Part 4
-Beta blockers
-Calcium channel blockers
-Antianginal drugs
-Antiasthmatic drugs
1)-Beta Blockers
*Beta blockers are a class of drugs that block beta-adrenergic substances such as adrenaline (epinephrine), a key agent in the "sympathetic" portion of the autonomic (involuntary) nervous system and activation of heart muscle.
-By blocking the action of the involuntary nervous system on the heart, beta blockers relieve stress on the heart. They slow the heart beat, lessen the force with which the heart muscle contracts and reduce blood vessel contraction in the heart, brain, and throughout the body.
*-Beta blockers can serve to treat abnormal heart rhythms (
cardiac arrhythmias). They are used specifically to prevent abnormally fast heart rates (tachycardias) or irregular heart rhythms such as premature ventricular beats.
1)-Since beta blockers reduce the demand of the heart muscle for oxygen and the chest pain of angina pectoris occurs when the oxygen demand of the heart exceeds the supply, beta blockers can be useful in treating angina. They have also become an important drug in improving survival after a person has had a heart attack.
2)-Thanks to their effect on blood vessels, beta blockers can lower the blood pressure and be of value in the treatment ofhypertension.
3)-Other uses for beta blockers include the prevention of migraine headaches and stage fright (social phobia),
4)- the treatment of certain types of tremors(familial or hereditary essential tremors).
-The beta blockers (with brand names) include acebutolol (Sectral), atenolol (Tenormin), bisoprolol (Zebeta), metoprolol (Lopressor, Lopressor LA, Toprol XL), nadolol (Corgard) and timolol (Blocadren). Beta blockers are also available in combination with a diuretic as, for example, with bisoprolol and hydrochlorothiazide (Ziac).
5)_Beta blockers reduce the pressure within the eye (the intraocular pressure), probably by reducing the production of the liquid (aqueous humor) within the eye, and so are used to lessen the risk of damage to the optic nerve and loss of vision in
glaucoma. Beta blocker preparations for this purpose include timolol ophthalmic solution (Timoptic) and betaxolol hydrochloride (Betoptic, Betoptic S).
from MedicineNet:
Beta blockers are a class of drugs that block beta-adrenergic substances such as adrenaline (epinephrine), a key agent in the "sympathetic" portion of the autonomic (involuntary) nervous system and activation of heart muscle. By blocking the action of the involuntary nervous system on the heart, beta blockers relieve stress on the heart. Beta blockers serve to treat abnormal and irregular heart rhythms, chest pain, heart attack, hypertension, migraines, social phobias, tremors, and glaucoma. The beta blockers (with brand names) include acebutolol (Sectral), atenolol (Tenormin), bisoprolol (Zebeta), metoprolol (Lopressor, Lopressor LA, Toprol XL), nadolol (Corgard), and timolol (Blocadren
*What is heart disease ?
Heart disease is any disorder that affects the heart. Sometimes the term "heart disease" is used narrowly and incorrectly as a synonym for coronary artery disease.
Heart disease is synonymous with cardiac disease but not with cardiovascular disease which is any disease of the heart or blood vessels.
*Heart disease – types of heart disease :
When you think of heart disease, usually people think of coronary artery disease (narrowing of the arteries leading to the heart), but coronary artery disease is just one type of heart disease.
Among the many types of heart disease, see, for example: Angina; Arrhythmia; Congenital heart disease; Coronary artery disease (CAD); Dilated cardiomyopathy; Heart attack (myocardial infarction); Heart failure; Hypertrophic cardiomyopathy; Mitral regurgitation; Mitral valve prolapse; and Pulmonary stenosis.
Heart disease is the leading cause of death for both men and women in the world.
Heart disease is important to learn about your to help prevent heart disease. And, if you have cardiovascular disease, you can live a healthier, more active life by learning about your heart disease and treatments and by becoming an active participant in your care.
*Most famous heart disease :
-Coronary Artery heart disease :
Coronary artery disease (CAD) is atherosclerosis, or hardening, of the arteries that provide vital oxygen and nutrients to the heart.
