Drug treatment of coronary heart disease-2020 medical health pharmacy knowledge

Coronary atherosclerotic heart disease refers to heart disease caused by atherosclerosis of the coronary arteries so that the lumen of the narrowing, spasm or blockage leading to myocardial ischemia, hypoxia or necrosis, collectively referred to as coronary heart disease or coronary artery disease, coronary heart disease, categorized as ischemic heart disease, is atherosclerosis leading to the most common type of organ lesions. Drugs commonly used in the treatment of coronary heart disease are as follows:

I. Drugs that reduce symptoms and improve ischemia

Drugs that reduce symptoms and improve ischemia should be used in conjunction with drugs that prevent myocardial infarction and death, and some of these drugs, such as ? receptor blockers, do both. Current medications to reduce symptoms and improve ischemia include? receptor blockers, nitrates, and calcium antagonists (CCBs).

1.? Receptor blockers

? Receptor blockers can inhibit cardiac?1 adrenergic receptors, thereby slowing the heart rate, weakening myocardial contractility, lowering blood pressure, reducing myocardial oxygen consumption, reducing angina attacks in patients, and increasing exercise tolerance. The medication requires the resting heart rate to be reduced to 55-60 beats/min, and in patients with severe angina if there are no symptoms of bradycardia, the heart rate can be reduced to 50 beats/min. If there are no contraindications, ? receptor blockers should be used as the initial therapeutic agent for stable angina. According to the ? receptor blockers are divided into three categories:

① selective ?1 receptor blockers, mainly at the ?1 receptor, commonly used drugs for metoprolol (Betalucil), bisoprolol (Xinxin), atenolol (Aminoacetic acid), etc.;

② non-selective ?1 receptor blockers, the role of the ?1 and ?2 receptor, commonly used drugs for propranolol (Cardiovasc), which has been less used;

② non-selective ?1 receptor blockers, the role of ?1 and ?2 receptor, commonly used drugs for the ?2 receptor, which has been less used;

③ non-selective ?1 receptor blockers, the role of ?1 and ?2 receptors, commonly used drugs for propranolol (Cardiac glycosides).

③ Non-selective ? receptor blockers, can act on both ? and ?1 receptors, with the role of peripheral vasodilatation, commonly used drugs for Aroclor and Labetalol.

? receptor blockers reduce the risk of death and reinfarction in patients with stable angina after myocardial infarction. Currently available for the treatment of angina? There are several types of receptor blockers, all of which are effective in preventing angina attacks when given in adequate doses. Selective ?1 receptor blockers (e.g., metoprolol, bisoprolol, and atenolol) are preferred in order to minimize the adverse effects triggered by ?2 receptor blockade. Non-selective agents with both ?1 and ? receptor blocking non-selective ? receptor blocker medications, are also effective in the treatment of CSA (e.g., Arolol and Labetalol). They are contraindicated in patients with severe bradycardia and high degree of atrioventricular block, sinus node dysfunction, significant bronchospasm, or bronchial asthma? Receptor blockers.

2, nitrates

Nitrates are endothelium-dependent vasodilators that reduce myocardial oxygen consumption, improve myocardial perfusion, and relieve angina symptoms. Nitrates reflexively increase sympathetic tone, making the heart rate faster, so often combined with negative heart rate drugs such as ? receptor blockers or non-dihydropyridine CCBs for the treatment of CSA.The antianginal effect of the combination is superior to that of the drugs alone.

Sublingual or aerosolized nitroglycerin is used only for symptomatic relief of angina attacks, and may also be used a few minutes before exercise to minimize or avoid angina attacks. Long-acting nitrates are used to reduce the frequency and extent of angina attacks and may increase exercise tolerance. Long-acting nitrates are not suitable for the treatment of acute episodes of angina, but for the chronic long-term treatment of angina. Care should be taken to give adequate drug-free intervals (usually there should be a daily interval of 6 to 8 hours) to minimize the development of drug resistance. Such as labor type angina patients daytime medication, nighttime should stop; skin patch daytime patch, night removal.

