动物造模,心律失常 zi-bio 2024-02-18 1188

　　【 Modeling mechanism 】 Electrical stimulation can change the membrane conductivity of myocardial cells, increase the heterogeneity of myocardial repolarization, and make the stimulation more prone to fibrillation during the vulnerable period. The ventricular fibrillation threshold, which is the minimum stimulation intensity required to induce ventricular fibrillation at a certain moment during the vulnerable period of electrical stimulation, is often used as a reflection of ventricular fibrillation and is widely used in basic and clinical trial research.

　　The model has been successfully replicated on various animals such as mice, rats, rabbits, dogs, and pigs. Small animals usually require thoracotomy. Animal anesthesia fixed tracheal intubation, exposing the heart through thoracotomy in the fourth intercostal space on the left side, clipping the open heart, fixing the positive and negative electrodes of the stimulation electrode at the apex of the left ventricle and the bottom of the right ventricle, recording the electrocardiogram, gradually increasing the stimulation intensity, and recording the voltage value when ventricular fibrillation occurs. Large animals (such as dogs, pigs, etc.) can undergo cardiac catheterization under the guidance of an X-ray machine. After anesthesia, tracheal intubation is performed, with limb leads connected to electrocardiograms (ECG). Under the guidance of the X-ray machine, two 6F 4-pole electrodes are placed at the right ventricular apex or right ventricular outflow tract and right atrium through the femoral artery and femoral vein, respectively, and connected to a multi-channel physiological recorder. S1S1/S1S2 stimulation is given to induce ventricular arrhythmias.

　　【 Model Features 】 When normal myocardial tissue is subjected to programmed electrical stimulation, the ventricular fibrillation threshold is higher, making it less likely to cause ventricular arrhythmias. However, in diseased myocardial tissue, the ventricular fibrillation threshold is lower, making it more likely to induce ventricular arrhythmias.

　　Model evaluation and application are widely used to study the mechanisms and treatments of ventricular arrhythmias.