Cuándo y cómo realizar una biopsia de las lesiones cutáneas frecuentes: lo que el cirujano debe saber / How and when to perform a skin biopsy of a pigmented lesion: what the surgeon need to know

At present times, general surgeons are continuously faced to evaluate patients with pigmented lesions. Thus, is very important that surgeons acquire adequate knowledge not only to distinguish between suspicious lesion and non suspicious lesion, but also to correctly assess when and how to perform a skin biopsy. The early detection of melanoma and non melanoma skin cancer is one of the most important factors to achieve a better prognosis. The main objective of this article is to provide surgeons some tips and pitfalls to help accurate the evaluation and diagnosis of pigmented lesions. The authors also want to stress out the importance of the team work between surgeons and dermatologist, due that is well documented that multidisciplinary approach to skin cancer raises the possibilities of early diagnosis, adequate treatment and better results for patients with skin cancer.

En la actualidad, el cirujano continuamente se ve enfrentado a evaluar distintos tipos de lesiones cutáneas en los pacientes, por lo que debe tener conocimientos de las características que hacen que una lesión sea sospechosa o no, para evaluar correctamente cuándo y cómo realizar una biopsia de una lesión cutánea. El diagnóstico precoz, tanto del melanoma como del cáncer de piel no melanoma, ha demostrado ser clave para mejorar el pronóstico de nuestros pacientes. Este artículo pretende entregar algunas claves para afinar la evaluación y diagnóstico de las lesiones pigmentadas. Es muy importante también, recalcar la importancia del trabajo conjunto de los cirujanos con los dermatólogos, ya que la evaluación y manejo multidisciplinario mejora sustancialmente el diagnóstico, tratamiento y resultados de los pacientes con cáncer de piel.

[Surgical treatment of renal hyperparathyroidism. Experience in 71 patients]. / Tratamiento quirúrgico del hiperparatiroidismo asociado a insuficiencia renal crónica.

BACKGROUND: Surgery is an effective method for the management of renal hyperparathyroidism. AIM: To report the clinical presentation and results of surgical treatment of renal hyperparathyroidism. MATERIAL AND METHODS: Retrospective analysis of 58 patients aged 46 ± 11 years with secondary hyperparathyroidism (HPT2) and 13 patients aged 53 ± 11 years with tertiary hyperparathyroidism (HPT3), operated at a clinical hospital. RESULTS: In 55 cases (77.4%) the indications for surgery were complications of excess parathyroid hormone (PTH) and in 16 patients (22.6%) a failure of medical treatment. Total parathyroidectomy with intraoperative measurement of PTH (PTHop) plus a forearm parathyroid autograft was performed in 54 (93.1%) patients with HPT2 and in all patients with HPT3. PTHop decreased ≥ 75% in 51 patients (88%) with HPT2 and in 9 patients (69.2%) with HPT3, respectively. Cure of the disease was achieved in 52 (89.7%) and 11 (84.6%) patients with HPT2 and 3, respectively. Median follow-up was 41 months. Five (9.6%) patients with HPT2 and two patients (18.2%) with HPT3 had a recurrence of the disease. CONCLUSIONS: In patients with renal hyperparathyroidism, the primary indication for surgery was the presence of complications of PTH excess. A drop in PTHop ≥ 75% from baseline predicts healing in 98% and 100% of cases with secondary or tertiary HPT respectively. Surgery was a safe and effective treatment in both groups.

Tratamiento quirúrgico del hiperparatiroidismo asociado a insuficiencia renal crónica: Experience in 71 patients / Surgical treatment of renal hyperparathyroidism

Background: Surgery is an effective method for the management of renal hyperparathyroidism. Aim: To report the clinical presentation and results of surgical treatment of renal hyperparathyroidism. Material and Methods: Retrospective analysis of 58 patients aged 46 ± 11 years with secondary hyperparathyroidism (HPT2) and 13 patients aged 53 ± 11 years with tertiary hyperparathyroidism (HPT3), operated at a clinical hospital. Results: In 55 cases (77.4%) the indications for surgery were complications of excess parathyroid hormone (PTH) and in 16 patients (22.6%) a failure of medical treatment. Total parathyroidectomy with intraoperative measurement of PTH (PTHop) plus a forearm parathyroid autograft was performed in 54 (93.1%) patients with HPT2 and in all patients with HPT3. PTHop decreased ≥ 75% in 51 patients (88%) with HPT2 and in 9 patients (69.2%) with HPT3, respectively. Cure of the disease was achieved in 52 (89.7%) and 11 (84.6%) patients with HPT2 and 3, respectively. Median follow-up was 41 months. Five (9.6%) patients with HPT2 and two patients (18.2%) with HPT3 had a recurrence of the disease. Conclusions: In patients with renal hyperparathyroidism, the primary indication for surgery was the presence of complications of PTH excess. A drop in PTHop ≥ 75% from baseline predicts healing in 98% and 100% of cases with secondary or tertiary HPT respectively. Surgery was a safe and effective treatment in both groups.

