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Objetivo Estudiar la contribucion de la biomecanica computational al tratamiento de las enfermedades cardiovasculares (aneurismas de aorta e insuficiencia cardiaca): estudios predictivos, decisiones terapeuticas, evaluacion de resultados y diseno de tecnicas quirurgicas. Metodos Hemos desarrollado X-Flow que obtiene imagenes de aorta y ventriculo izquierdo (VI) de resonancia magnetica y tomografia computarizada. El tratamiento de las imagenes esta compuesto por un generador de geometria 3D, modulo de simulacion e interfase ergonomica. La innovacion tecnologica esta basada en smoth particle hydrodinamics (SPH), boundary element method (BEM) y elementos finitos (FEM). Estas tecnologias aportan geometria 3D del propio paciente y no un modelo generico, simulacion de fluidos no newtonianos y del tejido elastico. Hemos estudiado la validacion de esta innovadora tecnologia con: a) los estudios computer fluid dynamics (CFD) con level set por umbrales de intensidad, tecnicas heuristicas con NURBS y simulacion con ecuacion de Navier-Stokes, y b) los resultados clinicos del registro SVRIR y de la experiencia de aneurismas de aorta de este grupo cooperativo. Resultados Los resultados correlacionando los CFD con la tecnologia X-Flow y los resultados iniciales de los registros clinicos han validado esta tecnologia que ha demostrado ofrecer solucion a problemas no resueltos: modelos de viscosidad turbulenta, tratamiento de problemas de dos fases, analisis dinamico de esfuerzos y deformaciones en estructuras. Conclusion Estos resultados validan la tecnologia X-Flow, que ofrece soluciones a problemas aun sin resolver y demuestra la capacidad y posibilidades de alcanzar los objetivos propuestos en los estudios de los aneurismas de aorta y el VI con insuficiencia cardiaca.

We report a patient with a mitral insufficiency due to myxomatous valve change, with a regurgitation murmur heard principally at aortic area and radiating to the neck base. Even though the topography of the murmur seemed to suggest aortic stenosis, the other auscultation findings and the initial clinical tests clearly supported its source in a mitral insufficiency. The echocardiography allowed us not only to confirm our suspicion, but also to explain this auscultation finding mechanism, to show a severe mitral insufficiency with a anterior and medial jet, which struck the aorta and atrial septum. The surgery found a clear aortic vibration, which disappeared after implanting the mitral protheses. Our case illustrates the value of new diagnostic image techniques to complement the semiologic findings.

J Thorac Cardiovasc Surg 1999;117:185

A 70-year-old man with ischemic cardiomyopathy underwent heart transplantation in July 1990. The postoperative course was uneventful, and the patient maintained normal systolic and diastolic ventricular function and New York Heart Association (NYHA) functional class I. In March 1993, after an episode of diarrhea, the patient was admitted with signs and symptoms of heart failure. The echocardiogram showed a left …

La aparición de una insuficiencia valvular mitral funcional en el seno de una miocardiopatía isquémica o dilatada es un signo de mal pronóstico con una elevada mortalidad y morbilidad y una reducción significativa de la esperanza de vida. La válvula mitral es anatómicamente normal, sin lesiones orgánicas en sus estructuras, por lo que el mecanismo de la regurgitación valvular se explica por los cambios en la geometría que sufre el ventrículo izquierdo. La miocardiopatía isquémica produce un remodelado del ventrículo que pierde su configuración normal, produciéndose una separación de ambos músculos papilares que traccionan de los velos ocasionando un déficit de coaptación y la aparición de la insuficiencia valvular.Probablemente, el tratamiento quirúrgico es la única opción terapéutica adecuada para corregir la regurgitación valvular y normalizar el pronóstico de estos pacientes. Se han diseñado diversas estrategias quirúrgicas encaminadas a reparar la lesión valvular, por una parte, y a normalizar la geometría ventricular, por otra. No obstante, en la actualidad aún no disponemos de una solución quirúrgica definitiva que pueda ser considerada el «patrón oro».The appearance of functional mitral valve insufficiency in the setting of ischemic or dilated cardiomyopathy is an indicator of bad prognosis, with increased early and mid-term mortality and morbidity and with a significant decrease in life expectancy. In these patients, the mitral valve is anatomically normal, without organic lesions, and this is why the mechanism of valve regurgitation is complex and can be explained by the changes in the left ventricle geometry. Ischemic cardiomyopathy produces left ventricle remodeling, with increased sphericity and displacement of both papillary muscles. All of these phenomena cause valve leaflet tethering, especially in the posterior leaflet.At present, surgical treatment is the only therapeutic option for these patients in order to treat mitral regurgitation. Diverse surgical strategies have been designed to repair mitral regurgitation and to restore left ventricular geometry. However, at present there is not a definitive surgical solution that can be considered the “gold standard”.