-Abnormal Heart Rhythms heart disease :
The heart is an amazing organ. It beats in a steady, even rhythm, about 60 to 100 times each minute (that's about 100,000 times each day!). But, sometimes your heart gets out of rhythm. An irregular or abnormal heartbeat is called an arrhythmia. An arrhythmia heart disease (also called a dysrhythmia) can involve a change in the rhythm, producing an uneven heartbeat, or a change in the rate, causing a very slow or very fast heartbeat.
-Heart disease - Heart Failure :
The term "heart failure" can be frightening. It does not mean the heart has "failed" or stopped working. It means the heart does not pump as well as it should.
Heart failure heart disease is a major health problem in the U.S., affecting nearly 5 million Americans. About 550,000 people are diagnosed with heart failure each year.
Heart disease failure is the leading cause of hospitalization in people older than 65.
-Congenital Heart Disease :
Congenital heart disease is a type of defect in one or more structures of the heart or blood vessels that occur before birth. It affects about 8 out of every 1,000 children.
In this heart disease - Congenital heart defects may produce symptoms at birth, during childhood and sometimes not until adulthood.
In most cases scientists don't know why they occur. Heredity may play a role as well as exposure to the fetus during pregnancy to certain viral infections, alcohol or drugs.
-Cardiomyopathies heart disease:
Cardiomyopathies heart disease are diseases of the heart muscle itself. People with cardiomyopathies heart disease have hearts that are abnormally enlarged, thickened and/or stiffened. As a result, the heart's ability to pump blood is weakened. Without treatment, cardiomyopathies worsen over time and often lead to heart failure and abnormal heart rhythms.
-Aorta heart Disease and Marfan syndrome heart disease:
The aorta is the large artery that leaves the heart and provides oxygen-rich blood throughout the body.
Some conditions can cause the aorta to dilate (widen) or dissect (tear), increasing the risk for future life-threatening events
People with aorta heart disease should be treated by an experienced team of cardiovascular specialists and surgeons.
*Heart disease – other important terms you should know :
Heart disease - Tachycardia is an abnormally rapid beating of the heart, defined as a resting heart rate of 100 or more beats per minute in an average adult.
-Heart disease - heart murmur is an extra or unusual sound heard during your heartbeat. Murmurs range from very faint to very loud and sometimes sound like a whooshing or swishing noise. Normal heartbeat sounds—"lub-DUPP" or "lub-DUB"—are the valves closing as blood moves through the heart. (Go to the How the Heart Works section for more information about how a normal heart works.)
-Heart disease - Beta blockers are a class of drugs used for various indications, but particularly for the management of cardiac arrhythmias and cardioprotection after myocardial infarction.
-Heart disease - Malignant hyperthermia (MH or MHS for "malignant hyperthermia syndrome", or "malignant hyperpyrexia due to anesthesia") is a life-threatening condition resulting from a genetic sensitivity of skeletal muscles to volatile anaesthetics and depolarizing neuromuscular blocking drugs that occurs during or after anaesthesia. It is related to, but distinct from, the neuroleptic malignant syndrome.
-Heart disease -stent is either an expandable wire form or perforated tube (conventionally perforated by means of laser cutting) that is inserted into a natural conduit of the body to prevent or counteract a disease-induced localized flow constriction.
-Heart disease - Mitral valve prolapse (MVP) is a disorder that affects one of your heart's valves — the mitral valve. It occurs when the valve doesn't close correctly, allowing backward leaking of blood in your heart.
*BETA-BLOCKERS - a patient's guide
Drug/Brand Name
Acebutolol: ACB, Sectral
Alprenolol: Aptin CR
Atenolol: Ansolol, Apo-Atenolol, Loten, Tenormin
Celiprolol: Selectol
Labetolol: Hybloc, Trandate
Metoprolol: Betaloc CR, Lopressor
Nadolol: Apo-Nadolol, Corgard
Oxprenolol: Captol, Trasicor
Pindolol: Apo-Pindolol, Pindol, Visken, Vypen
Propranolol: Angilol, Apo-Propranolol, Cardinol, Inderal
Sotalol: Pacific, Sotacor
Timolol: Apo-Timolol, Hypermol, Tilmat, Blocadre
*Use:
Beta-adrenoreceptor blocking agents
This group of medicines are used for
-Hypertension (high blood pressure),
-Angina (chest pain),
-After myocardial infarction (heart attack)
-Arrhythmias (heart irregularities). Other uses include
-Anxiety,
-Prevention of migraine,
-Glaucoma and
-Thyrotoxicosis (to control the symptoms).