Hiperparatiroidismo primario: manejo quirúrgico / Primary hyperparathyroidism: surgical treatment

Background: Primary hyperparathyroidism (HPTP) is the most common cause of hypercalcaemia in the ambulatory setting. This condition affects between 0.1 -2 percent of the population. Surgery is the only curative treatment. Objective: The aim of the study is to present our 10-year surgical experience. Methods: Analytical-descriptive study. We included all patients diagnosed with HPTP treated with surgery in our hospital between June 2003 and June 2013. Results: 173 patients underwent surgery for HPTP. The mean age was 57.5 +/- 13.5 years. Asymptomatic in 98 cases (56.6 percent). Resection the abnormal parathyroid glands was performed in all cases with intraoperative PTH monitoring. In 167 patients (96.5 percent) intraoperative PTH declined ≥ 50 percent. The median follow-up was 61 months (1-117 months). Cure was achieved in 169 patients (97.7 percent). Four cases (2.3 percent) had recurrence. Conclusions: Surgery is effective and safe for the treatment of HPTP. A decline in intraoperative PTH > 50 percent predicts cure in 97.7 percent of cases.

Introducción: El hiperparatiroidismo primario (HPTP), es una entidad frecuente que afecta entre el 0,1 y 2 por ciento de la población. La cirugía es el único tratamiento curativo. Objetivo: Evaluar la eficacia y riesgos del tratamiento quirúrgico del HPTP. Material y Métodos: Estudio analítico-descriptivo. Se incluyó a todos los pacientes con diagnóstico de HPTP referidos para cirugía al Hospital Clínico de la Pontificia Universidad Católica de Chile entre junio de 2003 y junio de 2013. Resultados: 173 pacientes fueron operados en nuestra institución por HPTP. El promedio de edad de los pacientes fue de 57,5 +/- 13,5 años. La forma de presentación fue asintomática en 98 casos (56,6 por ciento) y sintomática en 75 casos (43,4 por ciento). Todos los pacientes fueron tratados con resección de la o las glándulas hiperfuncionantes con medición de PTH intraoperatoria. En 167 pacientes (96,5 por ciento) se logró caída de PTH intraoperatoria > 50 por ciento. Catorce pacientes (8,1 por ciento) presentaron complicaciones post operatorias. La mediana de hospitalización fue de 2 días (1 a 23 días). La mediana de seguimiento fue de 61 meses (6 a 117 meses). Se logró curación en 169 pacientes (97,7 por ciento). Cuatro casos (2,3 por ciento) presentaron recidiva. Conclusiones: La cirugía es eficaz y segura para el tratamiento del hiperparatiroidismo primario. Una caída de PTH intraoperatoria > 50 por ciento del valor basal predice curación en 97,7 por ciento de los casos.

Cáncer medular de tiroides: Experiencia quirúrgica en 10 años / Medullary thyroid cancer: Review of 28 patients

Background: Medullary thyroid cancer (MTC) represents approximately 5% of all thyroid cancers. Surgery is the only curative treatment, which includes total thyroidectomy and in most cases, neck dissection. Aim: To report our 10-year experience with surgical treatment of MTC. Material and Methods: Review of medical records and pathology reports of a university hospital. We retrieved data from 28 patients aged 47.2 ± 16 years (21 women) operated for a MTC treated between June 2002 and June 2012. Results: In 20 patients, MTC was diagnosed in the preoperative period. Total thyroidectomy was performed in all cases and included a neck dissection in 24 patients. Median follow-up was 48 (2-120) months. Twenty-five patients (89.2%) achieved complete remission of the disease and three had disease recurrence. There were no deaths during the follow up. Conclusions: The diagnosis of MTC is mainly based on cytology. Total thyroidectomy with neck dissection is the treatment of choice. An early-stage diagnosis is associated with low rates of recurrence and absence of mortality.

