Routine treatment: NYHA cardiac function classification: ① Grade Ⅰ: controlling risk factors; ACE inhibitor. ② Grade Ⅱ: ACE inhibitor; Diuretics; Beta blockers; With or without digoxin. ③ Grade Ⅲ: ACE inhibitor; Diuretics; Beta blockers; Digoxin. ④ ⅳ: ACE inhibitor; Diuretics; Digoxin; Aldosterone receptor antagonist; After the condition is stable, β -blockers should be used cautiously. Drug therapy: (1) diuretic mechanism: reducing cardiac preload. Classification: potassium excretion and potassium preservation ① furosemide: potassium excretion, fast and powerful; Intravenous injection and oral administration are used for acute and severe cardiac insufficiency; Pay attention to hypokalemia and hypotension; (2) ②DHCT: Potassium excretion, oral, mild; Pay attention to hypokalemia, hyperglycemia, elevated uric acid and dyslipidemia. Spironolactone: potassium-preserving, oral, slow; Pay attention to the combination of high potassium, potassium excretion and potassium preservation, and use it intermittently in small doses. Attention: Prevent electrolyte disorder (low potassium, low sodium, etc. ). Common preparations: ① Potassium-releasing diuretic: hydrochlorothiazide (hydrochlorothiazide), 25 ~ 50mg orally, 2 ~ 3 times a day; Furosemide is a powerful diuretic, which can be administered orally or intramuscularly, 20mg, 2 ~ 3 times a day, or intravenously. ② Potassium-preserving diuretics, such as spironolactone (spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone, spironolactone. Dilated arteries: nifedipine, phentolamine, ACEI, should be used with caution, or even prohibited for patients with valve stenosis and hypertrophic obstructive cardiomyopathy. Dilating arteries and veins: sodium nitroprusside and prazosin, valve stenosis and hypertrophic obstructive cardiomyopathy should be used with caution or even banned. Attention: Hypotension, especially postural hypotension. Indications: At present, the routine treatment of chronic heart failure does not include simple vasodilators. 1) moderate and severe chronic left heart failure, no contraindications can be applied. 2) Valve regurgitation heart disease and ventricular septal defect. Contraindications: hypovolemia, hypotension and renal failure. Commonly used drugs: ① sodium nitroprusside, the initial dose is 10μg/min, and then it is increased by 5 ~ 10μ g/min every 5 ~ 10 min until it produces curative effect or adverse reaction. (2) Nitroglycerin is the main vasodilator, but its dilating effect on peripheral arterioles is weak. It can be increased to 50 ~ 100μ g/min by taking 0.3mg/ time and intravenous drip. ③ Phentolamine mainly dilates arteries and veins, and started intravenous drip of 0. 1mg/min, and maintained at 0.3mg/min. ④ACEI: Enalapril, Benazepril, Perindopril, etc. (3) cardiotonic: ① digitalis mechanism: inhibiting Na+-K+-ATPase, increasing Na+-Ca2+ exchange and enhancing myocardial contractility; Stimulate vagus nerve to slow down heart rate; Negative conduction. Indications: cardiac insufficiency, supraventricular tachyarrhythmia. Heart enlargement, heart failure with atrial fibrillation is the best. Contraindications: preexcitation complicated with atrial fibrillation, bradyarrhythmia, hypertrophic obstructive cardiomyopathy, sinus rhythm of mitral stenosis and obvious hypokalemia. Digitalis has poor curative effect on cor pulmonale and dilated cardiomyopathy and is easy to be poisoned. Type: quick-acting: poison K, cedilanid, intravenous application. Medium effect: digoxin, oral. Administration method: maintenance dose method. Precautions should be applied: the principle of individualization can reduce the following situations. Such as renal insufficiency; Elderly patients; Hypothyroidism; Low potassium; Coronary heart disease, myocarditis, cardiomyopathy and cor pulmonale; Drug combination. Commonly used preparation: 1) Ceylon is a quick-acting preparation, which is given by slow intravenous injection at the rate of 0.2 ~ 0.4mg/ time, and the total amount can reach 1 ~ 1.6mg/ time within 24 hours, and is given by slow intravenous injection at the rate of 0.25 ~ 0.5mg/ time. 2) Digoxin, an intermediate preparation, is administered according to the routine maintenance method. Dobutamine: acts on b 1 receptor. Milrinone: phosphodiesterase inhibitor, short-term application for refractory cardiac insufficiency. (4) The mechanism of ACEI: dilate arterioles and veins, and reduce the preload and afterload of the heart; Prevent and reverse cardiovascular remodeling; Inhibit aldosterone secretion. Precautions for use: Chronic cardiac insufficiency is the first choice, and patients with chronic renal failure, hyperkalemia, pregnancy and bilateral renal artery stenosis should use it with caution. Generally, it is not used with potassium-preserving diuretics and potassium salts. Common side effects: cough, high potassium and urea nitrogen. Commonly used drugs: captopril, enalapril, benazepril, perindopril, etc. (5)ARB: Blocking angiotensin Ⅱ at1receptor, and its mechanism is similar to ACEI. Commonly used drugs: valsartan, irbesartan, etc. (6)b receptor blocker: Mechanism: inhibition of sympathetic nerve overexcitation. It should be noted that it is suitable for patients with chronic cardiac insufficiency and cardiac function grade II and III. Start with a small dose, gradually increase the amount and maintain it properly; Symptoms may be aggravated at the initial stage of use and take effect for a long time. Side effects: bradycardia, hypotension and deterioration of cardiac function. Commonly used drugs: metoprolol and bisoprolol; Carvedilol (β, α receptor blocker). (7) Aldosterone receptor antagonist mechanism: inhibiting cardiovascular remodeling and improving the long-term prognosis of chronic heart failure. Side effects: increased blood potassium, especially when combined with ACEI. Commonly used drugs: spironolactone 20mg 1 ~ 2 times a day.