Digitalis drugs, which are very common in cardiovascular medicine, mainly include digoxin, sildenafil, and toxic trichothecene K. They are very commonly used in clinical practice, especially digoxin and sildenafil are more common. The pharmacological effects of digitalis drugs, mainly positive inotropic and negative frequency effects, are commonly used in the treatment of heart failure and atrial fibrillation. In acute heart failure, cediran can be used intravenously; in chronic heart failure, digoxin can be used in oral maintenance doses; in rapid atrial fibrillation, cediran can be injected intravenously to restore the rhythm. Its contraindications are: i. No digitalis drugs within the first 24 hours of acute myocardial infarction; ii. No digitalis drugs for digitalis poisoning; iii. No digitalis drugs for hypertrophic obstructive cardiomyopathy; iv. No digitalis drugs for simple mitral stenosis with sinus rhythm; v. Use with caution for hepatic and renal insufficiency.