[Medullary thyroid cancer: review of 28 patients]. / Cáncer medular de tiroides: experiencia quirúrgica en 10 años.

BACKGROUND: Medullary thyroid cancer (MTC) represents approximately 5% of all thyroid cancers. Surgery is the only curative treatment, which includes total thyroidectomy and in most cases, neck dissection. AIM: To report our 10-year experience with surgical treatment of MTC. MATERIAL AND METHODS: Review of medical records and pathology reports of a university hospital. We retrieved data from 28 patients aged 47.2 ± 16 years (21 women) operated for a MTC treated between June 2002 and June 2012. RESULTS: In 20 patients, MTC was diagnosed in the preoperative period. Total thyroidectomy was performed in all cases and included a neck dissection in 24 patients. Median follow-up was 48 (2-120) months. Twenty-five patients (89.2%) achieved complete remission of the disease and three had disease recurrence. There were no deaths during the follow up. CONCLUSIONS: The diagnosis of MTC is mainly based on cytology. Total thyroidectomy with neck dissection is the treatment of choice. An early-stage diagnosis is associated with low rates of recurrence and absence of mortality.

Hallazgos anatomopatológicos definitivos en pacientes tiroidectomizados con diagnóstico preoperatorio de neoplasia folicular / Definitive anatomopathological findings in thyroidectomized patients with preoperative diagnosis of follicular neoplasm

Background: The finding of follicular neoplasm, using a FNAP, is an indication for partial or total thyroidectomy, to obtain the definitive malignant or benign histology. Frequently, it is possible to identify significant additional histological diagnosis. Aim: To obtain the definitive histological findings in patients with follicular neoplasm by FNAP. Patients and Method: Transversal analysis of 133 patients that underwent to total thyroidectomy between 2003 and 2009, that filled de requirements for adequate histological assessment. Results: In 33.1 percent of the treated patients the final diagnosis was indeed a follicular neoplasm (adenoma in 26.3 percent and cancer in 6.8 percent). In the 51.9 percent the finding was follicular colloidal hyperplasia and other thyroid cancer in 8.3 percent. The total malignant prevalence in the whole gland was 29.3 percent. Conclusions: The thyroidec-tomy is the treatment of choice and the final diagnostic procedure for these patients. The histological findings of cancer different from follicular not only in the punctioned nodule are a secondary and an additional argument for reinforcing the surgical indication.

Introducción: El hallazgo de una neoplasia folicular por PAAF, obliga a realizar una tiroidectomía parcial o total, para definir la naturaleza maligna o benigna definitiva de la lesión tiroidea. Junto a este diagnóstico preoperatorio se identifican finalmente con alta frecuencia lesiones histológicas adicionales. Objetivo: Conocer y describir los hallazgos anatomopatológicos definitivos que se encuentran en tiroidectomías por neoplasias foliculares diagnosticadas por PAAF. Materiales y Métodos: Revisión transversal de las biopsias definitivas de 133 pacientes sometidos a tiroidectomía total entre 2003 y 2009, que cumplieron los requisitos establecidos para evaluar la histología definitiva del nódulo puncionado y de la glándula tiroides completa. Resultados: En el 33,1 por ciento de los pacientes el diagnóstico definitivo del nódulo puncionado fue efectivamente una neoplasia folicular (adenoma en el 26,3 por ciento y cáncer en el 6,8 por ciento). El 51,9 por ciento correspondió a hiperplasia folicular y el 8,3 por ciento otro cáncer. La prevalencia de malignidad final en la glándula completa fue de un 29,3 por ciento. Conclusiones: Siendo la indicación de tiroidectomía en estos pacientes un tratamiento y procedimiento diagnóstico aceptado y necesario, se concluye que la alta prevalencia de lesiones malignas (29,3 por ciento) tanto en el nódulo puncionado como, adicionalmente, en el resto de la glándula, reforzaría la necesidad de este tratamiento quirúrgico.

