Resultados alejados de la cirugía reconstructora de la insuficiencia mitral / Long term results of reconstructive surgery for mitral insufficiency

Background: Surgical repair is the procedure of choice for mitral insufficiency since it preserves better left ventricular structure and function. Aim: To assess the long term clinical and echocardiographic results of mitral valve reconstructive surgery. Material and methods: A review of clinical and echocardiographic data of 68 patients (34 male, age range 17 to 82 years), subjected to surgical mitral valve repair between december 1991 and march 1998. Preoperative functional capacity of these patients was 2.96 ñ 0.7. Surgical repair was assessed using transesophagic echocardiography in all subjects. Results: The etiology of mitral insufficiency was degenerative in 43 patients, rheumatic in 10, infectious in 6, ischemic in 5 and miscellaneous in 4. The most frequent pathological findings were dilatation of the mitral ring in 42 percent of patients, chordae tendinae rupture in 32 percent and enlargement in 24 percent. A mitral anuloplasty was done in 90 percent of patients, a cuadrilateral resection of posterior leaflet in 52 percent and chordae tendinae transference in 12 percent. An additional surgical procedure was done in 34 percent of subjects. Three patients died during hospitalization (4.4 percent). During the follow up of 36.5 ñ 22.3 months, five patients died and one required a mitral valve replacement. The actuarial survival probability was 95.3 ñ 2.6 percent at one year and 83.5 ñ 6.5 percent at five years. The reoperation free survival was 100 percent at one year and 97.4 ñ 2.5 percent at five years. At the end of follow up the functional capacity improved to 1.25 ñ 0.4. echocardiography showed absence of mitral insufficiency in 48.4 percent of patients, minimal, mild and moderate insufficiency in 35.5, 14.5 and 1.6 percent of patients respectively. Conclusions: Surgical valve reconstruction in mitral insufficiency has satisfactory long term results and should be the procedure of choice for eligible patients

Aspectos morfo-funcionales de arterias y venas mamarias usadas en revascularización cardíaca / Morphologic and functional aspects of mammary arteries and veins used for myocardial revascularization surgery

Los vasos sanguíneos están inervados por el sistema nervioso simpático autonómico. La fisiología y neuroquímica de los nervios perivasculares humanos ha sido poco estudiada. Con el propósito de contribuir a las investigaciones sobre la fisiología de la co-transmisión simpática humana, esta investigación se concentró en: i) estudiar el contenido de los neurotransmisores simpáticos, noradrenalina (NA) y neuropéptido y (NPY) en vasos de arteria y vena mamaria interna humana; ii) detectar mediante técnicas inmunohistoquímicas la presencia de los nervios simpáticos perivasculares de estos vasos; iii) caracterizar la reactividad vascular de la arteria mamaria interna, como un modelo usado en implantes de revascularización cardíaca. Se estudió además, la vena mamaria derivada de la misma biopsia. La arteria y vena mamaria contienen 50 veces más NA que NPY, el contenido de NA y NPY en la arteria y en la vena es muy similar. La detección inmunohistoquímica de los nervios simpáticos demuestra que éstos se localizan entre las capas musculares de los vasos. La estimulación de los filetes nerviosos perivasculares produce respuestas vasomotoras sensibles a tetrodotoxina y guanetidina, lo que es consistente con la naturaleza simpática de la respuesta, confirmando que parte de los nervios perivasculares son simpáticos. Los músculos lisos se estimulan por NA y por ATP, que sólo no contrae, facilita las respuestas vasomotoras de la NA. Estos resultados permiten concluir que en la arteria y la vena mamaria interna humana NA, ATP y NPY cooperan en la respuesta vasomotora, evidenciando la co-transmisión simpática en humanos

Cirugía coronaria mínimamente invasiva / Minimally invasive coronary artery surgery

