfusion practices in adults undergoing open cardiac surgery with extra corporeal circulation (ECC) at the Pontificia Universidad Católica of Chile Hospital. To identify factors that predict the use of transfusion. Methods: Data from 194 adult patients submitted to cardiac surgery with ECC between October 2003 and March 2004 were obtained retrospectively. Transfusional practices were identified. Uni and multivariate risk analysis was used to predict the need for transfusion.Results: 61,8 percent of patients were transfused during their hospital stay. Intraoperative transfusion was related to bleeding while post operative transfusion was performed to correct a low hematocrit value. Factors predicting transfusion were: emergency surgery, prolonged EEC time, older age and lower hematocrit value when entering the ICU. Preoperative hematocrit, lower temperature during ECC and post operative bleeding predicted the use of more than 2 red blood cell (RBC) packs. Patients receiving more than 2 RBC packs had a significantly higher incidence of pneumonia, sepsis and respiratory failure. Conclusion: Blood transfusion during cardiac surgery is directly related to complexity of procedures and severeness of patient illness. Blood saving techniques must be directed to reducing the amount of bleeding, allowing hemodilution and defining strict criteria for intra and post operative transfusions.

[Long-term results of repair versus replacement for degenerative mitral valve regurgitation]. / Resultados alejados de la reparación versus reemplazo en insuficiencia mitral degenerativa.

BACKGROUND: Mitral valve repair is considered better than mitral valve replacement for degenerative mitral regurgitation. AIM: To evaluate late clinical results of mitral valve repair as compared to mitral valve replacement in patients with degenerative mitral regurgitation. PATIENTS AND METHODS: All patients subjected to open heart surgery for degenerative mitral regurgitation between 1990 and 2002 were assessed for surgical mortality, late cardiac and overall mortality, reoperation, readmission to hospital, functional capacity and anticoagulant therapy. Eighty eight patients (48 males) had mitral valve repair and 28 (19 males) had mitral valve replacement (23 with a mechanical prosthesis). Mean age was 59.9 +/- 14.8 (SD) and 61.3 +/- 14.6 years, respectively. Sixty three percent of patients with repair and 50% of those with valve replacement were in functional class III or IV before surgery. RESULTS: Operative mortality was 2.3% for mitral valve repair and 3.6% for mitral valve replacement (NS). Also, there was no statistical difference in the need of reoperation during the follow-up period between both procedures (2.3% and 0%, respectively). Ninety four percent of the replacement patients but only 26% of the repair patients were in anticoagulant therapy at the end of the follow-up period (p < 0.001). Ten years survival rates were 82 +/- 6% for mitral valve repair and 54 +/- 11% for replacement. The corresponding cardiac related survival rates were 89 +/- 6% and 79 +/- 10%. At the end of follow-up, all surviving patients were in functional class I or II. Ten years freedom from cardiac event rates (death, cardiac related rehospitalization and reoperation) were 90 +/- 3% for mitral valve repair and 84 +/- 6% for replacement. CONCLUSION: Repair of the mitral valve offers a better overall survival and a better chance of freedom from cardiac events as well as need for anticoagulation 10 years after surgery.

[Valve repair surgery for incompetent bicuspid aortic valves]. / Ciruguía reparadora de la válvula aórtica bicúspide insuficiente.

BACKGROUND: Surgical valve repair is a good alternative for correction of incompetent bicuspid aortic valve. AIM: To report the early and late surgical, clinical and ecochardiographic results of surgical repair of incompetent bicuspid aortic valves. PATIENTS AND METHODS: Retrospective review of medical records of 18 patients aged 19 to 61 years, with incompetent bicuspid aortic valve in whom a valve repair was performed. Four patients had infectious endocarditis and 17 were in functional class I or II. Follow up ranged from 3 to 113 months after surgery. RESULTS: A triangular resection of the prolapsing larger cusp, which included the middle raphe, was performed in 17 cases; in 13 of these, a complementary subcommisural annuloplasty was performed. In the remaining case, with a perforation of the non-coronary cusp, a pericardial patch was implanted; this procedure was also performed in 2 other cases. In 3 cases large vegetations were removed. Postoperative transesophageal echocardiography showed no regurgitation in 11 patients (62%) and mild regurgitation in 7 (38%). There was no operative morbidity or mortality. There were no deaths during the follow-up period. In 3 patients (17%) the aortic valve was replaced with a mechanical prosthesis, 8 to 108 months after the first operation. Reoperation was not needed in 93%+/-6,4% at 1 year and 85%+/-9,5% at 5 years, these patients were all in functional class I at the end of the follow-up period. 60% had no aortic regurgitation, 20% had mild and 20% moderate aortic regurgitation on echocardiographic examination. A significant reduction of the diastolic diameter of the left ventricle was observed, but there were no significant changes in systolic diameter or shortening fraction. CONCLUSIONS: Surgical repair of incompetent bicuspid aortic valves has low operative morbidity and mortality and has a low risk of reoperation.