Incidencia de granulomas en el lecho tiroideo con el uso de bisturí ultrasónico en pacientes sometidos a tiroidectomía total por cáncer / Postoperative thyroid bed granuloma incidence using ultrasonic knife in total thyroidectomy in cancer patients

Background: The postoperative thyroid bed granuloma incidence is high and it is an adittional difficulty for the ultrasound differential diagnosis of eventual local cancer recurrence. The ultrasonic knife utilization eventually can reduce the incidence of these granuloma when is compare with other traditional ligatures methods. Objective: to evaluate the postoperative thyroid bed granuloma incidence with the ultrasonic knife utilization, detected by ultrasound. Methods: retrospective study of 57 evaluable thyroidectomy performed for cancer between March and September 2010. In 46 patients were used traditional ligatures (silk or linen) and in 11, ultrasonic knife. Results: of the 57 patient included, 47 were females. The age average was 44 years old. Postoperative thyroid bed granuloma incidence was 36.3 percent (CI95 percent, 7.9 percent-64.7 percent) in the group where ultrasonic knife was used and 36.9 percent (IC95 percent, 23.0 percent-50.9 percent) in which traditional ligatures were used. No statistical difference was found (p = 0.974). Conclusions: The ultrasonic knife utilization had not reduced the postoperative thyroid bed granuloma incidence, when was compared with conventional ligatures. In this sense, this device is probably unable to add benefits for the differential diagnosis of thyroid cancer local recurrence.

Introducción: La incidencia de granulomas postoperatorios en el lecho tiroideo es alta y dificulta el diagnóstico diferencial ecográfico de posibles recidivas locales en cáncer. La utilización de bisturí ultrasónico disminuiría la incidencia de estos granulomas en comparación con métodos de sutura y hemostasia tradicionales con ligaduras. Objetivo: Evaluar si el uso de bisturí ultrasónico disminuye la incidencia de granulomas postoperatorios en el lecho tiroideo, que se detectan ecográficamente. Métodos: Retrospectivamente se revisaron los hallazgos ecográficos postoperatorios de 57 pacientes evaluables con cáncer de tiroides operados entre marzo y septiembre de 2010. En 46 pacientes se utilizó ligaduras (lino o seda) y en 11, bisturí ultrasónico. Resultados: De los 57 pacientes, 47 fueron mujeres. La edad promedio fue 44 años. La incidencia de granulomas fue 36,3 por ciento (IC95 por ciento de 7,9 por ciento-64,7 por ciento) en los pacientes en que se utilizó bisturí ultrasónico y 36,9 por ciento (IC95 por ciento de 23,0 por ciento-50,9 por ciento) en los pacientes en que se utilizó ligadura convencional. No hubo diferencia estadística (p = 0,974). Conclusiones: El uso de bisturí ultrasónico no disminuyó la incidencia de granulomas del lecho tiroideo, comparado con suturas convencionales. De esta forma, este recurso no aportaría beneficio en la diferenciación ecográfica de nódulos en el lecho tiroideo que pueden corresponder a recidivas tumorales o granulomas cicatriciales.

Evaluación de factores de riesgo foniátricos y generales de disfonía en tiroidectomías / Thyroidectomy dysphonia

Background: Dysphonia is one of the most important and frecuent complication in thyroidectomies. It incidence is between 0 and 20 percent. The frecuency of this complication depends on factors like the preope-ratory diagnosis, goitre volume, surgeon experience and other general factors that theoretically can affect it incidence. Aim: To evaluate a group of preoperatory risk factors usually not considerated that may have relevance in postoperatory dysphonia in thyroidectomies. Patients and Method: Survey and medical records of 56 patients operated between may and july 2009. Results: None of the risk factors included in this study increase de incidence of posthiroidectomy dysphonia. Conclusions: It seems that these theorical risk factors don't have a great influence in the incidence of dysphonia after a thyroidectomy. It can be eventually useful to submit these patients to a direct vocal cord evaluation before surgery, to obtain their real risk.

Introducción: La disfonía es una de las complicaciones en tiroidectomías más importante y frecuente. Su incidencia varía entre 0 y 20 por ciento. Esta incidencia depende de factores como el tipo de diagnóstico preoperatorio, el volumen del bocio, la experiencia del cirujano y otros factores generales que pueden teóricamente influir. Objetivo: Evaluar un grupo no habitualmente considerado de factores de riesgo de disfonía en tiroidectomías. Pacientes y Métodos: Estudio prospectivo con análisis de fichas clínicas y realización de una encuesta preoperatoria en 56 pacientes consecutivos. Resultados: En este estudio no fue demostrado estadísticamente un mayor riesgo de disfonía en pacientes con los factores de riesgos planteados. Conclusiones: Aunque los factores estudiados en esta muestra pueden teóricamente aumentar la incidencia de disfonía postiroidectomía, parecen no ser los más influyentes. Podría ser de utilidad realizar una evaluación dirigida otorrinolaringológica en estos pacientes para objetivar su real riesgo de disfonía postoperatoria.

