RESUMEN
BACKGROUND/AIMS: Chronic myocardial infarction (MI) results in the formation of arrhythmogenic substrates, causing lethal ventricular arrhythmia (VA). We aimed to determine whether mesenchymal stem cells (MSCs) carrying a hepatocyte growth factor (HGF) gene modification (HGF-MSCs) decrease the levels of arrhythmogenic substrates and reduce the susceptibility to developing VA compared with unmodified MSCs and PBS in a swine infarction model. METHODS: The left descending anterior artery was balloon-occluded to establish an MI model. Four weeks later, the randomly grouped pigs were administered MSCs, PBS or HGF-MSCs via thoracotomy. After an additional four weeks, dynamic electrocardiography was performed to assess heart rate variability, and programmed electrical stimulation was conducted to evaluate the risk for VA. Then, the pigs were euthanized for morphometric, immunofluorescence and western blot analyses. RESULTS: The HGF-MSC group displayed the highest vessel density and Cx43 expression levels, and the lowest levels of apoptosis, and tyrosine hydroxylase (TH) and growth associated protein 43 (GAP43) expression. Moreover, the HGF-MSC group exhibited a decrease in the number of sympathetic nerve fibers, substantial decreases in the low frequency and the low-/high- frequency ratio and increases in the root mean square of successive differences (rMSSD) and the percentage of successive normal sinus R-R intervals longer than 50 ms (pNN50), compared with the other two groups. Finally, the HGF-MSC group displayed the lowest susceptibility to developing VA. CONCLUSION: HGF-MSCs displayed potent antiarrhythmic effects, reducing the risk for VA.
Asunto(s)
Arritmias Cardíacas/terapia , Células de la Médula Ósea/citología , Factor de Crecimiento de Hepatocito/genética , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Animales , Apoptosis , Arritmias Cardíacas/patología , Arritmias Cardíacas/fisiopatología , Sistema Nervioso Autónomo/fisiopatología , Supervivencia Celular , Estimulación Eléctrica , Regulación de la Expresión Génica , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Infarto del Miocardio/patología , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Neovascularización Fisiológica , PorcinosRESUMEN
BACKGROUND: Ventricular fibrillation is the main cause of sudden cardiac death among patients with acute myocardial infarction (AMI). Substantial benefits could be obtained by both researchers and practitioners if an AMI reperfusion-ventricular fibrillation-cardiac arrest model were established. METHODS: Twenty swine were anesthetized and underwent occlusion of the left anterior descending branch for 90 minutes prior to blood reperfusion. Throughout this process, continuous 12-lead electrocardiography (ECG) was used to monitor heart rate, rhythm, and electrocardiogram alteration. Thereafter, AMI was confirmed by ECG and left ventricular angiography. Heart tissue was collected for pathological analysis, and for evaluation of the establishment of a model of AMI reperfusion. RESULTS: Seven swine died during the model establishment, and the 13 surviving swine were proven to have myocardial infarction; nine of those survivors had ventricular fibrillation-cardiac arrest after reperfusion based on the electrocardiograph and pathological examination. CONCLUSION: Blocking the left anterior descending branch by inflation of an over-the-wire coronary balloon catheter in swine can result in successful establishment of a swine model of AMI and reperfusion-ventricular fibrillation-cardiac arrest, with good reproducibility and a high survival rate.
