A high blood-cholesterol level – that is, one over 6 mmol per litre or 238 mg per 100 ml – is undesirable as there appears to be a correlation between a high blood cholesterol and ATHEROMA, the form of arterial degenerative disease associated with coronary thrombosis and high blood pressure. This is well exempli?ed in DIABETES MELLITUS and HYPOTHYROIDISM, two diseases in which there is a high blood cholesterol, sometimes going as high as 20 mmol per litre; patients with these diseases are known to be particularly prone to arterial disease. There is also a familial disease known as hypercholesterolaemia, in which members of affected families have a blood cholesterol of around 18 mmol per litre or more, and are particularly liable to premature degenerative disease of the arteries. Many experts believe that there is no ‘safe level’ and that everybody should attempt to keep their cholesterol level as low as possible.
Cholesterol exists in three forms in the blood: high-density lipoproteins (HDLs) which are believed to protect against arterial disease, and a low-density version (LDLs) and very low-density type (VLDLs), these latter two being risk factors.
The rising incidence of arterial disease in western countries in recent years has drawn attention to this relationship between high levels of cholesterol in the blood and arterial disease. The available evidence indicates that there is a relationship between blood-cholesterol levels and the amount of fat consumed; however, the blood-cholesterol level bears little relationship to the amount of cholesterol consumed, most of the cholesterol in the body being produced by the body itself.
On the other hand, diets high in saturated fatty acids – chie?y animal fats such as red meat, butter and dripping – tend to raise the blood-cholesterol level; while foods high in unsaturated fatty acids – chie?y vegetable products such as olive and sun?ower oils, and oily ?sh such as mackerel and herring – tend to lower it. There is a tendency in western society to eat too much animal fat, and current health recommendations are for everyone to decrease saturated-fat intake, increase unsaturated-fat intake, increase daily exercise, and avoid obesity. This advice is particulary important for people with high blood-cholesterol levels, with diabetes mellitus, or with a history of coronary thrombosis (see HEART, DISEASES OF). As well as a low-cholesterol diet, people with high cholesterol values or arterial disease may be given cholesterol-reducing drugs such as STATINS, but this treatment requires full clinical assessment and ongoing medical monitoring. Recent research involving the world’s largest trial into the effects of treatment to lower concentrations of cholesterol in the blood showed that routine use of drugs such as statins reduced the incidence of heart attacks and strokes by one-third, even in people with normal levels of cholesterol. The research also showed that statins bene?ted women and the over-70s.... cholesterol
Arrhythmias An abnormal rate or rhythm of the heartbeat. The reason is a disturbance in the electrical impulses within the heart. Sometimes a person may have an occasional irregular heartbeat: this is called an ECTOPIC beat (or an extrasystole) and does not necessarily mean that an abnormality exists. There are two main types of arrhythmia: bradycardias, where the rate is slow – fewer than 60 beats a minute and sometimes so slow and unpredictable (heartblock) as to cause blackouts or heart failure; and tachycardia, where the rate is fast – more than 100 beats a minute. A common cause of arrhythmia is coronary artery disease, when vessels carrying blood to the heart are narrowed by fatty deposits (ATHEROMA), thus reducing the blood supply and damaging the heart tissue. This condition often causes myocardial infarction after which arrhythmias are quite common and may need correcting by DEFIBRILLATION (application of a short electric shock to the heart). Some tachycardias result from a defect in the electrical conduction system of the heart that is commonly congenital. Various drugs can be used to treat arrhythmias (see ANTIARRHYTHMIC DRUGS). If attacks constantly recur, the arrhythmia may be corrected by electrical removal of dead or diseased tissue that is the cause of the disorder. Heartblock is most e?ectively treated with an arti?cial CARDIAC PACEMAKER, a battery-activated control unit implanted in the chest.
Cardiomyopathy Any disease of the heart muscle that results in weakening of its contractions. The consequence is a fall in the e?ciency of the circulation of blood through the lungs and remainder of the body structures. The myopathy may be due to infection, disordered metabolism, nutritional excess or de?ciency, toxic agents, autoimmune processes, degeneration, or inheritance. Often, however, the cause is not identi?ed. Cardiomyopathies are less common than other types of heart diseases, and the incidence of di?erent types of myopathy (see below) is not known because patients or doctors are sometimes unaware of the presence of the condition.