Background: There is a growing interest to perform a left internal mammary artery (LIMA) graft to the left anterior descending coronary artery (LAD) on a beating heart through a minimally invasive access to the chest cavity. Aim: To report the experience with minimally invasive coronary artery surgery. Patients and methods: Analysis of 11 patients aged 48 to 79 years old with single vessel disease that, between 1996 and 1997, had a LIMA graft to the LAD performed through a minimally invasive left anterior mediastinotomy, without cardiopulmonary bypass. A 6 to 10 cm left parasternal incision was done. The LIMA to the LAD anastomosis was done after pharmacological heart rate and blood pressure control and a period of ischemic pre conditioning. Graft patency was confirmed intraoperatively by standard Doppler techniques. Patients were followed for a mean of 11.6 months /7-15 months). Results: All patients were extubated in the operating room and transferred out of the intensive care unit on the next morning. Seven patients were discharged on the third postoperative day. Duplex scanning confirmed graft patency in all patients before discharge; in two patients, it was confirmed additionally by arteriography. There was no hospital mortality, no perioperative myocardial infarction and no bleeding problems. After follow up, ten patients were free of angina, in functional class I and pleased with the surgical and cosmetic results. One patient developed atypical angina on the seventh postoperative month and a selective arteriography confirmed stenosis of the anastomosis. A successful angioplasty of the original LAD lesion was carried out. Conclusions: A minimally invasive left anterior mediastinotomy is a good surgical access to perform a successful LIMA to LAD graft without cardiopulmonary bypass, allowing a shorter hospital stay and earlier postoperative recovery. However, a larger experience and a longer follow up is required to define its role in the treatment of coronary artery disease

Valor pronóstico de tres clasificaciones utilizadas en cáncer colorrectal con compromiso ganglionar / Prognostic value of 3 classifications uses in colorectal cancer with ganglionar compromise

Existen varias clasificaciones para la etapificación del cáncer colorrectal que tiene valor pronóstico, luego de resecciones con intención curativa. La más utilizada y punto de referencia para las demás, es la de Dukes. En ésta se incluye a todos los pacientes con compromiso ganglionar habría subgrupos de enfermos con distinto pronóstico. Para analizar el valor actual de la clasificación Dukes, se revisaron entre los años 1975 y 1985. En forma paralela un grupo de patológos revisó el material histológico de estos pacientes seleccionando a aquellos cob metástasis ganglionares. De esta forma se constituyó un grupo de 94 enfermos quienes fueron etapificados utilizando 3 clasificaciones actualmente en uso en cáncer colorrectal (Dukes C, Astler y Coller C1, C2 y GITSG C1, C2). El promedio de ganglios examinados en las piezas operatorias y el promedio de metástasis ganglionares por pieza operatoria fue 12,6 y 2,9 respectivamente. Se observó una relación entre las metástasis ganglionares y el grado de invasión de tumor en la pared, ya que en un 89 por ciento de los enfermos el tumor comprometía todas las túnicas del colon. En el análisis de sobrevida a 5 años se debe destacar la presencia de 3 poblaciones de enfermos con pronósticos muy diferentes: Astler y Coller C1= 85 por ciento, Dukes C= 47 por ciento y GITSG C2= 30 por ciento. Se concluye que el grupo de pacientes con metástasis ganglionares (Dukes) es muy amplio incluyendo subgrupos de pacientes con pronóstico distinto

Cirugía de revascularización miocárdica en los primeros 15 días de evolución del infarto / Miocardial revascularization surgery in the first 15 days of infarction evolution

