动物造模,房颤小型猪模型 z-bio 2023-09-26 1047

　　Due to the autonomic or conductive disorders of the heart, changes in heart activity frequency and rhythm, as well as abnormal impulse conduction sequence, can lead to arrhythmia. Many human diseases can cause arrhythmia, and atrial fibrillation is more common in clinical practice. Ventricular tachyarrhythmia and ventricular fibrillation often threaten human life. So in clinical practice, it is often necessary to replicate animal models of arrhythmia for research.

　　1. Materials and Methods

　　(1) Animals were randomly selected from the 5th generation experimental small pigs domesticated and bred by the Experimental Animal Research Institute of Guiyang University of Traditional Chinese Medicine, healthy and disease-free, weighing 14.0 ± 1.5kg.

　　(2) Instruments include Shanghai made XJJ-II cardiac emergency monitor, domestically produced SC-II electric ventilator, CT-I multifunctional cardiac program pacing device, Guizhou made LFYC-II arrhythmia treatment device, specially designed gF six stage catheter, needle electrode, and fish clip.

　　(3) Determination method: All Guizhou miniature pigs fasted one night before the experiment, and were anesthetized intraperitoneally with pentobarbital sodium 30-40mg/kg in the morning of the experiment. Maintain a supine position and perform a femoral vein incision, connecting the infusion bottle to maintain patency. Input physiological saline. Insert a tracheal catheter through the mouth and connect it to a domestically produced SC-II electric ventilator. Insert needle electrodes in the limbs and chest, connect the lead wire to the power supply, and connect to the Shanghai made XJJ-II heart monitor. Corrected standard voltage (1mV=10mm), paper feeding speed (25mm/s). A specially designed gF six stage catheter is placed through the mouth into the esophagus, and the distal two electrodes are connected to the LFYC-II arrhythmia treatment device. The atrial pacing frequency is slightly faster than the animal's own heart rate, and the catheter position and pacing voltage are continuously adjusted to find the lowest catheter position and threshold that can capture the atrium 1:1 for pacing. Fix the pacing catheter, with two electrodes at the proximal end of the catheter used for electrocardiogram detection and recording. Use the self modified XJJ-II cardiac emergency monitor for continuous electrocardiogram monitoring and recording, and provide electrical energy pulses for cardioversion shocks. Before the experiment, 12 lead maps were recorded for each animal, including I, II, III, aVR, aVL, aVF, and V1-6, for reference (see the normal electrocardiogram study of Guizhou miniature pigs).

　　① Use 60 drops/min of 25-10000 units of acetylcholine for continuous intravenous infusion. Five minutes ago, atrial fibrillation (Af) was induced by stimulating the atrium with a matrix square frequency pulse of 800-1000 times/min through the esophagus. The recorded automatic cardioversion time was observed, and Af was then induced again. Within a shorter time than the automatic cardioversion, direct current synchronous electric shock was used to cardioversion through the esophagus, and the energy threshold for converting Af was recorded.

　　② Push the esophageal electrode catheter further 2cm, with 1-2 distal electrode combinations as the cathode and 4-5 other electrode combinations as the anode. Approximately 40ms before the peak of the T-wave on the electrocardiogram, 10-20MJ of energy is emitted through the esophageal electrode for asynchronous DC shock replication of VTA (ventricular tachyarrhythmia). After successful replication of VTA, ventricular tachycardia (VT) was converted, and synchronized shock was performed with a retrograde increase in energy from 0.25MJ; Conversion to ventricular flutter (VF) and ventricular fibrillation (Vf)