Tratamiento endovascular de la disección aórtica tipo B mediante endoprótesis / Endovascular treatment of type B aortic dissection

Background: Dissections that involve the ascending aorta are classified as type A, regardless of the site of the primary intimal tear, and all other dissections as type B. Type B dissections can have fatal ischemic and hemorrhagic complications. In the chronic state, dilatation and rupture can be mortal. Endovascular surgery is a therapeutic alternative, considering the high rate of complications of conventional surgery Aim: To report the results of endovascular treatment of type B aortic dissection. Material and methods: Report of 36 treated patients (30 males) aged 43 to 87 years, with a type B aortic dissection. Seventy eight percent were hypertensive and 39 percent smoked. The diagnosis was conñrmed by CAT sean. Acute patients were treated for complications and chronic patients, for dilatation. In the operating room, an endoprothesis was placed through the femoral artery, to cover the tear. The tear was located and the lumens were differentiated using angiography and transesophageal echocardiography. Results: All procedures were successful. In 16 acute dissections the indications were malperfusion syndrome or unmanageable hypertension in seven patients and imminent rupture or persistent pain in nine. Twenty chronic patients were operated due to dilatation (mean 6 cm). One patient died due to cardiac failure. One patient had a transient paraparesia and two had pulmonary embolism. No patient died in a follow up períod ranging from 2.5 to 74 months. Four patients required a new aortic endovascular procedure due to progressive dilatation or endoleak. Conclusión: Endovascular treatment of type B aortic dissection has good immediate andlong term results.

Efecto de un inhibidor tirosina kinasa (imatinib) en pacientes con tumores estromales gastrointestinales metastásicos: Experiencia preliminar / Treatment of metastatic gastrointestinal stromal tumors with Imatinib: Report of four cases

Gastrointestinal stromal tumors (GIST) have mutations of the tyrosine kinase receptor. When they are localized, the treatment of choice is surgical excision, but advanced tumors have a limited response to chemo or radiotherapy. Imatinib (STI571 or Glivec®) is a selective inhibitor or tyrosine kinase proteins that has been used successfully in the treatment of advanced GIST. We report four patients (two women) with a metastatic GIST that were treated with Imatinib 400 mg day and followed for 40 months. The disease tumor stabilized in three patients and in one it had an initial reduction and progressed at the end of follow up. Therefore Imatinib can be a therapeutic alternative in patients with metastatic GIST.

Tratamiento "híbrido" del aneurisma tóraco-abdominal: revascularización visceral extraanatómica e inserción de endoprótesis / Extra anatomical revascularization and endovascular stent-grafting for thoracoabdominal aneurysm repair: Report of four cases

Surgical treatment of thoracoabdominal aneurysms is a big technical challenge with a high rate of complications and mortality. It requires a large exposure and transient interruption of vital organ perfusion during its repair. Endovascular repair is a less invasive alternative available over the last decade. We report four male patients aged 44 to 76 years, with thoracic aortic aneurysms and involvement of visceral aorta, treated with a two stage procedure. During the first stage, a retrograde revascularization of the superior mesenteric and renal arteries from the infrarenal aorta was done, associated in two cases to a concomitant repair of an infrarenal aortic aneurysm. In the second stage, an endovascular graft was placed through the femoral artery, from the segment proximal to the aneurysm to the infrarenal aorta, above the origin of the visceral artery reconstructions, excluding the aneurysm from circulation. In one patient, both stages were concomitant and in three the second stage was delayed. One patient presented a postoperative bleeding that required reintervention without adverse consequences. No patient died, presented paraplegia or deterioration of renal function. After follow up of 6 to 20 months, there is no evidence of aneurysm growth or complications derived from the procedure.

Tratamiento endovascular de aneurisma aórtico abdominal: resultados en 80 pacientes consecutivos / Endovascular repair of abdominal aortic aneurysm: Results in 80 consecutive patients

Background: Endovascular repair of abdominal aortic aneurysms (AAA) avoids laparotomy, shortens hospital stay and reduces morbidity and mortality related to surgical repair, allowing full patient recovery in less time. Aim: To report short and long term results of endovascular repair of AAA in 80 consecutive patients treated at our institution. Patients and Methods: Between September 1997 and February 2005, three women and 77 men with a mean age 73.6±7.7 years with AAA 5.8±1.0 cm in diameter, were treated. The surgical risk of 38 percent of patients was grade III according to the American Society of Anesthesiologists classification. Each procedure was performed in the operating room, under local or regional anesthesia, with the aid of digital substraction angiography. The endograft was deployed through the femoral artery (83.7 percent bifurcated, 16.3 percent tubular graft). A femoro-femoral bypass was required in 11.3 percent of cases. Follow-up included a spiral CT scan at 1, 6 and 12 months postoperatively, and then annually. Results: Endovascular repair was successfully completed in 79/80 patients (98.7 percent technical success). The procedures lasted 147±71 min. Length of stay in the observation unit was 20.6±13.5 h. Blood transfusion was required in 10 percent. Sixty two percent of the patients were discharged before 72 h. One patient died 8 days after surgery due to a myocardial infarction (1.3 percent). During follow-up (3-90 months), 1 patient developed late AAA enlargement due to a type I endoleak, requiring a new endograft. No AAA rupture was observed. Survival at 4 years was 84.2 percent (SE =9.2). Endovascular re-intervention free survival was 82.7 percent (SE =9.5). Conclusion: Endovascular surgery allows effective exclusion of AAA avoiding progressive enlargement and/or rupture and is a good alternative to open repair. Close and frequent postoperative follow up is mandatory.