The three recognised groups of cardiomyopathies are hypertrophic, dilated and restrictive.
•Hypertrophic myopathy, a familial condition, is characterised by great enlargement of the muscle of the heart ventricles. This reduces the muscle’s e?ciency, the ventricles fail to relax properly and do not ?ll suf?ciently during DIASTOLE.
In the dilated type of cardiomyopathy, both ventricles overdilate, impairing the e?ciency of contraction and causing congestion of the lungs.
In the restrictive variety, proper ?lling of the ventricles does not occur because the muscle walls are less elastic than normal. The result is raised pressure in the two atria (upper cavities) of the heart: these dilate and develop FIBRILLATION. Diagnosis can be di?cult and treatment is symptomatic, with a poor prognosis. In suitable patients, heart TRANSPLANTATION may be considered. Disorders of the heart muscle may also be
caused by poisoning – for example, heavy consumption of alcohol. Symptoms include tiredness, palpitations (quicker and sometimes irregular heartbeat), chest pain, di?culty in breathing, and swelling of the legs and hands due to accumulation of ?uid (OEDEMA). The heart is enlarged (as shown on chest X-ray) and ECHOCARDIOGRAPHY shows thickening of the heart muscle. A BIOPSY of heart muscle will show abnormalities in the cells of the heart muscle.
Where the cause of cardiomyopathy is unknown, as is the case with most patients, treatment is symptomatic using DIURETICS to control heart failure and drugs such as DIGOXIN to return the heart rhythm to normal. Patients should stop drinking alcohol. If, as often happens, the patient’s condition slowly deteriorates, heart transplantation should be considered.
Congenital heart disease accounts for 1–2 per cent of all cases of organic heart disease. It may be genetically determined and so inherited; present at birth for no obvious reason; or, in rare cases, related to RUBELLA in the mother. The most common forms are holes in the heart (atrial septal defect, ventricular septal defect – see SEPTAL DEFECT), a patent DUCTUS ARTERIOSUS, and COARCTATION OF THE AORTA. Many complex forms also exist and can be diagnosed in the womb by fetal echocardiography which can lead to elective termination of pregnancy. Surgery to correct many of these abnormalities is feasible, even for the most severe abnormalities, but may only be palliative giving rise to major diffculties of management as the children become older. Heart transplantation is now increasingly employed for the uncorrectable lesions.
Coronary artery disease Also known as ischaemic heart disease, this is a common cause of symptoms and death in the adult population. It may present for the ?rst time as sudden death, but more usually causes ANGINA PECTORIS, myocardial infarction (heart attack) or heart failure. It can also lead to a disturbance of heart rhythm. Factors associated with an increased risk of developing coronary artery disease include diabetes, cigarette smoking, high blood pressure, obesity, and a raised concentration of cholesterol in the blood. Older males are most affected.
Coronary thrombosis or acute myocardial infarction is the acute, dramatic manifestation of coronary-artery ischaemic heart disease – one of the major killing diseases of western civilisation. In 1999, ischaemic heart disease was responsible for about 115,000 deaths in England and Wales, compared with 153,000 deaths in 1988. In 1999 more than 55,600 people died of coronary thrombosis. The underlying cause is disease of the coronary arteries which carry the blood supply to the heart muscle (or myocardium). This results in narrowing of the arteries until ?nally they are unable to transport su?cient blood for the myocardium to function e?ciently. One of three things may happen. If the narrowing of the coronary arteries occurs gradually, then the individual concerned will develop either angina pectoris or signs of a failing heart: irregular rhythm, breathlessness, CYANOSIS and oedema.
If the narrowing occurs suddenly or leads to complete blockage (occlusion) of a major branch of one of the coronary arteries, then the victim collapses with acute pain and distress. This is the condition commonly referred to as a coronary thrombosis because it is usually due to the affected artery suddenly becoming completely blocked by THROMBOSIS. More correctly, it should be described as coronary occlusion, because the ?nal occluding factor need not necessarily be thrombosis.
