Experiencia con una asistencia ventricular pulsátil de larga duración como puente al trasplante cardiaco en adultos / Experience with a long-term pulsatile ventricular assist device as a bridge to heart transplant in adults

Introducción y objetivos: La mayoría de los dispositivos de asistencia ventricular (DAV) de larga duración utilizados actualmente son intracorpóreos y de flujo continuo. Sus principales inconvenientes son el coste elevado y la imposibilidad de ofrecer soporte biventricular. El objetivo de este estudio es describir los resultados de una estrategia de implante de un DAV paracorpóreo de flujo pulsátil como puente al trasplante (PAT) en pacientes adultos. Métodos: Análisis retrospectivo de las características, complicaciones y resultados de una serie unicéntrica de pacientes consecutivos tratados con el DAV EXCOR como PAT entre 2009 y 2015. Resultados: En este periodo se implantaron 25 DAV, 6 de ellos biventriculares. En 12 pacientes la indicación fue directamente PAT y en 13 puente a la decisión debido a la presencia de contraindicaciones potencialmente reversibles o posibilidad de recuperación. Veinte pacientes (80%) alcanzaron el objetivo del trasplante cardiaco tras una mediana de soporte de 112 días (rango 8-239). Las principales complicaciones fueron: infecciosas (52% de los pacientes), neurológicas (32%, la mitad de ellas mortales), hemorrágicas (28%) y fallo del DAV que obligó a cambiar algún componente de este (28%). Conclusiones: El 80% de los pacientes tratados con el DAV EXCOR como PAT alcanzaron el objetivo tras una mediana de soporte de casi 4 meses. Las complicaciones más frecuentes fueron las infecciosas y las más graves las neurológicas. El empleo de estos DAV de flujo pulsátil como PAT, en nuestro medio, es una estrategia factible que consigue resultados similares a los DAV de flujo continuo (AU)

Introduction and objectives: Most long-term ventricular assist devices (VADs) that are currently implanted are intracorporeal continuous-flow devices. Their main limitations include their high cost and inability to provide biventricular support. The aim of this study was to describe the results of using paracorporeal pulsatile-flow VADs as a bridge to transplant (BTT) in adult patients. Methods: Retrospective analysis of the characteristics, complications, and outcomes of a single-center case series of consecutive patients treated with the EXCOR VAD as BTT between 2009 and 2015. Results: During the study period, 25 VADs were implanted, 6 of them biventricular. Ventricular assist devices were indicated directly as a BTT in 12 patients and as a bridge to decision in 13 due to the presence of potentially reversible contraindications or chance of heart function recovery. Twenty patients (80%) were successfully bridged to heart transplant after a median of 112 days (range, 8-239). The main complications included infectious (52% of patients), neurological events (32%, half of them fatal), bleeding (28%), and VAD malfunction requiring component replacement (28%). Conclusions: Eighty percent of patients with the EXCOR VAD as BTT achieved the goal after an average of almost 4 months of support. The most frequent complications were infectious, and the most severe were neurological. In our enivonment, the use of these pulsatile-flow VAD as BTT is a feasible strategy that obtains similar outcomes to those of intracorporeal continuous-flow devices (AU)

Experience With a Long-term Pulsatile Ventricular Assist Device as a Bridge to Heart Transplant in Adults.

INTRODUCTION AND OBJECTIVES: Most long-term ventricular assist devices (VADs) that are currently implanted are intracorporeal continuous-flow devices. Their main limitations include their high cost and inability to provide biventricular support. The aim of this study was to describe the results of using paracorporeal pulsatile-flow VADs as a bridge to transplant (BTT) in adult patients. METHODS: Retrospective analysis of the characteristics, complications, and outcomes of a single-center case series of consecutive patients treated with the EXCOR VAD as BTT between 2009 and 2015. RESULTS: During the study period, 25 VADs were implanted, 6 of them biventricular. Ventricular assist devices were indicated directly as a BTT in 12 patients and as a bridge to decision in 13 due to the presence of potentially reversible contraindications or chance of heart function recovery. Twenty patients (80%) were successfully bridged to heart transplant after a median of 112 days (range, 8-239). The main complications included infectious (52% of patients), neurological events (32%, half of them fatal), bleeding (28%), and VAD malfunction requiring component replacement (28%). CONCLUSIONS: Eighty percent of patients with the EXCOR VAD as BTT achieved the goal after an average of almost 4 months of support. The most frequent complications were infectious, and the most severe were neurological. In our enivonment, the use of these pulsatile-flow VAD as BTT is a feasible strategy that obtains similar outcomes to those of intracorporeal continuous-flow devices.

[Left atrial posterior wall and pulmonary vein refractory periods are associated with atrial fibrillation inducibility in a swine model]. / El período refractario de la aurícula izquierda posterior y de las venas pulmonares se relaciona con la inducibilidad de fibrilación auricular en cerdos.