Coronariografía no invasiva mediante tomografía axial computada multicorte / 16 detector computed tomagraphy for coronary angiography

Antecedentes: La tomografía axial computada de 16 detectores de las arterias coronarias (TAC Coronario) ha emergido recientemente como una alternativa diagnóstica a la coronariografía invasiva (CI). Objetivo: Estudiar la exactitud del TAC coronario de 16 detectores para pesquisar la presencia o ausencia de estenosis coronaria en distintos tipos de pacientes, mediante su comparación con la CI. Métodos: A un total de 55 pacientes (46 hombres, 9 mujeres, promedio 57 +/-12 años) en quienes se realizó una CI electiva, se les realizó un TAC coronario. Se analizó específicamente la presencia de lesiones 50 por ciento y se compararon estos resultados con los obtenidos mediante la CI cuantitativa. Resultados: Cincuenta pacientes requirieron beta bloqueo, obteniéndose una FC promedio de 57 lpm. En los segmentos principales se objetivaron 61 lesiones significativas por CI, de las cuales 52 (85,2 por ciento) fueron correctamente detectadas por el TAC coronario. La sensibilidad, especificidad, LH(+) y LH(-) del examen fueron 85 por ciento, 97 por ciento, 33 y 0.15, respectivamente. La presencia o ausencia de enfermedad coronaria significativa fue correctamente diagnosticada en 50 de los 55 pacientes (91 por ciento). Conclusión: El TAC coronario de 16 detectores es un examen sensible y específico para el diagnóstico de estenosis significativas de los segmentos principales del árbol coronario.

Background: Invasive coronary arteriography (ICA) is the gold standard to assess coronary artery stenosis. Sixteen detector computed tomography (Coronary CT) has recently been introduced as a less invasive diagnostic alternative. Aim: To assess the reliability of Coronary CT in detecting coronary stenosis among different types of patients by comparing the results with those obtained by ICA. Methods: 55 patients (age 57+/-12 years, 46 males) who underwent ICA had also a coronary CT. Beta blockade was used to obtain a heart rate < 65 beats per min. The presence of significant stenosis (•'3d50 percent of luminal diameter measured by quantitative angiography) was compared between methods.Results: Adequate coronary images were obtained in 53 of 55 patients with coronary CT; a total of 715 coronary segments were available for analysis. Fifty patients required beta blockade and the mean heart rate was 57 beats per min. Fifty-two out of 61 main segment stenosis were detected by coronary CT (85.2 percent). Sensitivity, specificity, LH+ and LH- of coronary CT were 85 percent, 97 percent, 33 and 0.15, respectively. The presence or absence of significant lesions was correctly diagnosed in 50 of the 55 patients (91 percent). Conclusion: 16 detector coronary CT is a sensitive and specific method to diagnose main segment significant coronary stenosis.

Uso del sistema de soporte hepático extracorpóreo MARS en la falla hepática aguda sobre crónica: caso clínico / Extracorporeal liver support with mars in acute on chronic liver failure: a clinical report

El sistema MARS (“molecular adsorbent recirculating system”) es un sistema de soporte hepático extracorpóreo, con capacidad de eliminar substancias liposolubles ligadas a la albúmina y compuestos hidrosolubles involucrados en la patogenia de la encefalopatía, alteraciones hemodinámicas y metabólicas de la falla hepática aguda. Se presenta un paciente de 53 años con una cirrosis hepática secundaria a infección por virus C de la hepatitis, que desarrolló un carcinoma hepatocelular y un deterioro importante de las funciones hepática y renal, después de dos procedimientos de quimioembolización arterial del tumor. El paciente fue considerado para un trasplante hepático urgente y fue sometido a MARS en espera de la cirugía. Se realizaron 4 sesiones de 24, 12, 8 y 12 horas, respectivamente. Inmediatamente después del primer tratamiento se produjo un descenso significativo de los niveles séricos de bilirrubina, remisión de la encefalopatía hepática, mejoría de la función renal y parámetros hemodinámicos. Cuatro días después de la última sesión se realizó el trasplante hepático sin complicaciones y 20 meses después el paciente está en buenas condiciones. MARS representa una nueva técnica de soporte hepático que puede ser de utilidad en pacientes con cirrosis descompensada en espera de un trasplante de hígado.