Hiperparatiroidismo primario con normocalcemia, una asociación de diagnóstico complejo: a propósito de un caso clínico / Normocalcemic hyperparathyroidism: report of one case

We report a 59 years old female with a history of nephrolithiasis and progressive worsening of her bone mineral density. High serum PTH levels were detected, with normal serum calcium. Causes of secondary hyperparathyroidism were discarded. The patient was followed during six years, period in which she maintained elevated serum PTH and normal serum calcium. During the second year of follow up, hydrochlorothiazide was indicated. Serum calcium raised progressively and after six years, it became abnormally high. The patient was subjected to a total left lobe and subtotal right lobe thyroidectomy. The surgeon found a 1.6 mm diameter left parathyroid nodule. After surgery the patient is asymptomatic and is receiving levothyroxine supplementation.

Hiperparatiroidismo primario en el adolescente: caso clínico / Primary hyperparathyroidism in an adolescent: report of one case

We report a 13 year-old mate with a history of multiple fractures and kidney stones. The laboratory showed a hypercalcemia of 11.5 mg/dl, a PTH of 112.6 pg/ml and 24 hour urinary calcium of 571 mg. Bone densitometry showed spine and fémur Z scores of -2.9 and -1.6, respectively, kidney ultrasound showed nephrocalcinosis and a MIBI-SPECT scintigram showed a higher uptake in the ríght lower parathyroid gland. The diagnosis of primary hyperparathyroidism was made and the patient was operated, excising the ríght lower parathyroid gland. After surgery, serum calcium and PTH levels returned to normal values. In children, the proportion of cases with parathyroid hyperplasia is higher than in adults. Therefore, during surgery all four parathyroid glands must be explored. There is also a higher frequency of ectopic adenomas. Family history must be explored to discard the presence of a multiple endocrine neoplasia (MEN I or II), a familial hyperparathyroidism or a syndrome of primary hyperparathyroidism associated to mandibular tumor.

[Primary hyperparathyroidism in an adolescent. Report of one case]. / Hiperparatiroidismo primario en el adolescente: Caso clínico.

We report a 13 year-old mate with a history of multiple fractures and kidney stones. The laboratory showed a hypercalcemia of 11.5 mg/dl, a PTH of 112.6 pg/ml and 24 hour urinary calcium of 571 mg. Bone densitometry showed spine and femur Z scores of -2.9 and -1.6, respectively, kidney ultrasound showed nephrocalcinosis and a MIBI-SPECT scintigram showed a higher uptake in the right lower parathyroid gland. The diagnosis of primary hyperparathyroidism was made and the patient was operated, excising the right lower parathyroid gland. After surgery, serum calcium and PTH levels returned to normal values. In children, the proportion of cases with parathyroid hyperplasia is higher than in adults. Therefore, during surgery all four parathyroid glands must be explored. There is also a higher frequency of ectopic adenomas. Family history must be explored to discard the presence of a multiple endocrine neoplasia (MEN I or II), a familial hyperparathyroidism or a syndrome of primary hyperparathyroidism associated to mandibular tumor.

Cáncer tiroideo: una causa infrecuente de obstrucción de vía aérea superior en niños: Caso clínico / Thyroid carcinoma as a cause of upper airway obstruction in children: Case report

Upper airway obstruction (UAO) can be a severe medical condition with a high mortality in children. We report a 10 year-old girl with UAO due to papillary thyroid carcinoma. The study confirmed a thyroid cancer. The patient was referred to our centre for the evaluation of dyspnea and hoarseness. She was admitted in severe respiratory distress. Her chest X-ray revealed a critical narrowing of the cervical trachea and extensive infiltration of the lung with a miliary pattern; CT scan revealed a thyroid mass with bilateral pulmonary dissemination. An early surgical approach with total thyroidectomy and tracheotomy was performed. The study revealed a thyroid carcinoma. The patient was then referred to a specialized centre to receive radioiodine treatment. Recognition of thyroid carcinoma in children requires a high suspicion index. An early CT scan and fiberoptic assessment could show UAO in many unsuspected lesions.