INTRODUCTION AND OBJECTIVES: Ectopic activity originating inside the pulmonary veins has been associated with paroxysmal atrial fibrillation in some patients. However, the roles played by the pulmonary veins and the posterior wall of the left atrium in maintaining atrial fibrillation are not well understood. METHODS: Our aim was to determine whether there is a correlation between the refractory period of either the lateral wall of the right atrium, the lateral wall of the left atrium, the posterior wall of the left atrium, or the pulmonary veins, and the inducibility of atrial fibrillation in an experimental swine model. We assessed atrial fibrillation inducibility using programmed atrial stimulation before and after intravenous administration of a high dose of methacholine in 20 pigs. RESULTS: Atrial fibrillation was induced in 17 out of the 20 pigs. Univariate analysis showed that there were negative correlations between all refractory periods and atrial fibrillation inducibility. A short refractory period was associated with greater inducibility. In the multivariate analysis, only the refractory periods of the posterior wall of the left atrium and the pulmonary veins were associated with inducibility. We also investigated the relationship between the local atrial fibrillation cycle length and refractory period; the only significant correlation was with the refractory period of the lateral wall of the right atrium (Pearson correlation coefficient 0.97). CONCLUSIONS: In an experimental swine model, the inducibility of atrial fibrillation was found to be associated with the refractory periods of both the pulmonary veins and the posterior wall of the left atrium.

El período refractario de la aurícula izquierda posterior y de las venas pulmonares se relaciona con la inducibilidad de fibrilación auricular en cerdos / Left atrial posterior wall and pulmonary vein refractory periods are associated with atrial fibrillation inducibility in a swine model

Introducción y objetivos. La actividad ectópica desde el interior de las venas pulmonares ha demostrado ser la causa de episodios de fibrilación auricular paroxística en algunos pacientes. Sin embargo, se desconoce el papel exacto de las venas pulmonares y la pared posterior de la aurícula izquierda en la inducibilidad y el mantenimiento de la fibrilación auricular. Métodos. Analizamos la relación entre el período refractario en la cara lateral de la aurícula derecha, la cara lateral de la aurícula izquierda, la cara posterior de la aurícula izquierda y las venas pulmonares con la inducibilidad de fibrilación auricular en un modelo experimental de cerdo. Empleamos estimulación programada, en condiciones basales y tras la administración intravenosa de dosis altas de metacolina, en 20 cerdos en los que se realizó una esternotomía media. Resultados. Se logró inducir fibrilación auricular en 17 de los 20 animales. Todos los períodos refractarios se relacionaron con la inducibilidad de arritmia, con una relación inversamente proporcional en el análisis univariable. Cuanto menor era el período refractario, mayor era la inducibilidad de fibrilación auricular. Cuando se realiza un análisis multivariable, únicamente el período refractario de la pared posterior de la aurícula izquierda y de las venas pulmonares se correlaciona con la inducibilidad. También se ha analizado la relación entre la longitud de ciclo local de la fibrilación auricular y el período refractario. Únicamente hay una buena correlación en la aurícula derecha lateral (coeficiente de correlación de Pearson = 0,97). Conclusiones. En un modelo experimental en cerdos, la inducibilidad de fibrilación auricular se relaciona con los períodos refractarios, tanto en las venas pulmonares como en la cara posterior de la aurícula izquierda

Introduction and objectives. Ectopic activity originating inside the pulmonary veins has been associated with paroxysmal atrial fibrillation in some patients. However, the roles played by the pulmonary veins and the posterior wall of the left atrium in maintaining atrial fibrillation are not well understood. Methods. Our aim was to determine whether there is a correlation between the refractory period of either the lateral wall of the right atrium, the lateral wall of the left atrium, the posterior wall of the left atrium, or the pulmonary veins, and the inducibility of atrial fibrillation in an experimental swine model. We assessed atrial fibrillation inducibility using programmed atrial stimulation before and after intravenous administration of a high dose of methacholine in 20 pigs. Results. Atrial fibrillation was induced in 17 out of the 20 pigs. Univariate analysis showed that there were negative correlations between all refractory periods and atrial fibrillation inducibility. A short refractory period was associated with greater inducibility. In the multivariate analysis, only the refractory periods of the posterior wall of the left atrium and the pulmonary veins were associated with inducibility. We also investigated the relationship between the local atrial fibrillation cycle length and refractory period; the only significant correlation was with the refractory period of the lateral wall of the right atrium (Pearson correlation coefficient 0.97). Conclusions. In an experimental swine model, the inducibility of atrial fibrillation was found to be associated with the refractory periods of both the pulmonary veins and the posterior wall of the left atrium