心脏传导阻滞（Heart block）.docVIP

心脏传导阻滞（Heart block） Sixth heart block The conduction of impulses at any part of the heart conduction system can slow down or block. If it occurs between the sinoatrial node and the atrium, it is called the sinoatrial block. Between atrial and ventricular, it is called atrioventricular block. Located in the atrium, called atrial block. Located in the heart chamber called interior block. According to the severity of the block, it is usually divided into three degrees. The conduction time of the first degree conduction block is prolonged, and the whole impulse can still transmit. Second degree conduction block can be divided into two types: Mohs (Mobitz), type I and type ii. Type I block is characterized by progressive prolongation of conduction time until one impulse does not pass; type II block is intermittent conduction block. The third degree is called complete block. At this point, all impulses cannot be transmitted. The sinoatrial block is described in section second of this chapter. Atrioventricular block, atrioventricular block Atrioventricular block (atrioventricular block), also known as atrioventricular block, refers to the atrioventricular junction from the physiological refractory period, the conduction of atrial impulses delayed or can not conduction to the ventricles. Atrioventricular block can occur in different parts of the atrioventricular node, his bundle, and the bundle branch. [pathogeny] A typical type of atrioventricular block (Mohs type I) may occur in normal subjects or athletes, and is associated with increased vagal tone, often at night. Other causes of atrioventricular block lesions: acute myocardial infarction, coronary artery spasm, viral myocarditis, endocarditis, cardiomyopathy, acute rheumatic fever, calcific aortic stenosis, cardiac tumors (especially pericardial mesothelioma), congenital cardiovascular disease, hypertension, cardiac surgery, electrolyte disorders, drug poisoning, Lyme disease (Leptospira infection, can cause myocardit