How do you get second degree atrioventricular block?

The causes of second-degree atrioventricular block include the following: 1. Increased vagus nerve tone. 2. Adverse effects of drugs: Many drugs can prolong the effective refractory period of atrioventricular node, such as digitalis drugs, beta blockers, quinidine, procainamide, propafenone, calcium antagonists, etc., all of which can cause second-degree atrioventricular block. 3. Organic heart disease: coronary heart disease, myocarditis, cardiomyopathy, etc. 4. Infection: Such as Coxsackie B virus infection, measles, mumps, viral upper respiratory tract infection, infectious mononucleosis, viral hepatitis, typhoid fever, etc. can cause extensive or local damage to the conduction system, so atrioventricular block occurs. 5. Other reasons: such as electrolyte disorder, drug poisoning, heart surgery, etc.