Adverse effects of nitrate drugs include headache, facial flushing, heart rate reflex acceleration and hypotension, the above adverse reactions to short-acting nitroglycerin more obvious. The possibility of postural hypotension should be noted with the first dose of nitroglycerin containing nitroglycerin. Those who use sildenafil for erectile dysfunction should not apply nitrate drugs such as nitroglycerin within 24 hours in order to avoid hypotension, even life-threatening.

Severe aortic stenosis or hypertrophic obstructive cardiomyopathy caused by angina pectoris, should not use nitrates, because nitrates can reduce cardiac preload, reduce the left ventricular volume, further increase the degree of obstruction of the left ventricular outflow tract, and the use of nitrates in patients with severe aortic stenosis is also due to a reduction in preload and further reduce the volume of cardiac outflow, there is a risk of syncope.

3, CCB

Calcium channel blockers (CCB) are categorized into dihydropyridines and non-dihydropyridines.

① dihydropyridines: nifedipine, amlodipine;

② non-dihydropyridines: diltiazem, verapamil;

Dihydropyridine CCBs and nondihydropyridine CCBs are equally effective, the negative inotropic effect of nondihydropyridine CCBs is stronger. CCBs play a role in relieving angina pectoris through the improvement of coronary arterial blood flow and the reduction of myocardial oxygen consumption. CCBs are the first line of therapy for variant angina or for angina that is predominantly CAS. Diltiazem and verapamil slow atrioventricular conduction and are commonly used in patients with angina pectoris associated with atrial fibrillation or atrial flutter. They should not be used in patients with preexisting severe bradycardia, high degree of atrioventricular block, and morbid sinus node syndrome. Long-acting CCBs reduce angina attacks.

Common adverse effects of CCB include peripheral edema, constipation, palpitations, and facial flushing, and hypotension occurs from time to time; other adverse effects include headache, dizziness, and weakness. When a long-acting CCB must be applied for stable angina combined with heart failure, amlodipine or felodipine may be chosen.? The combination of a receptor blocker and a long-acting CCB is more effective than a single agent. In addition, when the two drugs are used in combination,? blockers also attenuate the reflex tachycardia caused by dihydropyridine CCBs.

Non-dihydropyridine CCBs diltiazem or verapamil can be used as a contraindication to ? receptor blockers as an alternative therapy in patients with contraindications to them. However, the combination of non-dihydropyridine CCBs and ? The combination of non-dihydropyridine CCBs and beta-blockers can make conduction block and the weakening of myocardial contractility more pronounced, and special vigilance is needed to avoid the combination of the two drugs in the elderly, patients with existing bradycardia or left ventricular dysfunction.

4, other therapeutic drugs

① Improve metabolic drugs: trimetazidine through the regulation of myocardial energy substrate, inhibit fatty acid oxidation, optimize myocardial energy metabolism, to improve myocardial ischemia and left heart function, to relieve angina. It can be combined with ? receptor blockers and other antimyocardial ischemic drugs in combination. The common dose is 60mg/d, divided into 3 oral doses.

② Nicorandil: Nicorandil has a unique dual pharmacological mechanism, can specifically open the coronary vascular smooth muscle potassium channels, improve microvascular function, but also has a nitrate-like effect, dilation of coronary arteries, stable angina pectoris and other types of angina pectoris have significant efficacy.

Multiple Choice Questions

1. The following are the adverse effects of nitroglycerin vasodilatation

A. accelerated heart rate B. throbbing headache

C. postural hypotension D. elevation of intraocular pressure

E. methemoglobinemia

Answer ABCD.This question is about the adverse effects of nitrate analogs. Mainly secondary to their vasodilatory effects: throbbing headache; flushing or burning sensation in the face; increased heart rate; decreased blood pressure and increased reflex heart rate.