[Valve repair surgery in infectious endocarditis]. / Cirugía valvular reparadora en endocarditis infecciosa.

BACKGROUND: Valve replacement has been the treatment of choice for patients with valvular complications of infectious endocarditis (IE). However, excellent results with valve repair allowed it to become a new therapeutic alternative for these patients. AIM: To evaluate the results of valve repair in patients with valvular complications of IE. PATIENTS AND METHODS: From January 1991 to December 2000, 14 patients with valvular complications of IE underwent valve repair. Mean age was 37.9 +/- 14.9. RESULTS: New York Heart Association (NYHA) class was 2.8 +/- 0.9. IE was located in the aortic in 6 (42%), in the mitral valve in 4 (29%) and in both valves in 4 cases (29%). Surgical indication was hemodynamic in 50% of the cases, echocardiographic in 29% and septic in 21%. Five aortic valves were bicuspid, 3 mitral valves were myxomatous and the rest were normal. The most common septic lesions were vegetations and leaflet perforations. A total of 23 aortic and 21 mitral valve repair procedures were performed. There were no deaths. Only 1 patient had a surgical complication (renal failure and prolonged mechanical ventilation). Follow-up was 100% complete. There was not late mortality. One patient with bone marrow aplasia required reoperation for a new episode of IE 19 months later. At the end of the follow-up NYHA class was 1.3 +/- 0.6 and echocardiography showed a mild or absence of valve regurgitation in most patients. CONCLUSIONS: Valve repair surgery in IE has good results, with advantages over valve replacement.

[Immediate results of palliative surgery for different forms of univentricular heart using the Norwood procedure]. / Cirugía paliativa mediante operación de Norwood en distintas formas de corazón univentricular: resultados quirúrgicos inmediatos.

BACKGROUND: Norwood procedure is used as the first stage in the palliative treatment of the hypoplastic heart syndrome and can be used, with some technical modifications, in other forms of univentricular heart with aortic stenosis or hypoplasia. These patients have a high mortality (50%), derived from the procedure itself and from their abnormal physiological status. AIM: To report our experience with the Norwood procedure. PATIENTS AND METHODS: Retrospective analysis of all patients subjected to the Norwood procedure between February, 2000 and June 2003. RESULTS: Thirteen patients (9 females, age range 5-60 days and median weight of 3.3 kg) were operated. Eight had hypoplastic heart syndrome and five had a single ventricle with aortic arch hypoplasia. The diagnosis was done in utero in eight patients. All technical variations, according to the disposition and anatomy of the great vessels, are described. Cardiac arrest with profound hypothermia was used in all and regional cerebral perfusion was used in nine. Three patients died in the perioperative period and three died in the follow up (two, four and 10 months after the procedure). Gleen and Fontan procedures were completed in five and one patients, respectively. CONCLUSIONS: Our results with the Norwood procedure are similar to other series. There is an important mortality in the immediate operative period and prior to the Glenn procedure.

[Axillary artery cannulation for extracorporeal circulation]. / Canulación de arteria axilar para circulación extracorpórea.

BACKGROUND: When the ascending aorta and the femoral artery cannot be used for extracorporeal circulation, an emerging alternative is the use of axillary artery. AIM: To report the experience using the axillary artery for extracorporeal circulation. PATIENTS AND METHODS: Between November 1998 and May 2002, 22 patients (14 male) were operated with extracorporeal circulation, cannulating the axillary artery. Briefly, an incision is made below the middle third of the clavicle and a cut is made on major pectoris muscle. Minor pectoris muscle is retracted and axillary artery is exposed. It is cannulated directly or with the aid of a prosthesis. RESULTS: Right axillary artery was used in 21 patients and in 20 it was cannulated with the aid of a prosthesis. Mean flow was 4.5 +/- 0.6 l/min. The most common indications were aortic dissection or aneurysms. The most common procedures done, were ascending aorta replacement in 8 cases and replacement of ascending aorta and aortic arch in 5. Thirty five percent of operations were emergencies and 32% were reoperations. In 15 patients (68%), a circulatory arrest was done. Of these, retrograde brain perfusion was used in 9, antegrade brain perfusion through the same axillary artery was used in 2 and mixed perfusion was used in 2. One patient had a complication related to the axillary cannulation. None had cerebrovascular accidents or thromboembolic complications. Two patients died in the postoperative period. Patients were followed up to 42 months after the procedure and no secondary complications of the cannulation were detected. CONCLUSIONS: When the ascending aorta and the femoral artery cannot be used, axillary artery is a good alternative for extracorporeal circulation.

[A 36 years experience with implantable pacemakers. A historical analysis]. / Experiencia de 36 años con marcapasos implantables. Un análisis histórico.

BACKGROUND: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. AIM: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. MATERIAL AND METHODS: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificación de Chile (Chilean Civil and Identification Registry). RESULTS: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74% from 1988 to 1998. Complication rate was 42% in the 1963-1976 study period, it decreased to 10.6% in the 1977-1987 study period, and to 5.6% by 1988-1998. Only two patients died during surgery in the study period (0.08%). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52% at ten years, 33% at 15 years, and 21% at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. CONCLUSIONS: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures.