They have been extensively studied and shown to decrease the risk of stroke other complications in patients with high blood pressure. They have been shown to reduce the risk of death and further problems after a heart attack.
Beta-blockers work by reducing the heart rate and dilate blood vessels through blocking adrenoreceptors. However, they also have unwanted problems including bronchospasm and for this reason should not be used in asthmatics. This is often taken into consideration before prescribing a beta-blocker to treat your condition by the doctor.
*Cautions
-Asthma (don't use) and lung problems
-Hypersensitivity conditions (worsen allergens)
-Heart failure, myasthenia gravis
-Diabetics (may affect glucose control)
-Pregnancy and breastfeeding
-Abrupt withdrawal in angina
-Metabolic acidosis, anaesthesia
-Liver and kidney impairment
*Side effects
-Occasional: cold extremities, fatigue, dizziness, dry mouth, bronchospasm.
-Rarely: skin rash, hair loss, stomach upset, dry eyes, heart problems
*Interactions
Enhanced effects seen with ACE inhibitors, alcohol, anaesthetics, anti-arrhythmics, antihistamines, antidepressants, calcium-channel blockers, diuretics, antihypertensives, antibacterials, anxiolytics, antipsychotics and some other medicines.
Oral contraceptives, HRT, corticosteroids, analgesics, adrenaline can antagonise effects.
*Patient information
Follow the instructions on the label of this medicine.
Do not stop taking this medicine except on your doctor's advice.
It can be dangerous to suddenly stop B-blockers, especially in the presence of heart problems.
Alcohol: restrict intake due to enhanced hypotensive effect (dizziness).
Avoid taking other medicines unless directed by your doctor/pharmacist.
Contact your doctor or seek medical attention if side effects are severe or ongoing.
2)-Calcium Channel Blockers
(CCBs)
What are CCBs and how do they work?
Calcium channel blockers are a class of drugs that block the entry of calcium into the muscle cells of the heart and the arteries. It is the entry of calcium into these cells that causes the heart to contract and arteries to narrow. By blocking the entry of calcium, CCBs decrease contraction of the heart and dilate (widen) the arteries.
In order to pump blood, the heart needs oxygen. The harder the heart works, the more oxygen it requires. Angina (heart pain) occurs when the supply of oxygen to the heart is inadequate for the amount of work the heart must do. By dilating the arteries, CCBs reduce the pressure in the arteries. This makes it easier for the heart to pump blood, and, as a result, the heart needs less oxygen. By reducing the heart's need for oxygen, CCBs relieve or prevent angina. CCBs also are used for treating high blood pressure because of their blood pressure-lowering effects. CCBs also slow the rate at which the heart beats and are therefore used for treating certain types of abnormally rapid heart rhythms.
For what conditions are CCBs used?
CCBs are used for treating high blood pressure, angina, and abnormal heart rhythms (e.g., atrial fibrillation). They also may be used after a heart attack, particularly among patients who cannot tolerate beta-blocking drugs, have atrial fibrillation, or require treatment for their angina. (Unlike beta blockers, CCBs have not been shown to reduce mortality or additional heart attacks after a heart attack.) CCBs are as effective as ACE inhibitors in reducing blood pressure, but they may not be as effective as ACE inhibitors in preventing the kidney failure of high blood pressure or diabetes.
Are there any differences among CCBs?
CCBs differ in their duration of action, the process by which they are eliminated from the body, and, most importantly, in their ability to affect heart rate and contraction. Some CCBs (e.g., amlodipine) have very little effect on heart rate and contraction so they are safer to use in individuals who have heart failure or bradycardia (a slow heart rate). Verapamil and diltiazem have the greatest effects on the heart and reduce the strength and rate of contraction. Therefore, they are used in reducing heart rate when the heart is beating too fast.