Revascularization significantly improves early and late prognosis in acute myocardial infarction and has prompted substantial changes in therapeutic strategies. We report 140 patients aged 60.3 years old (123 male) operated within 15 days of sustaining an acute myocardial infarction, between january 1984 and december 1989. Coronary angiogram showed single vessel disease single vessel disease in 8 (6 percent), double vessel disease in 32 (23 percent), triple vessel disease in 85 (61 percent) and left main vessel disease in 13 (9 percent). Indications for surgery were ponstinfarction angina in 92 patients (66 percent), multiple severe coronary stenosis in 18 (13 percent), infarction of less than six hours from onset in 16 (11 percent), acute angioplasty failure in 7 (5 percent) and cardiogenic shock in 7 (5 percent). Thirty one patients were operated during the initial 24 h of infarction (16 with less than 6 h) 14 between the second and third day and 95 between the fourth and fifteenth day. Overall mortality was 4.3 percent (6/140). Among patients with failed angioplasty and cardiogenic shock, mortality was 23 percent (7/140), among patients with postinfarction angina this figure was 2.1 percent (2/92). Five years actuarial survival was 95 percent and the actuarial probability of being free of acute myocardial infarction, angioplasty or reoperation at five years was 99 and 100 percent respectively. It is concluded that early surgical revascularization in acute myocardial infarction is safe and has excellent long term results

Traslocación bacteriana en un modelo de autotrasplante de intestino delgado en perros / Bacterial translocation in a small intestine auto transplantation model in dogs

Sepsis is the commonest complication of small bowel transplantation. These infections are presumibly caused by bacterial translocation, due to splachnic ischemia. To study bacterial translocation in the inmediate postoperative period after small bowel transplantation in dogs and to relate it to splanchnic ischemia. Three groups of dogs were studied. In group A (n=6) spontaneous episodes of splanchnic schemia were monitored in the first 18 hrs of the postoperative period. In group B (n=5) a 60 min ischemia was induced by superior mesenteric artery occlusion, 2 hours after small bowel transplantation. In group C (n=5) a 60 min ischemia was induced by occlusion of mesenteric vein, 2 hrs after transplantation. Bacterial translocation was assessed through bacterial cultures from the mesenteric vein and splanchnic ischemia with intramucosal pH measurement (a pH<7.2 was considered indicative of ischemia). 28 of 83 cultures were positive, specially for Gram negative bacilli. The incidence of positive cultures was 14 percent for group A, 17 percent for group B and 79 percent for group C (p<0.01 cpmpared to groups A and b). The higher incidence of bacterial translocation occurred during the first 2 hours after transplantation, when the lower intramucosal pH recording were obtained. The percentage of positive cultures was 39 percent during periods of ischemia, compared to 24 percent during periods without ischemia (p=NS). Bacterial translocation occurs during the first 2 hours after intestinal transplantation in concomitance with the lower intramucosal pH readings

Resultados del tratamiento quirúrgico y seguimiento en las herniorrafias con prótesis / Results of surgical treatment and follow up of herniorraphy with prosthesis

Se revisó las fichas clínicas de todos los pacientes a quienes se les practicó una herniorrafia con prótesis (HCP), en el período enero de 1975 y diciembre de 1988. En este período se operaron 87 pacientes, 54 mujeres y 33 hombres, la edad promedio fue 58 años. No se obtuvo información de seguimiento en 8 pacientes, quedando constituido nuestro grupo por 79 enfermos. Fueron controlados personalmente por los autores 70 pacientes (88,6%) y en los 9 restantes, los datos fueron obtenidos por entrevista telefónica. El promedio de seguimiento fue 50 meses (rango 6-168 meses). Treinta enfermos (37,9%) habían sido sometidos al menos a una herniorrafia previa antes de la HCP. No hubo mortalidad operatoria en esta serie y siete pacientes (9%) presentaron una o más complicaciones. En veinte pacientes recidivó la hernia (25%). Es importante mencionar que más de un tercio de las recidivas se presentó despues de los 36 meses de seguimiento. No hubo diferencias significativas en el porcentaje de recidivas según los distintos tipos de prótesis, localización de la malla, número de herniorrafias previas, tipos de sutura y obesidad del paciente. Sólo en el grupo de pacientes con limitación crónica del flujo aéreo, constipación y uropatía obstructiva hubo un mayor porcentaje de recidivas (p < 0,05)