En relación con los mecanismos de acción de la cardiomioplastia dinámica (CMPD), una reducción del estrés mecánico contribuye a reducir los niveles de apoptosis miocárdica. La recurrencia de la dilatación del ventrículo izquierdo, observado en pacientes con IC congestiva, determina un ciclo vicioso de estrés parietal y pérdida celular por apoptosis con dilatación progresiva de las cámaras ventriculares. Los resultados a largo plazo de la CMPD se hallan limitados por la condición preoperatoria de los pacientes y por la incidencia de muerte súbita.La cardiomioplastia ofrece una cierta seguridad para ser utilizada como un puente al trasplante cardíaco en pacientes críticos con el fin de mejorar su calidad de vida a la espera de un órgano para el injerto. Por otra parte, la cooperación entre técnicas de regeneración celular e ingeniería de tejidos pueden ejercer beneficios funcionales ya que estos materiales proveerían de soporte evitando una remodelación excesiva y dilatación consecuente del ventrículo. Los mecanismos mencionados son algunos de los efectos demostrados por la aplicación de la CMPD con el dorsal ancho.Concerning the mechanisms of action, a reduction in mechanical stress seems to contribute to a reduced level of myocardial apoptosis after cardiomyoplasty. Subsequent recurrence of left ventricular dilatation due to detrimental evolution of the underlying myocardial tissue observed in some cases could, in turn, instigate a return to pathological levels of wall stress, and to the vicious cycle of apoptotic cell loss and further progressive left ventricular enlargement. Long-term results of dynamic cardiomyoplasty are limited by the patient preoperative condition and by a high incidence of sudden cardiac death.Cardiomyoplasty offers a relative secure mid to long-term bridge to heart transplant allowing critically ill patients to significantly improve their quality of life while waiting for heart donor. On the other hand, mixture of cell transplantation and tissue engineering can bridge functional benefits is that this implanted material should provide a supporting “band-aid” scaffolding effect, which can limit the spread of the infarcted area, preventing excessive remodeling and dilatation of the ventricle. The mechanisms mentioned above were one of the main effects demonstrated by the application of latissimus dorsi cardiomyoplasty.

La terapia celular es una de las áreas más prometedoras del tratamiento de enfermedades con escasas expectativas de curación. La insuficiencia cardíaca es una de las enfermedades que más se pueden beneficiar de este tratamiento. El objetivo es regenerar el músculo, reducir la apoptosis, aumentar la expresión del colágeno intersticial y conseguir una producción efectiva de nuevos vasos que aseguren una nutrición adecuada a la zona afectada. Los estudios multidisciplinarios en curso modificarán las estrategias de tratamiento, antes de elaborar «guías clínicas», con evidencias científicas suficientes para obtener el consenso.La regeneración cardíaca no debe quedar reducida al implante de células y es necesaria también la regeneración de la matriz extracelular. Este abordaje matriz-células probablemente se convierta en la apuesta del futuro. La ingeniería tisular cardíaca se encuentra ante el desafío de reconstruir o regenerar las pérdidas anatómicas, evitar o retrasar la progresión del remodelado ventricular y revertir la reducción funcional.Cellular therapy is one of the most promising areas in the treatment of terminal diseases with short life expectancy. Cardiac insufficiency is one of those that could benefit the most from this form of treatment. The aim is to regenerate the muscle, reduce apoptosis, increase the expression of interstitial collagen and to get an effective production of new vessels that may ensure an accurate feeding of the affected zone. Multidisciplinary studies in course will modify the treatment strategies before elaborating “guidelines” with enough scientific evidence to reach consensus.Cardiac regeneration must not be restrained to cell implantation and it is also needed after the regeneration of the extracellular matrix. This approach “matrix-cell” will probably become the bet in future. Cardiac tissue engineering faces the challenge of rebuilding or regenerating the anatomic losses, to avoid or delay the progression of ventricular remodelling and to restore functional reduction.