What are the side effects of CCBs?
The most common side effects of CCBs are constipation, nausea, headache, rash, edema (swelling of the legs with fluid), low blood pressure, drowsiness, and dizziness. When diltiazem or verapamil are given to individuals with heart failure, symptoms of heart failure may worsen because these drugs reduce the ability of the heart to pump blood.
With which drugs do CCBs interact?
Most of the interactions of CCBs occur with verapamil or diltiazem. The interaction occurs because verapamil and diltiazem decrease the elimination of a number of drugs by the liver. Through this mechanism, verapamil and diltiazem may reduce the elimination and increase the blood levels of carbamazepine (Tegretol), simvastatin (Zocor), atorvastatin (Lipitor), and lovastatin (Mevacor). This can lead to toxicity from these drugs.
What CCBs are available?
The CCBS that have been approved for use in the US include nisoldipine (Sular), nifedipine (Adalat, Procardia), nicardipine (Cardene), bepridil (Vascor), isradipine (Dynacirc), nimodipine (Nimotop), felodipine (Plendil), amlodipine (Norvasc), diltiazem (Cardizem), and verapamil (Calan, Isoptin).
Calcium channel blockers prevent calcium from entering cells of the heart and blood vessel walls.
This results in lower blood pressure. Calcium channel blockers, also called calcium antagonists, relax and widen blood vessels by affecting the muscle cells in the arterial walls.
Some of the medications in this class have the added benefit of slowing your heart rate, which can further lower blood pressure.
Examples of calcium channel blockers
There are two types of calcium channel blockers: short-acting and long-acting. Short-acting medications work quickly, but their effects last only a few hours. Long-acting medications take longer to start working, but their effects last longer.
Several calcium antagonists are available. Which one is best for you depends on your health and the condition being treated.
Examples of calcium antagonists include:
§ Amlodipine (Norvasc)
§ Diltiazem (Cardizem, Dilacor XR)
§ Nifedipine (Adalat, Procardia)
§ Verapamil (Calan, Isoptin, Verelan, Covera)
Under special circumstances, your doctor might prescribe a calcium channel blocker along with other high blood pressure drugs or with cholesterol-lowering drugs such as statins.
Uses for calcium channel blockers
Doctors prescribe calcium channel blockers to prevent, treat or improve symptoms in a variety of conditions, such as:
§ High blood pressure
§ Chest pain (angina)
§ Migraines
§ Brain aneurysm complications
§ Irregular heartbeats (arrhythmia)
§ Raynaud's disease
§ Pulmonary hypertension
Side effects and cautions
Side effects of calcium channel blockers include constipation, headache, rapid heartbeat, rash, drowsiness, flushing, nausea, and swelling in the feet and lower legs.
Certain calcium channel blockers interact with grapefruit products. Don't take these medications with grapefruit or grapefruit juice because they can reduce your liver's ability to eliminate calcium channel blockers from your body, allowing the medications to build up in your body.
Description
Amlodipine, bepridil, diltiazem, felodipine, flunarizine, isradipine, nicardipine, nifedipine, nimodipine, and verapamil belong to the group of medicines called calcium channel blocking agents.
Calcium channel blocking agents affect the movement of calcium into the cells of the heart and blood vessels. As a result, they relax blood vessels and increase the supply of blood and oxygen to the heart while reducing its workload.
Some of the calcium channel blocking agents are used to relieve and control angina pectoris (chest pain).
Some are also used to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled.
Flunarizine is used to prevent migraine headaches.
Nimodipine is used to prevent and treat problems caused by a burst blood vessel around the brain (also known as a ruptured aneurysm or subarachnoid hemorrhage).
Other calcium channel blocking agents may also be used for these and other conditions as determined by your doctor.
These medicines are available only with your doctor's prescription, in the following dosage forms:
Oral
- Amlodipine
- Tablets (U.S. and Canada)
- Bepridil
- Tablets (U.S.)
- Diltiazem
- Extended-release capsules (U.S. and Canada)
- Extended-release tablets (U.S.)
- Tablets (U.S. and <SPAN
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