[Surgery for mitral valve insufficiency]. / Cirugía de la insuficiencia mitral isquémica.

BACKGROUND: Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, notwithstanding a relatively high mortality rate. OBJECTIVES: To evaluate the results of mitral valve replacement or repair in patients with IMR. PATIENTS AND METHODS: Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8% of surgical procedures on the mitral valve. RESULTS: Mean age was 67 +/- 9 years. Surgery was performed urgently in 19 patients (66.5%). NYHA functional class was 3.4 +/- 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83%) had concomitant myocardial revascularization. Overall surgical mortality was 24%; 26% for mitral replacement and 13% for mitral valve repair (p = 0.215). On follow up of 26 +/- 33 months, one year survival was 76 +/- 0.8% and 5 years survival was 59 +/- 12%. Excluding in hospital mortality, survival was 100% at one year and 78 +/- 14% at 5 years. Functional class improved in all survivors, to 1.4 +/- 0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58%, 1+ MR in 17% and 2+ MR in 25%. CONCLUSION: In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease.

[Fontan procedure: early and mid-term results with total cavopulmonary anastomosis]. / Operación de Fontan: resultados inmediatos y a mediano plazo con anastomosis cavopulmonar total.

BACKGROUND: During the last five years, 65 patients with univentricular heart have been treated surgically in our institution, according to a protocol of staged operations that have been previously reported. AIM: To evaluate the early and mid-term outcome of those patients that have completed their staging protocol by means of a Fontan procedure. PATIENTS AND METHODS: Between April 1996 and June 2001, 23 patients (age 16 to 223 months) underwent a Fontan procedure, 15 with an intracardiac lateral tunnel technique and 8 with an extracardiac conduit. A retrospective review of their clinical, surgical, echocardiographic, angiographic and hemodynamic data was performed, trying to identify risk factors for both mortality and functional capacity (FC). Follow up was complete in all survivors. RESULTS: Three patients died early after surgery (13.04%). Excessive pulmonary blood flow was a risk factor for early death (p = 0.03). One patient died at 14 months. Follow up was 29.9 months (1-63). For those who survived the operation, five years survival was 93.3%. The majority of patients are in FC I or II, with no related risk factors. CONCLUSIONS: Our current results are comparable with those of larger series. Patients reach good FC and mid-term survival, irrespective of type of single ventricle or the surgical strategy.

Tratamiento quirúrgico del síndrome de Wolff-Parkinson-White / Surgical treatment of Wolff-Parkinson-White syndrome

La sección quirúrgica de los haces paraespecíficos ha demostrado ser un tratamiento eficaz para las taquicardias del síndrome de Wolff-Parkinson-White. Comunicamos nuestra experiencia con el tratamiento quirúrgico de 9 pacientes, 7 mujeres y 2 hombres, con edad promedio de 30 años. Siete pacientes tuvieron haces laterales izquierdos, 2 posteroseptales y 1 anteroseptal (1 pt con 2 haces) diagnosticados mediante estudio electrofisiológico preoperatório. La intervención se realizó con circulación extracorpórea en normotermia para los haces derechos y con hipotemia sistémica y cardioplejía en los haces izquierdos. El mapeo intraoperatorio permitió la exacta ubicación de los haces responsables de la preexitación. No hubo mortalidad ni morbilidad perioperatoria. En el 100% de los pacientes se observó eliminación de la preexitación en el estudio electrofisiológico intra y postoperatorio antes del alta. Todos los pacientes mantuvieron ritmo sinusal. En el seguimiento alejado (promedio 7 meses), todos los pacientes están en buenas condiciones, sin medicamentos antiarrítmicos y libres de nuevas crisis de taquicardia, excepto 1 pt en quien reapareció la preexitación. Concluimos que el tratamiento quirúrgico tiene un riesgo bajo y éxito del 90% en la sección definitiva del haz paraespecífico. Postulamos que la cirugía constituye un excelente alternativa de tratamiento para el síndrome de Wolff-Parkinson-White

Hidatidosis miocárdica: descripción de un caso y revisión de la literatura / Miocardial hydatidosis: report of a case and review of the literature

La Hidatidosis Cardíaca es una entidad clínica poco frecuente, con una incidencia menor al 3% de todos los casos de Hidatidosis humana. Su diagnóstico es de vital importancia, pudiendo realizarse por medio de distintos métodos no invasivos, como Radiografía de Tórax. Electrocardiograma, Ecocardiograma Bidimensional y Scanner Torácico, permitiendo la cirugía precoz, antes que se presenten las complicaciones, lo que hace que la cirugía sea curativa. El propósito de esta publicación es presentar el caso de una paciente portadora de quiste hidatídico ventricular isquierdo, tratado con cirugía, y revisar la literatura pertinente