Causes The precise cause is not known, but a wide range of factors play a part in inducing coronary artery disease. Heredity is an important factor. The condition is more common in men than in women; it is also more common in those in sedentary occupations than in those who lead a more physically active life, and more likely to occur in those with high blood pressure than in those with normal blood pressure (see HYPERTENSION). Obesity is a contributory factor. The disease is more common among smokers than non-smokers; it is also often associated with a high level of CHOLESTEROL in the blood, which in turn has been linked with an excessive consumption of animal, as opposed to vegetable, fats. In this connection the important factors seem to be the saturated fatty acids (low-density and very low-density lipoproteins [LDLs and VLDLs] – see CHOLESTEROL) of animal fats which would appear to be more likely to lead to a high level of cholesterol in the blood than the unsaturated fatty acids of vegetable fats. As more research on the subject is carried out, the arguments continue about the relative in?uence of the di?erent factors. (For advice on prevention of the disease, see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELFHELP.)
Symptoms The presenting symptom is the sudden onset, often at rest, of acute, agonising pain in the front of the chest. This rapidly radiates all over the front of the chest and often down over the abdomen. The pain is frequently accompanied by nausea and vomiting, so that suspicion may be aroused of some acute abdominal condition such as biliary colic (see GALLBLADDER, DISEASES OF) or a perforated PEPTIC ULCER. The victim soon goes into SHOCK, with a pale, cold, sweating skin, rapid pulse and dif?culty in breathing. There is usually some rise in temperature.
Treatment is immediate relief of the pain by injections of diamorphine. Thrombolytic drugs should be given as soon as possible (‘rapid door to needle time’) and ARRHYTHMIA corrected. OXYGEN is essential and oral ASPIRIN is valuable. Treatment within the ?rst hour makes a great di?erence to recovery. Subsequent treatment includes the continued administration of drugs to relieve the pain; the administration of ANTIARRHYTHMIC DRUGS that may be necessary to deal with the heart failure that commonly develops, and the irregular action of the heart that quite often develops; and the continued administration of oxygen. Patients are usually admitted to coronary care units, where they receive constant supervision. Such units maintain an emergency, skilled, round-the-clock sta? of doctors and nurses, as well as all the necessary resuscitation facilities that may be required.
The outcome varies considerably. The ?rst (golden) hour is when the patient is at greatest risk of death: if he or she is treated, then there is a 50 per cent reduction in mortality compared with waiting until hospital admission. As each day passes the prognosis improves with a ?rst coronary thrombosis, provided that the patient does not have a high blood pressure and is not overweight. Following recovery, there should be a gradual return to work, care being taken to avoid any increase in weight, unnecessary stress and strain, and to observe moderation in all things. Smoking must stop. In uncomplicated cases patients get up and about as soon as possible, most being in hospital for a week to ten days and back at work in three months or sooner.
Valvular heart disease primarily affects the mitral and aortic valves which can become narrowed (stenosis) or leaking (incompetence). Pulmonary valve problems are usually congenital (stenosis) and the tricuspid valve is sometimes involved when rheumatic heart disease primarily affects the mitral or aortic valves. RHEUMATIC FEVER, usually in childhood, remains a common cause of chronic valvular heart disease causing stenosis, incompetence or both of the aortic and mitral valves, but each valve has other separate causes for malfunction.
Aortic valve disease is more common with increasing age. When the valve is narrowed, the heart hypertrophies and may later fail. Symptoms of angina or breathlessness are common and dizziness or blackouts (syncope) also occur. Replacing the valve is a very e?ective treatment, even with advancing age. Aortic stenosis may be caused by degeneration (senile calci?c), by the inheritance of two valvular leaflets instead of the usual three (bicuspid valve), or by rheumatic fever. Aortic incompetence again leads to hypertrophy, but dilatation is more common as blood leaks back into the ventricle. Breathlessness is the more common complaint. The causes are the same as stenosis but also include in?ammatory conditions such as SYPHILIS or ANKYLOSING SPONDYLITIS and other disorders of connective tissue. The valve may also leak if the aorta dilates, stretching the valve ring as with HYPERTENSION, aortic ANEURYSM and MARFAN’S SYNDROME – an inherited disorder of connective tissue that causes heart defects. Infection (endocarditis) can worsen acutely or chronically destroy the valve and sometimes lead to abnormal outgrowths on the valve (vegetations) which may break free and cause devastating damage such as a stroke or blocked circulation to the bowel or leg.