La terapia celular con células madre, como estrategia para regenerar tejidos dañados, es una de las áreas más prometedoras en el tratamiento de enfermedades con escasas o nulas expectativas de curación. La insuficiencia cardíaca, principalmente de origen isquémico, es una de las enfermedades que más se pueden beneficiar de esta estrategia. El objetivo es regenerar el músculo, reducir la apoptosis, aumentar la expresión del colágeno intersticial e inducir la generación de nuevos vasos. la terapia celular cardíaca ha sido propuesta con una gran variedad de células angiogénicas y miogénicas: mioblastos esqueléticos, células mononucleares y mesenquimales de médula ósea, progenitores endoteliales circulantes, células derivadas del estroma de la grasa o del endometrio, células mesoteliales y pluripotenciales (induced pluripotent stem cells [iPS]). las indicaciones incluyen a pacientes con miocardiopatía isquémica o dilatada, enfermedad de Chagas, insuficiencia mitral isquémica y miocardiopatía diabética. Los abordajes son quirúrgicos, con inyección periinfarto, intracoronario y endoventricular percutáneo. Los mecanismos de acción propuestos son la reducción del tamaño de la cicatriz del infarto, el aumento de la viabilidad miocárdica, la limitación del remodelado ventricular y los efectos paracrinos. Sin embargo, los resultados clínicos muestran sólo mejoras muy limitadas de la función sistólica y del remodelado ventricular. El desarrollo de estrategias que mejoren la supervivencia y la diferenciación celular deben ser prioritarias, tales como el preacondicionamiento con electroestimulación o la ingeniería tisular con el objetivo de desarrollar un miocardio bioartificial.Stem cell therapy, as a strategy to regenerate injured tissues, has emerged as one of the most promising areas for the treatment of illnesses with low possibilities of treatment. The heart failure, mainly of ischemic ethiology, is one of the diseases that more can benefit from this therapeutic strategy. The aim is to regenerate the muscle, reduce apoptosis, increase the expression of the collagen and get an effective production of new vessels. This approach is undergoing with a variety of myogenic and angiogenic cells: skeletal myoblasts, mononuclear and mesenchymal bone marrow cells, circulating blood-derived progenitors, endometrial or adipose-derived stromal cells, mesothelial cells and induced pluripotent stem cells (iPS). The indications concern patients with ischemic cardiomyopathy, idiopathic dilated cardiomyopathies, Chagas heart disease, ischemic mitral regurgitation and diabetic cardiomyopathy. The approaches for cell delivery are surgical performing in the periinfarct area, intracoronary and endoventricular catheter-based cell delivery. The proposed mechanisms of action are reduction of the size and fibrosis of infarct scars, improvement of myocardial viability, limitation of ventricular remodeling, improvement of ventricular compliance and paracrine effects. However, the clinical results have reported only limited improvement in systolic function and remodeling. The development of strategies for improving cell survival and differentiation should be encouraged, such as preconditioning procedures with cell electrostimulation or by using tissue engineering in order to create a bioartificial myocardium.

La insuficiencia cardíaca (IC) es uno de los problemas de salud de mayor relevancia. El trasplante cardíaco es el abordaje de la IC grado D. Sin embargo la desproporción receptores-donantes restringe el número de trasplantes y ha inducido el desarrollo de nuevas estrategias terapéuticas. El modelo de anatomía y función cardíaca basado en la hipótesis de Torrent Guasp ha conseguido que el estudio de la acción mecánica cardíaca recupere la importancia que le corresponde. Esta hipótesis ha llevado a revisar conceptos clásicos tales como que la banda miocárdica sería generadora de la reducción tridimensional. El objetivo de esta publicación es destacar el desarrollo de nuevas estrategias terapéuticas de la IC, integrando la biología, las nuevas tecnologías médicas y las bases anatómicas de torrent Guasp.Este número quiere ser un recordatorio de Torrent Guasp. Su aportación científica crucial para la cardiología moderna, su calidad científica y humana, nos ha llevado a dedicarle un modesto homenaje póstumo.Chronic heart failure is one of the major health care issues. Heart transplantation is the approach for patients in class D. Furthermore, the disproportion between recipients and donnors restricts the number of cardiac transplants and has generated alternative treatments.The hypothesis of Torrent Guasp has achieved that the study of cardiac mechanical action to regain the importance it deserves. This hypothesis has led to revise classic concepts: myocardial band without fixed support points generating a three dimensional reduction.The objective of this article is emphasized the development of the therapeutic strategies designed to integrate biology, new medical technologies and the anatomical model of Torrent Guasp. This edition would like to be a reminder of the crucial contribution to cardiology by Torrent Guasp, in addition to his scientific and personal quality.

