动物造模,房室传导阻滞动物模型 z-bio 2021-11-29 307

　　[Modeling mechanism] Injecting a certain amount of absolute ethanol or applying video energy to the atrioventricular node of experimental animals will damage the myocardial conduction tissue and create an animal model of atrioventricular block.

　　[Modeling method] Choose a piglet or dog for experiment, fast for 12 hours before surgery, general anesthesia with sodium pentobarbital (30 mg/kg, intraperitoneal injection), tracheal intubation, and ventilator assisted breathing . Connect limb leads for continuous ECG monitoring.

　　1. Open the right chest by chemical resection, enter the pleural cavity through the fourth intercostal space, cut the pericardium to expose the heart, and fix the electrodes with an epicardial protective temporary pacemaker (epicardial protective temporary pacemaker) Left ventricle. To 50). Beats/minute). Inject 1-2 ml of absolute ethanol into the atrioventricular junction (atrioventricular sulcus). After the correct positioning, the heartbeat usually slows down quickly, and the electrocardiogram often shows a complete atrioventricular block pattern. After 30 minutes of observation, the atrioventricular conduction cannot be restored, and it is considered the end of the operation. The chest is closed layer by layer, and the closed drainage of the chest cavity is preserved. You can't do it once, you can repeat it again.

　　2. Perform right femoral vein incision by high-frequency ablation, insert 8F arterial sheath and 7F venous sheath, and send temporary pacing electrodes to the right ventricle to protect temporary pacing (the frequency is set to 50 beats/min). . Feed the electrode and measure the Koch triangle, and obtain a clear and stable His beam potential through discharge ablation. The output power of the ablation method is 50 W per hour, and the discharge time is 30 seconds. If the atrioventricular block occurs within 30 seconds, please combine ablation for another 30 seconds. If incomplete atrioventricular block or accelerated connected heart rhythm occurs within 30 seconds, continue ablation until atrioventricular block occurs, followed by surface and intracavitary electrocardiogram and atrioventricular separation, integrate the ablation for 30 seconds Zhong, until he thinks it can be operated on. end.

　　[Model Features]

　　1. The chemical ablation method does not require cooling or interruption of the circulation. Because it does not require heart surgery or other complicated operations, it is mildly injured, has less bleeding and is tolerable to laboratory animals. This method is easy to learn, timeless, repeatable and has a high success rate.

　　2. Radiofrequency ablation is relatively difficult to operate, expensive, and suitable for large animals, but not for small animals.

　　[Model Evaluation and Application] This model is used to study the etiology of conduction block and evaluate its effectiveness.