Mitral valve disease leading to stenosis is rheumatic in origin. Mitral incompetence may be rheumatic but in the absence of stenosis can be due to ISCHAEMIA, INFARCTION, in?ammation, infection and a congenital weakness (prolapse). The valve may also leak if stretched by a dilating ventricle (functional incompetence). Infection (endocarditis) may affect the valve in a similar way to aortic disease. Mitral symptoms are predominantly breathlessness which may lead to wheezing or waking at night breathless and needing to sit up or stand for relief. They are made worse when the heart rhythm changes (atrial ?brillation) which is frequent as the disease becomes more severe. This leads to a loss of e?ciency of up to 25 per cent and a predisposition to clot formation as blood stagnates rather than leaves the heart e?ciently. Mitral incompetence may remain mild and be of no trouble for many years, but infection must be guarded against (endocarditis prophylaxis).
Endocarditis is an infection of the heart which may acutely destroy a valve or may lead to chronic destruction. Bacteria settle usually on a mild lesion. Antibiotics taken at vulnerable times can prevent this (antibiotic prophylaxis) – for example, before tooth extraction. If established, lengthy intravenous antibiotic therapy is needed and surgery is often necessary. The mortality is 30 per cent but may be higher if the infection settles on a replaced valve (prosthetic endocarditis). Complications include heart failure, shock, embolisation (generation of small clots in the blood), and cerebral (mental) confusion.
PERICARDITIS is an in?ammation of the sac covering the outside of the heart. The sac becomes roughened and pain occurs as the heart and sac rub together. This is heard by stethoscope as a scratching noise (pericardial rub). Fever is often present and a virus the main cause. It may also occur with rheumatic fever, kidney failure, TUBERCULOSIS or from an adjacent lung problem such as PNEUMONIA or cancer. The in?ammation may cause ?uid to accumulate between the sac and the heart (e?usion) which may compress the heart causing a fall in blood pressure, a weak pulse and circulatory failure (tamponade). This can be relieved by aspirating the ?uid. The treatment is then directed at the underlying cause.... heart, diseases of
Habitat: Throughout the tropical zones of India in the hilly regions.
English: Indian Kino tree, Malabar Kino tree.Ayurvedic: Asana, Bijaka, Priyaka, Pitashaala.Unani: Bijaysaar.Siddha/Tamil: Vengai.Action: Bark-kino—astringent, antihaemorrhagic, antidiarrhoeal. Flowers—febrifuge. Leaves—used externally for skin diseases.
Key application: Heartwood— in anaemia, worm infestation, skin diseases, urinary disorders, lipid disorders and obesity. Stem bark—in diabetes. (The Ayurvedic Pharmacopoeia of India.)The heartwood and roots contain isoflavonoids, terpenoids and tannins. Tannins include the hypoglycaemic principle (-)-epicatechin. Stilbenes, such as pterostilbene; flavonoids, including liquiritigenin, isoliquiritige- nin, 7-hydroxyflavanone, 7,4-dihy- droxyflavanone, 5-deoxykaempferol and pterosupin; a benzofuranone mar- supsin and propterol, p-hydroxy-ben- zaldehyde are active principles of therapeutic importance.The gum-kino from the bark provides a non-glucosidal tannin, Kino tannic acid (25-80%).The (-)-epi-catechin increases the cAMP content of the islets which is associated with the increased insulin release, conversion of proinsulin to insulin and cathepsin B activity.Oral administration of ethylacetate extract of the heartwood and its fla- vonoid constituents, marsupin, ptero- supin and liquiritigenin, for 14 consecutive days to rats exhibited a significant reduction of serum triglycerides, total cholesterol and LDL- and VLDL-cholesterol levels, but it did not exert any significant effect on HDL- cholesterol.The ethanolic and methanolic extracts of the heartwood exhibited significant in vitro antimicrobial activity against Gram-positive and Gramnegative bacteria and some strains of fungi.Kino is powerfully astringent. The therapeutic value of kino is due to Kino tannic acid.Dosage: Heartwood—50-100 g for decoction. (API, Vol. I); stem bark—32-50 g for decoction (API, Vol. III).... pterocarpus marsupiumHabitat: Cold temperate regions extending from Himalayas to northern Asia and Europe.