Serial myocardial imaging using thallium Tl 201 was performed in the early follow-up of two patients with orthotopic cardiac transplantation. In one patient, non-homogeneous uptake, small defects and an irregular myocardial edge were observed during a moderately acute rejection crisis revealed by endomyocardial biopsy. The abnormal gammagraphic findings and histological changes were coincident and exhibited a parallel reversal. We emphasize the connection between these two events. The mechanisms which could explain these phenomena are discussed.

We present 2 cases of delayed diagnosis of rupture of the right hemidiaphragm caused by blunt thoracic trauma, in which herniation of the liver toward the thoracic cavity had occurred. Both patients showed signs of noncardiogenic hepatic venous outflow obstruction. Venous outflow returned to normal on reintroduction of the liver into the abdominal cavity and closure of the defect in the diaphragm. The pathogenesis, diagnosis, and treatment of this problem are discussed.

The aim of this investigation was to study the effect of a new pulsatile pump for extracorporeal circulation (ECC) on platelet count and platelet function with respect to a Biomedicus centrifugal pump. Thirteen pigs, 8 in the pulsatile group (PG) and 5 in the centrifugal group (CG), underwent a partial extracorporeal circulation lasting 3 h. The animals were sacrificed 3 h post-ECC. The platelet study was both quantitative (platelet count) and qualitative (platelet function analysis) by assessing the closure time (CT) with a PFA-100 system. The decrease in platelet number from basal to 3 h post ECC was only significant in CG (p = 0.009). The platelet function was impaired in both groups, but the value of CT with col/ADP increased significantly only in CG (p < 0.001). The increase of CT with col/EPI was greater in CG (p = 0.07) than in PG (p = 0.2). The results indicated that the new pulsatile pump preserves platelets quantitatively and qualitatively well compared to a Biomedicus pump.

Cardiac regeneration requires a complex cascade of events. Stem cell therapy and tissue engineering are newly emerging tools with promising potential for recover or replace of damaged cardiac tissue. There are many factors, most of them still no clarified, that limit the effectiveness of these treatments and their translation to the clinic. Cells should graft, survive and functionally integrate to the target organ in order to have a chance to restore its function. As in original tissues, a complex and well defined set of signals, many of them coming from the extracellular matrix, is required for normal cell physiology. Biomaterials science gives us important tools to build this extracellular matrix. Functionalized 3D systems can provide the correct environment and act as a delivery system for genes or gene products, guiding the therapeutic cells to the functional phenotype.

Dynamic cardiomyoplasty is a relatively new surgical procedure by which a transformed fatigue-resistant skeletal muscle wrapped around the heart is stimulated to contract in synchrony with it, thereby augmenting the ventricular functions of a failing heart. We performed a cardiomyoplasty with latissimus dorsii (LD) in a patient who was refused the heart transplant programme because of pulmonary hypertension and psychosocial contraindications. The patient was 34 years old, functional class grade IV of the New York Heart Association (NYHA), with a three-month history, due to ischemic cardiomyopathy with multiple vessels affected, 10% ejection fraction, arteriolar pulmonary resistance of 7.5 U Wood. Cardiomyoplasty was performed after training the LD muscle for four weeks. One week later the pacemaker was programmed in a DDD mode: amplitude 3.75 V, pulse duration 0.50 ms, AV delay 175 ms. The patient reached functional class grade I-II (NYHA). Inotrope support was discontinued and great clinical improvement was noted. The ejection fraction rose from 10% to 30%. Echocardiographic left ventricular outflow tract velocity increased from 0.33 m/s to 0.60 m/s. These values were compared with radionuclide angiocardiography and echocardiography evaluations. The great clinical improvement and positive changes in left ventricular parameters suggest that cardiomyoplasty is useful in the treatment of some cases of dilated or ischemic cardiomyopathy as an alternative to heart transplantation. Long term follow-up is necessary to evaluate this procedure.