Características de presentación del microcarcinoma papilar del tiroides. Experiencia retrospectiva de los últimos 12 años / Pathological characteristics of thyroid microcarcinoma. A review of 402 biopsies

Background: Thyroid microcarcinoma is a tumor of 10 mm or less, that should have a low risk of mortality. However, a subgroup of these carcinomas is as aggressive as bigger tumors. Aim: To describe the pathological presentation of these tumors, and compare them with larger tumors. Material and methods: All pathological samples of thyroid carcinoma that were obtained between 1992 and 2003, were studied. In all biopsies, the pathological type, tumor size, the focal or multifocal character, the presence of lymph node involvement and the presence of lymphocytic thyroiditis or thyroid hyperplasia, were recorded. Results: One hundred eighteen microcarcinomas and 284 larger tumors were studied. The mean age of patients with microcarcinoma and larger tumors was 42.7±14 and 49.3±16 years respectively (p <0,001) and 83% were female, without gender differences between tumor types. Mean size of microcarcinomas was 8.6 mm and 116 (98%) were papillary carcinomas. Of these, 109 (94%) were well differentiated and seven (6%) were moderately differentiated. Thirty six (31%) were multifocal and in 10 (8,6%), there was lymph node involvement. The mean size of larger tumors was 23.8 mm and 241 (85%) were papillary carcinomas. Of these, 200 (83%) were well differentiated, and 41 (17%) were moderately differentiated. Eighty five (35%) were multifocal and in 44 (18%) there was lymph node involvement. The prevalence of thyroiditis and hyperplasia was significantly higher among microcarcinomas than in larger tumors (15 and 2.5%, respectively, p <0.001, for the former; 32.4 and 1.7%, respectively, p <0.001, for the latter). Conclusions: In this series, one third of microcarcinomas were multifocal and 10% had lymph node involvement. Therefore, the aggressiveness of these tumors is higher than what is reported in the literature and they should be treated with total thyroidectomy.

Microcarcinoma tiroideo de evolución agresiva: Report of one case / Thyroid microcarcinoma with an aggressive evolution

The treatment of papillary thyroid carcinoma of less than 10 mm diameter is a matter of controversy. The incidental finding of papillary microcarcinomas in autopsies is frequent and some authors postulate that these tumors are biologically inactive and should only be observed. We report a 21 years old woman with a papillary thyroid cancer of 6x5x5 mm and bilateral paratracheal metastases, that was subjected to a total thyroidectomy. She received 200 mCi of radioiodine. Two years after surgery, a new nodule of 9.6 mm diameter was detected by ultrasound, that was treated with a new dose of 200 mCi of radioiodine. One year later a suprasternal mass of 2 cm diameter and 3 enlarged lymph nodes were detected. She was subjected to a surgical lymph node dissection of the neck and the biopsy confirmed the presence of cancer. She received a new dose of 300 mCi of radioiodine. The mother of the patient had a 7 mm thyroid nodule that was also a papillary carcinoma.

La solución intracelular de Bretschneider preserva mejor la función miocárdica que la solución extracelular de St Thomas Nº 1 / Superior myocardial protection of the intracellular solution of Bretschneider compared to the extracellular solution of St Thomas Nº 1

Las soluciones de cardioplejia han reducido en forma significativa el daño isquémico del corazón asociado a la cirugía cardíaca. Sin embargo, existe controversia sobre cual es el tipo de solución ideal. En este estudio comparamos la efectividad entre la solución extracelular de St. Thomas Nº 1 (ST) y la solución intracelular de Bretschneider (BT). En ratas Sprague-Dawley se evaluó la función cardíaca in vitro por el método del corazón aislado de Langerdorff. Los corazones fueron perfundidos con (10ml/kg) de la solución ST o BT, los que posteriormente fueron evaluados luego de 0 horas (sham), 1 hora y 4 horas de isquemia preservados a 4ºC. A un grupo control sin isquemia no se perfundió cardioplejia. Las soluciones se compararon evaluando la incidencia de arritmias, el flujo coronario, la contractilidad (pendiente de la relación tensión-elongación sistólica desarrollada), y distensibilidad miocárdica (cambio de volumen diastólico del ventrículo izquierdo en un rango de presión diastólica entre 0 y 25 mmHg). La solución de BT preservó mejor (p<0,05) la contractilidad miocárdica que la solución de ST, tanto a la hora como a las cuatro horas de isquemia. Por otra parte, a las cuatro horas de isquemia la solución de BT preservó mejor (p<0,05) la distensibilidad miocárdica que la solución de ST. No hubo diferencias en la incidencia de arritmias o en el flujo coronario entre los grupos experimentales. Nuestros resultados muestran que la solución de BT preserva mejor la función sistólica y diastólica que la solución de ST luego de 4 horas de isquemia