English: European Black Currant.Folk: Nabar.Action: Dried leaves and twigs— a home remedy for coughs. Leaves—diuretic, hypotensive, refrigerant. An infusion is used for inflammatory conditions, sore throat, hoarseness. Fruits— refrigerant, mildly spasmolytic, vasoprotective, anti-inflammatory.
Black currents are very rich in vitamin C (average 150 mg/100g) and contain 0.9-1.7% pectin as calcium pec- tate, also minerals, potassium (372 mg/ 100 g). The acidity of the fruit is mainly due to citric acid; malic acid is present in small amounts. Glucose and fructose are principal sugars; sucrose is a minor component.The flavonoids in the fruits include kaempferol, quercetin and myricetin. About 0.3% anthocyanosides, concentrated mainly in the skin, consist of glycosides of cyanidol and delphinidol.The anthocyanosides are reportedly bacteriostatic and exhibit vasopro- tective and anti-inflammatory activity. They are antisecretory against cholera toxin-induced intestinal fluid secretion in vitro.The leaves contain an anti-inflammatory principle, pycnometol and minute quantities of an essential oil composed mostly of terpenes.Polyphenolic extract of buds inhibited lipid peroxidation by rat liver mi- crosomes.Polyphenols present in R. nigrum and R. rubrum (Red Current, Western Himalayas from Kumaon to Kashmir) exhibit free radical scavenging activity. The seed oil lowers VLDL and total cholesterol.Contraindicated in bleeding disorders. (Sharon M. Herr.)... ribes nigrumHabitat: Cultivated as a food crop mainly in Punjab, Haryana, Uttar Pradesh., Madhya Pradesh, Maharashtra, Bihar and Rajasthan.
English: Wheat.Ayurvedic: Godhuuma.Folk: Gehun.Action: Wheat germ oil is rich in tocopherol (vitamin E) content, total tocopherols 1897 mcg/g, alpha tocopherol 67%. The presence of ergosterol (provitamin D) has also been reported.
Wheat germ is also used for its minerals, proteins and lipid contents. Germ proteins are rich in lysine (5.285.55 g/100 g protein) and possess high biological value (94%) and protein efficiency ratio (2.9).Wheat germ contains haemaggluti- nating and antipyretic factors, but these are destroyed by toasting. It also contains haemoproteins, possessing per- oxidase activity.In adult rats, addition of wheat germ (7%) to a high fat (cholesterol) diet significantly decreased VLDL-cholesterol and VLDL-triglycerides and increased the HDL-cholesterol after-7 weeks of feeding.Bran oil contains tocopherols, but major part of them (68%) is in epsilon form; alpha-tocopherol forms only 11% of the total.Gluten lipids, associated with gluten, contain a high percentage of linoleic acid; lowering of serum cholesterol level has been observed in experiments (lipid-free gluten is devoid of cholesterol-lowering effect).Sensitivity to gluten has also been reported (even when whole wheat flour was used).... triticum aestivumFats are usually solid at room temperature; oils are liquid. The amount and types of fat in the diet have important implications for health. A diet containing a large amount of fat, particularly saturated fat, is linked to an increased risk of atherosclerosis and subsequent heart disease and stroke.
Some dietary fats, mainly triglycerides (combinations of glycerol and 3 fatty acids), are sources of the fat-soluble vitamins A, D, E, and K and of essential fatty acids. Triglycerides are the main form of fat stored in the body. These stores act as an energy reserve and also provide insulation and a protective layer for delicate organs. Phospholipids are structural fats found in cell membranes. Sterols, such as cholesterol, are found in animal and plant tissues; they have a variety of functions, often being converted into hormones or vitamins.
Dietary fats are first emulsified by bile salts before being broken down by lipase, a pancreatic enzyme. They are absorbed via the lymphatic system before entering the bloodstream.Lipids are carried in the blood bound to protein; in this state they are known as lipoproteins. There are 4 classes of lipoprotein: very low-density lipoproteins (VLDLs), low-density lipoproteins (LDLs), high-density lipoproteins (HDLs), and chylomicrons. LDLs and VLDLs contain large amounts of cholesterol, which they carry through the bloodstream and deposit in tissues. HDLs pick up cholesterol and carry it back to the liver for processing and excretion. High levels of LDLs are associated with atherosclerosis, whereas HDLs have a protective effect. (See also nutrition.)... fats and oils
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